Short interval overnight laser scanning suggest sub-circadian periodicity of tree turgor

DEFF Research Database (Denmark)

Zlinszky, Andras; Barfod, Anders

2018-01-01

in amplitude and 2-6hour periodicity. Sub-circadian process dynamics of plants were so far not in focus of research, but here we compare the findings with other published cases of short-term periodicity in leaf turgor, sap flow and especially trunk diameter. Several authors have noted overnight variations...

Short interval overnight laser scanning suggests sub-circadian periodicity of tree turgor

DEFF Research Database (Denmark)

Zlinszky, Andras; Barfod, Anders

2018-01-01

in amplitude and 2-6hour periodicity. Sub-circadian process dynamics of plants were so far not in focus of research, but here we compare the findings with other published cases of short-term periodicity in leaf turgor, sap flow and especially trunk diameter. Several authors have noted overnight variations...

Selecting Full-Text Undergraduate Periodicals Databases.

Science.gov (United States)

Still, Julie M.; Kassabian, Vibiana

1999-01-01

Examines how libraries and librarians can compare full-text general periodical indices, using ProQuest Direct, Periodical Abstracts (via Ovid), and EBSCOhost as examples. Explores breadth and depth of coverage; manipulation of results (email/download/print); ease of use (searching); and indexing quirks. (AEF)

CT findings suggesting anastomotic leak and predicting the recovery period following gastric surgery

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Ho; Kim, Jung Hoon; Shin, Cheong-Il; Kim, Se Hyung; Han, Joon Koo; Choi, Byung Ihn [Seoul National University College of Medicine, Department of Radiology, Institute of Radiation Medicine, Jongno-gu, Seoul (Korea, Republic of)

2015-07-15

To assess diagnostic performance of routine CT for detecting anastomotic leak after gastric surgery, and analyse the relationship between recovery period and CT findings. We included 179 patients who underwent immediate CT and fluoroscopy after gastric surgery. Two reviewers retrospectively rated the possibility of leak on CT using a five-point scale focused on predefined CT findings. They also evaluated CT findings. Patients were categorised as: Group I, leak on fluoroscopy; Group II, possible leak on CT but negative on fluoroscopy; Group III, no leak. We analysed the relationship between recovery period and group. Area under the curve for detecting leak on CT was 0.886 in R1 and 0.668 in R2 with moderate agreement (k = 0.482). Statistically common CT findings for leak included discontinuity, large amount of air-fluid and wall thickening at anastomosis site (p < 0.05). Discontinuity at anastomosis site and a large air-fluid collection were independently associated with leak (p < 0.05). The recovery period including hospitalisation and postoperative fasting period was longer in Group I than Group II or III (p < 0.05). Group II showed a longer recovery period than Group III (p < 0.05). Postoperative routine CT was useful for predicting anastomotic leak using specific findings, and for predicting length of recovery period. (orig.)

Evaluation and selection of NPPs for medium term period around 2020

International Nuclear Information System (INIS)

Zezula, L.

2004-01-01

The Czech Republic is one of the European countries where a nuclear option remains open as a part of an energy mix. This will help the country to meet its international commitments under the Kyoto Protocol. Moreover the country has also its own industrial potential which can significantly contribute to possible construction of a new nuclear source both in the Czech Republic and abroad. Therefore, the selection of a new nuclear source which could be connected to the national grid after 2020 is actually a pressing issue. General features of economics assessment philosophy as to electricity generation costs are briefly discussed, and an overview of basic economic assessment methods is presented. An example of the economic calculations for a small grid is also given. General approach to the evaluation of advanced nuclear power plants projects (feasible for the period around 2020) are discussed. A simple method of the preliminary evaluation and selection of a suitable type of the plant is presented and general targets which are prerequisite and follow also from important international activities (GIF project and INPRO project) are elucidated. (author)

Suggestions on selection of clay site as a key alternative of underground repository for HLW geological disposal in China

International Nuclear Information System (INIS)

Zheng Hualing; Fu Bingjun; Fan Xianhua; Chen Shi; Sun Donghui

2006-01-01

Site selection for the underground repository is a vital problem with respect to the HLW geological disposal. Over the past decades, we have been focusing our attention on granite as a priority in China. However, there are some problems have to be discussed on this matter. In this paper, both experiences gained and lessons learned in the international community regarding the site selection are described. And then, after analyzing a lot of some key factors affecting the site selection, some comments and suggestions on selection of clay site as a key alternative before final decision making in China are presented. (authors)

Backward Response-Level Crosstalk in the Psychological Refractory Period Paradigm

Science.gov (United States)

Miller, Jeff; Alderton, Mark

2006-01-01

Bottleneck models of psychological refractory period (PRP) tasks suggest that a Task 1 response should be unaffected by the Task 2 response in the same trial, because selection of the former finishes before selection of the latter begins. Contrary to this conception, the authors found backward response-level crosstalk effects in which Task 2…

Lengthened Cutaneous Silent Period in Fibromyalgia Suggesting Central Sensitization as a Pathogenesis.

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Seol-Hee Baek

Full Text Available The pathogenesis of fibromyalgia (FM has not been clearly elucidated, but central sensitization, which plays an important role in the development of neuropathic pain, is considered to be the main mechanism. The cutaneous silent period (CSP, which is a spinal reflex mediated by A-delta cutaneous afferents, is useful for the evaluation of sensorimotor integration at the spinal and supraspinal levels. To understand the pathophysiology of FM, we compared CSP patterns between patients with FM and normal healthy subjects. Twenty-four patients with FM diagnosed in accordance with the 1990 American College of Rheumatology classification system and 24 age- and sex-matched healthy volunteers were recruited. The CSP was measured from the abductor pollicis brevis muscle. Demographic data, number of tender points, and visual analog scale and FM impact questionnaire scores were collected. The measured CSP and clinical parameters of the patient and control groups were compared. In addition, possible correlations between the CSP parameters and the other clinical characteristics were analyzed. Mean CSP latencies did not differ between patients (55.50 ± 10.97 ms and healthy controls (60.23 ± 11.87 ms; p = 0.158, although the mean CSP duration was significantly longer in patients (73.75 ± 15.67 ms than in controls (63.50 ± 14.05 ms; p = 0.021. CSP variables did not correlate with any clinical variables. The significantly longer CSP duration in FM patients suggests central dysregulation at the spinal and supraspinal levels, rather than peripheral small fiber dysfunction.

Sensory trait variation in an echolocating bat suggests roles for both selection and plasticity

Science.gov (United States)

2014-01-01

significant sensory trait differentiation in the presence of historical gene flow and suggests roles for both selection and plasticity in the evolution of echolocation variation in R. capensis. These results highlight the importance of population level analyses to i) illuminate the subtle interplay between selection, plasticity and gene flow in the evolution of adaptive traits and ii) demonstrate that evolutionary processes may act simultaneously and that their relative influence may vary across different environments. PMID:24674227

Activity and selectivity control through periodic composition forcing over Fischer-Tropsch catalysts

Energy Technology Data Exchange (ETDEWEB)

Silveston, P L; Hudgins, R R; Adesina, A A; Ross, G S; Feimer, J L

1986-01-01

Data collected under steady-state and periodic composition forcing of the Fischer-Tropsch synthesis over three commonly used catalysts demonstrate that both activity and selectivity can be changed by the latter operating mode. Synthesis of hydrocarbons up to C/sub 7/are favored at the expense of the higher carbon numbers for the Co catalyst, while for the Ru catalyst, only the C/sub 3/ and lower species are favored. Only methane production is stimulated with the Fe catalyst. Fe and Ru catalysts shift production from alkenes to alkanes. Transient data is interpreted in the paper.

Influence of Selective Edge Removal and Refractory Period in a Self-Organized Critical Neuron Model

International Nuclear Information System (INIS)

Lin Min; Gang, Zhao; Chen Tianlun

2009-01-01

A simple model for a set of integrate-and-fire neurons based on the weighted network is introduced. By considering the neurobiological phenomenon in brain development and the difference of the synaptic strength, we construct weighted networks develop with link additions and followed by selective edge removal. The network exhibits the small-world and scale-free properties with high network efficiency. The model displays an avalanche activity on a power-law distribution. We investigate the effect of selective edge removal and the neuron refractory period on the self-organized criticality of the system. (condensed matter: structural, mechanical, and thermal properties)

An Expression of Periodic Phenomena of Fashion on Sexual Selection Model with Conformity Genes and Memes

Science.gov (United States)

Mutoh, Atsuko; Tokuhara, Shinya; Kanoh, Masayoshi; Oboshi, Tamon; Kato, Shohei; Itoh, Hidenori

It is generally thought that living things have trends in their preferences. The mechanism of occurrence of another trends in successive periods is concerned in their conformity. According to social impact theory, the minority is always exists in the group. There is a possibility that the minority make the transition to the majority by conforming agents. Because of agent's promotion of their conform actions, the majority can make the transition. We proposed an evolutionary model with both genes and memes, and elucidated the interaction between genes and memes on sexual selection. In this paper, we propose an agent model for sexual selection imported the concept of conformity. Using this model we try an environment where male agents and female agents are existed, we find that periodic phenomena of fashion are expressed. And we report the influence of conformity and differentiation on the transition of their preferences.

Periodic table of virus capsids: implications for natural selection and design.

Science.gov (United States)

Mannige, Ranjan V; Brooks, Charles L

2010-03-04

For survival, most natural viruses depend upon the existence of spherical capsids: protective shells of various sizes composed of protein subunits. So far, general evolutionary pressures shaping capsid design have remained elusive, even though an understanding of such properties may help in rationally impeding the virus life cycle and designing efficient nano-assemblies. This report uncovers an unprecedented and species-independent evolutionary pressure on virus capsids, based on the the notion that the simplest capsid designs (or those capsids with the lowest "hexamer complexity", C(h)) are the fittest, which was shown to be true for all available virus capsids. The theories result in a physically meaningful periodic table of virus capsids that uncovers strong and overarching evolutionary pressures, while also offering geometric explanations to other capsid properties (rigidity, pleomorphy, auxiliary requirements, etc.) that were previously considered to be unrelatable properties of the individual virus. Apart from describing a universal rule for virus capsid evolution, our work (especially the periodic table) provides a language with which highly diverse virus capsids, unified only by geometry, may be described and related to each other. Finally, the available virus structure databases and other published data reiterate the predicted geometry-derived rules, reinforcing the role of geometry in the natural selection and design of virus capsids.

Rats free to select between pure protein and a fat-carbohydrate mix ingest high-protein mixed meals during the dark period and protein meals during the light period.

Science.gov (United States)

Makarios-Lahham, Lina; Roseau, Suzanne M; Fromentin, Gilles; Tome, Daniel; Even, Patrick C

2004-03-01

Rats that are allowed to select their diets [dietary self- selection (DSS)] often ingest >30% of their daily energy in the form of protein. Such an intake may seem unhealthy, but the consistency of this choice suggests that it is motivated by physiologic drives. To gain a clearer understanding of how protein selection is structured during DSS, we adapted 12 rats to a standard diet (14% Protein) and then allowed them to choose between two diets, i.e., total milk protein (P) and a mix of carbohydrates and lipids (FC). The protein intake during DSS rose above 40%; assuming an intermeal interval of 10 min, 70% of the energy intake occurred with meals that included both P and FC, with the sequence of FC followed by P preferred to the sequence of P followed by FC (70 vs. 30%, P energy intake during the light period was reduced to only 10% of the daily energy intake [vs. 30% with the control P14 diet or a with a high-protein diet (50%)], and 90% of the intake was in the form of pure protein meals. In complementary studies, we verified that the high protein intake also occurred when rats were offered casein and whey and was not due to the high palatability of the milk protein. We conclude that a specific feeding pattern accompanies high protein intake in rats allowed DSS. The mechanisms underlying this behavior and its potential beneficial/adverse consequences over the long term still must be clarified.

Selection of strategy for electric power engineering development in Russia for period up to 2015

International Nuclear Information System (INIS)

Khainson, Ya.I.; Mirkovskaya, R.E.; Artem'eva, N.Yu.

1993-01-01

The result of studies, in which an attempt to select a number of real versions for development of electric power engineering for the period up to 2015, as well as to evaluate, compare and select essentially stable trends is made, are discussed. It is shown that these trends remain actual even under market economics conditions. The necessity is emphasized for creation and introduction of new generation of units and electric power plants ecologically clean, reliable and operating in wide unit capacity range. Special attention should be paid to creation of new types of NPPs, underground NPPs as well as low-and intermediate-capacity NPPs necessary for many regions of the country

Evolution of periodicity in periodical cicadas.

Science.gov (United States)

Ito, Hiromu; Kakishima, Satoshi; Uehara, Takashi; Morita, Satoru; Koyama, Takuya; Sota, Teiji; Cooley, John R; Yoshimura, Jin

2015-09-14

Periodical cicadas (Magicicada spp.) in the USA are famous for their unique prime-numbered life cycles of 13 and 17 years and their nearly perfectly synchronized mass emergences. Because almost all known species of cicada are non-periodical, periodicity is assumed to be a derived state. A leading hypothesis for the evolution of periodicity in Magicicada implicates the decline in average temperature during glacial periods. During the evolution of periodicity, the determinant of maturation in ancestral cicadas is hypothesized to have switched from size dependence to time (period) dependence. The selection for the prime-numbered cycles should have taken place only after the fixation of periodicity. Here, we build an individual-based model of cicadas under conditions of climatic cooling to explore the fixation of periodicity. In our model, under cold environments, extremely long juvenile stages lead to extremely low adult densities, limiting mating opportunities and favouring the evolution of synchronized emergence. Our results indicate that these changes, which were triggered by glacial cooling, could have led to the fixation of periodicity in the non-periodical ancestors.

Women's Suggestions for Improving Midwifery Care in The Netherlands.

Science.gov (United States)

Baas, Carien I; Erwich, Jan Jaap H M; Wiegers, Therese A; de Cock, T Paul; Hutton, Eileen K

2015-12-01

The experience of the care a woman receives during pregnancy and childbirth has an immediate and long-lasting effect on her well being. The involvement of patients and clients in health care has increased over the last decades. The Dutch maternity care system offers an excellent opportunity to explore and involve women's suggestions for the improvement of midwifery care in the current maternity care model. This qualitative study is part of the "DELIVER" study. Clients were recruited from 20 midwifery practices. Purposive sampling was used to select the practices. The clients received up to three questionnaires, in which they could respond to the question; "Do you have any suggestions on how your midwife could improve his/her provision of care?" The answers were analyzed with a qualitative thematic content analysis, using the software program MAXQDA. Altogether, 3,499 answers were provided. One overarching concept emerged: clients' desire for individualized care. Within this concept, suggestions could be clustered around 1) provider characteristics: interpersonal skills, communication, and competence, and 2) service characteristics: content and quantity of care, guidance and support, continuity of care provider, continuity of care, information, and coordination of care. Informed by the suggestions of women, care to women and their families could be improved by the following: 1) more continuity of the care provider during the prenatal, natal, and postnatal periods, 2) more information and information specifically tailored for the person, 3) client-centered communication, and 4) a personal approach with 5) enough time spent per client. © 2015 Wiley Periodicals, Inc.

Likelihood analysis of the chalcone synthase genes suggests the role of positive selection in morning glories (Ipomoea).

Science.gov (United States)

Yang, Ji; Gu, Hongya; Yang, Ziheng

2004-01-01

Chalcone synthase (CHS) is a key enzyme in the biosynthesis of flavonoides, which are important for the pigmentation of flowers and act as attractants to pollinators. Genes encoding CHS constitute a multigene family in which the copy number varies among plant species and functional divergence appears to have occurred repeatedly. In morning glories (Ipomoea), five functional CHS genes (A-E) have been described. Phylogenetic analysis of the Ipomoea CHS gene family revealed that CHS A, B, and C experienced accelerated rates of amino acid substitution relative to CHS D and E. To examine whether the CHS genes of the morning glories underwent adaptive evolution, maximum-likelihood models of codon substitution were used to analyze the functional sequences in the Ipomoea CHS gene family. These models used the nonsynonymous/synonymous rate ratio (omega = d(N)/ d(S)) as an indicator of selective pressure and allowed the ratio to vary among lineages or sites. Likelihood ratio test suggested significant variation in selection pressure among amino acid sites, with a small proportion of them detected to be under positive selection along the branches ancestral to CHS A, B, and C. Positive Darwinian selection appears to have promoted the divergence of subfamily ABC and subfamily DE and is at least partially responsible for a rate increase following gene duplication.

Multi-Period Mean-Variance Portfolio Selection with Uncertain Time Horizon When Returns Are Serially Correlated

Directory of Open Access Journals (Sweden)

Ling Zhang

2012-01-01

Full Text Available We study a multi-period mean-variance portfolio selection problem with an uncertain time horizon and serial correlations. Firstly, we embed the nonseparable multi-period optimization problem into a separable quadratic optimization problem with uncertain exit time by employing the embedding technique of Li and Ng (2000. Then we convert the later into an optimization problem with deterministic exit time. Finally, using the dynamic programming approach, we explicitly derive the optimal strategy and the efficient frontier for the dynamic mean-variance optimization problem. A numerical example with AR(1 return process is also presented, which shows that both the uncertainty of exit time and the serial correlations of returns have significant impacts on the optimal strategy and the efficient frontier.

Periodic feedback stabilization for linear periodic evolution equations

CERN Document Server

Wang, Gengsheng

2016-01-01

This book introduces a number of recent advances regarding periodic feedback stabilization for linear and time periodic evolution equations. First, it presents selected connections between linear quadratic optimal control theory and feedback stabilization theory for linear periodic evolution equations. Secondly, it identifies several criteria for the periodic feedback stabilization from the perspective of geometry, algebra and analyses respectively. Next, it describes several ways to design periodic feedback laws. Lastly, the book introduces readers to key methods for designing the control machines. Given its coverage and scope, it offers a helpful guide for graduate students and researchers in the areas of control theory and applied mathematics.

Select phytochemicals suppress human T-lymphocytes and mouse splenocytes suggesting their use in autoimmunity and transplantation

Science.gov (United States)

Hushmendy, Shazaan; Jayakumar, Lalithapriya; Hahn, Amy B.; Bhoiwala, Devang; Bhoiwala, Dipti L.; Crawford, Dana R.

2009-01-01

We have considered a novel “rational” gene targeting approach for treating pathologies whose genetic bases are defined using select phytochemicals. We reason that one such potential application of this approach would be conditions requiring immunosuppression such as autoimmune disease and transplantation, where the genetic target is clearly defined; i.e., interleukin-2 and associated T-cell activation. Therefore, we hypothesized that select phytochemicals can suppress T-lymphocyte proliferation both in vitro and in vivo. The immunosuppressive effects of berry extract, curcumin, quercetin, sulforaphane, epigallocatechin gallate (EGCG), resveratrol, α-tocopherol, vitamin C and sucrose were tested on anti-CD3 plus anti-CD28-activated primary human T-lymphocytes in culture. Curcumin, sulforaphane, quercetin, berry extract and EGCG all significantly inhibited T-cell proliferation, and this effect was not due to toxicity. IL-2 production was also reduced by these agents, implicating this important T-cell cytokine in proliferation suppression. Except for berry extract, these same agents also inhibited mouse splenic T-cell proliferation and IL-2 production. Subsequent in vivo studies revealed that quercetin (but not sulforaphane) modestly suppressed mouse splenocyte proliferation following supplementation of BALB/c mice diets. This effect was especially prominent if corrected for the loss of supplement “recall” as observed in cultured T-cells. These results suggest the potential use of these select phytochemicals for treating autoimmune and transplant patients, and support our strategy of using select phytochemicals to treat genetically-defined pathologies, an approach that we believe is simple, healthy, and cost-effective. PMID:19761891

Predictive Studies Suggest that the Risk for the Selection of Antibiotic Resistance by Biocides Is Likely Low in Stenotrophomonas maltophilia.

Directory of Open Access Journals (Sweden)

María Blanca Sánchez

Full Text Available Biocides are used without restriction for several purposes. As a consequence, large amounts of biocides are released without any control in the environment, a situation that can challenge the microbial population dynamics, including selection of antibiotic resistant bacteria. Previous work has shown that triclosan selects Stenotrophomonas maltophilia antibiotic resistant mutants overexpressing the efflux pump SmeDEF and induces expression of this pump triggering transient low-level resistance. In the present work we analyze if two other common biocides, benzalkonium chloride and hexachlorophene, trigger antibiotic resistance in S. maltophilia. Bioinformatic and biochemical methods showed that benzalkonium chloride and hexachlorophene bind the repressor of smeDEF, SmeT. Only benzalkonium chloride triggers expression of smeD and its effect in transient antibiotic resistance is minor. None of the hexachlorophene-selected mutants was antibiotic resistant. Two benzalkonium chloride resistant mutants presented reduced susceptibility to antibiotics and were impaired in growth. Metabolic profiling showed they were more proficient than their parental strain in the use of some dipeptides. We can then conclude that although bioinformatic predictions and biochemical studies suggest that both hexachlorophene and benzalkonium chloride should induce smeDEF expression leading to transient S. maltophilia resistance to antibiotics, phenotypic assays showed this not to be true. The facts that hexachlorophene resistant mutants are not antibiotic resistant and that the benzalkonium chloride resistant mutants presenting altered susceptibility to antibiotics were impaired in growth suggests that the risk for the selection (and fixation of S. maltophilia antibiotic resistant mutants by these biocides is likely low, at least in the absence of constant selection pressure.

Atypical auditory refractory periods in children from lower socio-economic status backgrounds: ERP evidence for a role of selective attention.

Science.gov (United States)

Stevens, Courtney; Paulsen, David; Yasen, Alia; Neville, Helen

2015-02-01

Previous neuroimaging studies indicate that lower socio-economic status (SES) is associated with reduced effects of selective attention on auditory processing. Here, we investigated whether lower SES is also associated with differences in a stimulus-driven aspect of auditory processing: the neural refractory period, or reduced amplitude response at faster rates of stimulus presentation. Thirty-two children aged 3 to 8 years participated, and were divided into two SES groups based on maternal education. Event-related brain potentials were recorded to probe stimuli presented at interstimulus intervals (ISIs) of 200, 500, or 1000 ms. These probes were superimposed on story narratives when attended and ignored, permitting a simultaneous experimental manipulation of selective attention. Results indicated that group differences in refractory periods differed as a function of attention condition. Children from higher SES backgrounds showed full neural recovery by 500 ms for attended stimuli, but required at least 1000 ms for unattended stimuli. In contrast, children from lower SES backgrounds showed similar refractory effects to attended and unattended stimuli, with full neural recovery by 500 ms. Thus, in higher SES children only, one functional consequence of selective attention is attenuation of the response to unattended stimuli, particularly at rapid ISIs, altering basic properties of the auditory refractory period. Together, these data indicate that differences in selective attention impact basic aspects of auditory processing in children from lower SES backgrounds. Copyright © 2013 Elsevier B.V. All rights reserved.

Diversifying selection and functional analysis of interleukin-4 suggests antagonism-driven evolution at receptor-binding interfaces

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Brown Scott

2010-07-01

Full Text Available Abstract Background Interleukin-4 (IL4 is a secreted immunoregulatory cytokine critically involved in host protection from parasitic helminths 1. Reasoning that helminths may have evolved mechanisms to antagonize IL4 to maximize their dispersal, we explored mammalian IL4 evolution. Results This analysis revealed evidence of diversifying selection at 15 residues, clustered in epitopes responsible for IL4 binding to its Type I and Type II receptors. Such a striking signature of selective pressure suggested either recurrent episodes of pathogen antagonism or ligand/receptor co-evolution. To test the latter possibility, we performed detailed functional analysis of IL4 allotypes expressed by Mus musculus musculus and Mus musculus castaneus, which happen to differ at 5 residues (including three at positively selected sites in and adjacent to the site 1 epitope that binds the IL4Rα subunit shared by the Type I and Type II IL4 receptors. We show that this intra-species variation affects the ability of IL4 neither to bind IL4 receptor alpha (IL4Rα nor to signal biological responses through its Type I receptor. Conclusions Our results -- reminiscent of clustered positively selected sites revealing functionally important residues at host-virus interaction interfaces -- are consistent with IL4 having evolved to avoid recurrent pathogen antagonism, while maintaining the capacity to bind and signal through its cognate receptor. This work exposes what may be a general feature of evolutionary conflicts fought by pathogen antagonists at host protein-protein interaction interfaces involved in immune signaling: the emergence of receptor-binding ligand epitopes capable of buffering amino acid variation.

Waterfowl habitat use and selection during the remigial moult period in the northern hemisphere

Science.gov (United States)

Fox, Anthony D.; Flint, Paul L.; Hohman, William L.; Savard, Jean-Pierre L.

2014-01-01

This paper reviews factors affecting site selection amongst waterfowl (Anatidae) during the flightless remigial moult, emphasising the roles of predation and food supply (especially protein and energy). The current literature suggests survival during flightless moult is at least as high as at other times of the annual cycle, but documented cases of predation of flightless waterfowl under particular conditions lead us to infer that habitat selection is generally highly effective in mitigating or avoiding predation. High energetic costs of feather replacement and specific amino-acid requirements for their construction imply adoption of special energetic and nutritional strategies at a time when flightlessness limits movements. Some waterfowl meet their energy needs from endogenous stores accumulated prior to remigial moult, others rely on exogenous supply, but this varies with species, age, reproductive status and site. Limited evidence suggests feather proteins are derived from endogenous and exogenous sources which may affect site selection. Remigial moult does not occur independently of other annual cycle events and is affected by reproductive investment and success. Hence, moult strategies are affected by age, sex and reproductive history, and may be influenced by the need to attain a certain internal state for the next stage in the annual cycle (e.g. autumn migration). We know little about habitat selection during moult and urge more research of this poorly known part of the annual cycle, with particular emphasis on identifying key concentrations and habitats for specific flyway populations and the effects of disturbance upon these. This knowledge will better inform conservation actions and management actions concerning waterfowl during moult and the habitats that they exploit.

The Effects of Suggestibility on Relaxation.

Science.gov (United States)

Rickard, Henry C.; And Others

1985-01-01

Selected undergraduates (N=32) on the basis of Creative Imagination Scale scores and randomly assigned high and low suggestibility subjects to progressive relaxation (PR) and suggestions of relaxation (SR) training modes. Results revealed a significant pre-post relaxation effect, and main efffects for both suggestibility and training mode. (NRB)

Life at extreme conditions: neutron scattering studies of biological molecules suggest that evolution selected dynamics

International Nuclear Information System (INIS)

Zaccai, Joseph Giuseppe

2008-01-01

The short review concentrates on recent work performed at the neutrons in biology laboratories of the Institut Laue Langevin and Institut de Biologie Structurale in Grenoble. Extremophile organisms have been discovered that require extreme conditions of temperature, pressure or solvent environment for survival. The existence of such organisms poses a significant challenge in understanding the physical chemistry of their proteins, in view of the great sensitivity of protein structure and stability to the aqueous environment and to external conditions in general. Results of neutron scattering measurements on the dynamics of proteins from extremophile organisms, in vitro as well as in vivo, indicated remarkably how adaptation to extreme conditions involves forces and fluctuation amplitudes that have been selected specifically, suggesting that evolutionary macromolecular selection proceeded via dynamics. The experiments were performed on a halophilic protein, and membrane adapted to high salt, a thermophilic enzyme adapted to high temperature and its mesophilic (adapted to 37 degC) homologue; and in vivo for psychrophilic, mesophilic, thermophilic and hyperthermophilic bacteria, adapted respectively to temperatures of 4 degC, 37 degC, 75 degC and 85 degC. Further work demonstrated the existence of a water component of exceptionally low mobility in an extreme halophile from the Dead Sea, which is not present in mesophile bacterial cells. (author)

Selective hedging strategies for oil stockpiling

International Nuclear Information System (INIS)

Yun, Won-Cheol

2006-01-01

As a feasible option for improving the economics and operational efficiency of stockpiling by public agency, this study suggests simple selective hedging strategies using forward contracts. The main advantage of these selective hedging strategies over the previous ones is not to predict future spot prices, but to utilize the sign and magnitude of basis easily available to the public. Using the weekly spot and forward prices of West Texas Intermediate for the period of October 1997-August 2002, this study adopts an ex ante out-of-sample analysis to examine selective hedging performances compared to no-hedge and minimum-variance routine hedging strategies. To some extent, selective hedging strategies dominate the traditional routine hedging strategy, but do not improve upon the expected returns of no-hedge case, which is mainly due to the data characteristics of out-of-sample period used in this analysis

Semantic Wavelet-Induced Frequency-Tagging (SWIFT Periodically Activates Category Selective Areas While Steadily Activating Early Visual Areas.

Directory of Open Access Journals (Sweden)

Roger Koenig-Robert

Full Text Available Primate visual systems process natural images in a hierarchical manner: at the early stage, neurons are tuned to local image features, while neurons in high-level areas are tuned to abstract object categories. Standard models of visual processing assume that the transition of tuning from image features to object categories emerges gradually along the visual hierarchy. Direct tests of such models remain difficult due to confounding alteration in low-level image properties when contrasting distinct object categories. When such contrast is performed in a classic functional localizer method, the desired activation in high-level visual areas is typically accompanied with activation in early visual areas. Here we used a novel image-modulation method called SWIFT (semantic wavelet-induced frequency-tagging, a variant of frequency-tagging techniques. Natural images modulated by SWIFT reveal object semantics periodically while keeping low-level properties constant. Using functional magnetic resonance imaging (fMRI, we indeed found that faces and scenes modulated with SWIFT periodically activated the prototypical category-selective areas while they elicited sustained and constant responses in early visual areas. SWIFT and the localizer were selective and specific to a similar extent in activating category-selective areas. Only SWIFT progressively activated the visual pathway from low- to high-level areas, consistent with predictions from standard hierarchical models. We confirmed these results with criterion-free methods, generalizing the validity of our approach and show that it is possible to dissociate neural activation in early and category-selective areas. Our results provide direct evidence for the hierarchical nature of the representation of visual objects along the visual stream and open up future applications of frequency-tagging methods in fMRI.

Periodic imidazolium-bridged hybrid monolith for high-efficiency capillary liquid chromatography with enhanced selectivity.

Science.gov (United States)

Qiao, Xiaoqiang; Zhang, Niu; Han, Manman; Li, Xueyun; Qin, Xinying; Shen, Shigang

2017-03-01

A novel periodic imidazolium-bridged hybrid monolithic column was developed. With diene imidazolium ionic liquid 1-allyl-3-vinylimidazolium bromide as both cross-linker and organic functionalized reagent, a new periodic imidazolium-bridged hybrid monolithic column was facilely prepared in capillary with homogeneously distributed cationic imidazolium by a one-step free-radical polymerization with polyhedral oligomeric silsesquioxane methacryl substituted. The successful preparation of the new column was verified by Fourier transform infrared spectroscopy, scanning electron microscopy, elemental analysis, and surface area analysis. Most interestingly, the bonded amount of 1-allyl-3-vinylimidazolium bromide of the new column is three times higher than that of the conventional imidazolium-embedded hybrid monolithic column and the specific surface area of the column reached 478 m 2 /g. The new column exhibited high stability, excellent separation efficiency, and enhanced separation selectivity. The column efficiency reached 151 000 plates/m for alkylbenzenes. Furthermore, the new column was successfully used for separation of highly polar nucleosides and nucleic acid bases with pure water as mobile phase and even bovine serum albumin tryptic digest. All these results demonstrate the periodic imidazolium-bridged hybrid monolithic column is a good separation media and can be used for chromatographic separation of small molecules and complex biological samples with high efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

6-year periodicity and variable synchronicity in a mass-flowering plant.

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Satoshi Kakishima

Full Text Available Periodical organisms, such as bamboos and periodical cicadas, are very famous for their synchronous reproduction. In bamboos and other periodical plants, the synchronicity of mass-flowering and withering has been often reported indicating these species are monocarpic (semelparous species. Therefore, synchronicity and periodicity are often suspected to be fairly tightly coupled traits in these periodical plants. We investigate the periodicity and synchronicity of Strobilanthes flexicaulis, and a closely related species S. tashiroi on Okinawa Island, Japan. The genus Strobilanthes is known for several periodical species. Based on 32-year observational data, we confirmed that S. flexicaulis is 6-year periodical mass-flowering monocarpic plant. All the flowering plants had died after flowering. In contrast, we found that S. tashiroi is a polycarpic perennial with no mass-flowering from three-year individual tracking. We also surveyed six local populations of S. flexicaulis and found variation in the synchronicity from four highly synchronized populations (>98% of plants flowering in the mass year to two less synchronized one with 11-47% of plants flowering before and after the mass year. This result might imply that synchrony may be selected for when periodicity is established in monocarpic species. We found the selective advantages for mass-flowering in pollinator activities and predator satiation. The current results suggest that the periodical S. flexicaulis might have evolved periodicity from a non-periodical close relative. The current report should become a key finding for understanding the evolution of periodical plants.

Multi-period fuzzy mean-semi variance portfolio selection problem with transaction cost and minimum transaction lots using genetic algorithm

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Mohammad Ali Barati

2016-04-01

Full Text Available Multi-period models of portfolio selection have been developed in the literature with respect to certain assumptions. In this study, for the first time, the portfolio selection problem has been modeled based on mean-semi variance with transaction cost and minimum transaction lots considering functional constraints and fuzzy parameters. Functional constraints such as transaction cost and minimum transaction lots were included. In addition, the returns on assets parameters were considered as trapezoidal fuzzy numbers. An efficient genetic algorithm (GA was designed, results were analyzed using numerical instances and sensitivity analysis were executed. In the numerical study, the problem was solved based on the presence or absence of each mode of constraints including transaction costs and minimum transaction lots. In addition, with the use of sensitivity analysis, the results of the model were presented with the variations of minimum expected rate of programming periods.

Selection of doublet cellular patterns in directional solidification through spatially periodic perturbations

International Nuclear Information System (INIS)

Losert, W.; Stillman, D.A.; Cummins, H.Z.; Kopczynski, P.; Rappel, W.; Karma, A.

1998-01-01

Pattern formation at the solid-liquid interface of a growing crystal was studied in directional solidification using a perturbation technique. We analyzed both experimentally and numerically the stability range and dynamical selection of cellular arrays of 'doublets' with asymmetric tip shapes, separated by alternate deep and shallow grooves. Applying an initial periodic perturbation of arbitrary wavelength to the unstable planar interface allowed us to force the interface to evolve into doublet states that would not otherwise be dynamically accessible from a planar interface. We determined systematically the ranges of wavelength corresponding to stable singlets, stable doublets, and transient unstable patterns. Experimentally, this was accomplished by applying a brief UV light pulse of a desired spatial periodicity to the planar interface during the planar-cellular transient using the model alloy Succinonitrile-Coumarin 152. Numerical simulations of the nonlinear evolution of the interface were performed starting from a small sinusoidal perturbation of the steady-state planar interface. These simulations were carried out using a computationally efficient phase-field symmetric model of directional solidification with recently reformulated asymptotics and vanishing kinetics [A. Karma and W.-J. Rappel, Phys. Rev. E 53 R3017 (1996); Phys. Rev. Lett. 77, 4050 (1996); Phys. Rev. E 57, 4323 (1998)], which allowed us to simulate spatially extended arrays that can be meaningfully compared to experiments. Simulations and experiments show remarkable qualitative agreement in the dynamic evolution, steady-state structure, and instability mechanisms of doublet cellular arrays. copyright 1998 The American Physical Society

Model selection approach suggests causal association between 25-hydroxyvitamin D and colorectal cancer.

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Lina Zgaga

Full Text Available Vitamin D deficiency has been associated with increased risk of colorectal cancer (CRC, but causal relationship has not yet been confirmed. We investigate the direction of causation between vitamin D and CRC by extending the conventional approaches to allow pleiotropic relationships and by explicitly modelling unmeasured confounders.Plasma 25-hydroxyvitamin D (25-OHD, genetic variants associated with 25-OHD and CRC, and other relevant information was available for 2645 individuals (1057 CRC cases and 1588 controls and included in the model. We investigate whether 25-OHD is likely to be causally associated with CRC, or vice versa, by selecting the best modelling hypothesis according to Bayesian predictive scores. We examine consistency for a range of prior assumptions.Model comparison showed preference for the causal association between low 25-OHD and CRC over the reverse causal hypothesis. This was confirmed for posterior mean deviances obtained for both models (11.5 natural log units in favour of the causal model, and also for deviance information criteria (DIC computed for a range of prior distributions. Overall, models ignoring hidden confounding or pleiotropy had significantly poorer DIC scores.Results suggest causal association between 25-OHD and colorectal cancer, and support the need for randomised clinical trials for further confirmations.

Medicine in Balkans during the Roman Period.

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Baykan, Daniş

2017-08-04

The aim of this study is to investigate the archaeological finds to enlighten the medical methods of treatments and operations applied in Balkans during Roman Period. Some independent local and regional find groups, taken from existing publications will be grouped together and a holistic point-of-view will be taken against medicine in Balkan Geography during Roman Period. Due to basic differences it contained, the data before Roman Period are excluded. Most of Greece and Aegean Islands are also excluded since the topic selected is "Medicine of Roman Period." Greece and Aegean Islands should be evaluated in another study in connection with West Anatolia which is closer than the Balkan Geography in terms of social relations. The spread of medical tools in Balkans during Roman Period is concentrated around military garrisons, and in settlements built around military pathways, and in settlements containing an amphitheater associated with gladiators. This spread is verified by the studies on Bulgaria in general. The data is also compatible with the assertion suggesting that the amount of application of pharmaceutical treatment increases when one moves away from the military centres.

"Boom" and "Bust" cycles in virus growth suggest multiple selective forces in influenza a evolution

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Marquart Mary E

2011-04-01

Full Text Available Abstract Background Influenza A virus evolution in humans is driven at least in part by mutations allowing the virus to escape antibody neutralization. Little is known about the evolution of influenza in birds, a major reservoir of influenza A. Methods Neutralizing polyclonal antiserum was raised in chicken against reassortant influenza virus, CalX, bearing the hemagglutinin (HA and neuraminidase (NA of A/California/7/2004 [H3N2]. CalX was serially passaged in the presence of anti-CalX polyclonal IgY to derive viruses capable of growth in the presence of antibody. Results Polyclonal chicken antibody neutralized both HA activity and infection by CalX, but had no effect on a strain bearing an earlier human H3 and an irrelevant neuraminidase (A/Memphis/71-Bellamy/42 [H3N1]. Surprisingly, most of the antibody-resistant viruses were still at least partially sensitive to neutralization of HA activity and viral infection. Although mutant HA genes bearing changes that might affect antibody neutralization were identified, the vast majority of HA sequences obtained were identical to wild type, and no individual mutant sequence was found in more than one passage, suggesting that those mutations that were observed did not confer sufficient selective advantage to come to dominate the population. Different passages yielded infectious foci of varying size and plaques of varying size and morphology. Yields of infectious virus and relative frequency of different morphologies changed markedly from passage to passage. Sequences of bulk, uncloned PCR products from antibody-resistant passages indicated changes in the PB2 and PA proteins with respect to the wild type virus. Conclusions Each antibody-selected passage consisted of a variety of different cocirculating populations, rather than pure populations of virus able to escape antibody by changes in antibody epitopes. The ability to escape antibody is apparently due to changes in genes encoding the viral

Periodical rocking long period gratings in PANDA fibers for high temperature and refractive index sensing

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Jin, Wa; Bi, Wei-hong; Fu, Xing-hu; Fu, Guang-wei

2017-09-01

We report periodical rocking long period gratings (PR-LPGs) in PANDA fibers fabricated with CO2 laser. The PR-LPGs achieve very high coupling efficiency of 19 dB with 12 periods and a 3.5° twist angle in just one scanning cycle, which is much more effective than the conventional CO2 laser fabrication technique. This type of LPGs exhibits polarization-selective resonance dips which demonstrate different sensitivities to environmental parameters. The high temperature and external refractive index sensitivities are measured simultaneously, so it can be used as a wavelength-selective polarization filter and sensor.

Periparturient Period in Terms of Body Condition Score and Selected Parameters of Hormonal Profiles

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Vargová M.

2016-03-01

Full Text Available The majority of all diseases in dairy cows occur during the period from three weeks before parturition to three weeks after parturition, in the periparturient or transitional period. The objective of this study was to evaluate the dynamics of selected parameters of: the hormonal profiles, the body condition score (BCS and their interrelationships. The study was carried out on 15 dairy cows of the Slovak Pied Cattle, from three weeks before to nine weeks after parturition, which were divided into six groups. The concentrations of leptin during ante partum increased from 23.08 ± 10.58 ng.ml−1 to 26.80 ± 11.47 ng.ml−1, then gradually decreased (P > 0.05, and conversely, the concentrations of ghrelin before parturition were found to be decreasing and during the postpartal period, the concentrations increased, with the highest value of 35.94 ± 16.85 pg.ml−1. In the case of insulin, we found the opposite tendency of ghrelin. We observed significantly higher values of BCS in dry cows than in cows after parturition (P < 0.001. Comparing the BCS and the parameter of the hormonal profiles, we found both positive and negative correlations: leptin and ghrelin (r = −0.235, P < 0.05, and BCS and insulin (r = 0.232, P < 0.05, and BCS and leptin (r = 0.360, P < 0.001. The interrelationships between the hormones and the body condition score, provided evidence that the variations in concentrations of leptin, ghrelin and insulin were related to variations in the BCS.

CRISPR distribution within the Escherichia coli species is not suggestive of immunity-associated diversifying selection.

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Touchon, Marie; Charpentier, Sophie; Clermont, Olivier; Rocha, Eduardo P C; Denamur, Erick; Branger, Catherine

2011-05-01

In order to get further insights into the role of the clustered, regularly interspaced, short palindromic repeats (CRISPRs) in Escherichia coli, we analyzed the CRISPR diversity in a collection of 290 strains, in the phylogenetic framework of the strains represented by multilocus sequence typing (MLST). The set included 263 natural E. coli isolates exposed to various environments and isolated over a 20-year period from humans and animals, as well as 27 fully sequenced strains. Our analyses confirm that there are two largely independent pairs of CRISPR loci (CRISPR1 and -2 and CRISPR3 and -4), each associated with a different type of cas genes (Ecoli and Ypest, respectively), but that each pair of CRISPRs has similar dynamics. Strikingly, the major phylogenetic group B2 is almost devoid of CRISPRs. The majority of genomes analyzed lack Ypest cas genes and contain CRISPR3 with spacers matching Ypest cas genes. The analysis of relatedness between strains in terms of spacer repertoire and the MLST tree shows a pattern where closely related strains (MLST phylogenetic distance of 0.01) exhibit completely different CRISPRs. This suggests rare but radical turnover of spacers in CRISPRs rather than CRISPR gradual change. We found no link between the presence, size, or content of CRISPRs and the lifestyle of the strains. Our data suggest that, within the E. coli species, CRISPRs do not have the expected characteristics of a classical immune system.

Selective propagation of mouse-passaged scrapie prions with long incubation period from a mixed prion population using GT1-7 cells.

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Kohtaro Miyazawa

Full Text Available In our previous study, we demonstrated the propagation of mouse-passaged scrapie isolates with long incubation periods (L-type derived from natural Japanese sheep scrapie cases in murine hypothalamic GT1-7 cells, along with disease-associated prion protein (PrPSc accumulation. We here analyzed the susceptibility of GT1-7 cells to scrapie prions by exposure to infected mouse brains at different passages, following interspecies transmission. Wild-type mice challenged with a natural sheep scrapie case (Kanagawa exhibited heterogeneity of transmitted scrapie prions in early passages, and this mixed population converged upon one with a short incubation period (S-type following subsequent passages. However, when GT1-7 cells were challenged with these heterologous samples, L-type prions became dominant. This study demonstrated that the susceptibility of GT1-7 cells to L-type prions was at least 105 times higher than that to S-type prions and that L-type prion-specific biological characteristics remained unchanged after serial passages in GT1-7 cells. This suggests that a GT1-7 cell culture model would be more useful for the economical and stable amplification of L-type prions at the laboratory level. Furthermore, this cell culture model might be used to selectively propagate L-type scrapie prions from a mixed prion population.

AFLP genome scans suggest divergent selection on colour patterning in allopatric colour morphs of a cichlid fish.

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Mattersdorfer, Karin; Koblmüller, Stephan; Sefc, Kristina M

2012-07-01

Genome scan-based tests for selection are directly applicable to natural populations to study the genetic and evolutionary mechanisms behind phenotypic differentiation. We conducted AFLP genome scans in three distinct geographic colour morphs of the cichlid fish Tropheus moorii to assess whether the extant, allopatric colour pattern differentiation can be explained by drift and to identify markers mapping to genomic regions possibly involved in colour patterning. The tested morphs occupy adjacent shore sections in southern Lake Tanganyika and are separated from each other by major habitat barriers. The genome scans revealed significant genetic structure between morphs, but a very low proportion of loci fixed for alternative AFLP alleles in different morphs. This high level of polymorphism within morphs suggested that colour pattern differentiation did not result exclusively from neutral processes. Outlier detection methods identified six loci with excess differentiation in the comparison between a bluish and a yellow-blotch morph and five different outlier loci in comparisons of each of these morphs with a red morph. As population expansions and the genetic structure of Tropheus make the outlier approach prone to false-positive signals of selection, we examined the correlation between outlier locus alleles and colour phenotypes in a genetic and phenotypic cline between two morphs. Distributions of allele frequencies at one outlier locus were indeed consistent with linkage to a colour locus. Despite the challenges posed by population structure and demography, our results encourage the cautious application of genome scans to studies of divergent selection in subdivided and recently expanded populations. © 2012 Blackwell Publishing Ltd.

Levels and patterns of nucleotide variation in domestication QTL regions on rice chromosome 3 suggest lineage-specific selection.

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Xianfa Xie

Full Text Available Oryza sativa or Asian cultivated rice is one of the major cereal grass species domesticated for human food use during the Neolithic. Domestication of this species from the wild grass Oryza rufipogon was accompanied by changes in several traits, including seed shattering, percent seed set, tillering, grain weight, and flowering time. Quantitative trait locus (QTL mapping has identified three genomic regions in chromosome 3 that appear to be associated with these traits. We would like to study whether these regions show signatures of selection and whether the same genetic basis underlies the domestication of different rice varieties. Fragments of 88 genes spanning these three genomic regions were sequenced from multiple accessions of two major varietal groups in O. sativa--indica and tropical japonica--as well as the ancestral wild rice species O. rufipogon. In tropical japonica, the levels of nucleotide variation in these three QTL regions are significantly lower compared to genome-wide levels, and coalescent simulations based on a complex demographic model of rice domestication indicate that these patterns are consistent with selection. In contrast, there is no significant reduction in nucleotide diversity in the homologous regions in indica rice. These results suggest that there are differences in the genetic and selective basis for domestication between these two Asian rice varietal groups.

The importance of protein in leaf selection of folivorous primates.

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Ganzhorn, Joerg U; Arrigo-Nelson, Summer J; Carrai, Valentina; Chalise, Mukesh K; Donati, Giuseppe; Droescher, Iris; Eppley, Timothy M; Irwin, Mitchell T; Koch, Flávia; Koenig, Andreas; Kowalewski, Martin M; Mowry, Christopher B; Patel, Erik R; Pichon, Claire; Ralison, Jose; Reisdorff, Christoph; Simmen, Bruno; Stalenberg, Eleanor; Starrs, Danswell; Terboven, Juana; Wright, Patricia C; Foley, William J

2017-04-01

Protein limitation has been considered a key factor in hypotheses on the evolution of life history and animal communities, suggesting that animals should prioritize protein in their food choice. This contrasts with the limited support that food selection studies have provided for such a priority in nonhuman primates, particularly for folivores. Here, we suggest that this discrepancy can be resolved if folivores only need to select for high protein leaves when average protein concentration in the habitat is low. To test the prediction, we applied meta-analyses to analyze published and unpublished results of food selection for protein and fiber concentrations from 24 studies (some with multiple species) of folivorous primates. To counter potential methodological flaws, we differentiated between methods analyzing total nitrogen and soluble protein concentrations. We used a meta-analysis to test for the effect of protein on food selection by primates and found a significant effect of soluble protein concentrations, but a non-significant effect for total nitrogen. Furthermore, selection for soluble protein was reinforced in forests where protein was less available. Selection for low fiber content was significant but unrelated to the fiber concentrations in representative leaf samples of a given forest. There was no relationship (either negative or positive) between the concentration of protein and fiber in the food or in representative samples of leaves. Overall our study suggests that protein selection is influenced by the protein availability in the environment, explaining the sometimes contradictory results in previous studies on protein selection. Am. J. Primatol. 79:e22550, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Purine Turnover Metabolites and Selected Antioxidants in Blood of Goats during the Periparturient Period

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Ewa Skotnicka

2010-01-01

Full Text Available The aim of this study was to examine the relationships between the erythrocyte concentrations of ATP, ADP, AMP, NAD+, NADP+ and adenylate energy charge (AEC and their metabolites: inosine (Ino, hypoxanthine (Hyp, uric acid (UA, selected blood antioxidants: superoxide dismutase (SOD, glutathione reductase (GR of goats during the periparturient period. The study was conducted on 12 clinically healthy pregnant goats (Capra hircus - 75% genotype of the Polish noble white aged between 2-3 years. Blood was taken from the external jugular vein early in the morning before feeding and obtained twice (4 weeks and 1 week before delivery and twice (2 and 3 weeks after delivery. The ATP concentration did not change significantly. One week before delivery ADP, AMP and Ino concentrations were significantly higher and AEC value significantly lower compared to values in the third week after delivery (p ≤ 0.02, p ≤ 0.05, p ≤ 0.03 and p ≤ 0.01, respectively. One week before and two weeks after delivery we observed a significant increase in SOD and GR activities and an increase in NAD+ and NADP+ concentrations but a significant decrease in Hyp and UA concentrations. Constant ATP concentration and the changes in the dynamics and tendency of Hyp and UA concentrations show that in the periparturient period in goats, purine metabolism undergoes adaptive changes. The balance between resynthetic processes and adenine nucleotide degradation is retained in order to level the oxygen and energy lacks. The results of our study show that the maintenance of prooxidative homeostasis in goats of peripartal period depends mainly on enzymatic mechanisms.

State updating and calibration period selection to improve dynamic monthly streamflow forecasts for an environmental flow management application

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Gibbs, Matthew S.; McInerney, David; Humphrey, Greer; Thyer, Mark A.; Maier, Holger R.; Dandy, Graeme C.; Kavetski, Dmitri

2018-02-01

Monthly to seasonal streamflow forecasts provide useful information for a range of water resource management and planning applications. This work focuses on improving such forecasts by considering the following two aspects: (1) state updating to force the models to match observations from the start of the forecast period, and (2) selection of a shorter calibration period that is more representative of the forecast period, compared to a longer calibration period traditionally used. The analysis is undertaken in the context of using streamflow forecasts for environmental flow water management of an open channel drainage network in southern Australia. Forecasts of monthly streamflow are obtained using a conceptual rainfall-runoff model combined with a post-processor error model for uncertainty analysis. This model set-up is applied to two catchments, one with stronger evidence of non-stationarity than the other. A range of metrics are used to assess different aspects of predictive performance, including reliability, sharpness, bias and accuracy. The results indicate that, for most scenarios and metrics, state updating improves predictive performance for both observed rainfall and forecast rainfall sources. Using the shorter calibration period also improves predictive performance, particularly for the catchment with stronger evidence of non-stationarity. The results highlight that a traditional approach of using a long calibration period can degrade predictive performance when there is evidence of non-stationarity. The techniques presented can form the basis for operational monthly streamflow forecasting systems and provide support for environmental decision-making.

Rapid evolution of troglomorphic characters suggests selection rather than neutral mutation as a driver of eye reduction in cave crabs.

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Klaus, Sebastian; Mendoza, José C E; Liew, Jia Huan; Plath, Martin; Meier, Rudolf; Yeo, Darren C J

2013-04-23

This study asked whether reductive traits in cave organisms evolve at a slower pace (suggesting neutral evolution under relaxed selection) than constructive changes, which are likely to evolve under directional selection. We investigated 11 subterranean and seven surface populations of Sundathelphusa freshwater crabs on Bohol Island, Philippines, and examined constructive traits associated with improved food finding in darkness (increased leg and setae length) and reductive traits (reduced cornea size and eyestalk length). All changes occurred rapidly, given that the age of the most recent common ancestor was estimated to be 722-271 ka based on three mitochondrial markers. In order to quantify the speed of character change, we correlated the degree of morphological change with genetic distances between surface and subterranean individuals. The temporal pattern of character change following the transition to subterranean life was indistinguishable for constructive and reductive traits, characterized by an immediate onset and rapid evolutionary change. We propose that the evolution of these reductive traits-just like constructive traits-is most likely driven by strong directional selection.

Variability and changes in selected climate elements in Madrid and Alicante in the period 2000-2014

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Cielecka Katarzyna

2015-10-01

Full Text Available The aim of this study is to compare climatic conditions between the interior of the Iberian Peninsula and the southeastern coast of Spain. The article analyzes selected elements of climate over the last 15 years (2000-2014. Synoptic data from airport meteorological stations in Madrid Barajas and Alicante Elche were used. Attention was focused on annual air temperature, relative humidity and precipitation. The mean climatic conditions over the period 2000-2014 were compared with those over the 1961-1990 period which is recommended by WMO as climate normal and with data for the 1971-2000 coming from ‘Climate Atlas’ of Spanish meteorologists group AEMET. Two of climate elements discussed were characterized by significant changes. The annual air temperature was higher by about 0.2°C in Alicante and 0.9°C in Madrid in the period 2000-2014 compared to the 1961-1990. The current winters were colder than in years 1961-1990 at both stations. Gradual decrease in annual precipitation totals was observed at both stations. In 1961-1990 the annual average precipitation in Madrid amounted to 414 mm, while in Alicante it was 356 mm. However, in the recent years of 2000-2014 these totals were lower compared to 1961-1990 reaching 364.1 mm in the central part of Spain and 245.7 mm on the south-western coast.

Nest site selection by Kentish plover suggests a trade-off between nest-crypsis and predator detection strategies.

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Miguel Ángel Gómez-Serrano

Full Text Available Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of

Response to multi-generational selection under elevated [CO2] in two temperature regimes suggests enhanced carbon assimilation and increased reproductive output in Brassica napus L

DEFF Research Database (Denmark)

Frenck, Georg; van der Linden, Leon; Mikkelsen, Teis Nørgaard

2013-01-01

different temperature regimes. To reveal phenotypic divergence at the manipulated [CO2] and temperature conditions, a full-factorial natural selection regime was established in a phytotron environment over the range of four generations. It is demonstrated that a directional response to selection at elevated......Functional plant traits are likely to adapt under the sustained pressure imposed by environmental changes through natural selection. Employing Brassica napus as a model, a multi-generational study was performed to investigate the potential trajectories of selection at elevated [CO2] in two...... subjected to increased levels of CO2 over the generational range investigated. The results of this study suggest that phenotypic divergence of plants selected under elevated atmospheric CO2 concentration may drive the future functions of plant productivity to be different from projections that do...

Considerations of selection suggested for internal contamination monitoring in Cuba

International Nuclear Information System (INIS)

Cruz S, R.; Lopez B, G.; Placeres V, C.; Arado L, J.; Jova S, L.

1996-01-01

A method for calculating effective risk of radionuclide intake and hypothetical annual dose that will receive a person who works with unsealed sources is proposed. Calculated committed dose equivalent and metabolic characteristic of radionuclides permit to select the type of monitoring 'in vivo' and/or 'in vitro'. The method was applied to 396 workers from 28 institutions, where 20 radionuclides in 124 different products for 266 applications are used. From this study 62% of the workers had to be monitored for internal contamination, meanly by 'in vitro' monitoring. In practices of Nuclear Medicine and other medical uses 75% of the workers had to be monitored. These results permitted to corroborate the criteria for internal contamination monitoring program carried out by Center for Hygiene and Radiation Protection and permitted to identify needs for control of radionuclides intakes. (authors).5 refs., 3 figs

The distribution of P-values in medical research articles suggested selective reporting associated with statistical significance.

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Perneger, Thomas V; Combescure, Christophe

2017-07-01

Published P-values provide a window into the global enterprise of medical research. The aim of this study was to use the distribution of published P-values to estimate the relative frequencies of null and alternative hypotheses and to seek irregularities suggestive of publication bias. This cross-sectional study included P-values published in 120 medical research articles in 2016 (30 each from the BMJ, JAMA, Lancet, and New England Journal of Medicine). The observed distribution of P-values was compared with expected distributions under the null hypothesis (i.e., uniform between 0 and 1) and the alternative hypothesis (strictly decreasing from 0 to 1). P-values were categorized according to conventional levels of statistical significance and in one-percent intervals. Among 4,158 recorded P-values, 26.1% were highly significant (P values values equal to 1, and (3) about twice as many P-values less than 0.05 compared with those more than 0.05. The latter finding was seen in both randomized trials and observational studies, and in most types of analyses, excepting heterogeneity tests and interaction tests. Under plausible assumptions, we estimate that about half of the tested hypotheses were null and the other half were alternative. This analysis suggests that statistical tests published in medical journals are not a random sample of null and alternative hypotheses but that selective reporting is prevalent. In particular, significant results are about twice as likely to be reported as nonsignificant results. Copyright © 2017 Elsevier Inc. All rights reserved.

Retrospective analysis of necropsy reports suggestive of abuse in dogs and cats.

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Almeida, Daniel C; Torres, Sheila M F; Wuenschmann, Arno

2018-02-15

OBJECTIVE To identify historical and necropsy findings suggestive of neglect or abuse of dogs and cats by retrospective analysis of necropsy reports from a veterinary diagnostic laboratory. DESIGN Retrospective cohort study. SAMPLE 119 necropsy reports of dogs and cats. PROCEDURES Necropsy reports from February 2001 to May 2012 were electronically searched to identify potential animal abuse or neglect cases. Cases were selected and categorized according to a previously proposed method for classification of animal abuse. Inclusion criteria included signs of neglect, nonaccidental injury (NAI; blunt-force or sharp-force trauma, gunshot, burns, drowning, asphyxiation, and suspicious intoxications), and sexual abuse. Poor preservation of cadavers, age abuse cases, determined on the basis of all necropsies performed in the study period, was 73 of 8,417 (0.87%) in dogs and 46 of 4,905 (0.94%) in cats. Neglect and NAI were commonly identified in cats; NAI was most commonly found in dogs. Gunshot and blunt-force trauma were the most common NAIs in dogs and cats, respectively. Pit bull-type dogs (29/73 [40%]) were overrepresented in several abuse categories. Most cats (29/46 [63%]) were domestic shorthair, but no breed association was found. Most (41/71 [58%]) affected animals with age data available were ≤ 2 years old. CONCLUSIONS AND CLINICAL RELEVANCE Approximately 1% of dogs and cats necropsied in the study period had signs suggestive of abuse. Medical findings alone are not necessarily indicative of abuse, but some findings can increase the index of suspicion.

THEORETICAL CEPHEID PERIOD-LUMINOSITY AND PERIOD-COLOR RELATIONS IN SPITZER IRAC BANDS

International Nuclear Information System (INIS)

Ngeow, Chow-Choong; Marconi, Marcella; Musella, Ilaria; Cignoni, Michele; Kanbur, Shashsi M.

2012-01-01

In this paper, the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L relations were compared to the empirical IRAC band P-L relations recently determined from Galactic and Magellanic Clouds Cepheids. For the Galactic case, synthetic P-L relations from model sets with (Y = 0.26, Z = 0.01), (Y = 0.26, Z = 0.02), and (Y = 0.28, Z = 0.02) agree with the empirical Galactic P-L relations derived from the Hubble Space Telescope parallaxes. For Magellanic Cloud Cepheids, the synthetic P-L relations from model sets with (Y = 0.25, Z = 0.008) agree with both of the empirical Large Magellanic Cloud (LMC) and Small Magellanic Cloud P-L relations. Analysis of the synthetic P-L relations from all model sets suggested that the IRAC band P-L relations may not be independent of metallicity, as the P-L slopes and intercepts could be affected by the metallicity and/or helium abundance. We also derive the synthetic period-color (P-C) relations in the IRAC bands. Non-vanishing synthetic P-C relations were found for certain combinations of IRAC band filters and metallicity. However, the synthetic P-C relations disagreed with the [3.6]-[8.0] P-C relation recently found for the Galactic Cepheids. The synthetic [3.6]-[4.5] P-C slope from the (Y = 0.25, Z = 0.008) model set, on the other hand, is in excellent agreement to the empirical LMC P-C counterpart, if a period range 1.0 < log (P) < 1.8 is adopted.

Extreme MHC class I diversity in the sedge warbler (Acrocephalus schoenobaenus); selection patterns and allelic divergence suggest that different genes have different functions.

Science.gov (United States)

Biedrzycka, Aleksandra; O'Connor, Emily; Sebastian, Alvaro; Migalska, Magdalena; Radwan, Jacek; Zając, Tadeusz; Bielański, Wojciech; Solarz, Wojciech; Ćmiel, Adam; Westerdahl, Helena

2017-07-05

Recent work suggests that gene duplications may play an important role in the evolution of immunity genes. Passerine birds, and in particular Sylvioidea warblers, have highly duplicated major histocompatibility complex (MHC) genes, which are key in immunity, compared to other vertebrates. However, reasons for this high MHC gene copy number are yet unclear. High-throughput sequencing (HTS) allows MHC genotyping even in individuals with extremely duplicated genes. This HTS data can reveal evidence of selection, which may help to unravel the putative functions of different gene copies, i.e. neofunctionalization. We performed exhaustive genotyping of MHC class I in a Sylvioidea warbler, the sedge warbler, Acrocephalus schoenobaenus, using the Illumina MiSeq technique on individuals from a wild study population. The MHC diversity in 863 genotyped individuals by far exceeds that of any other bird species described to date. A single individual could carry up to 65 different alleles, a large proportion of which are expressed (transcribed). The MHC alleles were of three different lengths differing in evidence of selection, diversity and divergence within our study population. Alleles without any deletions and alleles containing a 6 bp deletion showed characteristics of classical MHC genes, with evidence of multiple sites subject to positive selection and high sequence divergence. In contrast, alleles containing a 3 bp deletion had no sites subject to positive selection and had low divergence. Our results suggest that sedge warbler MHC alleles that either have no deletion, or contain a 6 bp deletion, encode classical antigen presenting MHC molecules. In contrast, MHC alleles containing a 3 bp deletion may encode molecules with a different function. This study demonstrates that highly duplicated MHC genes can be characterised with HTS and that selection patterns can be useful for revealing neofunctionalization. Importantly, our results highlight the need to consider the

Violence in the prehistoric period of Japan: the spatio-temporal pattern of skeletal evidence for violence in the Jomon period.

Science.gov (United States)

Nakao, Hisashi; Tamura, Kohei; Arimatsu, Yui; Nakagawa, Tomomi; Matsumoto, Naoko; Matsugi, Takehiko

2016-03-01

Whether man is predisposed to lethal violence, ranging from homicide to warfare, and how that may have impacted human evolution, are among the most controversial topics of debate on human evolution. Although recent studies on the evolution of warfare have been based on various archaeological and ethnographic data, they have reported mixed results: it is unclear whether or not warfare among prehistoric hunter-gatherers was common enough to be a component of human nature and a selective pressure for the evolution of human behaviour. This paper reports the mortality attributable to violence, and the spatio-temporal pattern of violence thus shown among ancient hunter-gatherers using skeletal evidence in prehistoric Japan (the Jomon period: 13 000 cal BC-800 cal BC). Our results suggest that the mortality due to violence was low and spatio-temporally highly restricted in the Jomon period, which implies that violence including warfare in prehistoric Japan was not common. © 2016 The Author(s).

CRISPR Distribution within the Escherichia coli Species Is Not Suggestive of Immunity-Associated Diversifying Selection ▿ †

Science.gov (United States)

Touchon, Marie; Charpentier, Sophie; Clermont, Olivier; Rocha, Eduardo P. C.; Denamur, Erick; Branger, Catherine

2011-01-01

In order to get further insights into the role of the clustered, regularly interspaced, short palindromic repeats (CRISPRs) in Escherichia coli, we analyzed the CRISPR diversity in a collection of 290 strains, in the phylogenetic framework of the strains represented by multilocus sequence typing (MLST). The set included 263 natural E. coli isolates exposed to various environments and isolated over a 20-year period from humans and animals, as well as 27 fully sequenced strains. Our analyses confirm that there are two largely independent pairs of CRISPR loci (CRISPR1 and -2 and CRISPR3 and -4), each associated with a different type of cas genes (Ecoli and Ypest, respectively), but that each pair of CRISPRs has similar dynamics. Strikingly, the major phylogenetic group B2 is almost devoid of CRISPRs. The majority of genomes analyzed lack Ypest cas genes and contain CRISPR3 with spacers matching Ypest cas genes. The analysis of relatedness between strains in terms of spacer repertoire and the MLST tree shows a pattern where closely related strains (MLST phylogenetic distance of 0.01) exhibit completely different CRISPRs. This suggests rare but radical turnover of spacers in CRISPRs rather than CRISPR gradual change. We found no link between the presence, size, or content of CRISPRs and the lifestyle of the strains. Our data suggest that, within the E. coli species, CRISPRs do not have the expected characteristics of a classical immune system. PMID:21421763

On complex periodic motions and bifurcations in a periodically forced, damped, hardening Duffing oscillator

International Nuclear Information System (INIS)

Guo, Yu; Luo, Albert C.J.

2015-01-01

In this paper, analytically predicted are complex periodic motions in the periodically forced, damped, hardening Duffing oscillator through discrete implicit maps of the corresponding differential equations. Bifurcation trees of periodic motions to chaos in such a hardening Duffing oscillator are obtained. The stability and bifurcation analysis of periodic motion in the bifurcation trees is carried out by eigenvalue analysis. The solutions of all discrete nodes of periodic motions are computed by the mapping structures of discrete implicit mapping. The frequency-amplitude characteristics of periodic motions are computed that are based on the discrete Fourier series. Thus, the bifurcation trees of periodic motions are also presented through frequency-amplitude curves. Finally, based on the analytical predictions, the initial conditions of periodic motions are selected, and numerical simulations of periodic motions are carried out for comparison of numerical and analytical predictions. The harmonic amplitude spectrums are also given for the approximate analytical expressions of periodic motions, which can also be used for comparison with experimental measurement. This study will give a better understanding of complex periodic motions in the hardening Duffing oscillator.

Monitoring of scrap loads at Gorzia border checkpoints: A thirty months experience and some suggestions

International Nuclear Information System (INIS)

Fabretto, M.

1999-01-01

The following topics are highlighted: personnel training, assistance from foreign scrap suppliers, and computerized database. It is suggested that when selecting personnel for this job, major attention should be paid to their attitudes; the personnel should be given very good training, teaching them also how to make controls manually; expert physicist' support should be available within a very short time; each monitoring checkpoint should have its local electronic database; periodical exchange and updating of information should be practised on the standardization of methods of detection, of levels of attention and alarm, of statistics among the people in charge of EU and non-EU countries. (P.A.)

Selective appearance of several laser-induced periodic surface structure patterns on a metal surface using structural colors produced by femtosecond laser pulses

Energy Technology Data Exchange (ETDEWEB)

Yao Jianwu; Zhang Chengyun; Liu Haiying; Dai Qiaofeng; Wu Lijun [Laboratory of Photonic Information Technology, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006 (China); Lan, Sheng, E-mail: slan@scnu.edu.cn [Laboratory of Photonic Information Technology, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006 (China); Gopal, Achanta Venu [Department of Condensed Matter Physics and Material Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India); Trofimov, Vyacheslav A.; Lysak, Tatiana M. [Department of Computational Mathematics and Cybernetics, M. V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation)

2012-07-15

Ripples with a subwavelength period were induced on the surface of a stainless steel (301 L) foil by femtosecond laser pulses. By optimizing the irradiation fluence of the laser pulses and the scanning speed of the laser beam, ripples with large amplitude ({approx}150 nm) and uniform period could be obtained, rendering vivid structural colors when illuminating the surface with white light. It indicates that these ripples act as a surface grating that diffracts light efficiently. The strong dependence of the ripple orientation on the polarization of laser light offers us the opportunity of decorating different regions of the surface with different types of ripples. As a result, different patterns can be selectively displayed with structural color when white light is irradiated on the surface from different directions. More interestingly, we demonstrated the possibility of decorating the same region with two or more types of ripples with different orientations. In this way, different patterns with spatial overlapping can be selectively displayed with structural color. This technique may find applications in the fields of anti-counterfeiting, color display, decoration, encryption and optical data storage.

Selective vancomycin detection using optical fibre long period gratings functionalised with molecularly imprinted polymer nanoparticles.

Science.gov (United States)

Korposh, Sergiy; Chianella, Iva; Guerreiro, Antonio; Caygill, Sarah; Piletsky, Sergey; James, Stephen W; Tatam, Ralph P

2014-05-07

An optical fibre long period grating (LPG) sensor modified with molecularly imprinted polymer nanoparticles (nanoMIPs) for the specific detection of antibiotics is presented. The operation of the sensor is based on the measurement of changes in refractive index induced by the interaction of nanoMIPs deposited onto the cladding of the LPG with free vancomycin (VA). The binding of nanoMIPs to vancomycin was characterised by a binding constant of 4.3 ± 0.1 × 10(-8) M. The lowest concentration of analyte measured by the fibre sensor was 10 nM. In addition, the sensor exhibited selectivity, as much smaller responses were obtained for high concentrations (∼700 μM) of other commonly prescribed antibiotics such as amoxicillin, bleomycin and gentamicin. In addition, the response of the sensor was characterised in a complex matrix, porcine plasma, spiked with 10 μM of VA.

THEORETICAL CEPHEID PERIOD-LUMINOSITY AND PERIOD-COLOR RELATIONS IN SPITZER IRAC BANDS

Energy Technology Data Exchange (ETDEWEB)

Ngeow, Chow-Choong [Graduate Institute of Astronomy, National Central University, Jhongli City 32001, Taiwan (China); Marconi, Marcella; Musella, Ilaria [Osservatorio Astronomico di Capodimonte, Via Moiariello 16, 80131 Napoli (Italy); Cignoni, Michele [Department of Astronomy, Bologna University, via Ranzani 1, 40127 Bologna (Italy); Kanbur, Shashsi M. [Department of Physics, State University of New York at Oswego, Oswego, NY 13126 (United States)

2012-02-01

In this paper, the synthetic period-luminosity (P-L) relations in Spitzer's IRAC bands, based on a series of theoretical pulsation models with varying metal and helium abundance, were investigated. Selected sets of these synthetic P-L relations were compared to the empirical IRAC band P-L relations recently determined from Galactic and Magellanic Clouds Cepheids. For the Galactic case, synthetic P-L relations from model sets with (Y = 0.26, Z = 0.01), (Y = 0.26, Z = 0.02), and (Y = 0.28, Z = 0.02) agree with the empirical Galactic P-L relations derived from the Hubble Space Telescope parallaxes. For Magellanic Cloud Cepheids, the synthetic P-L relations from model sets with (Y = 0.25, Z = 0.008) agree with both of the empirical Large Magellanic Cloud (LMC) and Small Magellanic Cloud P-L relations. Analysis of the synthetic P-L relations from all model sets suggested that the IRAC band P-L relations may not be independent of metallicity, as the P-L slopes and intercepts could be affected by the metallicity and/or helium abundance. We also derive the synthetic period-color (P-C) relations in the IRAC bands. Non-vanishing synthetic P-C relations were found for certain combinations of IRAC band filters and metallicity. However, the synthetic P-C relations disagreed with the [3.6]-[8.0] P-C relation recently found for the Galactic Cepheids. The synthetic [3.6]-[4.5] P-C slope from the (Y = 0.25, Z = 0.008) model set, on the other hand, is in excellent agreement to the empirical LMC P-C counterpart, if a period range 1.0 < log (P) < 1.8 is adopted.

The role of tag suggestions in folksonomies

NARCIS (Netherlands)

Bollen, D.G.F.M.; Halpin, H.

2009-01-01

Most tagging systems support the user in the tag selection process by providing tag suggestions, or recommendations, based on a popularity measurement of tags other users provided when tagging the same resource. The majority of theories and mathematical models of tagging found in the literature

Space-based visual attention: a marker of immature selective attention in toddlers?

Science.gov (United States)

Rivière, James; Brisson, Julie

2014-11-01

Various studies suggested that attentional difficulties cause toddlers' failure in some spatial search tasks. However, attention is not a unitary construct and this study investigated two attentional mechanisms: location selection (space-based attention) and object selection (object-based attention). We investigated how toddlers' attention is distributed in the visual field during a manual search task for objects moving out of sight, namely the moving boxes task. Results show that 2.5-year-olds who failed this task allocated more attention to the location of the relevant object than to the object itself. These findings suggest that in some manual search tasks the primacy of space-based attention over object-based attention could be a marker of immature selective attention in toddlers. © 2014 Wiley Periodicals, Inc.

Sediment-palaeosol successions in Calabria and Sardinia suggest spatially differentiated palaeo-vegetation patterns in southern Italy during the Last Glacial period

Science.gov (United States)

Sauer, Daniela; Zucca, Claudio; Al-Sharif, Riyad; Zwanzig, Lisa; Madrau, Salvatore; Andreucci, Stefano; Pascucci, Vincenzo; Kadereit, Annette; Scarciglia, Fabio; Brückner, Helmut

2016-04-01

.9-30.3 ka cal BP, respectively. Thus, the formation of these soils falls into the period for which the lacustrine record indicates alternations between open and wooded steppe. The second palaeosol-sediment succession was found in a similar geomorphological situation near Piale, ca. 30 km north of the Lazzaro profile. In this case, the major part of the alluvial fan was removed by the creek (flowing from east to west), so that only its southernmost edge is preserved. SOM of the two lowermost palaeosols embedded in it was 14C-dated to 44.8-45.8 ka cal BP and 45.2-46.2 ka cal BP, respectively. The palaeosols of the Piale profile are very dark, almost carbonate-free, and several of them are characterized by an aeolian component (volcanic ash). The third sediment-palaeosol succession is exposed at the north-western coast of Sardinia, ca. 1.5 km north of Porto Palmas. The succession has developed in alluvial fan deposits that are constrained in a narrow valley, thus forming a valley infilling. Where the valley opens into the sea, this infilling is exposed in a high cliff. The sediment-palaeosol succession is sandwiched between marine deposits at the bottom (attributed to MIS 5c), and a sandy cover on top, dated to 23±4 ka by optically stimulated luminescence (OSL). 14C dating was performed on charcoal fragments that were abundant in several horizons. Interestingly, in contrast to the two sediment-palaeosol successions in Calabria, the palaeosols exposed in NW Sardinia do not represent dark steppe and forest steppe soils. The NW Sardinian Late Pleistocene palaeosols are brownish, reflecting rather forest environments. This difference suggests somewhat more humid and less continental conditions in this area compared to Calabria, during the Last Glacial period. However, more of these terrestrial archives along the coast of S Italy would need to be studied to gain a deeper understanding of spatial patterns of Last Glacial vegetation and environments.

Resonant Quasi-Optical Systems with Multi-Row Periodic Structures

DEFF Research Database (Denmark)

Oleksandr, Rybalko; Rybalko, Yu A.; Buriak, I. A.

2017-01-01

Selective properties of resonant quasi-optical systems with periodical multi-row structures in millimeter wavelength range are described. The possibility of selection fluctuations in the volume of open resonator using double-row periodic elements was shown in the experiment at 70-80 GHz. Advantages...... and possibility of control the energy characteristics of such structures are also described. The obtained experimental data is used to confirm the results of computational analysis previously described in the literature. Implementation of resonant quasi-optical systems with multi-row periodic structures...

Effect of periodic wetting and drying on selective sorption of 137Cs by mixtures of soil and organomineral sorbent

Science.gov (United States)

Popov, V. E.; Maslova, K. M.; Stepina, I. A.

2014-05-01

The incubation of sandy soddy-podzolic soil with a three-component organomineral sorbent (OMS) on the basis of sapropel, neutralized hydrolysis lignin, and clay-salt slime under alternating wetting-drying (W-D) conditions for two years has increased the selective sorption of 137Cs by 2.5-5 times. The addition of 5% OMS increases the effect of periodic W-D cycles on the selective sorption of 137Cs compared to the addition of 10% OMS. The relationship between the 137Cs interception potential and the number of W-D cycles has been predicted on the basis of the additivity rule and under the assumption that this potential linearly depends on the number of W-D cycles. The predicted values of the 137Cs interception potential almost coincide with the experimental data for the mixtures of sandy soddy-podzolic soil with 10% OMS and are lower than the experimental values by 60% for the mixtures of soil with 10% OMS.

Optimal ground motion intensity measure for long-period structures

International Nuclear Information System (INIS)

Guan, Minsheng; Du, Hongbiao; Zeng, Qingli; Cui, Jie; Jiang, Haibo

2015-01-01

This paper aims to select the most appropriate ground motion intensity measure (IM) that is used in selecting earthquake records for the dynamic time history analysis of long-period structures. For this purpose, six reinforced concrete frame-core wall structures, designed according to modern seismic codes, are studied through dynamic time history analyses with a set of twelve selected earthquake records. Twelve IMs and two types of seismic damage indices, namely, the maximum seismic response-based and energy-based parameters, are chosen as the examined indices. Selection criteria such as correlation, efficiency, and proficiency are considered in the selection process. The optimal IM is identified by means of a comprehensive evaluation using a large number of data of correlation, efficiency, and proficiency coefficients. Numerical results illustrate that peak ground velocity is the optimal one for long-period structures and peak ground displacement is also a close contender. As compared to previous reports, the spectral-correlated parameters can only be taken as moderate IMs. Moreover, the widely used peak ground acceleration in the current seismic codes is considered inappropriate for long-period structures. (paper)

Biomimetic Wind Turbine Design with Lift Enhancing Periodic Stall

NARCIS (Netherlands)

Stamhuis, Eize Jan

2017-01-01

A wind turbine includes a rotor; a blade; and a periodic stall system. The periodic stall system selectively moves at least part of the blade in an oscillating motion whereby an angle of incidence continuously varies to invoke periodic stall. The periodic stall system can move the entire blade or

The Transition Period in Soccer: A Window of Opportunity.

Science.gov (United States)

Silva, Joao Renato; Brito, Joao; Akenhead, Richard; Nassis, George P

2016-03-01

The aim of this paper is to describe the physiological changes that occur during the transition period in soccer players. A secondary aim is to address the issue of utilizing the transition period to lay the foundation for the succeeding season. We reviewed published peer-reviewed studies if they met the following three selection criteria: (1) the studied population comprised adult soccer players (aged >18 years), (2) time points of physiological and performance assessments were provided, and (3) appropriate statistics for the calculation of effect sizes were reported. Following two selection phases, 12 scientific publications were considered, involving a total sample of 252 players. The transition period elicits small to moderate negative changes in body composition, a moderate decline in sprint performance with and without changes of direction, and small to moderate decrements in muscle power. Detraining effects are also evident for endurance-related physiological and performance outcomes: large decrements in maximal oxygen consumption V̇O2max) and time to exhaustion, and moderate to very large impairments have been observed in intermittent-running performance. Off-season programs should be characterized by clear training objectives, a low frequency of training sessions, and simple training tools in order to facilitate compliance. The program suggested here may constitute the 'minimum effective dose' to maintain or at least attenuate the decay of endurance- and neuromuscular-related performance parameters, as well as restore an adequate strength profile (reduce muscle strength imbalances). This periodization strategy may improve the ability of players to cope with the elevated training demands of pre-season training and therefore reduce the risk of injury. Moreover, this strategy will favor a more efficient development of other relevant facets of performance during the pre-competition phase (e.g., tactical organization). We contend that the transition period

PERIODIC VARIABILITY OF LOW-MASS STARS IN SLOAN DIGITAL SKY SURVEY STRIPE 82

International Nuclear Information System (INIS)

Becker, A. C.; Hawley, S. L.; Ivezic, Z.; Kowalski, A. F.; Sesar, B.; Bochanski, J. J.; West, A. A.

2011-01-01

We present a catalog of periodic stellar variability in the 'Stripe 82' region of the Sloan Digital Sky Survey. After aggregating and re-calibrating catalog-level data from the survey, we ran a period-finding algorithm (Supersmoother) on all point-source light curves. We used color selection to identify systems that are likely to contain low-mass stars, in particular M dwarfs and white dwarfs. In total, we found 207 candidates, the vast majority of which appear to be in eclipsing binary systems. The catalog described in this paper includes 42 candidate M dwarf/white dwarf pairs, four white dwarf pairs, 59 systems whose colors indicate they are composed of two M dwarfs and whose light-curve shapes suggest they are in detached eclipsing binaries, and 28 M dwarf systems whose light-curve shapes suggest they are in contact binaries. We find no detached systems with periods longer than 3 days, thus the majority of our sources are likely to have experienced orbital spin-up and enhanced magnetic activity. Indeed, 26 of 27 M dwarf systems that we have spectra for show signs of chromospheric magnetic activity, far higher than the 24% seen in field stars of the same spectral type. We also find binaries composed of stars that bracket the expected boundary between partially and fully convective interiors, which will allow the measurement of the stellar mass-radius relationship across this transition. The majority of our contact systems have short orbital periods, with small variance (0.02 days) in the sample near the observed cutoff of 0.22 days. The accumulation of these stars at short orbital period suggests that the process of angular momentum loss, leading to period evolution, becomes less efficient at short periods. These short-period systems are in a novel regime for studying the effects of orbital spin-up and enhanced magnetic activity, which are thought to be the source of discrepancies between mass-radius predictions and measurements of these properties in eclipsing

Thyroid Cancer Incidences From Selected South America Population-Based Cancer Registries: An Age-Period-Cohort Study

Directory of Open Access Journals (Sweden)

Anne Karin da Mota Borges

2017-08-01

Full Text Available Purpose: The incidence of thyroid cancer (TC has increased substantially worldwide. However, there is a lack of knowledge about age-period-cohort (APC effects on incidence rates in South American countries. This study describes the TC incidence trends and analyzes APC effects in Cali, Colombia; Costa Rica; Goiânia, Brazil; and Quito, Ecuador. Materials and Methods: Data were obtained from the Cancer Incidence in Five Continents series, and the crude and age-standardized incidence rates were calculated. Trends were assessed using the estimated annual percentage change, and APC models were estimated using Poisson regression for individuals between age 20 and 79 years. Results: An increasing trend in age-standardized incidence rates was observed among women from Goiânia (9.2%, Costa Rica (5.7%, Quito (4.0%, and Cali (3.4%, and in men from Goiânia (10.0% and Costa Rica (3.4%. The APC modeling showed that there was a period effect in all regions and for both sexes. Increasing rate ratios were observed among women over the periods. The best fit model was the APC model in women from all regions and in men from Quito, whereas the age-cohort model showed a better fit in men from Cali and Costa Rica, and the age-drift model showed a better fit among men from Goiânia. Conclusion: These findings suggest that overdiagnosis is a possible explanation for the observed increasing pattern of TC incidence. However, some environmental exposures may also have contributed to the observed increase.

Feed resource selection of Criollo goats artificially infected with Haemonchus contortus: nutritional wisdom and prophylactic self-medication.

Science.gov (United States)

Ventura-Cordero, J; González-Pech, P G; Jaimez-Rodriguez, P R; Ortiz-Ocampo, G I; Sandoval-Castro, C A; Torres-Acosta, J F J

2018-06-01

Previous cafeteria studies suggested that a moderate natural gastrointestinal nematode (GIN) infection did not modify the resource selection of adult Criollo goats towards tannin-rich plants compared with worm-free goats. A higher infection with Haemonchus contortus could trigger a change in the resource selection behaviour towards tannin-rich foliage. Alternatively, goats might select plant species solely to meet their nutritional requirements. A cafeteria study investigated the effect of a high artificial infection with H. contortus on the feed resource selection of goats. Adult Criollo goats (37.5±4.8 kg BW) with browsing experience were distributed in two groups: the infected group (IG) with six animals artificially infected with H. contortus (6000 L3/animal); and the non-infected group (NIG) with six animals maintained worm-free. The experiment included two 5-day periods with additional 5-day adaptation period. In the first period, animals were offered foliage of five plant species with a decreasing gradient of condensed tannins (CT) (Mimosa bahamensis, Gymnopodium floribundum, Havardia albicans, Acacia pennatula, Lysiloma latisiliqum), and three plant species with negligible CT content (Leucaena leucocephala, Piscidia piscipula and Brosimum alicastrum). In the second period the foliage of B. alicastrum was withdrawn. A grain-based concentrate feed was offered daily at 1% BW in DM basis. Dry matter and nutrient intake was determined. Foliage selection of each experimental group was determined using the Chesson selection index. The H. contortus egg count per gram of faeces (EPG) was determined for infected goats twice daily. Chesson index showed a similar pattern of foliage selection on periods 1 and 2. Mean EPG of goats in IG was 2028±259 EPG during period 1 and 1 293±198 EPG during period 2 (P>0.05). During period 1, the selection pattern was highest for B. alicastrum (tannin-free), followed by a tannin-rich plant (M. bahamensis). These two plants remained

Periodic Properties and Inquiry: Student Mental Models Observed during a Periodic Table Puzzle Activity

Science.gov (United States)

Larson, Kathleen G.; Long, George R.; Briggs, Michael W.

2012-01-01

The mental models of both novice and advanced chemistry students were observed while the students performed a periodic table activity. The mental model framework seems to be an effective way of analyzing student behavior during learning activities. The analysis suggests that students do not recognize periodic trends through the examination of…

Obsessive-compulsive disorder in the perinatal period: epidemiology, phenomenology, pathogenesis, and treatment

Directory of Open Access Journals (Sweden)

Álvaro Frías

2015-01-01

Full Text Available The aim of this review is to describe the main theoretical findings and research conclusions about obsessive-compulsive disorder (OCD in the perinatal period. On one hand, epidemiological studies show that the risk of OCD onset and/or exacerbation could increase in this period, particularly in the puerperium. Phenomenologically, in this stage aggressive and contamination obsessions are very common and are related to the fetus or newborn. On the other hand, regarding OCD pathogenesis in this period, there is indirect evidence to suggest the participation of neuroendocrine (e.g. female gonadal steroids and oxytocin and cognitive behavioural variables (e.g. hyper-responsibility, threat overestimation, and mental control. In terms of research, more empirical studies are needed to contrast these specific vulnerability factors. Moreover, no empirically validated psychotherapeutic treatments (controlled trials adapted to this OCD sub-group were found, although some studies highlight the role of cognitive behavioural therapy (CBT as an effective intervention in the context of selective primary prevention.

Phylogenetic analysis suggests that sociality is associated with reduced effectiveness of selection

DEFF Research Database (Denmark)

Settepani, Virginia; Bechsgaard, Jesper Smærup; Bilde, Trine

2016-01-01

significantly between the social inbreeding and outcrossing species, but suggest a tendency for lower codon usage bias and higher dN/dS ratios in the social inbreeding species compared with their outcrossing congeners. The differences in dN/dS ratio and codon usage bias between social and subsocial species...

Task-irrelevant distractors in the delay period interfere selectively with visual short-term memory for spatial locations.

Science.gov (United States)

Marini, Francesco; Scott, Jerry; Aron, Adam R; Ester, Edward F

2017-07-01

Visual short-term memory (VSTM) enables the representation of information in a readily accessible state. VSTM is typically conceptualized as a form of "active" storage that is resistant to interference or disruption, yet several recent studies have shown that under some circumstances task-irrelevant distractors may indeed disrupt performance. Here, we investigated how task-irrelevant visual distractors affected VSTM by asking whether distractors induce a general loss of remembered information or selectively interfere with memory representations. In a VSTM task, participants recalled the spatial location of a target visual stimulus after a delay in which distractors were presented on 75% of trials. Notably, the distractor's eccentricity always matched the eccentricity of the target, while in the critical conditions the distractor's angular position was shifted either clockwise or counterclockwise relative to the target. We then computed estimates of recall error for both eccentricity and polar angle. A general interference model would predict an effect of distractors on both polar angle and eccentricity errors, while a selective interference model would predict effects of distractors on angle but not on eccentricity errors. Results showed that for stimulus angle there was an increase in the magnitude and variability of recall errors. However, distractors had no effect on estimates of stimulus eccentricity. Our results suggest that distractors selectively interfere with VSTM for spatial locations.

Effects of a Period of Selected Activity on Lung Capacities in Children 5-10 Years with Asthma Caused by Exercise

Directory of Open Access Journals (Sweden)

Gholamreza Sharifi

2014-09-01

Full Text Available Background: Aasthma due to causing disruption in the work of breathing and obstruction of the pulmonary tract creates the physical restrictions in the social, emotional and psychological, aspects and performing daily life activities, hence the present study is conducted to determine the impact of a period of selected activity on some spirometry parameters of children from 5 to 10 years old suffering from asthma caused by exercise.Materials and Methods: In this half experimental respiratory research, respiratory indexes of 11 children including 5 boys under the age of 10 years old suffering from asthma caused by exercise were measured before and after eight weeks of selected exercises and pranayama by spirometry were measured.Results: The results showed that the selected exercise routine improves on the status of activities and being short of breath (Z=0/003. Also the average of spirometry indexes prior to a ten minutes exercise, before and after the intervention, compared with the average of spirometry indexes after a ten minute exercise, before and after intervention in the parameters: (fev1 the volume of the expiratory force in the first second, and (PEF the maximum expiratory flow, the results are statistically significant (p 0.05.Conclusions: The present study shows the impact of the selected exercises in improving mobility status and being short of breath and reducing asthma symptoms caused by exercise (EIA as well as strengthening the respiratory muscles significantly.

Utilization of critical periods during development to study the effects of low levels of environmental agents

International Nuclear Information System (INIS)

Russell, L.B.

1981-01-01

This chapter shows how careful definition of critical periods in the development of selected characters can result in experimental systems that may be highly useful in studying risk at low levels of exposure. Presents 3 systems that utilize critical periods to study low-level effects: 1) cell kinetics as an indicator of nervous-system maldevelopment; 2) oocyte depletion; and 3) homeotic shifts in the skeleton. Discusses application of the sensitive systems to the testing of chemicals and the role of sensitive stages in estimating risk. Suggests that tests such as the 3 discussed in this paper, which are developed with strict attention to specific critical periods, can provide rapid and sensitive means for revealing whether an agent is capable of causing developmental interference. Concludes that epidemiological investigations can lose much of their value unless critical periods are known for the endpoints being studied

Diel habitat selection of largemouth bass following woody structure installation in Table Rock Lake, Missouri

Science.gov (United States)

Harris, J.M.; Paukert, Craig P.; Bush, S.C.; Allen, M.J.; Siepker, Michael

2018-01-01

Largemouth bass Micropterus salmoides (Lacepède) use of installed habitat structure was evaluated in a large Midwestern USA reservoir to determine whether or not these structures were used in similar proportion to natural habitats. Seventy largemouth bass (>380 mm total length) were surgically implanted with radio transmitters and a subset was relocated monthly during day and night for one year. The top habitat selection models (based on Akaike's information criterion) suggest largemouth bass select 2–4 m depths during night and 4–7 m during day, whereas littoral structure selection was similar across diel periods. Largemouth bass selected boat docks at twice the rate of other structures. Installed woody structure was selected at similar rates to naturally occurring complex woody structure, whereas both were selected at a higher rate than simple woody structure. The results suggest the addition of woody structure may concentrate largemouth bass and mitigate the loss of woody habitat in a large reservoir.

How are flood risk estimates affected by the choice of return-periods?

Science.gov (United States)

Ward, P. J.; de Moel, H.; Aerts, J. C. J. H.

2011-12-01

Flood management is more and more adopting a risk based approach, whereby flood risk is the product of the probability and consequences of flooding. One of the most common approaches in flood risk assessment is to estimate the damage that would occur for floods of several exceedance probabilities (or return periods), to plot these on an exceedance probability-loss curve (risk curve) and to estimate risk as the area under the curve. However, there is little insight into how the selection of the return-periods (which ones and how many) used to calculate risk actually affects the final risk calculation. To gain such insights, we developed and validated an inundation model capable of rapidly simulating inundation extent and depth, and dynamically coupled this to an existing damage model. The method was applied to a section of the River Meuse in the southeast of the Netherlands. Firstly, we estimated risk based on a risk curve using yearly return periods from 2 to 10 000 yr (€ 34 million p.a.). We found that the overall risk is greatly affected by the number of return periods used to construct the risk curve, with over-estimations of annual risk between 33% and 100% when only three return periods are used. In addition, binary assumptions on dike failure can have a large effect (a factor two difference) on risk estimates. Also, the minimum and maximum return period considered in the curve affects the risk estimate considerably. The results suggest that more research is needed to develop relatively simple inundation models that can be used to produce large numbers of inundation maps, complementary to more complex 2-D-3-D hydrodynamic models. It also suggests that research into flood risk could benefit by paying more attention to the damage caused by relatively high probability floods.

Midterm Periodicity Analysis of the Mount Wilson Magnetic Indices Using the Synchrosqueezing Transform

Energy Technology Data Exchange (ETDEWEB)

Feng, Song; Wang, Feng; Deng, Hui; Yang, Yunfei [Yunnan Key Laboratory of Computer Technology Application/Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500 (China); Yu, Lan, E-mail: ynkmfs@escience.cn [Department of Mechanical and Electrical Engineering, Yunnan Land and Resources Vocational College, Kunming 650217 (China)

2017-08-10

A novel time–frequency technique, called the synchrosqueezing transform (SST), is used to investigate the midterm periodic variations of magnetic fields on the solar surface. The Magnetic Plage Strength Index (MPSI) and the Mount Wilson Sunspot Index (MWSI), measured daily by the Mount Wilson Observatory between 1970 January 19 and 2012 January 22, are selected. Short-, mid, and longer-term periodicities are represented and decomposed by the SST with hardly any mode mixing. This demonstrates that the SST is a useful time–frequency analysis technique to characterize the periodic modes of helioseismic data. Apart from the fundamental modes of the annual periodicity, ∼27 day rotational cycle and ∼11 year solar cycle, the SST reveals several midterm periodicities in the two magnetic activity indices, specifically, ∼157 days (i.e., Rieger-type periodicity), and ∼1.3 and 1.7 years. The periodic modes, with 116.4 and 276.2 day periodicity in the MPSI, 108.5 and 251.6 day periodicity in the MWSI, and 157.7 day periodicity in the two indices, are in better accord with those significant periodicities derived from the Rossby waves theoretical model. This study suggests that the modes are caused by Rossby waves. For the 1.30 and 1.71 year periodicity of the MPSI, and the 1.33 and 1.67 year periodicity of the MWSI, our analysis infers that they are related to those periodicities with the same timescale in the interior of the Sun and in the high atmospheric layers.

Temp-to-permanent employees: a longitudinal study of stress and selection success.

Science.gov (United States)

Bauer, T N; Truxillo, D M

2000-07-01

Temp-to-permanent employees are temporary workers who have the opportunity to become permanent employees after a specific amount of time (e.g., generally after a 3- to 12-month period of trial work). The authors predicted that temporary worker individual differences, self-monitoring, tolerance for ambiguity, and role adjustment are related to temporary worker physiological stress and to whether temporary employees are offered permanent employment. Longitudinal data collection (pre- and postentry) resulted in data from 136 temp-to-permanent employees. Tolerance for ambiguity and role adjustment were found to be related to temporary worker stress and selection success. Self-monitoring was related to selection success for workers in an extended probationary period. These results suggest the need for further exploration and application of models of stress in understanding factors related to temporary worker success.

Quasi-periodic photonic crystal Fabry–Perot optical filter based on Si/SiO2 for visible-laser spectral selectivity

Science.gov (United States)

Qi, Dong; Wang, Xian; Cheng, Yongzhi; Chen, Fu; Liu, Lei; Gong, Rongzhou

2018-06-01

We report on a 1D quasi-periodic photonic crystal Fabry–Perot optical filter Cs(Si/SiO2)3(SiO2/Si)3 for spectral selectivity of visible light and 1.55 µm laser. A material transparency interval of 1.03–2.06 µm makes Si a unique choice of high refractive index material. Owing to the CIE 1931 standard and equal inclination interference, the designed structure can be successfully fabricated with a certain color (brown, khaki, or blue) corresponding to the different Cs physical thickness d and response R(λ). In addition, the peak transmittance T max of the proposed structure can reach as high as 92.56% (Cs  =  20 nm), 90.83% (Cs  =  40 nm), and 88.85% (Cs  =  60 nm) with a relatively narrow full width at half maximum of 4.4, 4.6, and 4.8 nm at 1.55 µm. The as-prepared structure indicates that it is feasible for a photonic crystal Fabry–Perot optical filter to achieve visible-laser (1.55 µm) spectral selectivity.

Napping and the Selective Consolidation of Negative Aspects of Scenes

Science.gov (United States)

Payne, Jessica D.; Kensinger, Elizabeth A.; Wamsley, Erin; Spreng, R. Nathan; Alger, Sara; Gibler, Kyle; Schacter, Daniel L.; Stickgold, Robert

2018-01-01

After information is encoded into memory, it undergoes an offline period of consolidation that occurs optimally during sleep. The consolidation process not only solidifies memories, but also selectively preserves aspects of experience that are emotionally salient and relevant for future use. Here, we provide evidence that an afternoon nap is sufficient to trigger preferential memory for emotional information contained in complex scenes. Selective memory for negative emotional information was enhanced after a nap compared to wakefulness in two control conditions designed to carefully address interference and time-of-day confounds. Although prior evidence has connected negative emotional memory formation to rapid eye movement (REM) sleep physiology, we found that non-REM delta activity and the amount of slow wave sleep (SWS) in the nap were robustly related to the selective consolidation of negative information. These findings suggest that the mechanisms underlying memory consolidation benefits associated with napping and nighttime sleep are not always the same. Finally, we provide preliminary evidence that the magnitude of the emotional memory benefit conferred by sleep is equivalent following a nap and a full night of sleep, suggesting that selective emotional remembering can be economically achieved by taking a nap. PMID:25706830

Suggestibility and suggestive modulation of the Stroop effect.

Science.gov (United States)

Kirsch, Irving

2011-06-01

Although the induction of a hypnotic state does not seem necessary for suggestive modulation of the Stroop effect, this important phenomenon has seemed to be dependent on the subject's level of hypnotic suggestibility. Raz and Campbell's (2011) study indicates that suggestion can modulate the Stroop effect substantially in very low suggestible subjects, as well as in those who are highly suggestible. This finding casts doubt on the presumed mechanism by which suggestive modulation is brought about. Research aimed at uncovering the means by which low suggestible individuals are able to modulate the Stroop effect would be welcome, as would assessment of this effect in moderately suggestible people. Copyright © 2010 Elsevier Inc. All rights reserved.

A powerful test for weak periodic signals with unknown light curve shape in sparse data

International Nuclear Information System (INIS)

Jager De, O.C.; Raubenheimer, B.C.; Swanepoel, J.W.H.

1989-01-01

A problem with most tests for periodicity is that they are powerful enough to detect only certain kinds of periodic shapes in the case of weak signals. This causes a selection effect with the identification of weak periodic signals. A new test for uniformity called the H-test is derived for which the probability distribution is an exponential function. This test is shown to have a very good power against most light curve shapes encountered in X- and γ-ray Astronomy and therefore makes the detection of sources with a larger variety of shapes possible. The use of the H-test is suggested if no a priori information about the light curve shape is available. It is also shown how the probability distribution of the test statistics changes when a periodicity search is conducted using very small steps in the period or frequency range. The flux sensitivity for various light curve shapes is also derived for a few tests and this flux is on average a minimum for the H-test

Archeointensities in Greece during the Neolithic period: New insights into material selection and secular variation curve

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Fanjat, G.; Aidona, E.; Kondopoulou, D.; Camps, P.; Rathossi, C.; Poidras, T.

2013-02-01

Numerous archeomagnetic studies have provided high quality data for both the direction and the intensity of the geomagnetic field, essentially in Europe for the last 10 millennia. In particular, Greece supplies a lot of archeological materials due to its impressive cultural heritage and volcanic activity, so that numerous data have been obtained from burnt clays or historical lava flows. The most recent Greek secular variation curves are available for the last 8 millennia for the intensity and the last 6 millennia for the direction. Nevertheless, the coverage still presents several gaps for periods older than 2500 BC. In an effort to complete the Greek curve and extend it to older times, we present the archeointensity results from three Neolithic settlements in Northern Greece. The samples are of two different natures: burnt structures from Avgi (5250 ± 150 BC) and Vasili (4800 ± 200 BC), as well as ceramics from Dikili Tash (4830 ± 80 BC) and Vasili (4750 ± 250 BC). The samples have been subjected to standard rock magnetic analyses in order to estimate the thermal stability and the domain state of the magnetic carriers before archeointensity measurements. Surprisingly, very few ceramic samples provided reliable archeointensities whereas samples from burnt structures presented a very good success rate. Complementary studies showed that a detailed examination of the matrix color, following archeological information and classification standards can be a decisive test for pre-selection of sherds. In spite of these unsuccessful measurements from ceramics, we obtained an intensity value of 73.5 ± 1.1 μT for Dikili Tash, a higher value than the other data obtained in the same area, during the same period. However we do not have evidences for a technical artefact during the experiment. The burnt structures yielded two reliable archeointensities of 36.1 ± 1.8 μT and 46.6 ± 3.4 μT for Avgi and Vasili, respectively. Finally, we achieved a new archeomagnetic dating

A spatio-temporal synchronization of periodic markets: evidence ...

African Journals Online (AJOL)

This study seeks to identify the 'rings' of periodic market days in Akwa Ibom State, using eighteen periodic markets as case study The entire landmass of the state was covered with a network of grids. These grids were numbered and a table of random numbers was used in selecting a target population of eighteen ...

Evaluation of selected physicochemical parameters of extra virgin olive oil commercialized in the Czech market and stored during a period of 5 months

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Richardos Nikolaos Salek

2017-01-01

Full Text Available The scope of this work was to evaluate the development of selected physicochemical parameters (free acidity, peroxide value and specific extinction coefficients in ultraviolet of extra virgin olive oil, commercialized in the Czech market and stored for a time period of 5 months (at 20 ±5 °C. The tested extra virgin olive oil samples were stored under conditions simulating domestic and commercial storage environment, in which the impact of light and headspace volume were also examined. Moreover, all the analyzed samples fell within the established "extra virgin olive oil category", thus proving their legitimacy, authentication and excellent quality. Furthermore, all the monitored physicochemical parameters were affected by the progress of the storage period, the rising volume of headspace (due to more available oxygen in the container and exposition to light, resulting in decreasing quality of the examined extra virgin olive oil samples. In addition, the storage of extra virgin olive oil samples in dark containers reported sufficient resistance to oxidation processes up to a period of 3 months, however, after this period signs of oil quality deterioration were reported. Nevertheless, if exposition to light occurred, accelerated decrease in the quality of the extra virgin olive oil samples was observed.

Ferritin gene organization: differences between plants and animals suggest possible kingdom-specific selective constraints.

Science.gov (United States)

Proudhon, D; Wei, J; Briat, J; Theil, E C

1996-03-01

Ferritin, a protein widespread in nature, concentrates iron approximately 10(11)-10(12)-fold above the solubility within a spherical shell of 24 subunits; it derives in plants and animals from a common ancestor (based on sequence) but displays a cytoplasmic location in animals compared to the plastid in contemporary plants. Ferritin gene regulation in plants and animals is altered by development, hormones, and excess iron; iron signals target DNA in plants but mRNA in animals. Evolution has thus conserved the two end points of ferritin gene expression, the physiological signals and the protein structure, while allowing some divergence of the genetic mechanisms. Comparison of ferritin gene organization in plants and animals, made possible by the cloning of a dicot (soybean) ferritin gene presented here and the recent cloning of two monocot (maize) ferritin genes, shows evolutionary divergence in ferritin gene organization between plants and animals but conservation among plants or among animals; divergence in the genetic mechanism for iron regulation is reflected by the absence in all three plant genes of the IRE, a highly conserved, noncoding sequence in vertebrate animal ferritin mRNA. In plant ferritin genes, the number of introns (n = 7) is higher than in animals (n = 3). Second, no intron positions are conserved when ferritin genes of plants and animals are compared, although all ferritin gene introns are in the coding region; within kingdoms, the intron positions in ferritin genes are conserved. Finally, secondary protein structure has no apparent relationship to intron/exon boundaries in plant ferritin genes, whereas in animal ferritin genes the correspondence is high. The structural differences in introns/exons among phylogenetically related ferritin coding sequences and the high conservation of the gene structure within plant or animal kingdoms of the gene structure within plant or animal kingdoms suggest that kingdom-specific functional constraints may

Deep-sea octopus (Graneledone boreopacifica) conducts the longest-known egg-brooding period of any animal.

Science.gov (United States)

Robison, Bruce; Seibel, Brad; Drazen, Jeffrey

2014-01-01

Octopuses typically have a single reproductive period and then they die (semelparity). Once a clutch of fertilized eggs has been produced, the female protects and tends them until they hatch. In most shallow-water species this period of parental care can last from 1 to 3 months, but very little is known about the brooding of deep-living species. In the cold, dark waters of the deep ocean, metabolic processes are often slower than their counterparts at shallower depths. Extrapolations from data on shallow-water octopus species suggest that lower temperatures would prolong embryonic development periods. Likewise, laboratory studies have linked lower temperatures to longer brooding periods in cephalopods, but direct evidence has not been available. We found an opportunity to directly measure the brooding period of the deep-sea octopus Graneledone boreopacifica, in its natural habitat. At 53 months, it is by far the longest egg-brooding period ever reported for any animal species. These surprising results emphasize the selective value of prolonged embryonic development in order to produce competitive hatchlings. They also extend the known boundaries of physiological adaptations for life in the deep sea.

Suggestions for the Classical Shelves of a School Library.

Science.gov (United States)

Colebourn, R., Comp.; Cleeve, Marigold, Comp.

This bibliography is suggested for use by students and teachers of Latin, Greek and ancient civilizations. Entries are compiled under the headings of: (1) bibliographies and journals including booklists, periodicals, and books for teachers; (2) reference works in literature, mythology, history and antiquities, and language; (3) texts and…

Optical Frequency Mixing in Periodically-Patterned and in Quasi-Periodically-Patterned Nonlinear media

International Nuclear Information System (INIS)

Arie, A.

1999-01-01

Nonlinear frequency mixing processes, e.g. second harmonic generation, sum and difference frequency generation, etc., require matching of the phases of the interacting waves. The traditional method to achieve it is by selecting a specific angle of propagation in a birefringent nonlinear crystal. The main limitation of the birefringent phase matching method stems from the fact that for many interesting interactions, the phase matching condition cannot be satisfied in a specific crystal. This obstacle can be removed by the technique of quasi-phase-matching (QPM), where the nonlinear coefficient of the material is modulated at a fixed spatial frequency that equals the wave-vector phase mismatch between the interacting waves. An important development in recent years is the ability to periodically reverse the sign of the nonlinear coefficient in ferroelectric crystals by applying a high electric field through a periodic electrode. Some recent QPM interactions in periodically-poled KTP that were recently achieved at Tel-Aviv University include continuous-wave optical parametric oscillations, as well as generation of tunable mid-infrared radiation by difference frequency generation. Periodic patterning of the nonlinear coefficient enables to phase match only a single interaction. It would be advantageous to further extend the applications of this technique in order to simultaneously satisfy several interactions on a single crystal. This cannot be usually achieved in a periodic pattern, however more sophisticated quasi-periodic structures can be designed in this case. An interesting analogy can be drawn between artificially-made quasi-periodically-patterned nonlinear crystals and quasi-crystals found in nature, in rapidly-cooled metallic alloys

A class of multi-period semi-variance portfolio for petroleum exploration and development

Science.gov (United States)

Guo, Qiulin; Li, Jianzhong; Zou, Caineng; Guo, Yujuan; Yan, Wei

2012-10-01

Variance is substituted by semi-variance in Markowitz's portfolio selection model. For dynamic valuation on exploration and development projects, one period portfolio selection is extended to multi-period. In this article, a class of multi-period semi-variance exploration and development portfolio model is formulated originally. Besides, a hybrid genetic algorithm, which makes use of the position displacement strategy of the particle swarm optimiser as a mutation operation, is applied to solve the multi-period semi-variance model. For this class of portfolio model, numerical results show that the mode is effective and feasible.

Incubation period and immune function: A comparative field study among coexisting birds

Science.gov (United States)

Palacios, M.G.; Martin, T.E.

2006-01-01

Developmental periods are integral components of life history strategies that can have important fitness consequences and vary enormously among organisms. However, the selection pressures and mechanisms causing variation in length of developmental periods are poorly understood. Particularly puzzling are prolonged developmental periods, because their selective advantage is unclear. Here we tested the hypotheses that immune function is stronger in species that are attacked at a higher rate by parasites and that prolonged embryonic development allows the development of this stronger immune system. Through a comparative field study among 12 coexisting passerine bird species, we show that species with higher blood parasite prevalence mounted stronger cellular immune responses than species with lower prevalence. These results provide support for the hypothesis that species facing greater selection pressure from parasites invest more in immune function. However, species with longer incubation periods mounted weaker cellular immune responses than species with shorter periods. Therefore, cellular immune responses do not support the hypothesis that longer development time enhances immunocompentence. Future studies should assess other components of the immune system and test alternative causes of variation in incubation periods among bird species. ?? Springer-Verlag 2005.

Decoding facial expressions based on face-selective and motion-sensitive areas.

Science.gov (United States)

Liang, Yin; Liu, Baolin; Xu, Junhai; Zhang, Gaoyan; Li, Xianglin; Wang, Peiyuan; Wang, Bin

2017-06-01

Humans can easily recognize others' facial expressions. Among the brain substrates that enable this ability, considerable attention has been paid to face-selective areas; in contrast, whether motion-sensitive areas, which clearly exhibit sensitivity to facial movements, are involved in facial expression recognition remained unclear. The present functional magnetic resonance imaging (fMRI) study used multi-voxel pattern analysis (MVPA) to explore facial expression decoding in both face-selective and motion-sensitive areas. In a block design experiment, participants viewed facial expressions of six basic emotions (anger, disgust, fear, joy, sadness, and surprise) in images, videos, and eyes-obscured videos. Due to the use of multiple stimulus types, the impacts of facial motion and eye-related information on facial expression decoding were also examined. It was found that motion-sensitive areas showed significant responses to emotional expressions and that dynamic expressions could be successfully decoded in both face-selective and motion-sensitive areas. Compared with static stimuli, dynamic expressions elicited consistently higher neural responses and decoding performance in all regions. A significant decrease in both activation and decoding accuracy due to the absence of eye-related information was also observed. Overall, the findings showed that emotional expressions are represented in motion-sensitive areas in addition to conventional face-selective areas, suggesting that motion-sensitive regions may also effectively contribute to facial expression recognition. The results also suggested that facial motion and eye-related information played important roles by carrying considerable expression information that could facilitate facial expression recognition. Hum Brain Mapp 38:3113-3125, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A suggested periodic table up to Z≤ 172, based on Dirac-Fock calculations on atoms and ions.

Science.gov (United States)

Pyykkö, Pekka

2011-01-07

Extended Average Level (EAL) Dirac-Fock calculations on atoms and ions agree with earlier work in that a rough shell-filling order for the elements 119-172 is 8s Periodic Table develops further that of Fricke, Greiner and Waber [Theor. Chim. Acta 1971, 21, 235] by formally assigning the elements 121-164 to (nlj) slots on the basis of the electron configurations of their ions. Simple estimates are made for likely maximum oxidation states, i, of these elements M in their MX(i) compounds, such as i = 6 for UF(6). Particularly high i are predicted for the 6f elements.

Sexual selection affects local extinction and turnover in bird communities

Science.gov (United States)

Doherty, P.F.; Sorci, G.; Royle, J. Andrew; Hines, J.E.; Nichols, J.D.; Boulinier, T.

2003-01-01

Predicting extinction risks has become a central goal for conservation and evolutionary biologists interested in population and community dynamics. Several factors have been put forward to explain risks of extinction, including ecological and life history characteristics of individuals. For instance, factors that affect the balance between natality and mortality can have profound effects on population persistence. Sexual selection has been identified as one such factor. Populations under strong sexual selection experience a number of costs ranging from increased predation and parasitism to enhanced sensitivity to environmental and demographic stochasticity. These findings have led to the prediction that local extinction rates should be higher for species/populations with intense sexual selection. We tested this prediction by analyzing the dynamics of natural bird communities at a continental scale over a period of 21 years (1975-1996), using relevant statistical tools. In agreement with the theoretical prediction, we found that sexual selection increased risks of local extinction (dichromatic birds had on average a 23% higher local extinction rate than monochromatic species). However, despite higher local extinction probabilities, the number of dichromatic species did not decrease over the period considered in this study. This pattern was caused by higher local turnover rates of dichromatic species, resulting in relatively stable communities for both groups of species. Our results suggest that these communities function as metacommunities, with frequent local extinctions followed by colonization. Anthropogenic factors impeding dispersal might therefore have a significant impact on the global persistence of sexually selected species.

The Amnesiac Lookback Option: Selectively Monitored Lookback Options and Cryptocurrencies

Directory of Open Access Journals (Sweden)

Ho-Chun Herbert Chang

2018-05-01

Full Text Available This study proposes a strategy to make the lookback option cheaper and more practical, and suggests the use of its properties to reduce risk exposure in cryptocurrency markets through blockchain enforced smart contracts and correct for informational inefficiencies surrounding prices and volatility. This paper generalizes partial, discretely-monitored lookback options that dilute premiums by selecting a subset of specified periods to determine payoff, which we call amnesiac lookback options. Prior literature on discretely-monitored lookback options considers the number of periods and assumes equidistant lookback periods in pricing partial lookback options. This study by contrast considers random sampling of lookback periods and compares resulting payoff of the call, put and spread options under floating and fixed strikes. Amnesiac lookbacks are priced with Monte Carlo simulations of Gaussian random walks under equidistant and random periods. Results are compared to analytic and binomial pricing models for the same derivatives. Simulations show diminishing marginal increases to the fair price as the number of selected periods is increased. The returns correspond to a Hill curve whose parameters are set by interest rate and volatility. We demonstrate over-pricing under equidistant monitoring assumptions with error increasing as the lookback periods decrease. An example of a direct implication for event trading is when shock is forecasted but its timing uncertain, equidistant sampling produces a lower error on the true maximum than random choice. We conclude that the instrument provides an ideal space for investors to balance their risk, and as a prime candidate to hedge extreme volatility. We discuss the application of the amnesiac lookback option and path-dependent options to cryptocurrencies and blockchain commodities in the context of smart contracts.

Acute Phase Proteins and their Relation to Energy Metabolites in Dairy Cows during the Pre- and Postpartal Period

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Gabriel Kováč

2009-01-01

Full Text Available The objective of this study was to evaluate the concentrations of selected acute phase proteins – haptoglobin (Hp and serum amyloid A (SAA, and selected variables of energy metabolism in blood serum of dairy cows during different stages of the pre- and postpartal period. The analyses were performed in dairy cows of the Slovak spotted breed and its crossbreeds (n = 57. The cows were divided into 9 groups according to the evaluated part of reproduction cycle – from 4 weeks before parturition to 10 weeks after parturition. Significant differences were found in mean Hp and SAA concentrations during the monitored period (P P P P P P P < 0.001. Moreover, significant correlations were found between Hp and non-esterified fatty acids, Hp and β-hydroxybutyrate, as well as between SAA and non-esterified fatty acids. Our results indicate that the acute phase response occurs in cows around parturition, and suggest that there are relationships between mediators of immune response and several indices of energy metabolism. Our results also suggest that in cows with higher concentrations of non-esterified fatty acids, indicating a certain degree of lipid mobilisation, higher values of acute phase proteins may be found.

Nutrition Report Cards: an opportunity to improve school lunch selection.

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Brian Wansink

Full Text Available OBJECTIVE: To explore the feasibility and implementation efficiency of Nutritional Report Cards (NRCs in helping children make healthier food choices at school. METHODS: Pilot testing was conducted in a rural New York school district (K-12. Over a five-week period, 27 parents received a weekly e-mail containing a NRC listing how many meal components (fruits, vegetables, starches, milk, snacks, and a-la-carte foods their child selected. We analyzed choices of students in the NRC group vs. the control group, both prior to and during the intervention period. Point-of-sale system data for a-la-carte items was analyzed using Generalized Least Squares regressions with clustered standard errors. RESULTS: NRCs encouraged more home conversations about nutrition and more awareness of food selections. Despite the small sample, the NRC was associated with reduced selection of some items, such as the percentage of those selecting cookies which decreased from 14.3 to 6.5 percent. Additionally, despite requiring new keys on the check-out registers to generate the NRC, checkout times increased by only 0.16 seconds per transaction, and compiling and sending the NRCs required a total weekly investment of 30 minutes of staff time. CONCLUSIONS: This test of concept suggests that NRCs are a feasible and inexpensive tool to guide children towards healthier choices.

Event-Related Potentials (ERPs) in Second Language Research: A Brief Introduction to the Technique, a Selected Review, and an Invitation to Reconsider Critical Periods in L2

Science.gov (United States)

Steinhauer, Karsten

2014-01-01

This article provides a selective overview of recent event-related brain potential (ERP) studies in L2 morpho-syntax, demonstrating that the ERP evidence supporting the critical period hypothesis (CPH) may be less compelling than previously thought. The article starts with a general introduction to ERP methodology and language-related ERP profiles…

Theoretical growth rates, periods, and pulsation constants for long-period variables

International Nuclear Information System (INIS)

Fox, M.W.; Wood, P.R.

1982-01-01

Theoretical values of the growth rate, period, and pulsation constant for the first three radial pulsation modes in red giants (Population II and galactic disk) and supergiants have been derived in the linear, nonadiabatic approximation. The effects of altering the surface boundary conditions, the effective temperature (or mixing length), and the opacity in the outer layers have been explored. In the standard models, the Q-value for the first overtone can be much larger (Q 1 1 roughly-equal0.04); in addition, the Q-value for the fundamental mode is reduced from previous values, as is the period ratio P 0 /P 1 . The growth rate for the fundamental mode is found to increase with luminosity on the giant branch while the growth rate for the first overtone decreases. Dynamical instabilities found in previous adiabatic models of extreme red giants do not occur when nonadiabatic effects are included in the models. In some massive, luminous models, period ratios P 0 /P 1 approx.7 occur when P 0 approx.2000--5000 days; it is suggested that the massive galactic supergiants and carbon stars which have secondary periods Papprox.2000--7000 days and primary periods Papprox.300--700 days are first-overtone pulsators in which the long secondary periods are due to excitation of the fundamental mode. Some other consequences of the present results are briefly discussed, with particular emphasis on the mode of pulsation of the Mira variables. Subject headings: stars: long-period variables: stars: pulsation: stars: supergiants

Quasi-periodicity in deep redshift surveys

International Nuclear Information System (INIS)

Weygaert, R. van de

1991-01-01

The recent result by Broadhurst et al., (1990. Nature 343, 726) showing a striking, nearly periodic, galaxy redshift distribution in a narrow pencil-beam survey, is explained within the Voronoi cellular model of clustering of galaxies. Galaxies, whose luminosities are selected from a Schechter luminosity function, are placed randomly within the walls of this cellular model. Narrow and deep, magnitude-limited, pencil-beam surveys through these structures are simulated. Some 15 per cent of these beams show that observed regular pattern, with a spacing between the peaks of the order of 105 h -1 -150 h -1 Mpc, but most pencil-beams show peaks in the redshift distribution without periodicity, so we may conclude that, even within a cellular universe, periodicity is not a common phenomenon. (author)

SALES PROMOTION, A SUGGESTED ADULT DISTRIBUTIVE EDUCATION COURSE OUTLINE.

Science.gov (United States)

RUBIN, ALAN J.; AND OTHERS

THIS SUGGESTED OUTLINE FOR A BASIC COURSE IN SALES PROMOTION IS DESIGNED FOR NOT LESS THAN FIVE 2-HOUR SESSIONS ON (1) ASPECTS OF SALES PROMOTION, (2) SALES PROMOTION TECHNIQUES, (3) NEWSPAPER ADVERTISING, (4) WINDOW AND INTERIOR DISPLAY PRINCIPLES, AND (5) SELECTED PROMOTIONAL MEDIA AND DEVICES. POSSIBLE TEACHERS INCLUDE A SALES PROMOTION…

Market timing and selectivity performance of mutual funds in Ghana

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Abubakar Musah

2014-07-01

Full Text Available The growing interest in mutual funds in Ghana has been tremendous over the last decade as evidenced by the continuous increases in number and total funds under management. However, no empirical work has been done on the selectivity and timing ability of the mutual fund managers. Using monthly returns data hand-collected from the reports of the mutual fund managers for the period January 2007-December 2012, this paper examines the market timing and selectivity ability of mutual fund managers in Ghana using the classic Treynor-Mazuy (1966 model and Henriksson- Merton (1981 model. The results suggest that, in general mutual fund managers in Ghana are not able to effectively select stocks and also are not able to predict both the magnitude and direction of future market returns. More specifically, all of the sample mutual fund managers attain significant negative selectivity coefficients and also most of them attain insignificant negative timing coefficients.

Scattering analysis of periodic structures using finite-difference time-domain

CERN Document Server

ElMahgoub, Khaled; Elsherbeni, Atef Z

2012-01-01

Periodic structures are of great importance in electromagnetics due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap (EBG) structures, periodic absorbers, meta-materials, and many others. The aim of this book is to develop efficient computational algorithms to analyze the scattering properties of various electromagnetic periodic structures using the finite-difference time-domain periodic boundary condition (FDTD/PBC) method. A new FDTD/PBC-based algorithm is introduced to analyze general skewed grid periodic structures while another algor

Phenology of Scramble Polygyny in a Wild Population of Chrysolemid Beetles: The Opportunity for and the Strength of Sexual Selection

Science.gov (United States)

Baena, Martha Lucía; Macías-Ordóñez, Rogelio

2012-01-01

Recent debate has highlighted the importance of estimating both the strength of sexual selection on phenotypic traits, and the opportunity for sexual selection. We describe seasonal fluctuations in mating dynamics of Leptinotarsa undecimlineata (Coleoptera: Chrysomelidae). We compared several estimates of the opportunity for, and the strength of, sexual selection and male precopulatory competition over the reproductive season. First, using a null model, we suggest that the ratio between observed values of the opportunity for sexual selections and their expected value under random mating results in unbiased estimates of the actual nonrandom mating behavior of the population. Second, we found that estimates for the whole reproductive season often misrepresent the actual value at any given time period. Third, mating differentials on male size and mobility, frequency of male fighting and three estimates of the opportunity for sexual selection provide contrasting but complementary information. More intense sexual selection associated to male mobility, but not to male size, was observed in periods with high opportunity for sexual selection and high frequency of male fights. Fourth, based on parameters of spatial and temporal aggregation of female receptivity, we describe the mating system of L. undecimlineata as a scramble mating polygyny in which the opportunity for sexual selection varies widely throughout the season, but the strength of sexual selection on male size remains fairly weak, while male mobility inversely covaries with mating success. We suggest that different estimates for the opportunity for, and intensity of, sexual selection should be applied in order to discriminate how different behavioral and demographic factors shape the reproductive dynamic of populations. PMID:22761675

Using suggestion to model different types of automatic writing.

Science.gov (United States)

Walsh, E; Mehta, M A; Oakley, D A; Guilmette, D N; Gabay, A; Halligan, P W; Deeley, Q

2014-05-01

Our sense of self includes awareness of our thoughts and movements, and our control over them. This feeling can be altered or lost in neuropsychiatric disorders as well as in phenomena such as "automatic writing" whereby writing is attributed to an external source. Here, we employed suggestion in highly hypnotically suggestible participants to model various experiences of automatic writing during a sentence completion task. Results showed that the induction of hypnosis, without additional suggestion, was associated with a small but significant reduction of control, ownership, and awareness for writing. Targeted suggestions produced a double dissociation between thought and movement components of writing, for both feelings of control and ownership, and additionally, reduced awareness of writing. Overall, suggestion produced selective alterations in the control, ownership, and awareness of thought and motor components of writing, thus enabling key aspects of automatic writing, observed across different clinical and cultural settings, to be modelled. Copyright © 2014. Published by Elsevier Inc.

Positive evolutionary selection of an HD motif on Alzheimer precursor protein orthologues suggests a functional role.

Science.gov (United States)

Miklós, István; Zádori, Zoltán

2012-02-01

HD amino acid duplex has been found in the active center of many different enzymes. The dyad plays remarkably different roles in their catalytic processes that usually involve metal coordination. An HD motif is positioned directly on the amyloid beta fragment (Aβ) and on the carboxy-terminal region of the extracellular domain (CAED) of the human amyloid precursor protein (APP) and a taxonomically well defined group of APP orthologues (APPOs). In human Aβ HD is part of a presumed, RGD-like integrin-binding motif RHD; however, neither RHD nor RXD demonstrates reasonable conservation in APPOs. The sequences of CAEDs and the position of the HD are not particularly conserved either, yet we show with a novel statistical method using evolutionary modeling that the presence of HD on CAEDs cannot be the result of neutral evolutionary forces (pHD motif is underrepresented in the proteomes of all species of the animal kingdom. Position migration can be explained by high probability occurrence of multiple copies of HD on intermediate sequences, from which only one is kept by selective evolutionary forces, in a similar way as in the case of the "transcription binding site turnover." CAED of all APP orthologues and homologues are predicted to bind metal ions including Amyloid-like protein 1 (APLP1) and Amyloid-like protein 2 (APLP2). Our results suggest that HDs on the CAEDs are most probably key components of metal-binding domains, which facilitate and/or regulate inter- or intra-molecular interactions in a metal ion-dependent or metal ion concentration-dependent manner. The involvement of naturally occurring mutations of HD (Tottori (D7N) and English (H6R) mutations) in early onset Alzheimer's disease gives additional support to our finding that HD has an evolutionary preserved function on APPOs.

İşveren Markası Yönetimi Sürecinde İşe Alım Öncesi Dönem ve İşgören Seçimi: Kavramsal Bir Değerlendirme (Pre-Recruitment Period and Employee Selection in Employer Brand Management Process: A Conceptual Evaluation

Directory of Open Access Journals (Sweden)

Ebru GÖZEN

2016-03-01

Full Text Available Nowadays constantly renewing itself technological , socio-economic and cultural changes have dragged the companies to the tight competition. They can sustain their assets depends on finding the right labor and employment abilities. The quality and success of the human resources departments mostly depends on the process of finding employee. This process forms the basis of the other HR processes. One of the components of employer branding is Pre-Recruitment Period and Employee Selection. In this study, pre- recruitment and employee selection process is presented from the perspective of employer brand management. On this basis, it’s targeted to make suggestions for future researchers. The literature on this subject is very limited in our country. So this study is important to contribute to the literature

Sex and ancestry determine the free-running circadian period.

Science.gov (United States)

Eastman, Charmane I; Tomaka, Victoria A; Crowley, Stephanie J

2017-10-01

The endogenous, free-running circadian period (τ) determines the phase relationship that an organism assumes when entrained to the 24-h day. We found a shorter circadian period in African Americans compared to non-Hispanic European Americans (24.07 versus 24.33 h). We speculate that a short circadian period, closer to 24 h, was advantageous to humans living around the equator, but when humans migrated North out of Africa, where the photoperiod changes with seasons, natural selection favoured people with longer circadian periods. Recently, in evolutionary terms, immigrants came from Europe and Africa to America ('the New World'). The Europeans were descendents of people who had lived in Europe for thousands of years with changing photoperiods (and presumably longer periods), whereas Africans had ancestors who had always lived around the equator (with shorter periods). It may have been advantageous to have a longer circadian period while living in Europe early in the evolution of humans. In our modern world, however, it is better to have a shorter period, because it helps make our circadian rhythms earlier, which is adaptive in our early-bird-dominated society. European American women had a shorter circadian period than men (24.24 versus 24.41), but there was no sex difference in African Americans (24.07 for both men and women). We speculate that selection pressures in Europe made men develop a slightly longer period than women to help them track dawn which could be useful for hunters, but less important for women as gatherers. © 2017 The Authors. Journal of Sleep Research published by John Wiley & Sons Ltd on behalf of European Sleep Research Society.

Ancient Egyptian mummy genomes suggest an increase of Sub-Saharan African ancestry in post-Roman periods

Science.gov (United States)

Schuenemann, Verena J.; Peltzer, Alexander; Welte, Beatrix; van Pelt, W. Paul; Molak, Martyna; Wang, Chuan-Chao; Furtwängler, Anja; Urban, Christian; Reiter, Ella; Nieselt, Kay; Teßmann, Barbara; Francken, Michael; Harvati, Katerina; Haak, Wolfgang; Schiffels, Stephan; Krause, Johannes

2017-01-01

Egypt, located on the isthmus of Africa, is an ideal region to study historical population dynamics due to its geographic location and documented interactions with ancient civilizations in Africa, Asia and Europe. Particularly, in the first millennium BCE Egypt endured foreign domination leading to growing numbers of foreigners living within its borders possibly contributing genetically to the local population. Here we present 90 mitochondrial genomes as well as genome-wide data sets from three individuals obtained from Egyptian mummies. The samples recovered from Middle Egypt span around 1,300 years of ancient Egyptian history from the New Kingdom to the Roman Period. Our analyses reveal that ancient Egyptians shared more ancestry with Near Easterners than present-day Egyptians, who received additional sub-Saharan admixture in more recent times. This analysis establishes ancient Egyptian mummies as a genetic source to study ancient human history and offers the perspective of deciphering Egypt's past at a genome-wide level. PMID:28556824

Hypnosis, suggestion, and suggestibility: an integrative model.

Science.gov (United States)

Lynn, Steven Jay; Laurence, Jean-Roch; Kirsch, Irving

2015-01-01

This article elucidates an integrative model of hypnosis that integrates social, cultural, cognitive, and neurophysiological variables at play both in and out of hypnosis and considers their dynamic interaction as determinants of the multifaceted experience of hypnosis. The roles of these variables are examined in the induction and suggestion stages of hypnosis, including how they are related to the experience of involuntariness, one of the hallmarks of hypnosis. It is suggested that studies of the modification of hypnotic suggestibility; cognitive flexibility; response sets and expectancies; the default-mode network; and the search for the neurophysiological correlates of hypnosis, more broadly, in conjunction with research on social psychological variables, hold much promise to further understanding of hypnosis.

Optimal sampling period of the digital control system for the nuclear power plant steam generator water level control

International Nuclear Information System (INIS)

Hur, Woo Sung; Seong, Poong Hyun

1995-01-01

A great effort has been made to improve the nuclear plant control system by use of digital technologies and a long term schedule for the control system upgrade has been prepared with an aim to implementation in the next generation nuclear plants. In case of digital control system, it is important to decide the sampling period for analysis and design of the system, because the performance and the stability of a digital control system depend on the value of the sampling period of the digital control system. There is, however, currently no systematic method used universally for determining the sampling period of the digital control system. Generally, a traditional way to select the sampling frequency is to use 20 to 30 times the bandwidth of the analog control system which has the same system configuration and parameters as the digital one. In this paper, a new method to select the sampling period is suggested which takes into account of the performance as well as the stability of the digital control system. By use of the Irving's model steam generator, the optimal sampling period of an assumptive digital control system for steam generator level control is estimated and is actually verified in the digital control simulation system for Kori-2 nuclear power plant steam generator level control. Consequently, we conclude the optimal sampling period of the digital control system for Kori-2 nuclear power plant steam generator level control is 1 second for all power ranges. 7 figs., 3 tabs., 8 refs. (Author)

Multiple bottlenecks in hierarchical control of action sequences: what does "response selection" select in skilled typewriting?

Science.gov (United States)

Yamaguchi, Motonori; Logan, Gordon D; Li, Vanessa

2013-08-01

Does response selection select words or letters in skilled typewriting? Typing performance involves hierarchically organized control processes: an outer loop that controls word level processing, and an inner loop that controls letter (or keystroke) level processing. The present study addressed whether response selection occurs in the outer loop or the inner loop by using the psychological refractory period (PRP) paradigm in which Task1 required typing single words and Task2 required vocal responses to tones. The number of letters (string length) in the words was manipulated to discriminate selection of words from selection of keystrokes. In Experiment 1, the PRP effect depended on string length of words in Task1, suggesting that response selection occurs in the inner loop. To assess contributions of the outer loop, the influence of string length was examined in a lexical-decision task that also involves word encoding and lexical access (Experiment 2), or to-be-typed words were preexposed so outer-loop processing could finish before typing started (Experiment 3). Response time for Task2 (RT2) did not depend on string length with lexical decision, and RT2 still depended on string length with typing preexposed strings. These results support the inner-loop locus of the PRP effect. In Experiment 4, typing was performed as Task2, and the effect of string length on typing RT interacted with stimulus onset asynchrony superadditively, implying that another bottleneck also exists in the outer loop. We conclude that there are at least two bottleneck processes in skilled typewriting. 2013 APA, all rights reserved

Migrant Selection and the Health of U.S. Immigrants From the Former Soviet Union

Science.gov (United States)

Elo, Irma T.

2012-01-01

Few prior studies have investigated the health of U.S. immigrants from the former Soviet Union (FSU). Utilizing data from the 2000 U.S. census and the 2000–2007 National Health Interview Survey (NIHS), we compare levels of disability of FSU immigrants with U.S.-born whites (ages 50–84). Our findings suggest an “epidemiologic paradox” in that FSU immigrants possess higher levels of education compared with U.S.-born whites, but report considerably higher disability with and without adjustment for education. Nonetheless, FSU immigrants report lower levels of smoking and heavy alcohol use compared with U.S.-born whites. We further investigate disability by period of arrival among FSU immigrants. Changes in Soviet emigration policies conceivably altered the level of health selectivity among émigrés. We find evidence that FSU immigrants who emigrated during a period when a permission to emigrate was hard to obtain (1970–1986) displayed less disability compared with those who emigrated when these restrictions were less stringent (1987–2000). Finally, we compare disability among Russian-born U.S. immigrants with that of those residing in Russia as a direct test of health selectivity. We find that Russian immigrants report lower levels of disability compared with Russians in Russia, suggesting that they are positively selected for health despite their poor health relative to U.S.-born whites. PMID:22421810

Selective Predation of a Stalking Predator on Ungulate Prey.

Directory of Open Access Journals (Sweden)

Marco Heurich

Full Text Available Prey selection is a key factor shaping animal populations and evolutionary dynamics. An optimal forager should target prey that offers the highest benefits in terms of energy content at the lowest costs. Predators are therefore expected to select for prey of optimal size. Stalking predators do not pursue their prey long, which may lead to a more random choice of prey individuals. Due to difficulties in assessing the composition of available prey populations, data on prey selection of stalking carnivores are still scarce. We show how the stalking predator Eurasian lynx (Lynx lynx selects prey individuals based on species identity, age, sex and individual behaviour. To address the difficulties in assessing prey population structure, we confirm inferred selection patterns by using two independent data sets: (1 data of 387 documented kills of radio-collared lynx were compared to the prey population structure retrieved from systematic camera trapping using Manly's standardized selection ratio alpha and (2 data on 120 radio-collared roe deer were analysed using a Cox proportional hazards model. Among the larger red deer prey, lynx selected against adult males-the largest and potentially most dangerous prey individuals. In roe deer lynx preyed selectively on males and did not select for a specific age class. Activity during high risk periods reduced the risk of falling victim to a lynx attack. Our results suggest that the stalking predator lynx actively selects for size, while prey behaviour induces selection by encounter and stalking success rates.

12000 rotation periods of Kepler stars (Nielsen+, 2013)

DEFF Research Database (Denmark)

Nielsen, M. B.; Gizon, L.; Schunker, H.

2013-01-01

Rotation periods of 12253 stars in the Kepler field. The periods are determined by the brightness variations, from star spots or active regions, in the light curves of the white light photometry obtained by the Kepler spacecraft. The median absolute deviation from the median (MAD) of the periods...... shows the scatter of periods for each star, over 6 or more (out of 8 analyzed) Kepler quarters. The g-r color index, E(B-V), radius, surface gravity, and effective temperature are from the Kepler Input Catalog (KIC). Column 9 (TF) indicates whether or not the msMAP data for a given star satisfies...... the selection criteria described in section 2. Of these, there are 86 stars with periods from the msMAP data that differ from the period derived from the PDCMAP data by more than one frequency resolution element (1/90d-1). For these stars the msMAP periods are therefore given in column 10 as a none-zero value...

Selective interference reveals dissociation between memory for location and colour.

Science.gov (United States)

Vuontela, V; Rämä, P; Raninen, A; Aronen, H J; Carlson, S

1999-08-02

The aim was to study whether there is indication of a dissociation in processing of visuospatial and colour information in working memory in humans. Experimental subjects performed visuospatial and colour n-back tasks with and without visuospatial and colour distractive stimuli presented in the middle of the delay period to specifically affect mnemonic processing of task-related information. In the high memory-load condition, the visuospatial, but not the colour, task was selectively disrupted by visuospatial but not colour distractors. When subvocal rehearsal of the memoranda in the colour task was prevented by articulatory suppression; colour task performance was also selectively disrupted by distractors qualitatively similar to the memoranda. The results support the suggestion that visual working memory for location is processed separate from that for colour.

Effect of different periods of chronic heat stress with or without vitamin C supplementation on bone and selected serum parameters of broiler chickens.

Science.gov (United States)

Mosleh, Najmeh; Shomali, Tahoora; Nematollahi, Fahimeh; Ghahramani, Zahra; Ahrari Khafi, Mohammad Saeid; Namazi, Fatemeh

2018-04-01

This study evaluates the effect of different periods of chronic heat stress (CHS) on selected bone and serum parameters of broiler chickens with or without vitamin C administration. Ninety 23-day-old chickens were randomly allocated into seven groups: (1) control, (2) short-term CHS (5 days), (3) short-term CHS + vitamin C (12 g/100 l drinking water of a 50% product), (4) medium-term CHS (10 days), (5) medium-term CHS + vitamin C, (6) long-term CHS (20 days) and (7) long-term CHS + vitamin C. In heat-stressed groups the temperature was increased to 39 ± 1°C for 8 h/day. At the end of the experiment, blood samples were collected and shank, keel and tibia bones were removed. CHS was not associated with a drastic change in serum Ca and corticosterone, or bone characteristics (both cortical and trabecular bones in radiographical and histological evaluation), or birds' performance. Oxidative stress was present especially with short-term CHS. CHS, especially for short or medium periods, showed a tendency to increase serum vitamin C and administration of this vitamin did not make a significant change in its serum levels although it ameliorated oxidative stress. In conclusion, it seems that CHS is not associated with an appreciable change in broiler performance, bone characteristics, or selected serum parameters; and simultaneous vitamin C administration at the dosage of 12 g/100 l in drinking water has no beneficial effect apart from reducing oxidative stress especially in short-term chronically heat-stressed birds.

Measuring viability of pacs during reform period in Maharashtra: A case study

OpenAIRE

Shah, Deepak

2007-01-01

The study showed a reduction in the operational efficiency of the selected PACS during the post-economic reform period as against the pre-economic reform period. The operational efficiency was measured in respect of various liquidity ratio, profitability ratios and financial leverage ratios. Not only the selected societies showed a decline in their current ratio, rate of return on assets, return on owner’s equity and Marginal Efficiency of Capital (MEC) but also showed higher dependency on le...

Gene Expression Profiling in the Pituitary Gland of Laying Period and Ceased Period Huoyan Geese

Directory of Open Access Journals (Sweden)

Xinhong Luan

2013-07-01

Full Text Available Huoyan goose is a Chinese local breed famous for its higher laying performance, but the problems of variety degeneration have emerged recently, especially a decrease in the number of eggs laid. In order to better understand the molecular mechanism that underlies egg laying in Huoyan geese, gene profiles in the pituitary gland of Huoyan geese taken during the laying period and ceased period were investigated using the suppression subtractive hybridization (SSH method. Total RNA was extracted from pituitary glands of ceased period and laying period geese. The cDNA in the pituitary glands of ceased geese was subtracted from the cDNA in the pituitary glands of laying geese (forward subtraction; the reverse subtraction was also performed. After sequencing and annotation, a total of 30 and 24 up and down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These genes mostly related to biosynthetic process, cellular nitrogen compound metabolic process, transport, cell differentiation, cellular protein modification process, signal transduction, small molecule metabolic process. Furthermore, eleven genes were selected for further analyses by quantitative real-time PCR (qRT-PCR. The qRT-PCR results for the most part were consistent with the SSH results. Among these genes, Synaptotagmin-1 (SYT1 and Stathmin-2 (STMN2 were substantially over-expressed in laying period compared to ceased period. These results could serve as an important reference for elucidating the molecular mechanism of higher laying performance in Huoyan geese.

Types of suggestibility: Relationships among compliance, indirect, and direct suggestibility.

Science.gov (United States)

Polczyk, Romuald; Pasek, Tomasz

2006-10-01

It is commonly believed that direct suggestibility, referring to overt influence, and indirect suggestibility, in which the intention to influence is hidden, correlate poorly. This study demonstrates that they are substantially related, provided that they tap similar areas of influence. Test results from 103 students, 55 women and 48 men, were entered into regression analyses. Indirect suggestibility, as measured by the Sensory Suggestibility Scale for Groups, and compliance, measured by the Gudjonsson Compliance Scale, were predictors of direct suggestibility, assessed with the Barber Suggestibility Scale. Spectral analyses showed that indirect suggestibility is more related to difficult tasks on the BSS, but compliance is more related to easy tasks on this scale.

On nonlinear periodic drift waves

International Nuclear Information System (INIS)

Kauschke, U.; Schlueter, H.

1990-09-01

Nonlinear periodic drift waves are investigated on the basis of a simple perturbation scheme for both the amplitude and inverse frequency. The coefficients for the generation of the forced harmonics are derived, a nonlinear dispersion relation is suggested and a criterion for the onset of the modulational instability is obtained. The results are compared with the ones obtained with the help of a standard KBM-treatment. Moreover cnoidal drift waves are suggested and compared to an experimental observation. (orig.)

Dinosaur peptides suggest mechanisms of protein survival.

Science.gov (United States)

San Antonio, James D; Schweitzer, Mary H; Jensen, Shane T; Kalluri, Raghu; Buckley, Michael; Orgel, Joseph P R O

2011-01-01

Eleven collagen peptide sequences recovered from chemical extracts of dinosaur bones were mapped onto molecular models of the vertebrate collagen fibril derived from extant taxa. The dinosaur peptides localized to fibril regions protected by the close packing of collagen molecules, and contained few acidic amino acids. Four peptides mapped to collagen regions crucial for cell-collagen interactions and tissue development. Dinosaur peptides were not represented in more exposed parts of the collagen fibril or regions mediating intermolecular cross-linking. Thus functionally significant regions of collagen fibrils that are physically shielded within the fibril may be preferentially preserved in fossils. These results show empirically that structure-function relationships at the molecular level could contribute to selective preservation in fossilized vertebrate remains across geological time, suggest a 'preservation motif', and bolster current concepts linking collagen structure to biological function. This non-random distribution supports the hypothesis that the peptides are produced by the extinct organisms and suggests a chemical mechanism for survival.

Dinosaur Peptides Suggest Mechanisms of Protein Survival

Energy Technology Data Exchange (ETDEWEB)

San Antonio, James D.; Schweitzer, Mary H.; Jensen, Shane T.; Kalluri, Raghu; Buckley, Michael; Orgel, Joseph P.R.O. (Harvard-Med); (IIT); (NCSU); (UPENN); (Manchester); (Orthovita)

2011-09-16

Eleven collagen peptide sequences recovered from chemical extracts of dinosaur bones were mapped onto molecular models of the vertebrate collagen fibril derived from extant taxa. The dinosaur peptides localized to fibril regions protected by the close packing of collagen molecules, and contained few acidic amino acids. Four peptides mapped to collagen regions crucial for cell-collagen interactions and tissue development. Dinosaur peptides were not represented in more exposed parts of the collagen fibril or regions mediating intermolecular cross-linking. Thus functionally significant regions of collagen fibrils that are physically shielded within the fibril may be preferentially preserved in fossils. These results show empirically that structure-function relationships at the molecular level could contribute to selective preservation in fossilized vertebrate remains across geological time, suggest a 'preservation motif', and bolster current concepts linking collagen structure to biological function. This non-random distribution supports the hypothesis that the peptides are produced by the extinct organisms and suggests a chemical mechanism for survival.

Confusion in the Periodic Table of the Elements.

Science.gov (United States)

Fernelius, W. C.; Powell, W. H.

1982-01-01

Discusses long (expanded), short (condensed), and pyramidal periodic table formats and documents events leading to a periodic table in which subgroups (families) are designated with the letters A and B, suggesting that this format is confusing for those consulting the table. (JN)

Otolaryngology residency selection process. Medical student perspective.

Science.gov (United States)

Stringer, S P; Cassisi, N J; Slattery, W H

1992-04-01

In an effort to improve the otolaryngology matching process at the University of Florida, Gainesville, we sought to obtain the medical student's perspective of the current system. All students who interviewed here over a 3-year period were surveyed regarding the application, interview, and ranking process. In addition, suggestions for improving the system were sought from the students. The application and interviewing patterns of the students surveyed were found to be similar to those of the entire otolaryngology residency applicant pool. We were unable to identify any factors that influence a student's rank list that could be prospectively used to help select applicants for interview. A variety of suggestions for improvements in the match were received, several of which could easily be instituted. A uniform interview invitation date as requested by the students could be rapidly implemented and would provide benefits for both the students and the residency programs.

Genome-wide analysis suggests high level of microsynteny and purifying selection affect the evolution of EIN3/EIL family in Rosaceae.

Science.gov (United States)

Cao, Yunpeng; Han, Yahui; Meng, Dandan; Li, Dahui; Jin, Qing; Lin, Yi; Cai, Yongping

2017-01-01

The ethylene-insensitive3/ethylene-insensitive3-like ( EIN3/EIL ) proteins are a type of nuclear-localized protein with DNA-binding activity in plants. Although the EIN3/EIL gene family has been studied in several plant species, little is known about comprehensive study of the EIN3/EIL gene family in Rosaceae. In this study, ten, five, four, and five EIN3/EIL genes were identified in the genomes of pear ( Pyrus bretschneideri ), mei ( Prunus mume ), peach ( Prunus persica ) and strawberry ( Fragaria vesca ), respectively. Twenty-eight chromosomal segments of EIL/EIN3 gene family were found in four Rosaceae species, and these segments could form seven orthologous or paralogous groups based on interspecies or intraspecies gene colinearity (microsynteny) analysis. Moreover, the highly conserved regions of microsynteny were found in four Rosaceae species. Subsequently it was found that both whole genome duplication and tandem duplication events significantly contributed to the EIL/EIN3 gene family expansion. Gene expression analysis of the EIL/EIN3 genes in the pear revealed subfunctionalization for several PbEIL genes derived from whole genome duplication. It is noteworthy that according to environmental selection pressure analysis, the strong purifying selection should dominate the maintenance of the EIL/EIN3 gene family in four Rosaceae species. These results provided useful information on Rosaceae EIL/EIN3 genes, as well as insights into the evolution of this gene family in four Rosaceae species. Furthermore, high level of microsynteny in the four Rosaceae plants suggested that a large-scale genome duplication event in the EIL/EIN3 gene family was predated to speciation.

Genome-wide analysis suggests high level of microsynteny and purifying selection affect the evolution of EIN3/EIL family in Rosaceae

Directory of Open Access Journals (Sweden)

Yunpeng Cao

2017-05-01

Full Text Available The ethylene-insensitive3/ethylene-insensitive3-like (EIN3/EIL proteins are a type of nuclear-localized protein with DNA-binding activity in plants. Although the EIN3/EIL gene family has been studied in several plant species, little is known about comprehensive study of the EIN3/EIL gene family in Rosaceae. In this study, ten, five, four, and five EIN3/EIL genes were identified in the genomes of pear (Pyrus bretschneideri, mei (Prunus mume, peach (Prunus persica and strawberry (Fragaria vesca, respectively. Twenty-eight chromosomal segments of EIL/EIN3 gene family were found in four Rosaceae species, and these segments could form seven orthologous or paralogous groups based on interspecies or intraspecies gene colinearity (microsynteny analysis. Moreover, the highly conserved regions of microsynteny were found in four Rosaceae species. Subsequently it was found that both whole genome duplication and tandem duplication events significantly contributed to the EIL/EIN3 gene family expansion. Gene expression analysis of the EIL/EIN3 genes in the pear revealed subfunctionalization for several PbEIL genes derived from whole genome duplication. It is noteworthy that according to environmental selection pressure analysis, the strong purifying selection should dominate the maintenance of the EIL/EIN3 gene family in four Rosaceae species. These results provided useful information on Rosaceae EIL/EIN3 genes, as well as insights into the evolution of this gene family in four Rosaceae species. Furthermore, high level of microsynteny in the four Rosaceae plants suggested that a large-scale genome duplication event in the EIL/EIN3 gene family was predated to speciation.

Absence of positive selection on CenH3 in Luzula suggests that holokinetic chromosomes may suppress centromere drive.

Science.gov (United States)

Zedek, František; Bureš, Petr

2016-12-01

The centromere drive theory explains diversity of eukaryotic centromeres as a consequence of the recurrent conflict between centromeric repeats and centromeric histone H3 (CenH3), in which selfish centromeres exploit meiotic asymmetry and CenH3 evolves adaptively to counterbalance deleterious consequences of driving centromeres. Accordingly, adaptively evolving CenH3 has so far been observed only in eukaryotes with asymmetric meiosis. However, if such evolution is a consequence of centromere drive, it should depend not only on meiotic asymmetry but also on monocentric or holokinetic chromosomal structure. Selective pressures acting on CenH3 have never been investigated in organisms with holokinetic meiosis despite the fact that holokinetic chromosomes have been hypothesized to suppress centromere drive. Therefore, the present study evaluates selective pressures acting on the CenH3 gene in holokinetic organisms for the first time, specifically in the representatives of the plant genus Luzula (Juncaceae), in which the kinetochore formation is not co-localized with any type of centromeric repeat. PCR, cloning and sequencing, and database searches were used to obtain coding CenH3 sequences from Luzula species. Codon substitution models were employed to infer selective regimes acting on CenH3 in Luzula KEY RESULTS: In addition to the two previously published CenH3 sequences from L. nivea, 16 new CenH3 sequences have been isolated from 12 Luzula species. Two CenH3 isoforms in Luzula that originated by a duplication event prior to the divergence of analysed species were found. No signs of positive selection acting on CenH3 in Luzula were detected. Instead, evidence was found that selection on CenH3 of Luzula might have been relaxed. The results indicate that holokinetism itself may suppress centromere drive and, therefore, holokinetic chromosomes might have evolved as a defence against centromere drive. © The Author 2016. Published by Oxford University Press on behalf of

The Reputation Driven Interplay of Relationships between Clients and Auditors in an Auditor Selection Process

DEFF Research Database (Denmark)

Kacanski, Slobodan

2017-01-01

This study investigates the reputation-based interplay between auditor selection and interlocking directorships from a multilevel network perspective. The aim of this article is to explore how and under what conditions reputation influences patterns of social selection processes in an assurance...... to the literature on auditor selection. A total of 774 annual reports were collected from 145 - 165 Danish public listed companies, and the relational data of companies was assembled, as comprised of the members of supervisory boards and partners who signed audit reports during the five-year period from 2010...... to 2014. In this study, mechanisms for auditor selection were controlled by mechanisms for interlocking directorships in order to obtain a broader picture of the conditions under which board members have tendencies to select reputable auditors. The findings suggest that reputation has a significant impact...

Inelastic spectra to predict period elongation of structures under earthquake loading

DEFF Research Database (Denmark)

Katsanos, Evangelos; Sextos, A.G.

2015-01-01

Period lengthening, exhibited by structures when subjected to strong ground motions, constitutes an implicit proxy of structural inelasticity and associated damage. However, the reliable prediction of the inelastic period is tedious and a multi-parametric task, which is related to both epistemic ...... for period lengthening as a function of Ry and Tel. These equations may be used in the framework of the earthquake record selection and scaling....

Phenology of scramble polygyny in a wild population of chrysomelid beetles: the opportunity for and the strength of sexual selection [corrected].

Directory of Open Access Journals (Sweden)

Martha Lucía Baena

Full Text Available Recent debate has highlighted the importance of estimating both the strength of sexual selection on phenotypic traits, and the opportunity for sexual selection. We describe seasonal fluctuations in mating dynamics of Leptinotarsa undecimlineata (Coleoptera: Chrysomelidae. We compared several estimates of the opportunity for, and the strength of, sexual selection and male precopulatory competition over the reproductive season. First, using a null model, we suggest that the ratio between observed values of the opportunity for sexual selections and their expected value under random mating results in unbiased estimates of the actual nonrandom mating behavior of the population. Second, we found that estimates for the whole reproductive season often misrepresent the actual value at any given time period. Third, mating differentials on male size and mobility, frequency of male fighting and three estimates of the opportunity for sexual selection provide contrasting but complementary information. More intense sexual selection associated to male mobility, but not to male size, was observed in periods with high opportunity for sexual selection and high frequency of male fights. Fourth, based on parameters of spatial and temporal aggregation of female receptivity, we describe the mating system of L. undecimlineata as a scramble mating polygyny in which the opportunity for sexual selection varies widely throughout the season, but the strength of sexual selection on male size remains fairly weak, while male mobility inversely covaries with mating success. We suggest that different estimates for the opportunity for, and intensity of, sexual selection should be applied in order to discriminate how different behavioral and demographic factors shape the reproductive dynamic of populations.

Reflections on Teaching Periodic Table Concepts: A Case Study of Selected Schools in South Africa

Science.gov (United States)

Mokiwa, Hamza Omari

2017-01-01

The Periodic Table of Elements is central to the study of modern Physics and Chemistry. It is however, considered by teachers as difficult to teach. This paper reports on a case study exploring reflections on teaching periodic table concepts in five secondary schools from South Africa. Qualitative methodology of interviews and document analysis…

Unified Digital Periodic Signal Filters for Power Converter Systems

DEFF Research Database (Denmark)

Yang, Yongheng; Xin, Zhen; Zhou, Keliang

2017-01-01

Periodic signal controllers like repetitive and resonant controllers have demonstrated much potential in the control of power electronic converters, where periodic signals (e.g., ac voltages and currents) can be precisely regulated to follow references. Beyond the control of periodic signals, ac...... signal processing (e.g., in synchronization and pre-filtering) is also very important for power converter systems. Hence, this paper serves to unify digital periodic signal filters so as to maximize their roles in power converter systems (e.g., enhance the control of ac signals). The unified digital...... periodic signal filters behave like a comb filter, but it can also be configured to selectively filter out the harmonics of interest (e.g., the odd-order harmonics in single-phase power converter systems). Moreover, a virtual variable-sampling-frequency unit delay that enables frequency adaptive periodic...

Phenotypic selection in natural populations: what limits directional selection?

Science.gov (United States)

Kingsolver, Joel G; Diamond, Sarah E

2011-03-01

Studies of phenotypic selection document directional selection in many natural populations. What factors reduce total directional selection and the cumulative evolutionary responses to selection? We combine two data sets for phenotypic selection, representing more than 4,600 distinct estimates of selection from 143 studies, to evaluate the potential roles of fitness trade-offs, indirect (correlated) selection, temporally varying selection, and stabilizing selection for reducing net directional selection and cumulative responses to selection. We detected little evidence that trade-offs among different fitness components reduced total directional selection in most study systems. Comparisons of selection gradients and selection differentials suggest that correlated selection frequently reduced total selection on size but not on other types of traits. The direction of selection on a trait often changes over time in many temporally replicated studies, but these fluctuations have limited impact in reducing cumulative directional selection in most study systems. Analyses of quadratic selection gradients indicated stabilizing selection on body size in at least some studies but provided little evidence that stabilizing selection is more common than disruptive selection for most traits or study systems. Our analyses provide little evidence that fitness trade-offs, correlated selection, or stabilizing selection strongly constrains the directional selection reported for most quantitative traits.

Comparison of Periodized and Non-Periodized Resistance Training on Maximal Strength: A Meta-Analysis.

Science.gov (United States)

Williams, Tyler D; Tolusso, Danilo V; Fedewa, Michael V; Esco, Michael R

2017-10-01

Periodization is a logical method of organizing training into sequential phases and cyclical time periods in order to increase the potential for achieving specific performance goals while minimizing the potential for overtraining. Periodized resistance training plans are proposed to be superior to non-periodized training plans for enhancing maximal strength. The primary aim of this study was to examine the previous literature comparing periodized resistance training plans to non-periodized resistance training plans and determine a quantitative estimate of effect on maximal strength. All studies included in the meta-analysis met the following inclusion criteria: (1) peer-reviewed publication; (2) published in English; (3) comparison of a periodized resistance training group to a non-periodized resistance training group; (4) maximal strength measured by 1-repetition maximum (1RM) squat, bench press, or leg press. Data were extracted and independently coded by two authors. Random-effects models were used to aggregate a mean effect size (ES), 95% confidence intervals (CIs) and potential moderators. The cumulative results of 81 effects gathered from 18 studies published between 1988 and 2015 indicated that the magnitude of improvement in 1RM following periodized resistance training was greater than non-periodized resistance training (ES = 0.43, 95% CI 0.27-0.58; P training status (β = -0.59; P = 0.0305), study length (β = 0.03; P = 0.0067), and training frequency (β = 0.46; P = 0.0123) were associated with a change in 1RM. These results indicate that undulating programs were more favorable for strength gains. Improvements in 1RM were greater among untrained participants. Additionally, higher training frequency and longer study length were associated with larger improvements in 1RM. These results suggest that periodized resistance training plans have a moderate effect on 1RM compared to non-periodized training plans. Variation in training stimuli

A Search for Exoplanets in Short-Period Binary Star Systems

Directory of Open Access Journals (Sweden)

Ronald Kaitchuck

2012-03-01

Full Text Available This paper reports the progress of a search for exoplanets with S-type orbits in short-period binary star systems. The selected targets have stellar orbital periods of just a few days. These systems are eclipsing binaries so that exoplanet transits, if planets exist, will be highly likely. We report the results for seven binary star systems.

A structural, functional, and computational analysis suggests pore flexibility as the base for the poor selectivity of CNG channels.

Science.gov (United States)

Napolitano, Luisa Maria Rosaria; Bisha, Ina; De March, Matteo; Marchesi, Arin; Arcangeletti, Manuel; Demitri, Nicola; Mazzolini, Monica; Rodriguez, Alex; Magistrato, Alessandra; Onesti, Silvia; Laio, Alessandro; Torre, Vincent

2015-07-07

Cyclic nucleotide-gated (CNG) ion channels, despite a significant homology with the highly selective K(+) channels, do not discriminate among monovalent alkali cations and are permeable also to several organic cations. We combined electrophysiology, molecular dynamics (MD) simulations, and X-ray crystallography to demonstrate that the pore of CNG channels is highly flexible. When a CNG mimic is crystallized in the presence of a variety of monovalent cations, including Na(+), Cs(+), and dimethylammonium (DMA(+)), the side chain of Glu66 in the selectivity filter shows multiple conformations and the diameter of the pore changes significantly. MD simulations indicate that Glu66 and the prolines in the outer vestibule undergo large fluctuations, which are modulated by the ionic species and the voltage. This flexibility underlies the coupling between gating and permeation and the poor ionic selectivity of CNG channels.

Interspike Interval Based Filtering of Directional Selective Retinal Ganglion Cells Spike Trains

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Aurel Vasile Martiniuc

2012-01-01

Full Text Available The information regarding visual stimulus is encoded in spike trains at the output of retina by retinal ganglion cells (RGCs. Among these, the directional selective cells (DSRGC are signaling the direction of stimulus motion. DSRGCs' spike trains show accentuated periods of short interspike intervals (ISIs framed by periods of isolated spikes. Here we use two types of visual stimulus, white noise and drifting bars, and show that short ISI spikes of DSRGCs spike trains are more often correlated to their preferred stimulus feature (that is, the direction of stimulus motion and carry more information than longer ISI spikes. Firstly, our results show that correlation between stimulus and recorded neuronal response is best at short ISI spiking activity and decrease as ISI becomes larger. We then used grating bars stimulus and found that as ISI becomes shorter the directional selectivity is better and information rates are higher. Interestingly, for the less encountered type of DSRGC, known as ON-DSRGC, short ISI distribution and information rates revealed consistent differences when compared with the other directional selective cell type, the ON-OFF DSRGC. However, these findings suggest that ISI-based temporal filtering integrates a mechanism for visual information processing at the output of retina toward higher stages within early visual system.

The influence of training on the attentional blink and psychological refractory period.

Science.gov (United States)

Garner, K G; Tombu, M N; Dux, P E

2014-05-01

A growing body of research suggests that dual-task interference in sensory consolidation (e.g., the attentional blink, AB) and response selection (e.g., the psychological refractory period, PRP) stems from a common central bottleneck of information processing. With regard to response selection, it is well known that training reduces dual-task interference. We tested whether training that is known to be effective for response selection can also reduce dual-task interference in sensory consolidation. Over two experiments, performance on a PRP paradigm (Exp. 1) and on AB paradigms (differing in their stimuli and task demands, Exps. 1 and 2) was examined after participants had completed a relevant training regimen (T1 practice for both paradigms), an irrelevant training regimen (comparable sensorimotor training, not related to T1 for both tasks), a visual-search training regimen (Exp. 2 only), or after participants had been allocated to a no-training control group. Training that had shown to be effective for reducing dual-task interference in response selection was also found to be effective for reducing interference in sensory consolidation. In addition, we found some evidence that training benefits transferred to the sensory consolidation of untrained stimuli. Collectively, these findings show that training benefits can transfer across cognitive operations that draw on the central bottleneck in information processing. These findings have implications for theories of the AB and for the design of cognitive-training regimens that aim to produce transferable training benefits.

Gully incision rates on the bedrock of a large dip-slope landslide revealed by multi-period LiDAR DEMs

Science.gov (United States)

Chan, Y. C.; Hsieh, Y. C.

2017-12-01

Recent advances in airborne laser scanning (ALS) technology have provided a great opportunity for characterizing surface erosion through developing improved methods in multi-period DEM differencing and geomorphometry. This study uses three periods of ALS digital elevation model (DEM) data to analyze the short-term erosional features of the Tsaoling landslide triggered by the 1999 Chi-Chi earthquake in Taiwan. Two methods for calculating the bedrock incision rate, the equal-interval cross section selection method and the continuous swath profiles selection method, were used in the study after nearly ten years of gully incision following the earthquake-triggered dip-slope landslide. Multi-temporal gully incision rates were obtained using the continuous swath profiles selection method, which is considered a practical and convenient approach in terrain change studies. After error estimation and comparison of the multi-period ALS DEMs, the terrain change in different periods can be directly calculated, reducing time-consuming fieldwork such as installation of erosion pins and measurement of topographic cross sections on site. In this study, the gully bedrock incision rates ranged between 0.23 and 3.98 m/year, remarkably higher than the typical results from the previous studies. By comparing the DEM data, aerial photos, and precipitation records of this area, the effects of erosion could be observed from the retreat of the Chunqiu Cliff outline during August 2011 to September 2012. It was inferred that the change in the topographic elevation during 2011-2012 was mainly due to the torrential rain brought by Typhoon Soula, which occurred on 30 July 2012. The local gully incision rate in the lower part of the landslide surface was remarkably faster than that of the other regions, suggesting that the fast incision of the toe area possibly contributes to the occurrence of repeated landslides in the Tsaoling area.

Global bioevents and the question of periodicity

Science.gov (United States)

Sepkoski, J. John

The hypothesis of periodicity in extinction is an empirical claim that extinction events, while variable in magnitude, are regular in timing and therefore are serially dependent upon some single, ultimate cause with clocklike behavior. This hypothesis is controversal, in part because of questions regarding the identity and timing of certain extinction events and because of speculations concerning possible catastrophic extraterrestrial forcing mechanisms. New data on extinctions of marine animal genera are presented that display a high degree of periodicity in the Mesozoic and Cenozoic as well as a suggestion of nonstationary periodicity in the late Paleozoic. However, no periodicity is evident among the as yet poorly documented extinction events of the early and middle Paleozoic.

Periods found in heat measurements obtained by calorimetry

International Nuclear Information System (INIS)

Jordan, K.C.

1984-01-01

During a span of 640 days, a periodicity of 1.5158 +- 0.0008 days was discovered in successive heater equilibria on Calorimeter No. 127. Measurements were taken at 12-h intervals, with occasional changes of exactly 3 or 6 h in the schedule of measurements. This schedule eliminated all other possible periods except a period of 0.150156 days. Periods of 1.519125 and 1.511283 days were discovered in data on the excess length of day as obtained by the US Naval Observatory over a period of 24 y. These two periods could equally well represent periods of 0.150189 and 0.150112 days, since measurements were obtained only once every 24 h. It is suggested that periods observed in sensitive calorimeters and in length of day data may be related. 1 reference, 6 figures, 5 tables

Colour cues for leaf food selection by long-tailed macaques (Macaca fascicularis) with a new suggestion for the evolution of trichromatic colour vision.

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Lucas, P W; Darvell, B W; Lee, P K; Yuen, T D; Choong, M F

1998-01-01

Leaf colour, size and toughness were investigated in five plant species important in the diet of Macaca fascicularis in Singapore. Leaf colour and size were examined as potential visual cues for food selection, whereas toughness mirrored fibre content, the inverse of food quality. As leaves matured, they changed colour and toughened. Leaf lightness and yellowness were strongly negatively correlated with toughness, but variation in both the red-green axis of the CIE Lab colour space and leaf size were not. Leaves selected as food by the macaques were distinguished by being very light, yellow to slightly green. Some leaves were dappled with red. The literature suggests that these leaves are relatively rich in protein without being tough and therefore would be sought after by primates. We argue that leaf colour is an important indicator of the nutritive value of leaves. Trichromatic vision is an important advantage in finding those palatable leaves that are dappled red. These would appear dark to dichromatic primates and be deceptive by making leaves look older (lower in quality) than they actually are. This would decrease the perceived window of feeding opportunity for such primates who would be at a disadvantage in trying to find these leaves. It is possible that trichromatic vision in catarrhine primates may have originally evolved for the detection of red coloration in the leaves of shade-tolerant tropical plants, enabling the better exploitation of a food resource.

The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors

Energy Technology Data Exchange (ETDEWEB)

Liu, Xueqin [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); School of Social Development and Public Policy, Beijing Normal University, Beijing 100875 (China); Li, Ning [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875 (China); Yuan, Shuai, E-mail: syuan@nmemc.org.cn [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China); Xu, Ning; Shi, Wenqin; Chen, Weibin [National Marine Environmental Monitoring Center, State Oceanic Administration, Dalian 116023 (China)

2015-12-15

As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54 years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10 years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. - Highlights: • A method to estimate the multidimensional joint return periods is presented. • 2D function allows better fitting results at the lower tail of hazard factors. • Three-dimensional simulation has obvious advantages in extreme value fitting. • Joint return periods are closer to the reality

The joint return period analysis of natural disasters based on monitoring and statistical modeling of multidimensional hazard factors

International Nuclear Information System (INIS)

Liu, Xueqin; Li, Ning; Yuan, Shuai; Xu, Ning; Shi, Wenqin; Chen, Weibin

2015-01-01

As a random event, a natural disaster has the complex occurrence mechanism. The comprehensive analysis of multiple hazard factors is important in disaster risk assessment. In order to improve the accuracy of risk analysis and forecasting, the formation mechanism of a disaster should be considered in the analysis and calculation of multi-factors. Based on the consideration of the importance and deficiencies of multivariate analysis of dust storm disasters, 91 severe dust storm disasters in Inner Mongolia from 1990 to 2013 were selected as study cases in the paper. Main hazard factors from 500-hPa atmospheric circulation system, near-surface meteorological system, and underlying surface conditions were selected to simulate and calculate the multidimensional joint return periods. After comparing the simulation results with actual dust storm events in 54 years, we found that the two-dimensional Frank Copula function showed the better fitting results at the lower tail of hazard factors and that three-dimensional Frank Copula function displayed the better fitting results at the middle and upper tails of hazard factors. However, for dust storm disasters with the short return period, three-dimensional joint return period simulation shows no obvious advantage. If the return period is longer than 10 years, it shows significant advantages in extreme value fitting. Therefore, we suggest the multivariate analysis method may be adopted in forecasting and risk analysis of serious disasters with the longer return period, such as earthquake and tsunami. Furthermore, the exploration of this method laid the foundation for the prediction and warning of other nature disasters. - Highlights: • A method to estimate the multidimensional joint return periods is presented. • 2D function allows better fitting results at the lower tail of hazard factors. • Three-dimensional simulation has obvious advantages in extreme value fitting. • Joint return periods are closer to the reality

Open to Suggestion.

Science.gov (United States)

Journal of Reading, 1987

1987-01-01

Offers (1) suggestions for improving college students' study skills; (2) a system for keeping track of parent, teacher, and community contacts; (3) suggestions for motivating students using tic tac toe; (4) suggestions for using etymology to improve word retention; (5) a word search grid; and (6) suggestions for using postcards in remedial reading…

Social and emotional patterns in adulthood: support for socioemotional selectivity theory.

Science.gov (United States)

Carstensen, L L

1992-09-01

This investigation explored 2 hypotheses derived from socioemotional selectivity theory: (a) Selective reductions in social interaction begin in early adulthood and (b) emotional closeness to significant others increases rather than decreases in adulthood even when rate reductions occur. Transcribed interviews with 28 women and 22 men from the Child Guidance Study, conducted over 34 years, were reviewed and rated for frequency of interaction, satisfaction with the relationship, and degree of emotional closeness in 6 types of relationships. Interaction frequency with acquaintances and close friends declined from early adulthood on. Interaction frequency with spouses and siblings increased across the same time period and emotional closeness increased throughout adulthood in relationships with relatives and close friends. Findings suggest that individuals begin narrowing their range of social partners long before old age.

Distinct functions of Period2 and Period3 in the mouse circadian system revealed by in vitro analysis.

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Julie S Pendergast

2010-01-01

Full Text Available The mammalian circadian system, which is composed of a master pacemaker in the suprachiasmatic nuclei (SCN as well as other oscillators in the brain and peripheral tissues, controls daily rhythms of behavior and physiology. Lesions of the SCN abolish circadian rhythms of locomotor activity and transplants of fetal SCN tissue restore rhythmic behavior with the periodicity of the donor's genotype, suggesting that the SCN determines the period of the circadian behavioral rhythm. According to the model of timekeeping in the SCN, the Period (Per genes are important elements of the transcriptional/translational feedback loops that generate the endogenous circadian rhythm. Previous studies have investigated the functions of the Per genes by examining locomotor activity in mice lacking functional PERIOD proteins. Variable behavioral phenotypes were observed depending on the line and genetic background of the mice. In the current study we assessed both wheel-running activity and Per1-promoter-driven luciferase expression (Per1-luc in cultured SCN, pituitary, and lung explants from Per2(-/- and Per3(-/- mice congenic with the C57BL/6J strain. We found that the Per2(-/- phenotype is enhanced in vitro compared to in vivo, such that the period of Per1-luc expression in Per2(-/- SCN explants is 1.5 hours shorter than in Per2+/+ SCN, while the free-running period of wheel-running activity is only 11 minutes shorter in Per2(-/- compared to Per2+/+ mice. In contrast, circadian rhythms in SCN explants from Per3(-/- mice do not differ from Per3+/+ mice. Instead, the period and phase of Per1-luc expression are significantly altered in Per3(-/- pituitary and lung explants compared to Per3+/+ mice. Taken together these data suggest that the function of each Per gene may differ between tissues. Per2 appears to be important for period determination in the SCN, while Per3 participates in timekeeping in the pituitary and lung.

Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting.

Science.gov (United States)

O'Dea, Aaron; Shaffer, Marian Lynne; Doughty, Douglas R; Wake, Thomas A; Rodriguez, Felix A

2014-05-07

Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible.

On the periodicity in the distribution of quasar redshifts

International Nuclear Information System (INIS)

Kjaergaard, P.

1978-01-01

The periodicity in the distribution of quasar redshifts is explained in terms of selection effects. Special attention is drawn to a selection effect caused by the redshift dependent influence of the strong emission lines on the limiting magnitude for detecting quasars. This is especially important since the number of quasars increases with a large factor per magnitude. The limiting magnitude effect applies both to spectroscopic and to UV-excess surveys. It is shown that the redshift distribution of quasars selected by a combination of UV-excess information and agreement between radio and optical position is intermediate between the redshift distribution of the two groups of quasars selected by one of the two criteria. It is also shown that the distribution of redshifts for UV-excess selected quasars is very similar to the variation of the ultrsviolet excess as a function of redshift. This evidence indicates that strong selection effects are in play. (Auth.)

A spatio-temporal synchronization of periodic markets: Evidence ...

African Journals Online (AJOL)

This study seeks to identify the 'rings' of periodic market days in Akwa Ibom State, using eighteen ... numbers was used in selecting a target population of eighteen communities in the hinterland of the state. ... The rural/traditional markets deal on low order goods and are mainly agricultural ... AJOL African Journals Online.

Factor structure of suggestibility revisited: new evidence for direct and indirect suggestibility

Directory of Open Access Journals (Sweden)

Romuald Polczyk

2016-05-01

Full Text Available Background Yielding to suggestions can be viewed as a relatively stable individual trait, called suggestibility. It has been long proposed that there are two kinds of suggestible influence, and two kinds of suggestibility corresponding to them: direct and indirect. Direct suggestion involves overt unhidden influence, while indirect suggestion concerns influence that is hidden, and the participant does not know that the suggestibility is being measured. So far however, empirical evidence for the existence of the two factors has been scarce. In the present study, more sophisticated and reliable tools for measuring suggestibility were applied than in the previous research, in the hope that better measurement would reveal the factor structure of suggestibility. Two tests of direct suggestibility were used: the Harvard Group Scale of Hypnotic Susceptibility, Form A, measuring hypnotic susceptibility, and the Barber Suggestibility Scale, measuring non-hypnotic direct imaginative suggestibility. Three tests served to measure indirect suggestibility: the Sensory Suggestibility Scale, measuring indirect suggestibility relating to perception; the Gudjonsson Suggestibility Scale, measuring the tendency to yield to suggestive questions and changing answers after negative feedback; and the Emotional Dialogs Tests, measuring the tendency to perceive nonexistent aggression. Participants and procedure In sum, 115 participants were tested, 69 women, 49 men, mean age 22.20 years, SD = 2.20. Participants were tested in two sessions, lasting for a total of four hours. Results Confirmatory factor analyses confirmed the existence of two uncorrelated factors of suggestibility: direct and indirect. Conclusions Suggestibility may indeed involve two factors, direct and indirect, and failure to discover them in previous research may be due to methodological problems.

An update on age, hypnotic suggestibility, and gender: a brief report.

Science.gov (United States)

Page, Roger A; Green, Joseph P

2007-04-01

This study assessed the relationship of age and hypnotic suggestibility in an effort to partially update the findings of Morgan and Hilgard (1973). A total of 2,660 undergraduates were administered the Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A; Shor & Orne, 1962) over a 7 year period. Consistent with Morgan and Hilgard's results, we found a general trend for hypnotic suggestibility scores to decrease from age 17 to 40, and then increase thereafter. We also found that female participants scored higher on the HGSHS: A compared with males across the various age ranges that we sampled.

Factor structure of suggestibility revisited: new evidence for direct and indirect suggestibility

OpenAIRE

Romuald Polczyk

2016-01-01

Background Yielding to suggestions can be viewed as a relatively stable individual trait, called suggestibility. It has been long proposed that there are two kinds of suggestible influence, and two kinds of suggestibility corresponding to them: direct and indirect. Direct suggestion involves overt unhidden influence, while indirect suggestion concerns influence that is hidden, and the participant does not know that the suggestibility is being measured. So far however, empirical evidence ...

Changes in cognitive functions of students in the transitional period from elementary school to junior high school.

Science.gov (United States)

Mizuno, Kei; Tanaka, Masaaki; Fukuda, Sanae; Sasabe, Tetsuya; Imai-Matsumura, Kyoko; Watanabe, Yasuyoshi

2011-05-01

When students proceed to junior high school from elementary school, rapid changes in the environment occur, which may cause various behavioral and emotional problems. However, the changes in cognitive functions during this transitional period have rarely been studied. In 158 elementary school students from 4th- to 6th-grades and 159 junior high school students from 7th- to 9th-grades, we assessed various cognitive functions, including motor processing, spatial construction ability, semantic fluency, immediate memory, delayed memory, spatial and non-spatial working memory, and selective, alternative, and divided attention. Our findings showed that performance on spatial and non-spatial working memory, alternative attention, divided attention, and semantic fluency tasks improved from elementary to junior high school. In particular, performance on alternative and divided attention tasks improved during the transitional period from elementary to junior high school. Our finding suggests that development of alternative and divided attention is of crucial importance in the transitional period from elementary to junior high school. Copyright © 2010 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Periodic solutions of nonautonomous differential systems modeling obesity population

International Nuclear Information System (INIS)

Arenas, Abraham J.; Gonzalez-Parra, Gilberto; Jodar, Lucas

2009-01-01

In this paper we study the periodic behaviour of the solutions of a nonautonomous model for obesity population. The mathematical model represented by a nonautonomous system of nonlinear ordinary differential equations is used to model the dynamics of obese populations. Numerical simulations suggest periodic behaviour of subpopulations solutions. Sufficient conditions which guarantee the existence of a periodic positive solution are obtained using a continuation theorem based on coincidence degree theory.

Periodic solutions of nonautonomous differential systems modeling obesity population

Energy Technology Data Exchange (ETDEWEB)

Arenas, Abraham J. [Departamento de Matematicas y Estadistica, Universidad de Cordoba Monteria (Colombia)], E-mail: aarenas@sinu.unicordoba.edu.co; Gonzalez-Parra, Gilberto [Departamento de Calculo, Universidad de los Andes, Merida (Venezuela, Bolivarian Republic of)], E-mail: gcarlos@ula.ve; Jodar, Lucas [Instituto de Matematica Multidisciplinar, Universidad Politecnica de Valencia Edificio 8G, 2o, 46022 Valencia (Spain)], E-mail: ljodar@imm.upv.es

2009-10-30

In this paper we study the periodic behaviour of the solutions of a nonautonomous model for obesity population. The mathematical model represented by a nonautonomous system of nonlinear ordinary differential equations is used to model the dynamics of obese populations. Numerical simulations suggest periodic behaviour of subpopulations solutions. Sufficient conditions which guarantee the existence of a periodic positive solution are obtained using a continuation theorem based on coincidence degree theory.

Oscillatory Mechanisms of Stimulus Processing and Selection in the Visual and Auditory Systems: State-of-the-Art, Speculations and Suggestions

Directory of Open Access Journals (Sweden)

Benedikt Zoefel

2017-05-01

Full Text Available All sensory systems need to continuously prioritize and select incoming stimuli in order to avoid overflow or interference, and provide a structure to the brain's input. However, the characteristics of this input differ across sensory systems; therefore, and as a direct consequence, each sensory system might have developed specialized strategies to cope with the continuous stream of incoming information. Neural oscillations are intimately connected with this selection process, as they can be used by the brain to rhythmically amplify or attenuate input and therefore represent an optimal tool for stimulus selection. In this paper, we focus on oscillatory processes for stimulus selection in the visual and auditory systems. We point out both commonalities and differences between the two systems and develop several hypotheses, inspired by recently published findings: (1 The rhythmic component in its input is crucial for the auditory, but not for the visual system. The alignment between oscillatory phase and rhythmic input (phase entrainment is therefore an integral part of stimulus selection in the auditory system whereas the visual system merely adjusts its phase to upcoming events, without the need for any rhythmic component. (2 When input is unpredictable, the visual system can maintain its oscillatory sampling, whereas the auditory system switches to a different, potentially internally oriented, “mode” of processing that might be characterized by alpha oscillations. (3 Visual alpha can be divided into a faster occipital alpha (10 Hz and a slower frontal alpha (7 Hz that critically depends on attention.

Pedunculated Pulmonary Artery Sarcoma Suggested by Transthoracic Echocardiography.

Science.gov (United States)

Wang, Xiaobing; Ren, Weidong; Yang, Jun

2016-04-01

Pulmonary artery sarcoma (PAS) is an extremely rare malignancy. It is usually found after it grows large enough to occupy almost the entire lumen of the pulmonary artery and causes serious clinical symptoms. Thus, it is usually difficult to distinguish PAS from pulmonary thromboembolism based on imaging examinations. Few case reports had shown the attachment of PAS to pulmonary artery, a key characteristic for diagnosis, and differential diagnosis of PAS. In this case, we found a PAS, which did not cause local obstruction and some tumor emboli, which obstructed the branches of the pulmonary arteries and caused pulmonary hypertension and clinical symptoms. Transthoracic echocardiography (TTE) revealed a part of the tumor attached to the intima of the main pulmonary artery with a peduncle and had obvious mobility, which was suggestive of PAS and differentiated it from the pulmonary thromboembolism. To our knowledge, this is the first case report of a pedunculated PAS suggested by TTE. Combined with pulmonary artery computed tomography angiography, the diagnosis of PAS is strongly suggested before the operation. This case indicates that TTE could reveal the attachment and mobility of PAS in the main pulmonary and may provide useful information for the diagnosis and differential diagnosis of PAS, especially a pedunculated PAS. © 2015, Wiley Periodicals, Inc.

IT Project Selection

DEFF Research Database (Denmark)

Pedersen, Keld

2016-01-01

for initiation. Most of the research on project selection is normative, suggesting new methods, but available empirical studies indicate that many methods are seldom used in practice. This paper addresses the issue by providing increased understanding of IT project selection practice, thereby facilitating...... the development of methods that better fit current practice. The study is based on naturalistic decision-making theory and interviews with experienced project portfolio managers who, when selecting projects, primarily rely on political skills, experience and personal networks rather than on formal IT project......-selection methods, and these findings point to new areas for developing new methodological support for IT project selection....

Selection of Celebrity Endorsers

DEFF Research Database (Denmark)

Hollensen, Svend; Schimmelpfennig, Christian

2013-01-01

several candidates by means of subtle evaluation procedures. Design/methodology/approach – A case study research has been carried out among companies experienced in celebrity endorsements to learn more about the endorser selection process in practise. Based on these cases theory is inductively developed......Purpose - This research aims at shedding some light on the various avenues marketers can undertake until finally an endorsement contract is signed. The focus of the study lies on verifying the generally held assumption that endorser selection is usually taken care of by creative agencies, vetting....... Findings – Our research suggests that generally held assumption that endorsers being selected and thoroughly vetted by a creative agency may not be universally valid. A normative model to illustrate the continuum of the selection process in practise is suggested and the two polar case studies (Swiss brand...

Evaluation of the Use of Periodicals Collection of the Higher Education Council Documentation and Online Search Center: Arts and Humanities Periodicals

Directory of Open Access Journals (Sweden)

Elçin Özbudak

1995-06-01

Full Text Available Evaluation of the use perodicals collections in libraries is important as perodicals report the results of the latest scientific research and they are usually more expensive than other types of library materials. In this study we evaluate the use of Arts and Humanities periodicals in the collection of the Higher Education Council Documentation Center. Although the use of Arts and Humanities periodicals was found to be lower than, say, Biomedical periodicals collection, the number of journal titles in Arts and Humanities appears to be quite satisfactory. Some suggestions are made so as to increase the use of Arts and Humanities periodicals collection.

Calculation of positron characteristics for elements of the periodic table

International Nuclear Information System (INIS)

Campillo Robles, J M; Ogando, E; Plazaola, F

2011-01-01

Positron characteristics have been calculated in bulk and monovacancies for most of the elements of the periodic table. Self-consistent and non-self-consistent schemes have been used for the calculation of the electronic structure in the solid, and different parametrizations for the positron enhancement factor and correlation energy. As it is known, positron lifetimes in bulk show a periodic behaviour with atomic number. These calculations also confirm that monovacancy lifetimes follow the same behaviour. The results obtained have been compared with selected experimental lifetime data, which confirms the calculated theoretical trends. Positron binding energies to a monovacancy have been calculated also for most of the elements of the periodic table. The binding energy shows a periodic behaviour with atomic number too.

Patterns of MHC-DRB1 polymorphism in a post-glacial island canid, the Newfoundland red fox (Vulpes vulpes deletrix), suggest balancing selection at species and population timescales.

Science.gov (United States)

Marshall, H Dawn; Langille, Barbara L; Hann, Crystal A; Whitney, Hugh G

2016-05-01

As the only native insular Newfoundland canid between the extinction of the wolf in the 1930s and the recent arrival of coyotes, the red fox (Vulpes vulpes deletrix Bangs 1898) poses interesting questions about genetic distinctiveness and the post-glacial colonization history of the island's depauperate mammalian fauna. Here, we characterized genetic variability at the major histocompatibility complex (MHC) class II DR β1 domain (DRB1) locus in 28 red foxes from six sampling localities island-wide and compared it with mitochondrial control region (CR) diversity and DRB1 diversity in other canids. Our goals were to describe novel DRB1 alleles in a new canid population and to make inferences about the role of selection in maintaining their diversity. As in numerous studies of vertebrates, we found an order-of-magnitude higher nucleotide diversity at the DRB1 locus compared with the CR and significantly positive nonsynonymous-to-synonymous substitution ratios, indicative of selection in the distant past. Although the evidence is weaker, the Ewens-Watterson test of neutrality and the geographical distribution of variation compared with the CR suggest a role for selection over the evolutionary timescale of populations. We report the first genetic data from the DRB1 locus in the red fox and establish baseline information regarding immunogenetic variation in this island canid population which should inform continued investigations of population demography, adaptive genetic diversity, and wildlife disease in red foxes and related species.

Transit pipelines suggest a tendency to produce conflict and disagreement

International Nuclear Information System (INIS)

Stevens, P.

2009-01-01

Any reading to the history of transit pipeline suggests a tendency to produce conflict and disagreement, often resulting to the cessation of throughput, sometimes for a short period and sometimes for longer. That bad political relation between neighbours have certain a role, but very important is the economic nature of the transit terms, tariff and off take terms. What might be done to improve this record in the future and make transit pipeline less vulnerable and troublesome? [it

The evolution of phenotypic integration: How directional selection reshapes covariation in mice.

Science.gov (United States)

Penna, Anna; Melo, Diogo; Bernardi, Sandra; Oyarzabal, Maria Inés; Marroig, Gabriel

2017-10-01

Variation is the basis for evolution, and understanding how variation can evolve is a central question in biology. In complex phenotypes, covariation plays an even more important role, as genetic associations between traits can bias and alter evolutionary change. Covariation can be shaped by complex interactions between loci, and this genetic architecture can also change during evolution. In this article, we analyzed mouse lines experimentally selected for changes in size to address the question of how multivariate covariation changes under directional selection, as well as to identify the consequences of these changes to evolution. Selected lines showed a clear restructuring of covariation in their cranium and, instead of depleting their size variation, these lines increased their magnitude of integration and the proportion of variation associated with the direction of selection. This result is compatible with recent theoretical works on the evolution of covariation that take the complexities of genetic architecture into account. This result also contradicts the traditional view of the effects of selection on available covariation and suggests a much more complex view of how populations respond to selection. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Strategic Vision: A Selected Bibliography

National Research Council Canada - National Science Library

Moyer, Jeannette

2008-01-01

Strategic Vision is an enduring theme at the U.S. Army War College. Compiled in support of this theme, this selected bibliography reflects books, documents, periodical articles, and a number of web sites...

Multi-Period Portfolio Optimization of Power Generation Assets

Directory of Open Access Journals (Sweden)

Barbara Glensk

2013-01-01

Full Text Available The liberalization and deregulation of the energy industry in the past decades have been significantly affected by changes in the strategies of energy firms. The traditionally used approach of cost minimization was no longer sufficient, risk and market behavior could no longer be ignored and the need for more appropriate optimization methods for uncertain environments was increased. Meanvariance portfolio (MVP theory is one of the more advanced financial methods that has been successfully applied to the energy sector. Unfortunately, this static approach is inadequate for studying multi-stage investment decision problems. The methodology proposed in this paper considering power generation assets is based on the model introduced by Mulvey, who suggests a reallocation approach using the analysis of various scenarios. The adoption of this methodology to power generation assets allows us to capture the impact of variations in the economic and technical parameters considered. The results of our study show that the application of a model for selection of multi-period portfolio can indeed improve the decision making process. Especially for the case of adding new investments to the portfolio mix, this rebalancing model captures new entries very well. (original abstract

Bomb survivor selection and consequences for estimates of population cancer risks

International Nuclear Information System (INIS)

Little, M.P.; Charles, M.W.

1990-01-01

Health records of the Japanese bomb survivor population [with the 1965 (T65D) and 1986 (DS86) dosimetry systems] have been analyzed and some evidence found for the selection effect hypothesized by Stewart and Kneale. This is found to be significant in only the first of the periods examined (1950-1958), and the effect diminishes in magnitude thereafter. There are indications that the effect might be an artifact of the T65D dosimetry, in which it is observed more strongly than in the DS86 data. There is no evidence to suggest that selection on this basis might confer correspondingly reduced susceptibility to radiation-induced cancer. If, however, one makes this assumption, as suggested by Stewart and Kneale, then current estimates of population cancer risks might need to be inflated by between 5% and 35% (for excess cancer deaths, Gy-1) or between 8% and 40% (for years of life lost, Gy-1) to account for this. It is likely that these figures, even assuming them not to be simply an artifact of the T65D dosimetry, overestimate the degree of adjustment required to the risk estimates

Quantum model for a periodically driven selectivity filter in a K+ ion channel

International Nuclear Information System (INIS)

Cifuentes, A A; Semião, F L

2014-01-01

In this work, we present a quantum transport model for the selectivity filter in the KcsA potassium ion channel. This model is fully consistent with the fact that two conduction pathways are involved in the translocation of ions through the filter, and we show that the presence of a second path may actually bring advantages for the filter as a result of quantum interference. To highlight interferences and resonances in the model, we consider the selectivity filter to be driven by a controlled time-dependent external field, which changes the free-energy scenario and consequently the conduction of the ions. In particular, we demonstrate that the two-pathway conduction mechanism is more advantageous for the filter when dephasing in the transient configurations is lower than in the main configurations. As a matter of fact, K + ions in the main configurations are highly coordinated by oxygen atoms of the filter backbone, and this increases noise. Moreover, we also show that for a wide range of dephasing rates and driving frequencies, the two-pathway conduction used by the filter leads to higher ionic currents than the single–path model. (paper)

Natural selection against a circadian clock gene mutation in mice.

Science.gov (United States)

Spoelstra, Kamiel; Wikelski, Martin; Daan, Serge; Loudon, Andrew S I; Hau, Michaela

2016-01-19

Circadian rhythms with an endogenous period close to or equal to the natural light-dark cycle are considered evolutionarily adaptive ("circadian resonance hypothesis"). Despite remarkable insight into the molecular mechanisms driving circadian cycles, this hypothesis has not been tested under natural conditions for any eukaryotic organism. We tested this hypothesis in mice bearing a short-period mutation in the enzyme casein kinase 1ε (tau mutation), which accelerates free-running circadian cycles. We compared daily activity (feeding) rhythms, survivorship, and reproduction in six replicate populations in outdoor experimental enclosures, established with wild-type, heterozygous, and homozygous mice in a Mendelian ratio. In the release cohort, survival was reduced in the homozygote mutant mice, revealing strong selection against short-period genotypes. Over the course of 14 mo, the relative frequency of the tau allele dropped from initial parity to 20%. Adult survival and recruitment of juveniles into the population contributed approximately equally to the selection for wild-type alleles. The expression of activity during daytime varied throughout the experiment and was significantly increased by the tau mutation. The strong selection against the short-period tau allele observed here contrasts with earlier studies showing absence of selection against a Period 2 (Per2) mutation, which disrupts internal clock function, but does not change period length. These findings are consistent with, and predicted by the theory that resonance of the circadian system plays an important role in individual fitness.

A New Spectral Shape-Based Record Selection Approach Using Np and Genetic Algorithms

Directory of Open Access Journals (Sweden)

Edén Bojórquez

2013-01-01

Full Text Available With the aim to improve code-based real records selection criteria, an approach inspired in a parameter proxy of spectral shape, named Np, is analyzed. The procedure is based on several objectives aimed to minimize the record-to-record variability of the ground motions selected for seismic structural assessment. In order to select the best ground motion set of records to be used as an input for nonlinear dynamic analysis, an optimization approach is applied using genetic algorithms focuse on finding the set of records more compatible with a target spectrum and target Np values. The results of the new Np-based approach suggest that the real accelerograms obtained with this procedure, reduce the scatter of the response spectra as compared with the traditional approach; furthermore, the mean spectrum of the set of records is very similar to the target seismic design spectrum in the range of interest periods, and at the same time, similar Np values are obtained for the selected records and the target spectrum.

Late emergence of the vibrissa direction selectivity map in the rat barrel cortex.

Science.gov (United States)

Kremer, Yves; Léger, Jean-François; Goodman, Dan; Brette, Romain; Bourdieu, Laurent

2011-07-20

In the neocortex, neuronal selectivities for multiple sensorimotor modalities are often distributed in topographical maps thought to emerge during a restricted period in early postnatal development. Rodent barrel cortex contains a somatotopic map for vibrissa identity, but the existence of maps representing other tactile features has not been clearly demonstrated. We addressed the issue of the existence in the rat cortex of an intrabarrel map for vibrissa movement direction using in vivo two-photon imaging. We discovered that the emergence of a direction map in rat barrel cortex occurs long after all known critical periods in the somatosensory system. This map is remarkably specific, taking a pinwheel-like form centered near the barrel center and aligned to the barrel cortex somatotopy. We suggest that this map may arise from intracortical mechanisms and demonstrate by simulation that the combination of spike-timing-dependent plasticity at synapses between layer 4 and layer 2/3 and realistic pad stimulation is sufficient to produce such a map. Its late emergence long after other classical maps suggests that experience-dependent map formation and refinement continue throughout adult life.

Motivated encoding selectively promotes memory for future inconsequential semantically-related events.

Science.gov (United States)

Oyarzún, Javiera P; Packard, Pau A; de Diego-Balaguer, Ruth; Fuentemilla, Lluis

2016-09-01

Neurobiological models of long-term memory explain how memory for inconsequential events fades, unless these happen before or after other relevant (i.e., rewarding or aversive) or novel events. Recently, it has been shown in humans that retrospective and prospective memories are selectively enhanced if semantically related events are paired with aversive stimuli. However, it remains unclear whether motivating stimuli, as opposed to aversive, have the same effect in humans. Here, participants performed a three phase incidental encoding task where one semantic category was rewarded during the second phase. A memory test 24h after, but not immediately after encoding, revealed that memory for inconsequential items was selectively enhanced only if items from the same category had been previously, but not subsequently, paired with rewards. This result suggests that prospective memory enhancement of reward-related information requires, like previously reported for aversive memories, of a period of memory consolidation. The current findings provide the first empirical evidence in humans that the effects of motivated encoding are selectively and prospectively prolonged over time. Copyright © 2016 Elsevier Inc. All rights reserved.

Influence of ERβ selective agonism during the neonatal period on the sexual differentiation of the rat hypothalamic-pituitary-gonadal (HPG axis

Directory of Open Access Journals (Sweden)

Patisaul Heather B

2012-01-01

Full Text Available Abstract Background It is well established that sexual differentiation of the rodent hypothalamic-pituitary-gonadal (HPG axis is principally orchestrated by estrogen during the perinatal period. Here we sought to better characterize the mechanistic role the beta form of the estrogen receptor (ERβ plays in this process. Methods To achieve this, we exposed neonatal female rats to three doses (0.5, 1 and 2 mg/kg of the ERβ selective agonist diarylpropionitrile (DPN using estradiol benzoate (EB as a positive control. Measures included day of vaginal opening, estrous cycle quality, GnRH and Fos co-localization following ovariectomy and hormone priming, circulating luteinizing hormone (LH levels and quantification of hypothalamic kisspeptin immunoreactivity. A second set of females was then neonatally exposed to DPN, the ERα agonist propyl-pyrazole-triol (PPT, DPN+PPT, or EB to compare the impact of ERα and ERβ selective agonism on kisspeptin gene expression in pre- and post-pubescent females. Results All three DPN doses significantly advanced the day of vaginal opening and induced premature anestrus. GnRH and Fos co-labeling, a marker of GnRH activation, following ovariectomy and hormone priming was reduced by approximately half at all doses; the magnitude of which was not as large as with EB or what we have previously observed with the ERα agonist PPT. LH levels were also correspondingly lower, compared to control females. No impact of DPN was observed on the density of kisspeptin immunoreactive (-ir fibers or cell bodies in the arcuate (ARC nucleus, and kisspeptin-ir was only significantly reduced by the middle (1 mg/kg DPN dose in the preoptic region. The second experiment revealed that EB, PPT and the combination of DPN+PPT significantly abrogated preoptic Kiss1 expression at both ages but ARC expression was only reduced by EB. Conclusion Our results indicate that selective agonism of ERβ is not sufficient to completely achieve male

Selective Serotonin Reuptake Inhibitors for Treatment of Selective Mutism

Directory of Open Access Journals (Sweden)

Mazlum Çöpür

2012-03-01

Full Text Available Some authors suggest that selective mutism should be considered as a variant of social phobia or a disorder in the obsessive-compulsive spectrum. Recent studies indicate that pharmacological treatments may be effective in the treatment of selective mutism. In this article, four cases who were treated with citalopram and escitalopram are presented. The results indicate that the drugs were well tolerated, and the level of social and verbal interactions improved significantly. These findings have shown that citalopram and escitalopram can be considered in medication of selective mutism; nevertheless, it is essential that research be done with more cases than previous ones, in order to prove their accuracy

Gastric and renal effects of COX-2 selective and non-selective NSAIDs in rats receiving low-dose aspirin therapy

Directory of Open Access Journals (Sweden)

Marcella Goetz MORO

Full Text Available Abstract The consumption of low-dose aspirin (LDA to prevent cardiovascular disease continues to increase worldwide. Consequently, the number of chronic LDA users seeking dental procedures that require complementary acute anti-inflammatory medication has also grown. Considering the lack of literature evaluating this interaction, we analyzed the gastric and renal effects caused by a selective COX-2 inhibitor (etoricoxib and a non-selective COX-2 inhibitor (ibuprofen nonsteroidal anti-inflammatory drug (NSAID in rats receiving chronic LDA therapy. Male Wistar rats were divided into six experimental groups (carboxymethylcellulose (CMC - vehicle; LDA; LDA + ibuprofen; ibuprofen; LDA + etoricoxib; and etoricoxib and submitted to long-term LDA therapy with a subsequent NSAID administration for three days by gavage. After the experimental period, we analyzed gastric and renal tissues and quantified serum creatinine levels. The concomitant use of LDA with either NSAID induced the highest levels of gastric damage when compared to the CMC group (F = 20.26, p 0.05. These results suggest that even the acute use of an NSAID (regardless of COX-2 selectivity can induce gastric damage when combined with the long-term use of low-dose aspirin in an animal model. Additional studies, including clinical assessments, are thus needed to clarify this interaction, and clinicians should be careful of prescribing NSAIDs to patients using LDA.

Forest Succession and Maternity Day roost selection by Myotis septentrionalis in a mesophytic hardwood forest

Science.gov (United States)

Silvis, Alexander; Ford, W. Mark; Eric R. Britzke,; Nathan R. Beane,; Joshua B. Johnson,

2012-01-01

Conservation of summer maternity roosts is considered critical for bat management in North America, yet many aspects of the physical and environmental factors that drive roost selection are poorly understood. We tracked 58 female northern bats (Myotis septentrionalis) to 105 roost trees of 21 species on the Fort Knox military reservation in north-central Kentucky during the summer of 2011. Sassafras (Sassafras albidum) was used as a day roost more than expected based on forest stand-level availability and accounted for 48.6% of all observed day roosts. Using logistic regression and an information theoretic approach, we were unable to reliably differentiate between sassafras and other roost species or between day roosts used during different maternity periods using models representative of individual tree metrics, site metrics, topographic location, or combinations of these factors. For northern bats, we suggest that day-roost selection is not a function of differences between individual tree species per se, but rather of forest successional patterns, stand and tree structure. Present successional trajectories may not provide this particular selected structure again without management intervention, thereby suggesting that resource managers take a relatively long retrospective view to manage current and future forest conditions for bats.

Predicting rates of inbreeding in populations undergoing selection

NARCIS (Netherlands)

Woolliams, J.A.; Bijma, P.

2000-01-01

Tractable forms of predicting rates of inbreeding (F) in selected populations with general indices, nonrandom mating, and overlapping generations were developed, with the principal results assuming a period of equilibrium in the selection process. An existing theorem concerning the relationship

Factors of site selection for nuclear power plants in selected industrial states

International Nuclear Information System (INIS)

Hoffmann, L.; Obermair, G.; Ringler, W.; Romahn, B.; Sanders, H.

1978-01-01

The range of the tasks within the project consists of working out an optimal catalogue of criteria for the site selection for nuclear power plants; establishing a structured documentation system for the criteria and licensing procedures used by selected industrial countries when selecting sites for nuclear power plants; analyzing and evaluating the documented material with the aim of supplying the basis for decisions concerning land use. The tasks are being realized within a technological ring of data (for the period until 1990, reactor types, cooling, power-heat coupling, special sites, block sizes, local concentration) and a set politico-economical ring of data for the following countries: F.R. Germany, Belgium, Switzerland, Great Britain, Sweden, Denmark, Austria, France, Netherlands, USA, Japan, Yougoslavia. (HP) [de

Dietary selection by steers grazing kikuyu

African Journals Online (AJOL)

being grazeA for a period of 3,5 days in a four-week rotation, at ... Cattle improve the quality of their diet by actively seeking ... of stem in their diet. This would explain why the stem fraction mad~ no significant contribution to the equation predicting diet~ry selection. A:1unusual fact which emerged is that the animals selected.

Treatment of selective mutism: focus on selective serotonin reuptake inhibitors.

Science.gov (United States)

Kaakeh, Yaman; Stumpf, Janice L

2008-02-01

Abstract Selective mutism is a pediatric psychiatric disorder that occurs when a child consistently fails to speak in specific situations in which speaking is expected, such as at school and social gatherings, but speaks appropriately in other settings. Selective mutism often is diagnosed when a child starts school and does not talk to teachers or peers, but talks to family members at home; the condition is frequently accompanied by anxiety and shyness. Although the underlying etiology of the condition remains unclear, psychotherapy is the preferred initial treatment, with the support of parents and teachers. If the child does not respond to psychotherapy, addition of pharmacologic treatment should be considered, depending on the severity of symptoms and presence of other illnesses. Although data are limited to case reports and trials with small patient populations and short follow-up periods, some patients with selective mutism respond to therapy with selective serotonin reuptake inhibitors (SSRIs). Fluoxetine is the most studied SSRI as treatment for the condition, although further investigation is required to determine the optimal dosage and duration of therapy.

Hearths in the coastal areas of northernmost Sweden, from the period AD 800 to 1950

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Lars Liedgren

2016-08-01

Full Text Available This paper presents a study of the chronological setting of hearths registered in FMIS (digital register containing records of all known ancient monuments in Sweden in the provinces of Västerbotten and Norrbotten, Northern Sweden. A total of c. 1500 hearths are known in the area, mainly situated north of the river Skellefteälven. Within a study area of 107 x 94 km, 32 hearths were randomly selected for excavation, each site embracing 1-14 hearths. The sites were scanned using a metal detector and nearly all artifacts found were from the period AD 1600-1900. 14C-datings of charcoal and burned bones corroborated that most hearths were used during this period, with a large number dating to the 19th and 20th centuries. Many hearths contained bones from mature reindeer, indicating that the hearths were related to reindeer herding. We suggest that most hearths are related to nomadic Sami reindeer herders using coastal areas for winter pasture, possibly resulting from the breakdown of the “lappskatteland” (taxation lands system and an increase in reindeer numbers.

Acute Phase Proteins and Variables of Protein Metabolism in Dairy Cows during the Pre- and Postpartal Period

Directory of Open Access Journals (Sweden)

Cs. Tóthová

2008-01-01

Full Text Available The objective of the present study was to compare the concentrations of acute phase proteins and selected variables of protein metabolism in dairy cows of the Slovak Spotted breed from 4 weeks before parturition to 10 weeks after parturition. Acute phase proteins - haptoglobin (Hp and serum amyloid A (SAA - and variables of protein metabolism - total proteins, albumin, urea, creatinine, total immunoglobulins - were evaluated in blood serum. Significant differences were found in average values of the Hp and SAA concentrations in several groups during the monitored period (P P P P P P P P P < 0.001. The above mentioned results indicate that in the time around parturition there are significant changes in concentrations of acute phase proteins, as well as in the whole protein metabolism of dairy cows. These facts suggest that the postparturient period is a critical biological phase, throughout which there is the highest incidence of metabolic disorders.

Spatial and temporal variation in selection of genes associated with pearl millet varietal quantitative traits in situ

Directory of Open Access Journals (Sweden)

Cedric Mariac

2016-07-01

Full Text Available Ongoing global climate changes imply new challenges for agriculture. Whether plants and crops can adapt to such rapid changes is still a widely debated question. We previously showed adaptation in the form of earlier flowering in pearl millet at the scale of a whole country over three decades. However, this analysis did not deal with variability of year to year selection. To understand and possibly manage plant and crop adaptation, we need more knowledge of how selection acts in situ. Is selection gradual, abrupt, and does it vary in space and over time? In the present study, we tracked the evolution of allele frequency in two genes associated with pearl millet phenotypic variation in situ. We sampled 17 populations of cultivated pearl millet over a period of two years. We tracked changes in allele frequencies in these populations by genotyping more than seven thousand individuals. We demonstrate that several allele frequencies changes are compatible with selection, by correcting allele frequency changes associated with genetic drift. We found marked variation in allele frequencies from year to year, suggesting a variable selection effect in space and over time. We estimated the strength of selection associated with variations in allele frequency. Our results suggest that the polymorphism maintained at the genes we studied is partially explained by the spatial and temporal variability of selection. In response to environmental changes, traditional pearl millet varieties could rapidly adapt thanks to this available functional variability.

SCHOOL LUNCH, SUGGESTED GUIDES FOR SELECTING LARGE EQUIPMENT.

Science.gov (United States)

South Carolina State Dept. of Education, Columbia.

THE TYPE AND CAPACITY OF A WIDE RANGE OF SCHOOL KITCHEN EQUIPMENT IS RECOMMENDED WITH RESPECT TO THE NUMBER OF MEALS SERVED PER DAY. THESE RECOMMENDATIONS ARE GIVEN FOR RANGES, SINKS, ELECTRIC HEATING, GAS HEATING, REFRIGERATION, TABLES, KITCHEN MACHINES, TRUCK DOLLIES, SCALES, STORAGE CABINETS, OFFICE SPACES, LOUNGES, GARBAGE AND CAN WASHING…

Affective changes during the postpartum period: Influences of genetic and experiential factors.

Science.gov (United States)

Agrati, Daniella; Lonstein, Joseph S

2016-01-01

This article is part of a Special Issue "Parental Care". The postpartum period involves some truly transformational changes in females' socioemotional behaviors. For most female laboratory rodents and women, these changes include an improvement in their affective state, which has positive consequences for their ability to sensitively care for their offspring. There is heterogeneity among females in the likelihood of this positive affective change, though, and some women experience elevated anxiety or depression (or in rodents anxiety- or depression-related behaviors) after giving birth. We aim to contribute to the understanding of this heterogeneity in maternal affectivity by reviewing selected components of the scientific literatures on laboratory rodents and humans examining how mothers' physical contact with her infants, genetics, history of anxiety and depression and early-life and recent-life experiences contribute to individual differences in postpartum affective states. These studies together indicate that multiple biological and environmental factors beyond female maternal state shape affective responses during the postpartum period, and probably do so in an interactive manner. Furthermore, the similar capacity of some of these factors to modulate anxiety and depression in human and rodent mothers suggests cross-species conservation of mechanisms regulating postpartum affectivity. Copyright © 2015 Elsevier Inc. All rights reserved.

Responding to hypnotic and nonhypnotic suggestions: performance standards, imaginative suggestibility, and response expectancies.

Science.gov (United States)

Meyer, Eric C; Lynn, Steven Jay

2011-07-01

This study examined the relative impact of hypnotic inductions and several other variables on hypnotic and nonhypnotic responsiveness to imaginative suggestions. The authors examined how imaginative suggestibility, response expectancies, motivation to respond to suggestions, and hypnotist-induced performance standards affected participants' responses to both hypnotic and nonhypnotic suggestions and their suggestion-related experiences. Suggestions were administered to 5 groups of participants using a test-retest design: (a) stringent performance standards; (b) lenient performance standards; (c) hypnosis test-retest; (d) no-hypnosis test-retest; and (e) no-hypnosis/hypnosis control. The authors found no support for the influence of a hypnotic induction or performance standards on responding to suggestions but found considerable support for the role of imaginative suggestibility and response expectancies in predicting responses to both hypnotic and nonhypnotic suggestions.

THE ROTATION PERIOD OF HD-77581 (VELA X-1)

NARCIS (Netherlands)

ZUIDERWIJK, EJ

The rotation period of HD 77581, supergiant primary in the X-ray binary Vela X-1, is determined from an analysis of selected absorption line profiles. The rotation rate determined from He I line profiles is 0.67 +/- 0.04 times that of the binary angular velocity, corresponding to a rotation velocity

Natural selection and sex differences in morbidity and mortality in early life.

Science.gov (United States)

Wells, J C

2000-01-07

Both morbidity and mortality are consistently reported to be higher in males than in females in early life, but no explanation for these findings has been offered. This paper argues that the sex difference in early vulnerability can be attributed to the natural selection of optimal maternal strategies for maximizing lifetime reproductive success, as modelled previously by Trivers and Willard. These authors theorized that males and females offer different returns on parental investment depending on the state of the environment. Natural selection has therefore favoured maternal ability to manipulate offspring sex in response to environmental conditions in early life, as shown in variation in the sex ratio at birth. This argument can be extended to the whole period of parental investment until weaning. Male vulnerability in response to environmental stress in early life is predicted to have been favoured by natural selection. This vulnerability is most evident in the harsh conditions resulting from pre-term birth, but can also be seen in term infants, and manifests as greater morbidity and mortality persisting into early childhood. Malnutrition, interacting with infection after birth, is suggested as the fundamental trigger mechanism. The model suggests that whatever improvements are made in medical care, any environmental stress will always affect males more severely than females in early life. Copyright 2000 Academic Press.

[Hypertension and pregnancy: Post-partum period].

Science.gov (United States)

Hugon-Rodin, Justine; Plu-Bureau, Geneviève

2016-01-01

Post-partum period is associated with specific characteristics in women with gestational disorders or preeclampsia. For breastfeeding women, the choice of antihypertensive treatment should take into account the impact on child health. The impact of breastfeeding on health mother must be also discussed. Moreover, for lactation inhibition, bromocriptine should not be used, especially in the context of gestational disorders. In post-partum period, the best contraceptive strategy is only-progestin contraception or non-hormonal contraceptives use. However, this choice will depend on the stabilization or normalization of blood pressure in early post-partum period. Finally, several consultations should be suggested: an information and announcement to explain the consequences of these gestational disorders and organize their multidisciplinary management and follow-up. A preconceptional consultation takes its place to anticipate potential recurrent preeclampsia or gestational hypertension and to schedule a future pregnancy in optimal conditions. Copyright © 2016. Published by Elsevier Masson SAS.

Suicidality and interrogative suggestibility.

Science.gov (United States)

Pritchard-Boone, Lea; Range, Lillian M

2005-01-01

All people are subject to memory suggestibility, but suicidal individuals may be especially so. The link between suicidality and suggestibility is unclear given mixed findings and methodological weaknesses of past research. To test the link between suicidality and interrogative suggestibility, 149 undergraduates answered questions about suicidal thoughts and reasons for living, and participated in a direct suggestibility procedure. As expected, suggestibility correlated with suicidality but accounted for little overall variance (4%). Mental health professionals might be able to take advantage of client suggestibility by directly telling suicidal persons to refrain from suicidal thoughts or actions.

Evolution of embryonic developmental period in the marine bird families Alcidae and Spheniscidae: roles for nutrition and predation?

Science.gov (United States)

Hipfner, J Mark; Gorman, Kristen B; Vos, Rutger A; Joy, Jeffrey B

2010-06-14

Nutrition and predation have been considered two primary agents of selection important in the evolution of avian life history traits. The relative importance of these natural selective forces in the evolution of avian embryonic developmental period (EDP) remain poorly resolved, perhaps in part because research has tended to focus on a single, high taxonomic-level group of birds: Order Passeriformes. The marine bird families Alcidae (auks) and Spheniscidae (penguins) exhibit marked variation in EDP, as well as behavioural and ecological traits ultimately linked to EDP. Therefore, auks and penguins provide a unique opportunity to assess the natural selective basis of variation in a key life-history trait at a low taxonomic-level. We used phylogenetic comparative methods to investigate the relative importance of behavioural and ecological factors related to nutrition and predation in the evolution of avian EDP. Three behavioural and ecological variables related to nutrition and predation risk (i.e., clutch size, activity pattern, and nesting habits) were significant predictors of residual variation in auk and penguin EDP based on models predicting EDP from egg mass. Species with larger clutch sizes, diurnal activity patterns, and open nests had significantly shorter EDPs. Further, EDP was found to be longer among birds which forage in distant offshore waters, relative to those that foraged in near shore waters, in line with our predictions, but not significantly so. Current debate has emphasized predation as the primary agent of selection driving avian life history diversification. Our results suggest that both nutrition and predation have been important selective forces in the evolution of auk and penguin EDP, and highlight the importance of considering these questions at lower taxonomic scales. We suggest that further comparative studies on lower taxonomic-level groups will continue to constructively inform the debate on evolutionary determinants of avian EDP, as

Analysis of irradiation processes for laser-induced periodic surface structures

NARCIS (Netherlands)

Eichstädt, J.; Huis In 't Veld, A.J.

2013-01-01

The influence of errors on the irradiation process for laser-induced periodic surface structures (LIPSS) was studied theoretically with energy density simulations. Therefore an irradiation model has been extended by a selection of technical variations. The influence of errors has been found in a

Live imaging-based model selection reveals periodic regulation of the stochastic G1/S phase transition in vertebrate axial development.

Directory of Open Access Journals (Sweden)

Mayu Sugiyama

2014-12-01

Full Text Available In multicellular organism development, a stochastic cellular response is observed, even when a population of cells is exposed to the same environmental conditions. Retrieving the spatiotemporal regulatory mode hidden in the heterogeneous cellular behavior is a challenging task. The G1/S transition observed in cell cycle progression is a highly stochastic process. By taking advantage of a fluorescence cell cycle indicator, Fucci technology, we aimed to unveil a hidden regulatory mode of cell cycle progression in developing zebrafish. Fluorescence live imaging of Cecyil, a zebrafish line genetically expressing Fucci, demonstrated that newly formed notochordal cells from the posterior tip of the embryonic mesoderm exhibited the red (G1 fluorescence signal in the developing notochord. Prior to their initial vacuolation, these cells showed a fluorescence color switch from red to green, indicating G1/S transitions. This G1/S transition did not occur in a synchronous manner, but rather exhibited a stochastic process, since a mixed population of red and green cells was always inserted between newly formed red (G1 notochordal cells and vacuolating green cells. We termed this mixed population of notochordal cells, the G1/S transition window. We first performed quantitative analyses of live imaging data and a numerical estimation of the probability of the G1/S transition, which demonstrated the existence of a posteriorly traveling regulatory wave of the G1/S transition window. To obtain a better understanding of this regulatory mode, we constructed a mathematical model and performed a model selection by comparing the results obtained from the models with those from the experimental data. Our analyses demonstrated that the stochastic G1/S transition window in the notochord travels posteriorly in a periodic fashion, with doubled the periodicity of the neighboring paraxial mesoderm segmentation. This approach may have implications for the characterization of

Ultra-short period X-ray mirrors: Production and investigation

International Nuclear Information System (INIS)

Bibishkin, M.S.; Chkhalo, N.I.; Fraerman, A.A.; Pestov, A.E.; Prokhorov, K.A.; Salashchenko, N.N.; Vainer, Yu.A.

2005-01-01

Technological problems that deal with manufacturing of highly effective ultra-short (d=0.7-3.2 nm) period X-ray multilayer mirrors (MLM) are discussed in the article. In an example of Cr/Sc and W/B 4 C MLM it is experimentally shown, that the problem of periodicity and selectivity for multilayer dispersive X-ray elements has been generally solved by now. However, the problem of short-period MLM reflectivity increase related to existing of transitive borders between layers in structures remains rather urgent. The new technique of tungsten deposition using the RF source in order to decrease roughness in borders is discussed and tested. The results of measurements on wavelengths of 0.154, 0.834 and 1.759 nm are given. The RbAP crystals ordinary used in experiments and short-period W/B 4 C MLM produced are compared. The specular and non-specular characteristics of scattering on the 0.154 nm wavelengths are also measured in order to study transitive borders structures

Molecular epidemiology and evolution of avian infectious bronchitis virus in Spain over a fourteen-year period.

Science.gov (United States)

Dolz, Roser; Pujols, Joan; Ordóñez, German; Porta, Ramon; Majó, Natàlia

2008-04-25

An in-depth molecular study of infectious bronchitis viruses (IBV) with particular interest in evolutionary aspects of IBV in Spain was carried out in the present study based on the S1 gene molecular characterization of twenty-six Spanish strains isolated over a fourteen-year period. Four genotypes were identified based on S1 gene sequence analyses and phylogenetic studies. A drastic virus population shift was demonstrated along time and the novel Italy 02 serotype was shown to have displaced the previous predominant serotype 4/91 in the field. Detailed analyses of synonymous to non-synonymous ratio of the S1 gene sequences of this new serotype Italy 02 suggested positive selection pressures might have contributed to the successful establishment of Italy 02 serotype in our country. In addition, differences on the fitness abilities of new emergent genotypes were indicated. Furthermore, intergenic sequences (IGs)-like motifs within S1 gene sequences of IBV isolates were suggested to enhance the recombination abilities of certain serotypes.

Anesthetics rapidly promote synaptogenesis during a critical period of brain development.

Directory of Open Access Journals (Sweden)

Mathias De Roo

Full Text Available Experience-driven activity plays an essential role in the development of brain circuitry during critical periods of early postnatal life, a process that depends upon a dynamic balance between excitatory and inhibitory signals. Since general anesthetics are powerful pharmacological modulators of neuronal activity, an important question is whether and how these drugs can affect the development of synaptic networks. To address this issue, we examined here the impact of anesthetics on synapse growth and dynamics. We show that exposure of young rodents to anesthetics that either enhance GABAergic inhibition or block NMDA receptors rapidly induce a significant increase in dendritic spine density in the somatosensory cortex and hippocampus. This effect is developmentally regulated; it is transient but lasts for several days and is also reproduced by selective antagonists of excitatory receptors. Analyses of spine dynamics in hippocampal slice cultures reveals that this effect is mediated through an increased rate of protrusions formation, a better stabilization of newly formed spines, and leads to the formation of functional synapses. Altogether, these findings point to anesthesia as an important modulator of spine dynamics in the developing brain and suggest the existence of a homeostatic process regulating spine formation as a function of neural activity. Importantly, they also raise concern about the potential impact of these drugs on human practice, when applied during critical periods of development in infants.

The eclipse period of Escherichia coli

DEFF Research Database (Denmark)

von Freiesleben, Ulrik; Krekling, Martin A.; Hansen, Flemming G.

2000-01-01

corresponds to the period of origin hemimethylation. The SeqA protein was absolutely required for the eclipse, and DnaA titration studies suggested that the SeqA protein prevented the binding of multiple DnaA molecules on oriC (initial complex formation). No correlation between the amount of SeqA and eclipse...... length was revealed, but increased SeqA levels affected chromosome partitioning and/or cell division. This was corroborated further by an aberrant nucleoid distribution in SeqA-deficient cells. We suggest that the SeqA protein's role in maintaining the eclipse is tied to a function in chromosome...

Feature-selective attention in healthy old age: a selective decline in selective attention?

Science.gov (United States)

Quigley, Cliodhna; Müller, Matthias M

2014-02-12

Deficient selection against irrelevant information has been proposed to underlie age-related cognitive decline. We recently reported evidence for maintained early sensory selection when older and younger adults used spatial selective attention to perform a challenging task. Here we explored age-related differences when spatial selection is not possible and feature-selective attention must be deployed. We additionally compared the integrity of feedforward processing by exploiting the well established phenomenon of suppression of visual cortical responses attributable to interstimulus competition. Electroencephalogram was measured while older and younger human adults responded to brief occurrences of coherent motion in an attended stimulus composed of randomly moving, orientation-defined, flickering bars. Attention was directed to horizontal or vertical bars by a pretrial cue, after which two orthogonally oriented, overlapping stimuli or a single stimulus were presented. Horizontal and vertical bars flickered at different frequencies and thereby elicited separable steady-state visual-evoked potentials, which were used to examine the effect of feature-based selection and the competitive influence of a second stimulus on ongoing visual processing. Age differences were found in feature-selective attentional modulation of visual responses: older adults did not show consistent modulation of magnitude or phase. In contrast, the suppressive effect of a second stimulus was robust and comparable in magnitude across age groups, suggesting that bottom-up processing of the current stimuli is essentially unchanged in healthy old age. Thus, it seems that visual processing per se is unchanged, but top-down attentional control is compromised in older adults when space cannot be used to guide selection.

Theoretical chemistry periodicities in chemistry and biology

CERN Document Server

Eyring, Henry

1978-01-01

Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

Rhythm generation through period concatenation in rat somatosensory cortex.

Directory of Open Access Journals (Sweden)

Mark A Kramer

2008-09-01

Full Text Available Rhythmic voltage oscillations resulting from the summed activity of neuronal populations occur in many nervous systems. Contemporary observations suggest that coexistent oscillations interact and, in time, may switch in dominance. We recently reported an example of these interactions recorded from in vitro preparations of rat somatosensory cortex. We found that following an initial interval of coexistent gamma ( approximately 25 ms period and beta2 ( approximately 40 ms period rhythms in the superficial and deep cortical layers, respectively, a transition to a synchronous beta1 ( approximately 65 ms period rhythm in all cortical layers occurred. We proposed that the switch to beta1 activity resulted from the novel mechanism of period concatenation of the faster rhythms: gamma period (25 ms+beta2 period (40 ms = beta1 period (65 ms. In this article, we investigate in greater detail the fundamental mechanisms of the beta1 rhythm. To do so we describe additional in vitro experiments that constrain a biologically realistic, yet simplified, computational model of the activity. We use the model to suggest that the dynamic building blocks (or motifs of the gamma and beta2 rhythms combine to produce a beta1 oscillation that exhibits cross-frequency interactions. Through the combined approach of in vitro experiments and mathematical modeling we isolate the specific components that promote or destroy each rhythm. We propose that mechanisms vital to establishing the beta1 oscillation include strengthened connections between a population of deep layer intrinsically bursting cells and a transition from antidromic to orthodromic spike generation in these cells. We conclude that neural activity in the superficial and deep cortical layers may temporally combine to generate a slower oscillation.

The Portrayal of Indigenous Health in Selected Australian Media

Directory of Open Access Journals (Sweden)

Melissa J. Stoneham

2014-04-01

Full Text Available It is acknowledged that health outcomes for Australian Indigenous peoples are lower than those of non-Indigenous Australians. Research suggests negative media in relation to Indigenous Australians perpetuates racist stereotypes among the wider population and impacts on the health of Indigenous Australians. This study examined the media portrayal of Indigenous Australian public health issues in selected media over a twelve month period and found that, overwhelmingly, the articles were negative in their portrayal of Indigenous health. A total of 74 percent of the coverage of Australian Indigenous related articles were negative, 15 percent were positive, and 11 percent were neutral. The most common negative subject descriptors related to alcohol, child abuse, petrol sniffing, violence, suicide, deaths in custody, and crime.

Pragmatic awareness of Suggestions: From (Im)Polite Mannerism to Attitudinal Appropriateness

OpenAIRE

Hamid Allami; Nasim Boustani

2017-01-01

The present research seeks to determine: (a) Iranian EFL learners’ application of suggestion semantic formulae ;(b) their attitude of appropriateness in terms of confidence in the employment of appropriate supportive moves; (c), their (im)polite mannerism with respect to the selected strategies; and (d) the relationship between attitude of appropriateness and mannerism of (im)politeness. An Oxford Quick placement Test (OQPT) was administered among 60 Iranian EFL learners to check their langua...

ERP Correlates of Encoding Success and Encoding Selectivity in Attention Switching

Science.gov (United States)

Yeung, Nick

2016-01-01

Long-term memory encoding depends critically on effective processing of incoming information. The degree to which participants engage in effective encoding can be indexed in electroencephalographic (EEG) data by studying event-related potential (ERP) subsequent memory effects. The current study investigated ERP correlates of memory success operationalised with two different measures—memory selectivity and global memory—to assess whether previously observed ERP subsequent memory effects reflect focused encoding of task-relevant information (memory selectivity), general encoding success (global memory), or both. Building on previous work, the present study combined an attention switching paradigm—in which participants were presented with compound object-word stimuli and switched between attending to the object or the word across trials—with a later recognition memory test for those stimuli, while recording their EEG. Our results provided clear evidence that subsequent memory effects resulted from selective attentional focusing and effective top-down control (memory selectivity) in contrast to more general encoding success effects (global memory). Further analyses addressed the question of whether successful encoding depended on similar control mechanisms to those involved in attention switching. Interestingly, differences in the ERP correlates of attention switching and successful encoding, particularly during the poststimulus period, indicated that variability in encoding success occurred independently of prestimulus demands for top-down cognitive control. These results suggest that while effects of selective attention and selective encoding co-occur behaviourally their ERP correlates are at least partly dissociable. PMID:27907075

Are Dysphoric Individuals More Suggestible or Less Suggestible Than Nondysphoric Individuals?

Science.gov (United States)

MacFarland, Wendy L.; Morris, Steven J.

1998-01-01

Dysphoric individuals are shown to be susceptible to interrogative suggestion, whether in the form of leading questions or interrogative pressure. The association of a clinically relevant condition of dysphoria (depression) with relatively high levels of suggestibility was investigated in a college student population (N=139). Applicability to…

Administration of antibiotics to ewes at the beginning of the dry-period.

Science.gov (United States)

Petridis, Ioannis G; Fthenakis, George C

2014-02-01

The objective of the present paper is to review the significance of administration of antibiotics at the end of a lactation period/beginning of the dry-period in ewes. During the stage of active involution, there is an increased risk of new mastitis cases and recrudescence of subclinical infections that had occurred during the previous lactation period. The main pathogens involved in the so-called 'dry-period mastitis' are coagulase-negative staphylococci. The principle of antibiotic administration at the end of a lactation period involves the intramammary infusion of a preparation to both mammary glands of ewes in the flock. Although a variety of products is licensed for administration in ewes, preferably the product for administration should be selected on the results of susceptibility testing of bacteria to be isolated from samples from ewes in the flock. In many clinical studies from around the world, performed in dairy- or mutton-production flocks, administration of antimicrobial agents at the end of a lactation period has been found beneficial in curing intramammary infections present at cessation of a lactation period, as well as in minimising the risk for intramammary infections during the dry-period. In dairy flocks, there are also benefits from increase in milk yield and decrease flock bulk milk mean somatic cell counts during the subsequent lactation period. Antibiotic administration at drying-off may be performed to all animals in a flock ('complete') or only to those considered to be infected ('selective'). In all cases, after administration of the antibiotic, definite and complete cessation of the lactation period is essential for success of the procedure. Moreover, maintenance of the prescribed withdrawal periods is essential to safeguard public health. The procedure should always be applied as part of a strategic udder health management plan in a flock; implementation improves the welfare of animals and affords significant financial benefits to the

Clionid sponge surveys on the Florida Reef Tract suggest land-based nutrient inputs

International Nuclear Information System (INIS)

Ward-Paige, Christine A.; Risk, Michael J.; Sherwood, Owen A.; Jaap, Walter C.

2005-01-01

Bioerosion by Cliona delitrix and Cliona lampa was assessed at 43 sites along the Florida Reef Tract, USA, in the summer of 2001. Sponge abundances were estimated using rapid visual assessment. Tissue samples of sponges were taken for analysis of δ 15 N. Comparison samples were taken from Belize. Annual trends in sponge abundance were estimated from archived videos covering the period from 1996 to 2001. Sites with the greatest boring sponge size and cover were in the Backcountry and Lower Keys, where total nitrogen, ammonium, and δ 15 N levels were highest. The sites with the largest relative increase of C. delitrix and C. lampa over the 5 year period were in the Upper Keys, where the greatest relative decline in stony coral cover has occurred. Florida sponge δ 15 N values were 5.2(±0.1)%, suggesting the influence of human waste; in comparison, offshore Belize samples were 2.1(±0.1)%. These results suggest sewage contamination of the Florida Reef Tract, shifting the carbonate balance from construction to destruction

Clionid sponge surveys on the Florida Reef Tract suggest land-based nutrient inputs

Energy Technology Data Exchange (ETDEWEB)

Ward-Paige, Christine A. [School of Geography and Geology, McMaster University, Hamilton, ON, L8S 4M1 (Canada)]. E-mail: cwardpai@dal.ca; Risk, Michael J. [School of Geography and Geology, McMaster University, Hamilton, ON, L8S 4M1 (Canada); Sherwood, Owen A. [Department of Earth Sciences, Dalhousie University, Halifax, NS, B3H 4J1 (Canada); Jaap, Walter C. [Florida Marine Research Institute, St. Petersburg, Florida (United States)

2005-07-01

Bioerosion by Cliona delitrix and Cliona lampa was assessed at 43 sites along the Florida Reef Tract, USA, in the summer of 2001. Sponge abundances were estimated using rapid visual assessment. Tissue samples of sponges were taken for analysis of {delta} {sup 15}N. Comparison samples were taken from Belize. Annual trends in sponge abundance were estimated from archived videos covering the period from 1996 to 2001. Sites with the greatest boring sponge size and cover were in the Backcountry and Lower Keys, where total nitrogen, ammonium, and {delta} {sup 15}N levels were highest. The sites with the largest relative increase of C. delitrix and C. lampa over the 5 year period were in the Upper Keys, where the greatest relative decline in stony coral cover has occurred. Florida sponge {delta} {sup 15}N values were 5.2({+-}0.1)%, suggesting the influence of human waste; in comparison, offshore Belize samples were 2.1({+-}0.1)%. These results suggest sewage contamination of the Florida Reef Tract, shifting the carbonate balance from construction to destruction.

Balancing selection maintains cryptic colour morphs.

Science.gov (United States)

Wellenreuther, Maren

2017-11-01

Animals display incredibly diverse colour patterns, a testament to evolution's endless innovation in shaping life. In many species, the interplay between males and females in the pursuit of mates has driven the evolution of a myriad of colour forms, from the flashy peacock tail feathers to the tiniest colour markings in damselflies. In others, colour provides crypsis by allowing to blend into the background and to escape the eyes of predators. While the obvious benefits of this dazzling diversity for reproduction and survival seem straightforward, its maintenance is not. Theory predicts that genetic drift and various forms of selection reduce variation over time, making the persistence of colour variants over generations a puzzle. In this issue of Molecular Ecology, Lindtke et al. () study the cryptic colour morphs of Timema cristinae walking sticks to shed light on the genetic architecture and mechanisms that allow colour polymorphism maintenance over long timescales. By combining genome-wide data with phenotyping information from natural populations, they were able to map the green and melanistic colour to one genomic region with highly reduced effective recombination rate between two main chromosomal variants, consistent with an inversion polymorphism. These two main chromosomal variants showed geographically widespread heterozygote excess, and genomic signatures consistent with long-term balancing selection. A younger chromosomal variant was detected for the third morph, the green-striped colour morphs, in the same genomic regions as the melanistic and the green-unstriped morphs. Together, these results suggest that the genetic architecture of cryptic T. cristinae morphs is caused by nonrecombining genomic blocks that have been maintained over extended time periods by balancing selection making this study one of the few available empirical examples documenting that balancing selection of various forms may play an important role in maintaining adaptive genetic

How much should I eat? A comparison of suggested portion sizes in the UK

OpenAIRE

Lewis, Hannah B; Ahern, Amy L; Jebb, Susan A

2012-01-01

Objective To identify and compare suggested food portion sizes in UK schemes. Design The study collated and compared suggested portion sizes from selected UK schemes intended both for general advice and weight-loss advice. Setting Portion size schemes were included if they were relevant to the UK, provided actual portion size information, were intended for adults and were obtainable from the public domain in November 2010. Included schemes were from the food industry, non-governmental organis...

Crop Growing Periods and Irrigation Needs in Bahia State North ...

African Journals Online (AJOL)

Markov chain probabilities of days with dry and wet soil were computed for each decade of the year. Soil moisture averages and probabilities were used to determine the optimum crop growing periods at the stations. The amounts of supplementary irrigation necessary to maintain the soil moisture above selected levels ...

Selecting for memory? The influence of selective attention on the mnemonic binding of contextual information.

Science.gov (United States)

Uncapher, Melina R; Rugg, Michael D

2009-06-24

Not all of what is experienced is remembered later. Behavioral evidence suggests that the manner in which an event is processed influences which aspects of the event will later be remembered. The present experiment investigated the neural correlates of "selective encoding," or the mechanisms that support the encoding of some elements of an event in preference to others. Event-related MRI data were acquired while volunteers selectively attended to one of two different contextual features of study items (color or location). A surprise memory test for the items and both contextual features was subsequently administered to determine the influence of selective attention on the neural correlates of contextual encoding. Activity in several cortical regions indexed later memory success selectively for color or location information, and this encoding-related activity was enhanced by selective attention to the relevant feature. Critically, a region in the hippocampus responded selectively to attended source information (whether color or location), demonstrating encoding-related activity for attended but not for nonattended source features. Together, the findings suggest that selective attention modulates the magnitude of activity in cortical regions engaged by different aspects of an event, and hippocampal encoding mechanisms seem to be sensitive to this modulation. Thus, the information that is encoded into a memory representation is biased by selective attention, and this bias is mediated by cortical-hippocampal interactions.

Selecting for memory? The influence of selective attention on the mnemonic binding of contextual information

Science.gov (United States)

Uncapher, Melina R.; Rugg, Michael D.

2009-01-01

Not all of what is experienced is remembered later. Behavioral evidence suggests that the manner in which an event is processed influences which aspects of the event will later be remembered. The present experiment investigated the neural correlates of ‘selective encoding’, or the mechanisms that support the encoding of some elements of an event in preference to others. Event-related functional magnetic resonance imaging (fMRI) data were acquired while volunteers selectively attended to one of two different contextual features of study items (color or location). A surprise memory test for the items and both contextual features was subsequently administered to determine the influence of selective attention on the neural correlates of contextual encoding. Activity in several cortical regions indexed later memory success selectively for color or location information, and this encoding-related activity was enhanced by selective attention to the relevant feature. Critically, a region in the hippocampus responded selectively to attended source information (whether color or location), demonstrating encoding-related activity for attended but not for nonattended source features. Together, the findings suggest that selective attention modulates the magnitude of activity in cortical regions engaged by different aspects of an event, and hippocampal encoding mechanisms seem to be sensitive to this modulation. Thus, the information that is encoded into a memory representation is biased by selective attention, and this bias is mediated by cortico-hippocampal interactions. PMID:19553466

Domestication and tameness: brain gene expression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology.

Science.gov (United States)

Bélteky, Johan; Agnvall, Beatrix; Johnsson, Martin; Wright, Dominic; Jensen, Per

2016-08-01

The domestication of animals has generated a set of phenotypic modifications, affecting behaviour, appearance, physiology and reproduction, which are consistent across a range of species. We hypothesized that some of these phenotypes could have evolved because of genetic correlation to tameness, an essential trait for successful domestication. Starting from an outbred population of red junglefowl, ancestor of all domestic chickens, we selected birds for either high or low fear of humans for five generations. Birds from the fifth selected generation (S 5 ) showed a divergent pattern of growth and reproduction, where low fear chickens grew larger and produced larger offspring. To examine underlying genetic mechanisms, we used microarrays to study gene expression in thalamus/hypothalamus, a brain region involved in fear and stress, in both the parental generation and the S 5 . While parents of the selection lines did not show any differentially expressed genes, there were a total of 33 genes with adjusted p -values below 0.1 in S 5 . These were mainly related to sperm-function, immunological functions, with only a few known to be relevant to behaviour. Hence, five generations of divergent selection for fear of humans produced changes in hypothalamic gene expression profiles related to pathways associated with male reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis that domesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

Long-Period Solar Variability

Energy Technology Data Exchange (ETDEWEB)

GAUTHIER,JOHN H.

2000-07-20

Terrestrial climate records and historical observations of the Sun suggest that the Sun undergoes aperiodic oscillations in radiative output and size over time periods of centuries and millenia. Such behavior can be explained by the solar convective zone acting as a nonlinear oscillator, forced at the sunspot-cycle frequency by variations in heliomagnetic field strength. A forced variant of the Lorenz equations can generate a time series with the same characteristics as the solar and climate records. The timescales and magnitudes of oscillations that could be caused by this mechanism are consistent with what is known about the Sun and terrestrial climate.

Testing for the Occurrence of Selective Episodes During the Divergence of Otophysan Fishes: Insights from Mitogenomics.

Science.gov (United States)

D'Anatro, Alejandro; Giorello, Facundo; Feijoo, Matías; Lessa, Enrique P

2017-04-01

How natural selection shapes biodiversity constitutes a topic of renewed interest during the last few decades. The division Otophysi comprises approximately two-thirds of freshwater fish diversity and probably underwent an extensive adaptive radiation derived from a single invasion of the supercontinent Pangaea, giving place to the evolution of the main five Otophysan lineages during a short period of time. Little is known about the factors involved in the processes that lead to lineage diversification among this group of fishes and identifying directional selection acting over protein-coding genes could offer clues about the processes acting on species diversification. The main objective of this study was to explore the otophysan mitochondrial genome evolution, in order to account for the possible signatures of selective events in this lineage, and to explore for the functional connotations of these molecular substitutions. Mainly, three different approaches were used: the "ω-based" BS-REL and MEME methods, implemented in the DATAMONKEY web server, and analysis of selection on amino acid properties, implemented in the software TreeSAAP. We found evidence of selective episodes along several branches of the evolutionary history of othophysan fishes. Analyses carried out using the BS-REL algorithm suggest episodic diversifying selection at basal branches of the otophysan lineage, which was also supported by analyses implemented in MEME and TreeSAAP. These results suggest that throughout the Siluriformes radiation, an important number of adaptive changes occurred in their mitochondrial genome. The metabolic consequences and ecological correlates of these molecular substitutions should be addressed in future studies.

Non-adaptive territory selection by a bird with exceptionally long parental care

Directory of Open Access Journals (Sweden)

Radosław Włodarczyk

2016-03-01

Full Text Available High-quality territories are expected to provide greater fitness return for breeding individuals and, thus, are likely to have higher long-term occupation rate in comparison to low-quality territories. However, if environmental and ecological cues used for territory selection cannot reliably predict true territory quality, a mismatch between preferences and fitness may occur. We suggest that this kind of non-adaptive territory selection is more likely in species with long reproductive cycles, as a long time interval between territory establishment and young fledgling should reduce predictability of conditions during the critical stages of brood care. In this study, we investigated adaptiveness of territory selection in a migratory bird with exceptionally long parental care, the mute swan Cygnus olor, which requires over four months to complete the entire reproductive cycle from egg laying to young fledging. For this purpose, we collected information on the long-term (10–19 years occupancy of 222 swan breeding territories and correlated it with reproductive performance (n = 1,345 breeding attempts and body condition of breeding adults. We found that long-term occupancy positively correlated with the timing of breeding, suggesting that individuals settled earlier in the attractive, frequently occupied territories. By contrast, we found no relationship between territory occupancy and reproductive output (hatching and fledging success or adult body condition. The results indicate that at the time of territory selection swans might not be able to reliably assess territory quality, likely due to: (1 exceptionally long period of parental care, which reduces temporal correlation between the conditions at the time of territory selection and conditions during chick rearing; and (2 unpredictability of human-related activities that had a major impact on reproductive output of swan pairs in our population.

Selective Nonoperative Management of Penetrating Abdominal Solid Organ Injuries

Science.gov (United States)

Demetriades, Demetrios; Hadjizacharia, Pantelis; Constantinou, Costas; Brown, Carlos; Inaba, Kenji; Rhee, Peter; Salim, Ali

2006-01-01

Objective: To assess the feasibility and safety of selective nonoperative management in penetrating abdominal solid organ injuries. Background: Nonoperative management of blunt abdominal solid organ injuries has become the standard of care. However, routine surgical exploration remains the standard practice for all penetrating solid organ injuries. The present study examines the role of nonoperative management in selected patients with penetrating injuries to abdominal solid organs. Patients and Methods: Prospective, protocol-driven study, which included all penetrating abdominal solid organ (liver, spleen, kidney) injuries admitted to a level I trauma center, over a 20-month period. Patients with hemodynamic instability, peritonitis, or an unevaluable abdomen underwent an immediate laparotomy. Patients who were hemodynamically stable and had no signs of peritonitis were selected for further CT scan evaluation. In the absence of CT scan findings suggestive of hollow viscus injury, the patients were observed with serial clinical examinations, hemoglobin levels, and white cell counts. Patients with left thoracoabdominal injuries underwent elective laparoscopy to rule out diaphragmatic injury. Outcome parameters included survival, complications, need for delayed laparotomy in observed patients, and length of hospital stay. Results: During the study period, there were 152 patients with 185 penetrating solid organ injuries. Gunshot wounds accounted for 70.4% and stab wounds for 29.6% of injuries. Ninety-one patients (59.9%) met the criteria for immediate operation. The remaining 61 (40.1%) patients were selected for CT scan evaluation. Forty-three patients (28.3% of all patients) with 47 solid organ injuries who had no CT scan findings suspicious of hollow viscus injury were selected for clinical observation and additional laparoscopy in 2. Four patients with a “blush” on CT scan underwent angiographic embolization of the liver. Overall, 41 patients (27

A Bayesian test for periodic signals in red noise

Science.gov (United States)

Vaughan, S.

2010-02-01

Many astrophysical sources, especially compact accreting sources, show strong, random brightness fluctuations with broad power spectra in addition to periodic or quasi-periodic oscillations (QPOs) that have narrower spectra. The random nature of the dominant source of variance greatly complicates the process of searching for possible weak periodic signals. We have addressed this problem using the tools of Bayesian statistics; in particular, using Markov Chain Monte Carlo techniques to approximate the posterior distribution of model parameters, and posterior predictive model checking to assess model fits and search for periodogram outliers that may represent periodic signals. The methods developed are applied to two example data sets, both long XMM-Newton observations of highly variable Seyfert 1 galaxies: RE J1034 + 396 and Mrk 766. In both cases, a bend (or break) in the power spectrum is evident. In the case of RE J1034 + 396, the previously reported QPO is found but with somewhat weaker statistical significance than reported in previous analyses. The difference is due partly to the improved continuum modelling, better treatment of nuisance parameters and partly to different data selection methods.

Classification of hadith into positive suggestion, negative suggestion, and information

Science.gov (United States)

Faraby, Said Al; Riviera Rachmawati Jasin, Eliza; Kusumaningrum, Andina; Adiwijaya

2018-03-01

As one of the Muslim life guidelines, based on the meaning of its sentence(s), a hadith can be viewed as a suggestion for doing something, or a suggestion for not doing something, or just information without any suggestion. In this paper, we tried to classify the Bahasa translation of hadith into the three categories using machine learning approach. We tried stemming and stopword removal in preprocessing, and TF-IDF of unigram, bigram, and trigram as the extracted features. As the classifier, we compared between SVM and Neural Network. Since the categories are new, so in order to compare the results of the previous pipelines, we created a baseline classifier using simple rule-based string matching technique. The rule-based algorithm conditions on the occurrence of words such as “janganlah, sholatlah, and so on” to determine the category. The baseline method achieved F1-Score of 0.69, while the best F1-Score from the machine learning approach was 0.88, and it was produced by SVM model with the linear kernel.

Environmental Pollution, A Selective Bibliography.

Science.gov (United States)

Clearinghouse for Federal Scientific and Technical Information, Springfield, VA.

This bibliography on environmental pollution is comprised primarily of reports of federally sponsored research by such departments and agencies as HEW, Interior, AEC, NASA, Defense, Transportation, and others. The reports were selected from Clearinghouse announcement journals during the period 1968 through April 1970. The bibliography contains…

Commodity profiles for selected metals

International Nuclear Information System (INIS)

Svoboda, O.; Wilson, B.M.

1985-01-01

This report describes the basic characteristics of 35 metals and gives the prices and production of these metals for the period 1979 to 1983/4. The description of each metal includes the ore grades and reserves, the major minerals in which the metal occurs, and the discovery, selected physical properties, sources, uses, substitutes, and effects on the environment of the metal. Graphs showing price and production cover the period 1950 to 1984, and possible future developments in these areas are forecast for each metal until the year 2000

Chelating extractants of improved selectivity. Progress report for period November 1, 1977--July 31 1978

International Nuclear Information System (INIS)

Freiser, H.

1978-08-01

During the current contract period, the high susceptibility of lanthanide chelate stability to steric hindrance was confirmed. The increase in coordination number of lanthanides from lanthanum to ytterbium as evidenced from extraction equilibria serves to increase their separability. 8-Quinolinol immobilized on silica can separate lanthanide ions

Suggestions on R and D work of high-level radioactive waste disposal in China

International Nuclear Information System (INIS)

Xu Guoqing

2012-01-01

The difference between repository and generic underground facilities is described. Some differences and similarities of site selection between the low and medium radioactive waste disposal, nuclear power station and high-level radioactive waste repository are also discussed here. We trend to extremely emphasize the safety of high-level radioactive waste disposal because of high toxicity, long half-life and long safety disposal period of this kind of radioactive wastes; because radioactive waste in the repository is of high specific activities and buried in depth, it would be difficult to meddle with its safety. In case of repository system being destroyed, the author considers that in the stages of regional and area site selection, the first task is to investigate regional tectonic stability. Some problems about disposal options and others are also discussed in this paper. (author)

External Periodic Force Control of a Single-Degree-of-Freedom Vibroimpact System

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Jingyue Wang

2013-01-01

Full Text Available A single-degree-of-freedom mechanical model of vibro-impact system is established. Bifurcation and chaos in the system are revealed with the time history diagram, phase trajectory map, and Poincaré map. According to the bifurcation and chaos of the actual vibro-impact system, the paper puts forward external periodic force control strategy. The method of controlling chaos by external periodic force feedback controller is developed to guide chaotic motions towards regular motions. The stability of the control system is also analyzed especially by theory. By selecting appropriate feedback coefficients, the unstable periodic orbits of the original chaotic orbit can be stabilized to the stable periodic orbits. The effectiveness of this control method is verified by numerical simulation.

Conditional control in visual selection

NARCIS (Netherlands)

van Zoest, Wieske; Van der Stigchel, Stefan; Donk, Mieke

2017-01-01

Attention and eye movements provide a window into the selective processing of visual information. Evidence suggests that selection is influenced by various factors and is not always under the strategic control of the observer. The aims of this tutorial review are to give a brief introduction to eye

Directional selection causes decanalization in a group I ribozyme.

Science.gov (United States)

Hayden, Eric J; Weikert, Christian; Wagner, Andreas

2012-01-01

A canalized genotype is robust to environmental or genetic perturbations. Canalization is expected to result from stabilizing selection on a well-adapted phenotype. Decanalization, the loss of robustness, might follow periods of directional selection toward a new optimum. The evolutionary forces causing decanalization are still unknown, in part because it is difficult to determine the fitness effects of mutations in populations of organisms with complex genotypes and phenotypes. Here, we report direct experimental measurements of robustness in a system with a simple genotype and phenotype, the catalytic activity of an RNA enzyme. We find that the robustness of a population of RNA enzymes decreases during a period of directional selection in the laboratory. The decrease in robustness is primarily caused by the selective sweep of a genotype that is decanalized relative to the wild-type, both in terms of mutational robustness and environmental robustness (thermodynamic stability). Our results experimentally demonstrate that directional selection can cause decanalization on short time scales, and demonstrate co-evolution of mutational and environmental robustness.

Distractor Inhibition: Principles of Operation during Selective Attention

Science.gov (United States)

Wyatt, Natalie; Machado, Liana

2013-01-01

Research suggests that although target amplification acts as the main determinant of the efficacy of selective attention, distractor inhibition contributes under some circumstances. Here we aimed to gain insight into the operating principles that regulate the use of distractor inhibition during selective attention. The results suggest that, in…

Early processing variations in selective attention to the color and direction of moving stimuli during 30 days head-down bed rest

Science.gov (United States)

Wang, Lin-Jie; He, Si-Yang; Niu, Dong-Bin; Guo, Jian-Ping; Xu, Yun-Long; Wang, De-Sheng; Cao, Yi; Zhao, Qi; Tan, Cheng; Li, Zhi-Li; Tang, Guo-Hua; Li, Yin-Hui; Bai, Yan-Qiang

2013-11-01

Dynamic variations in early selective attention to the color and direction of moving stimuli were explored during a 30 days period of head-down bed rest. Event-related potentials (ERPs) were recorded at F5, F6, P5, P6 scalp locations in seven male subjects who attended to pairs of bicolored light emitting diodes that flashed sequentially to produce a perception of movement. Subjects were required to attend selectively to a critical feature of the moving target, e.g., color or direction. The tasks included: a no response task, a color selective response task, a moving direction selective response task, and a combined color-direction selective response task. Subjects were asked to perform these four tasks on: the 3rd day before bed rest; the 3rd, 15th and 30th day during the bed rest; and the 5th day after bed rest. Subjects responded quickly to the color than moving direction and combined color-direction response. And they had a longer reaction time during bed rest on the 15th and 30th day during bed rest after a relatively quicker response on the 3rd day. Using brain event-related potentials technique, we found that in the color selective response task, the mean amplitudes of P1 and N1 for target ERPs decreased in the 3rd day during bed rest and 5th day after bed rest in comparison with pre-bed rest, 15th day and 30th day during bed rest. In the combined color-direction selective response task, the P1 latencies for target ERPs on the 3rd and 30th day during bed rest were longer than on the 15th day during bed rest. As 3rd day during bed rest was in the acute adaptation period and 30th day during bed rest was in the relatively adaptation stage of head-down bed rest, the results help to clarify the effects of bed rest on different task loads and patterns of attention. It was suggested that subjects expended more time to give correct decision in the head-down tilt bed rest state. A difficulty in the recruitment of brain resources was found in feature selection task

A periodic pattern of SNPs in the human genome

DEFF Research Database (Denmark)

Madsen, Bo Eskerod; Villesen, Palle; Wiuf, Carsten

2007-01-01

By surveying a filtered, high-quality set of SNPs in the human genome, we have found that SNPs positioned 1, 2, 4, 6, or 8 bp apart are more frequent than SNPs positioned 3, 5, 7, or 9 bp apart. The observed pattern is not restricted to genomic regions that are known to cause sequencing...... periodic DNA. Our results suggest that not all SNPs in the human genome are created by independent single nucleotide mutations, and that care should be taken in analysis of SNPs from periodic DNA. The latter may have important consequences for SNP and association studies....... or alignment errors, for example, transposable elements (SINE, LINE, and LTR), tandem repeats, and large duplicated regions. However, we found that the pattern is almost entirely confined to what we define as "periodic DNA." Periodic DNA is a genomic region with a high degree of periodicity in nucleotide usage...

Selection of artificial gravity by animals during suborbital rocket flights

Science.gov (United States)

Lange, K. O.; Belleville, R. E.; Clark, F. C.

1975-01-01

White rats selected preferred artificial gravity levels by locomotion in centrifuges consisting of two runways mounted in the nose of sounding rockets. Roll rate of the Aerobee 150A rocket was designed to produce an angular velocity of 45 rpm during 5 min of free-fall, providing a gravity range from 0.3 to 1.5 G depending on a subject's runway position. One animal was released at the high and one at the low gravity position in each flight. Animal positions were continuously recorded. Locomotion patterns during these flights were similar. All four animals explored the entire available G-range. One rat settled at 0.4 G after 2 min; the others crossed the 1-G location in progressively narrower excursions and were near earth gravity at the end of the test period. Tentatively, the data suggest that normal earth-reared rats select earth gravity when available magnitudes include values above and below 1 G. Modification of gravity preference by prolonged exposure to higher or lower levels remains a possibility.

STRUCTURE AND NUTRITIVE VALUE OF DEFERRED PASTURE OF BRACHIARIA DECUMBENS CV. BASILISK DURING THE GRAZING PERIOD

Directory of Open Access Journals (Sweden)

Manoel Eduardo Rozalino Santos

2011-07-01

Full Text Available The experiment aimed to understand the effect of grazing period on morphology and nutritive value of deferred Brachiaria decumbens cv. Basilisk pasture and on hand-plucking sample with cattle. Subdivided plots were used according to a randomized block design with two replicates. Four grazing periods (1, 31, 57 and 88 days and two forage samples (available in pasture (AP and obtained by hand-plucking (HP were studied. The live leaf laminae (LLL, potentially digestible neutral detergent fiber (PDNDF, potentially digestible dry matter (PDDM and crude protein (CP levels were higher and dead leaf laminae (DLL, and dead stem (DS, neutral detergent fiber (NDF and indigestible NDF percentages were lower in sample of HP in relation to forage AP. The grazing period decreased linearly the LLL, PDNDF, PDDM percentages, as well as increased linearly DS and indigestible NDF levels in forages. The potential selectivity indexes (PSI of LLL and indigestible NDF increased linearly with grazing period. The PSI of live stem was smaller and the PSI of CP was higher in interim periods of grazing. The reduction in deferring period results in B. decumbens with better morphological composition and nutritional value, which favors the animal selectivity.

Host-Parasite Interactions and Purifying Selection in a Microsporidian Parasite of Honey Bees.

Science.gov (United States)

Huang, Qiang; Chen, Yan Ping; Wang, Rui Wu; Cheng, Shang; Evans, Jay D

2016-01-01

To clarify the mechanisms of Nosema ceranae parasitism, we deep-sequenced both honey bee host and parasite mRNAs throughout a complete 6-day infection cycle. By time-series analysis, 1122 parasite genes were significantly differently expressed during the reproduction cycle, clustering into 4 expression patterns. We found reactive mitochondrial oxygen species modulator 1 of the host to be significantly down regulated during the entire infection period. Our data support the hypothesis that apoptosis of honey bee cells was suppressed during infection. We further analyzed genome-wide genetic diversity of this parasite by comparing samples collected from the same site in 2007 and 2013. The number of SNP positions per gene and the proportion of non-synonymous substitutions per gene were significantly reduced over this time period, suggesting purifying selection on the parasite genome and supporting the hypothesis that a subset of N. ceranae strains might be dominating infection.

[Challenge and opportunity of entry to WTO brings to scientific and technological periodical].

Science.gov (United States)

Tian, Yun-Mei

2004-11-01

After our country enters WTO, confronted with the direct influence in big international market opening, editorial department will face fierce competition. Selecting the superior and eliminate the inferior will test every publishing house and every magazine directly. In order to improve the competition level, author has analyzed the current situation of China's periodical development, and then explored the scientific and technological periodical opportunity and challenge faced under the new situation.

Small calcified lesions suggestive of neurocysticercosis are associated with mesial temporal sclerosis

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Marcos C. B. Oliveira

2014-07-01

Full Text Available Recent studies have suggested a possible relationship between temporal lobe epilepsy with mesial temporal sclerosis (MTS and neurocysticercosis (NC. We performed a case-control study to evaluate the association of NC and MTS. Method: We randomly selected patients with different epilepsy types, including: MTS, primary generalized epilepsy (PGE and focal symptomatic epilepsy (FSE. Patients underwent a structured interview, followed by head computed tomography (CT. A neuroradiologist evaluated the scan for presence of calcified lesions suggestive of NC. CT results were matched with patients’ data. Results: More patients in the MTS group displayed calcified lesions suggestive of NC than patients in the other groups (p=0.002. On multivariate analysis, MTS was found to be an independent predictor of one or more calcified NC lesions (p=0.033. Conclusion: After controlling for confounding factors, we found an independent association between NC calcified lesions and MTS.

Response to family selection and genetic parameters in Japanese quail selected for four week breast weight

DEFF Research Database (Denmark)

Khaldari, Majid; Yeganeh, Hassan Mehrabani; Pakdel, Abbas

2011-01-01

An experiment was conducted to investigate the effect of short-term selection for 4 week breast weight (4wk BRW), and to estimate genetic parameters of body weight, and carcass traits. A selection (S) line and control (C) line was randomly selected from a base population. Data were collected over...... was 0.35±0.06. There were a significant difference for BW, and carcass weights but not for carcass percent components between lines (Pcarcass and leg weights were 0.46, 0.41 and 0.47, and 13.2, 16.2, 4.4 %, respectively....... The genetic correlations of BRW with BW, carcass, leg, and back weights were 0.85, 0.88 and 0.72, respectively. Selection for 4 wk BRW improved feed conversion ratio (FCR) about 0.19 units over the selection period. Inbreeding caused an insignificant decline of the mean of some traits. Results from...

Dynamic selection of ship responses for estimation of on-site directional wave spectra

DEFF Research Database (Denmark)

Andersen, Ingrid Marie Vincent; Storhaug, Gaute

2012-01-01

-estimate of the wave spectrum is suggested. The selection method needs to be robust for what reason a parameterised uni-directional, two-parameter wave spectrum is treated. The parameters included are the zero up-crossing period, the significant wave height and the main wave direction relative to the ship’s heading...... with the best overall agreement are selected for the actual estimation of the directional wave spectrum. The transfer functions for the ship responses can be determined using different computational methods such as striptheory, 3D panel codes, closed form expressions or model tests. The uncertainty associated......Knowledge of the wave environment in which a ship is operating is crucial for most on-board decision support systems. Previous research has shown that the directional wave spectrum can be estimated by the use of measured global ship responses and a set of transfer functions determined...

Diffuse scattering from periodic and aperiodic crystals

International Nuclear Information System (INIS)

Frey, F.

1997-01-01

A (selective) review on diffuse scattering from periodic and aperiodic crystalline solids is given to demonstrate the wide field of applications in basic and applied research. After a general introduction in this field each topic is exemplified by one or two examples. Main emphasis is laid on recent work. More established work, e.g., on diffuse scattering from metals and alloys, polytypes, stacking disorder from layered structures, etc. is omitted due to the availability of excellent textbooks and reviews. Finally a short summary of recent developments of experimental methods and evaluation techniques is presented. (orig.)

Fabrication of Long Period Gratings by Periodically Removing the Coating of Cladding-Etched Single Mode Optical Fiber Towards Optical Fiber Sensor Development.

Science.gov (United States)

Ascorbe, Joaquin; Corres, Jesus M; Del Villar, Ignacio; Matias, Ignacio R

2018-06-07

Here, we present a novel method to fabricate long period gratings using standard single mode optical fibers (SMF). These optical devices were fabricated in a three-step process, which consisted of etching the SMF, then coating it with a thin-film and, the final step, which involved removing sections of the coating periodically by laser ablation. Tin dioxide was chosen as the material for this study and it was sputtered using a pulsed DC sputtering system. Theoretical simulations were performed in order to select the appropriate parameters for the experiments. The responses of two different devices to different external refractive indices was studied, and the maximum sensitivity obtained was 6430 nm/RIU for external refractive indices ranging from 1.37 to 1.39.

Fabrication of Long Period Gratings by Periodically Removing the Coating of Cladding-Etched Single Mode Optical Fiber Towards Optical Fiber Sensor Development

Directory of Open Access Journals (Sweden)

Joaquin Ascorbe

2018-06-01

Full Text Available Here, we present a novel method to fabricate long period gratings using standard single mode optical fibers (SMF. These optical devices were fabricated in a three-step process, which consisted of etching the SMF, then coating it with a thin-film and, the final step, which involved removing sections of the coating periodically by laser ablation. Tin dioxide was chosen as the material for this study and it was sputtered using a pulsed DC sputtering system. Theoretical simulations were performed in order to select the appropriate parameters for the experiments. The responses of two different devices to different external refractive indices was studied, and the maximum sensitivity obtained was 6430 nm/RIU for external refractive indices ranging from 1.37 to 1.39.

Agatha: Disentangling period signals from correlated noise in a periodogram framework

Science.gov (United States)

Feng, F.; Tuomi, M.; Jones, H. R. A.

2018-04-01

Agatha is a framework of periodograms to disentangle periodic signals from correlated noise and to solve the two-dimensional model selection problem: signal dimension and noise model dimension. These periodograms are calculated by applying likelihood maximization and marginalization and combined in a self-consistent way. Agatha can be used to select the optimal noise model and to test the consistency of signals in time and can be applied to time series analyses in other astronomical and scientific disciplines. An interactive web implementation of the software is also available at http://agatha.herts.ac.uk/.

Non-selective vs. selective beta-blocker treatment and the risk of thrombo-embolic events in patients with heart failure

NARCIS (Netherlands)

de Peuter, Olav R.; Souverein, Patrick C.; Klungel, Olaf H.; Büller, Harry R.; de Boer, Anthonius; Kamphuisen, Pieter W.

2011-01-01

Aims Heart failure (HF) is associated with a prothrombotic state, resulting in an increased risk for thrombo-embolic events. Studies suggest a reduced prothrombotic state when non-selective beta-blockers relative to selective beta-blockers are given. We studied the influence of non-selective

Pragmatic awareness of Suggestions: From (ImPolite Mannerism to Attitudinal Appropriateness

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Hamid Allami

2017-09-01

Full Text Available The present research seeks to determine: (a Iranian EFL learners’ application of suggestion semantic formulae ;(b their attitude of appropriateness in terms of confidence in the employment of appropriate supportive moves; (c, their (impolite mannerism with respect to the selected strategies; and (d the relationship between attitude of appropriateness and mannerism of (impoliteness. An Oxford Quick placement Test (OQPT was administered among 60 Iranian EFL learners to check their language proficiency level and to satisfy the assumption of homogeneity among the learners. These participants along with 10 American native speakers then underwent a suggestion DCT. The questionnaire included questions addressing interlocutors’ with higher, lower or equal power status and intimate or strange social distance. The DCT also involved attitudinal appropriateness scale and (impoliteness mannerism likert scale to examine the learners’ degree of confidence and mannerism. Besides similarities and differences in the application of suggestion semantic formulae between the Iranian learners and American speakers, the results revealed variations in the two groups’ performances for appropriateness and (impoliteness. The results also indicated a positive relationship between the attitude and mannerism scales.

Creativity-the unconscious foundations of the incubation period

NARCIS (Netherlands)

Ritter, S.M.; Dijksterhuis, A.J.

2014-01-01

Creativity is one of the most important assets we have to navigate through the fast changing world of the 21st century. Anecdotal accounts of creative individuals suggest that oftentimes, creative discoveries result from a process whereby initial conscious thought is followed by a period during

Selected Reference Books of 1998.

Science.gov (United States)

McIlvaine, Eileen

1999-01-01

Reviews a selection of recent scholarly and general reference works under the categories of Periodicals and Newspapers, Philosophy, Literature, Film and Radio, Art and Architecture, Music, Political Science, Women's Studies, and History. A brief summary of new editions of standard works is provided at the end of the articles. (AEF)

Genome-wide scan of gastrointestinal nematode resistance in closed Angus population selected for minimized influence of MHC.

Science.gov (United States)

Kim, Eui-Soo; Sonstegard, Tad S; da Silva, Marcos V G B; Gasbarre, Louis C; Van Tassell, Curtis P

2015-01-01

Genetic markers associated with parasite indicator traits are ideal targets for study of marker assisted selection aimed at controlling infections that reduce herd use of anthelminthics. For this study, we collected gastrointestinal (GI) nematode fecal egg count (FEC) data from post-weaning animals of an Angus resource population challenged to a 26 week natural exposure on pasture. In all, data from 487 animals was collected over a 16 year period between 1992 and 2007, most of which were selected for a specific DRB1 allele to reduce the influence of potential allelic variant effects of the MHC locus. A genome-wide association study (GWAS) based on BovineSNP50 genotypes revealed six genomic regions located on bovine Chromosomes 3, 5, 8, 15 and 27; which were significantly associated (-log10 p=4.3) with Box-Cox transformed mean FEC (BC-MFEC). DAVID analysis of the genes within the significant genomic regions suggested a correlation between our results and annotation for genes involved in inflammatory response to infection. Furthermore, ROH and selection signature analyses provided strong evidence that the genomic regions associated BC-MFEC have not been affected by local autozygosity or recent experimental selection. These findings provide useful information for parasite resistance prediction for young grazing cattle and suggest new candidate gene targets for development of disease-modifying therapies or future studies of host response to GI parasite infection.

Influence of prey body characteristics and performance on predator selection.

Science.gov (United States)

Holmes, Thomas H; McCormick, Mark I

2009-03-01

At the time of settlement to the reef environment, coral reef fishes differ in a number of characteristics that may influence their survival during a predatory encounter. This study investigated the selective nature of predation by both a multi-species predator pool, and a single common predator (Pseudochromis fuscus), on the reef fish, Pomacentrus amboinensis. The study focused on the early post-settlement period of P. amboinensis, when mortality, and hence selection, is known to be highest. Correlations between nine different measures of body condition/performance were examined at the time of settlement, in order to elucidate the relationships between different traits. Single-predator (P. fuscus) choice trials were conducted in 57.4-l aquaria with respect to three different prey characteristics [standard length (SL), body weight and burst swimming speed], whilst multi-species trials were conducted on open patch reefs, manipulating prey body weight only. Relationships between the nine measures of condition/performance were generally poor, with the strongest correlations occurring between the morphological measures and within the performance measures. During aquaria trials, P. fuscus was found to be selective with respect to prey SL only, with larger individuals being selected significantly more often. Multi-species predator communities, however, were selective with respect to prey body weight, with heavier individuals being selected significantly more often than their lighter counterparts. Our results suggest that under controlled conditions, body length may be the most important prey characteristic influencing prey survival during predatory encounters with P. fuscus. In such cases, larger prey size may actually be a distinct disadvantage to survival. However, these relationships appear to be more complex under natural conditions, where the expression of prey characteristics, the selectivity fields of a number of different predators, their relative abundance, and

A copper ion-selective electrode with high selectivity prepared by sol-gel and coated wire techniques.

Science.gov (United States)

Mazloum Ardakani, M; Salavati-Niasari, M; Khayat Kashani, M; Ghoreishi, S M

2004-03-01

A sol-gel electrode and a coated wire ion-selective poly(vinyl chloride) membrane, based on thiosemicarbazone as a neutral carrier, were successfully developed for the detection of Cu (II) in aqueous solutions. The sol-gel electrode and coated electrode exhibited linear response with Nernstian slopes of 29.2 and 28.1 mV per decade respectively, within the copper ion concentration ranges 1.0 x 10(-5) - 1.0 x 10(-1) M and 6.0 x 10(-6) - 1.0 x 10(-1) M for coated and sol-gel sensors. The coated and sol-gel electrodes show detection limits of 3.0 x 10(-6) and 6.0 x 10(-6) M respectively. The electrodes exhibited good selectivities for a number of alkali, alkaline earth, transition and heavy metal ions. The proposed electrodes have response times ranging from 10-50 s to achieve a 95% steady potential for Cu2+ concentration. The electrodes are suitable for use in aqueous solutions over a wide pH range (4-7.5). Applications of these electrodes for the determination of copper in real samples, and as an indicator electrode for potentiometric titration of Cu2+ ion using EDTA, are reported. The lifetimes of the electrodes were tested over a period of six months to investigate their stability. No significant change in the performance of the sol-gel electrode was observed over this period, but after two months the coated wire copper-selective electrode exhibited a gradual decrease in the slope. The selectivity of the sol-gel electrode was found to be better than that of the coated wire copper-selective electrode. Based on these results, a novel sol-gel copper-selective electrode is proposed for the determination of copper, and applied to real sample assays.

Selective mutism.

Science.gov (United States)

Hua, Alexandra; Major, Nili

2016-02-01

Selective mutism is a disorder in which an individual fails to speak in certain social situations though speaks normally in other settings. Most commonly, this disorder initially manifests when children fail to speak in school. Selective mutism results in significant social and academic impairment in those affected by it. This review will summarize the current understanding of selective mutism with regard to diagnosis, epidemiology, cause, prognosis, and treatment. Studies over the past 20 years have consistently demonstrated a strong relationship between selective mutism and anxiety, most notably social phobia. These findings have led to the recent reclassification of selective mutism as an anxiety disorder in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. In addition to anxiety, several other factors have been implicated in the development of selective mutism, including communication delays and immigration/bilingualism, adding to the complexity of the disorder. In the past few years, several randomized studies have supported the efficacy of psychosocial interventions based on a graduated exposure to situations requiring verbal communication. Less data are available regarding the use of pharmacologic treatment, though there are some studies that suggest a potential benefit. Selective mutism is a disorder that typically emerges in early childhood and is currently conceptualized as an anxiety disorder. The development of selective mutism appears to result from the interplay of a variety of genetic, temperamental, environmental, and developmental factors. Although little has been published about selective mutism in the general pediatric literature, pediatric clinicians are in a position to play an important role in the early diagnosis and treatment of this debilitating condition.

Stability of Stellar Periods in the Hyades and Taurus

Science.gov (United States)

Rebull, Luisa M.; Stauffer, John R.; K2 Clusters Team

2018-06-01

K2 has opened to us the study of high-precision light curves from which we can derive stellar rotation periods. We have presented period distributions for the Pleiades, Praesepe, Upper Sco and Rho Oph. But, how stable are the periods we are deriving from them? Early ground-based work in Orion (Rebull 2001) suggested that, for the youngest stars, about half the stars had sufficiently different spot distributions in two consecutive years such that periods could not be recovered in the second year. However, now that we have K2, precision and diurnal windowing functions are no longer really much of a concern. For a handful of stars in Hyades and Taurus, the K2 spacecraft monitored them for two non-consecutive 70d windows (campaigns 4, 2015 Feb and 13, 2017 Mar). In this poster, we examine whether or not the light curves are similar in the two epochs, and how accurately the same period can be recovered.

Does learning or instinct shape habitat selection?

Directory of Open Access Journals (Sweden)

Scott E Nielsen

Full Text Available Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.

Long-Period Tidal Variations in the Length of Day

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Ray, Richard D.; Erofeeva, Svetlana Y.

2014-01-01

A new model of long-period tidal variations in length of day is developed. The model comprises 80 spectral lines with periods between 18.6 years and 4.7 days, and it consistently includes effects of mantle anelasticity and dynamic ocean tides for all lines. The anelastic properties followWahr and Bergen; experimental confirmation for their results now exists at the fortnightly period, but there remains uncertainty when extrapolating to the longest periods. The ocean modeling builds on recent work with the fortnightly constituent, which suggests that oceanic tidal angular momentum can be reliably predicted at these periods without data assimilation. This is a critical property when modeling most long-period tides, for which little observational data exist. Dynamic ocean effects are quite pronounced at shortest periods as out-of-phase rotation components become nearly as large as in-phase components. The model is tested against a 20 year time series of space geodetic measurements of length of day. The current international standard model is shown to leave significant residual tidal energy, and the new model is found to mostly eliminate that energy, with especially large variance reduction for constituents Sa, Ssa, Mf, and Mt.

Evolution of embryonic developmental period in the marine bird families Alcidae and Spheniscidae: roles for nutrition and predation?

Directory of Open Access Journals (Sweden)

Vos Rutger A

2010-06-01

Full Text Available Abstract Background Nutrition and predation have been considered two primary agents of selection important in the evolution of avian life history traits. The relative importance of these natural selective forces in the evolution of avian embryonic developmental period (EDP remain poorly resolved, perhaps in part because research has tended to focus on a single, high taxonomic-level group of birds: Order Passeriformes. The marine bird families Alcidae (auks and Spheniscidae (penguins exhibit marked variation in EDP, as well as behavioural and ecological traits ultimately linked to EDP. Therefore, auks and penguins provide a unique opportunity to assess the natural selective basis of variation in a key life-history trait at a low taxonomic-level. We used phylogenetic comparative methods to investigate the relative importance of behavioural and ecological factors related to nutrition and predation in the evolution of avian EDP. Results Three behavioural and ecological variables related to nutrition and predation risk (i.e., clutch size, activity pattern, and nesting habits were significant predictors of residual variation in auk and penguin EDP based on models predicting EDP from egg mass. Species with larger clutch sizes, diurnal activity patterns, and open nests had significantly shorter EDPs. Further, EDP was found to be longer among birds which forage in distant offshore waters, relative to those that foraged in near shore waters, in line with our predictions, but not significantly so. Conclusion Current debate has emphasized predation as the primary agent of selection driving avian life history diversification. Our results suggest that both nutrition and predation have been important selective forces in the evolution of auk and penguin EDP, and highlight the importance of considering these questions at lower taxonomic scales. We suggest that further comparative studies on lower taxonomic-level groups will continue to constructively inform the

Forgiveness in the intertestamental period

Directory of Open Access Journals (Sweden)

Sang-Mong Lee

2012-02-01

Full Text Available The article suggests answers to the following questions: what are the characteristics of God�s forgiveness in the intertestamental literature and what connection do these characteristics have with the Old Testament? Important passages in the late Second Temple period that expose the characteristics of God�s forgiveness, such as certain Qumran texts (1QH 12:35�37, 1QH 13:2 and the Damascus Document 14:18�19, the writings of Philo and Josephus, the Apocrypha and the Pseudepigrapha, are investigated for this purpose.

The Periodic Flapping and Breathing of Saturn's Magnetodisk During Equinox

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Sorba, A. M.; Achilleos, N.; Guio, P.; Arridge, C. S.; Dougherty, M. K.; Sergis, N.

2017-12-01

Periodic variations have been observed in many field and particle properties in Saturn's magnetosphere, modulated at a period close to the planetary rotation rate. Magnetic field observations by Cassini's magnetometer instrument suggest that in the outer magnetosphere (beyond 12 Saturn radii) Saturn's current sheet is periodically displaced with respect to the rotational equator, to a first approximation acting as a rotating, tilted disk. This manifests as a `flapping' mode when observed by the spacecraft. Recent studies suggest the magnetosphere also has a `breathing' mode, expanding and contracting with a period close to the planetary rotation rate. We model these two modes in tandem by combining a global, geometrical model of a tilted and rippled current sheet with a local, force-balance model of Saturn's magnetodisk, accounting for the magnetospheric size and hot plasma content. We simulate the breathing behavior by introducing an azimuthal dependence of the system size. We fit Cassini magnetometer data acquired on equatorial orbits from 23 Oct - 17 Dec 2009 (Revs 120-122), close to Saturn equinox, in order that seasonal effects on the current sheet are minimised. We find that our model characterises well the amplitude and phase of the oscillations in the data, for those passes that show clear periodic signatures in the field. In particular, the Bθ (meridional) component can only be characterised when the breathing mode is included. This study introduces calculations for an oscillating boundary under conditions of constant solar wind dynamic pressure, which provide a good basis for understanding the complex relationship between current sheet dynamics and the periodic field perturbations.

Chaos, periodic chaos, and the random-walk problem

International Nuclear Information System (INIS)

Kozak, J.J.; Musho, M.K.; Hatlee, M.D.

1982-01-01

The authors have studied whether numerically generated sequences from the logistic parabola f/sub b/(x) = 4bx(1-x) with b,xelement of[0,1], for values of b above the Feigenbaum critical value b/sub infinity/, are truly chaotic or whether they are periodic but with exceedingly large periods and very long transients. Using the logistic parabola the authors calculate via Monte Carlo simulation the average walk length for trapping on a one-dimensional lattice with a centrosymmetric trap. Comparison with exact results suggests that the only ''truly chaotic'' sequence is the one for which b = 1

Chaos to periodicity and periodicity to chaos by periodic perturbations in the Belousov-Zhabotinsky reaction

International Nuclear Information System (INIS)

Li Qianshu; Zhu Rui

2004-01-01

A three-variable model of the Belousov-Zhabotinsky reaction system subject to external sinusoidal perturbations is investigated by means of frequency spectrum analysis. In the period-1 window of the model, the transitions from periodicity to chaos are observed; in the chaotic window, the transitions from chaos to periodicity are found. The former might be understood by the circle map of two coupled oscillators, and the latter is partly explained by the resonance between the main frequency of the chaos and the frequency of the external periodic perturbations

Apparent directional selection by biased pleiotropic mutation.

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Tanaka, Yoshinari

2010-07-01

Pleiotropic effects of deleterious mutations are considered to be among the factors responsible for genetic constraints on evolution by long-term directional selection acting on a quantitative trait. If pleiotropic phenotypic effects are biased in a particular direction, mutations generate apparent directional selection, which refers to the covariance between fitness and the trait owing to a linear association between the number of mutations possessed by individuals and the genotypic values of the trait. The present analysis has shown how the equilibrium mean value of the trait is determined by a balance between directional selection and biased pleiotropic mutations. Assuming that genes act additively both on the trait and on fitness, the total variance-standardized directional selection gradient was decomposed into apparent and true components. Experimental data on mutation bias from the bristle traits of Drosophila and life history traits of Daphnia suggest that apparent selection explains a small but significant fraction of directional selection pressure that is observed in nature; the data suggest that changes induced in a trait by biased pleiotropic mutation (i.e., by apparent directional selection) are easily compensated for by (true) directional selection.

The effect of posthypnotic suggestion, hypnotic suggestibility, and goal intentions on adherence to medical instructions.

Science.gov (United States)

Carvalho, Claudia; Mazzoni, Giuliana; Kirsch, Irving; Meo, Maria; Santandrea, Maura

2008-04-01

The effects of implementation intentions and posthypnotic suggestion were investigated in 2 studies. In Experiment 1, participants with high levels of hypnotic suggestibility were instructed to take placebo pills as part of an investigation of how to best enhance compliance with medical instruction. In Experiment 2, participants with high, medium, and low levels of hypnotic suggestibility were asked to run in place, take their pulse rate before, and send an e-mail report to the experimenter each day. Experiment 1 revealed enhanced adherence as a function of both implementation intentions and posthypnotic suggestion. Experiment 2 failed to find any significant main effects but found a significant interaction between suggestibility and the effects of posthypnotic suggestion. Posthypnotic suggestion enhanced adherence among high suggestible participants but lowered it among low suggestibles.

A Long-Period Grating Sensor for Wind Turbine Blades

DEFF Research Database (Denmark)

Glavind, Lars

This PhD project concerns the applied research for providing a novel sensor for measurements on wind turbine blades, based on Long-Period Gratings. The idea is based on the utilization of a special asymmetrical optical fibre with Long-Period Gratings for directional sensitive bend sensing...... blade material, where a suitable process and recoating material were investigated. The sensor was implemented and tested on a full scale wind turbine blade placed on a test rig. This first prototype has demonstrated the capability of the sensor for wind turbine blade monitoring, particular...... the possibility to distinguish between the flap- and edge-wise bend directions on the wind turbine blade, providing a selective sensor. The sensor has proven to be very robust and suitable for this application....

Friend suggestion in social network based on user log

Science.gov (United States)

Kaviya, R.; Vanitha, M.; Sumaiya Thaseen, I.; Mangaiyarkarasi, R.

2017-11-01

Simple friend recommendation algorithms such as similarity, popularity and social aspects is the basic requirement to be explored to methodically form high-performance social friend recommendation. Suggestion of friends is followed. No tags of character were followed. In the proposed system, we use an algorithm for network correlation-based social friend recommendation (NC-based SFR).It includes user activities like where one lives and works. A new friend recommendation method, based on network correlation, by considering the effect of different social roles. To model the correlation between different networks, we develop a method that aligns these networks through important feature selection. We consider by preserving the network structure for a more better recommendations so that it significantly improves the accuracy for better friend-recommendation.

Music training relates to the development of neural mechanisms of selective auditory attention.

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Strait, Dana L; Slater, Jessica; O'Connell, Samantha; Kraus, Nina

2015-04-01

Selective attention decreases trial-to-trial variability in cortical auditory-evoked activity. This effect increases over the course of maturation, potentially reflecting the gradual development of selective attention and inhibitory control. Work in adults indicates that music training may alter the development of this neural response characteristic, especially over brain regions associated with executive control: in adult musicians, attention decreases variability in auditory-evoked responses recorded over prefrontal cortex to a greater extent than in nonmusicians. We aimed to determine whether this musician-associated effect emerges during childhood, when selective attention and inhibitory control are under development. We compared cortical auditory-evoked variability to attended and ignored speech streams in musicians and nonmusicians across three age groups: preschoolers, school-aged children and young adults. Results reveal that childhood music training is associated with reduced auditory-evoked response variability recorded over prefrontal cortex during selective auditory attention in school-aged child and adult musicians. Preschoolers, on the other hand, demonstrate no impact of selective attention on cortical response variability and no musician distinctions. This finding is consistent with the gradual emergence of attention during this period and may suggest no pre-existing differences in this attention-related cortical metric between children who undergo music training and those who do not. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Suggestibility under Pressure: Theory of Mind, Executive Function, and Suggestibility in Preschoolers

Science.gov (United States)

Karpinski, Aryn C.; Scullin, Matthew H.

2009-01-01

Eighty preschoolers, ages 3 to 5 years old, completed a 4-phase study in which they experienced a live event and received a pressured, suggestive interview about the event a week later. Children were also administered batteries of theory of mind and executive function tasks, as well as the Video Suggestibility Scale for Children (VSSC), which…

Acute exercise and aerobic fitness influence selective attention during visual search

Science.gov (United States)

Bullock, Tom; Giesbrecht, Barry

2014-01-01

Successful goal directed behavior relies on a human attention system that is flexible and able to adapt to different conditions of physiological stress. However, the effects of physical activity on multiple aspects of selective attention and whether these effects are mediated by aerobic capacity, remains unclear. The aim of the present study was to investigate the effects of a prolonged bout of physical activity on visual search performance and perceptual distraction. Two groups of participants completed a hybrid visual search flanker/response competition task in an initial baseline session and then at 17-min intervals over a 2 h 16 min test period. Participants assigned to the exercise group engaged in steady-state aerobic exercise between completing blocks of the visual task, whereas participants assigned to the control group rested in between blocks. The key result was a correlation between individual differences in aerobic capacity and visual search performance, such that those individuals that were more fit performed the search task more quickly. Critically, this relationship only emerged in the exercise group after the physical activity had begun. The relationship was not present in either group at baseline and never emerged in the control group during the test period, suggesting that under these task demands, aerobic capacity may be an important determinant of visual search performance under physical stress. The results enhance current understanding about the relationship between exercise and cognition, and also inform current models of selective attention. PMID:25426094

Acute exercise and aerobic fitness influence selective attention during visual search.

Science.gov (United States)

Bullock, Tom; Giesbrecht, Barry

2014-01-01

Successful goal directed behavior relies on a human attention system that is flexible and able to adapt to different conditions of physiological stress. However, the effects of physical activity on multiple aspects of selective attention and whether these effects are mediated by aerobic capacity, remains unclear. The aim of the present study was to investigate the effects of a prolonged bout of physical activity on visual search performance and perceptual distraction. Two groups of participants completed a hybrid visual search flanker/response competition task in an initial baseline session and then at 17-min intervals over a 2 h 16 min test period. Participants assigned to the exercise group engaged in steady-state aerobic exercise between completing blocks of the visual task, whereas participants assigned to the control group rested in between blocks. The key result was a correlation between individual differences in aerobic capacity and visual search performance, such that those individuals that were more fit performed the search task more quickly. Critically, this relationship only emerged in the exercise group after the physical activity had begun. The relationship was not present in either group at baseline and never emerged in the control group during the test period, suggesting that under these task demands, aerobic capacity may be an important determinant of visual search performance under physical stress. The results enhance current understanding about the relationship between exercise and cognition, and also inform current models of selective attention.

Acute exercise and aerobic fitness influence selective attention during visual search

Directory of Open Access Journals (Sweden)

Tom eBullock

2014-11-01

Full Text Available Successful goal directed behavior relies on a human attention system that is flexible and able to adapt to different conditions of physiological stress. However, the effects of physical activity on multiple aspects of selective attention and whether these effects are mediated by aerobic capacity, remains unclear. The aim of the present study was to investigate the effects of a prolonged bout of physical activity on visual search performance and perceptual distraction. Two groups of participants completed a hybrid visual search flanker/response competition task in an initial baseline session and then at 17-minute intervals over a 2 hour 16 minute test period. Participants assigned to the exercise group engaged in steady-state aerobic exercise between completing blocks of the visual task, whereas participants assigned to the control group rested in between blocks. The key result was a correlation between individual differences in aerobic capacity and visual search performance, such that those individuals that were more fit performed the search task more quickly. Critically, this relationship only emerged in the exercise group after the physical activity had begun. The relationship was not present in either group at baseline and never emerged in the control group during the test period, suggesting that under these task demands, aerobic capacity may be an important determinant of visual search performance under physical stress. The results enhance current understanding about the relationship between exercise and cognition, and also inform current models of selective attention.

Charged particle periodicity in the Saturnian magnetosphere

International Nuclear Information System (INIS)

Carbary, J.F.; Krimigis, S.M.

1982-01-01

The low energy charged particles (LECP) experiments on the Voyager 1 and 2 spacecraft performed measurements of electrons (approx.22 keV to approx.20 MeV) and ions (approx.28 keV to approx.150 MeV) during the Saturn encounters in 1980 and 1981. Count rate ratios of two of the low energy electron (22 to 35 keV and 183 to 500 keV) and ion (43 to 80 keV and 137 to 215 keV) channels exhibit an approximation 10 hour periodicity in the outer Saturnian magnetosphere beyond the orbit of Titan. Electron ratios vary from approx.50 to approx.300; ion ratios vary from approx.3 to approx.20. Similar but less pronounced periodicities are observed for higher and lower energy electron and ion spectral indices. Three complete cycles were observed during the Voyager 2 outbound portion of the encounter from which were determined an electron ratio period of 10/sup h/21/sup m/ +- 48/sup m/ and an ion ratio period of 9/sup h/49/sup m/ +- 59/sup m/. Using Saturn Kilometric Radiation (SKR) and Saturn Electrostatic Discharge (SED) periods, extrapolation backward from Voyager 2 to Voyager 1 suggests that the periodicities are Saturnian rather than Jovian in nature, and that they persist in phase for time intervals at least as long as 287 days. Ratio minima, or spectral hardenings, occur in the same hemisphere as do auroral brightenings, SKR activity, and spoke enhanement. We interpret the observations as prima facie evidence of an asymmetry in the Saturian magnetic field and the root cause of the observed SKR periodicity

Continental-scale footprint of balancing and positive selection in a small rodent (Microtus arvalis.

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Martin C Fischer

Full Text Available Genetic adaptation to different environmental conditions is expected to lead to large differences between populations at selected loci, thus providing a signature of positive selection. Whereas balancing selection can maintain polymorphisms over long evolutionary periods and even geographic scale, thus leads to low levels of divergence between populations at selected loci. However, little is known about the relative importance of these two selective forces in shaping genomic diversity, partly due to difficulties in recognizing balancing selection in species showing low levels of differentiation. Here we address this problem by studying genomic diversity in the European common vole (Microtus arvalis presenting high levels of differentiation between populations (average F ST = 0.31. We studied 3,839 Amplified Fragment Length Polymorphism (AFLP markers genotyped in 444 individuals from 21 populations distributed across the European continent and hence over different environmental conditions. Our statistical approach to detect markers under selection is based on a Bayesian method specifically developed for AFLP markers, which treats AFLPs as a nearly codominant marker system, and therefore has increased power to detect selection. The high number of screened populations allowed us to detect the signature of balancing selection across a large geographic area. We detected 33 markers potentially under balancing selection, hence strong evidence of stabilizing selection in 21 populations across Europe. However, our analyses identified four-times more markers (138 being under positive selection, and geographical patterns suggest that some of these markers are probably associated with alpine regions, which seem to have environmental conditions that favour adaptation. We conclude that despite favourable conditions in this study for the detection of balancing selection, this evolutionary force seems to play a relatively minor role in shaping the genomic

Visual short-term memory load strengthens selective attention.

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Roper, Zachary J J; Vecera, Shaun P

2014-04-01

Perceptual load theory accounts for many attentional phenomena; however, its mechanism remains elusive because it invokes underspecified attentional resources. Recent dual-task evidence has revealed that a concurrent visual short-term memory (VSTM) load slows visual search and reduces contrast sensitivity, but it is unknown whether a VSTM load also constricts attention in a canonical perceptual load task. If attentional selection draws upon VSTM resources, then distraction effects-which measure attentional "spill-over"-will be reduced as competition for resources increases. Observers performed a low perceptual load flanker task during the delay period of a VSTM change detection task. We observed a reduction of the flanker effect in the perceptual load task as a function of increasing concurrent VSTM load. These findings were not due to perceptual-level interactions between the physical displays of the two tasks. Our findings suggest that perceptual representations of distractor stimuli compete with the maintenance of visual representations held in memory. We conclude that access to VSTM determines the degree of attentional selectivity; when VSTM is not completely taxed, it is more likely for task-irrelevant items to be consolidated and, consequently, affect responses. The "resources" hypothesized by load theory are at least partly mnemonic in nature, due to the strong correspondence they share with VSTM capacity.

Host-Parasite Interactions and Purifying Selection in a Microsporidian Parasite of Honey Bees.

Directory of Open Access Journals (Sweden)

Qiang Huang

Full Text Available To clarify the mechanisms of Nosema ceranae parasitism, we deep-sequenced both honey bee host and parasite mRNAs throughout a complete 6-day infection cycle. By time-series analysis, 1122 parasite genes were significantly differently expressed during the reproduction cycle, clustering into 4 expression patterns. We found reactive mitochondrial oxygen species modulator 1 of the host to be significantly down regulated during the entire infection period. Our data support the hypothesis that apoptosis of honey bee cells was suppressed during infection. We further analyzed genome-wide genetic diversity of this parasite by comparing samples collected from the same site in 2007 and 2013. The number of SNP positions per gene and the proportion of non-synonymous substitutions per gene were significantly reduced over this time period, suggesting purifying selection on the parasite genome and supporting the hypothesis that a subset of N. ceranae strains might be dominating infection.

Selective attention supports working memory maintenance by modulating perceptual processing of distractors.

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Sreenivasan, Kartik K; Jha, Amishi P

2007-01-01

Selective attention has been shown to bias sensory processing in favor of relevant stimuli and against irrelevant or distracting stimuli in perceptual tasks. Increasing evidence suggests that selective attention plays an important role during working memory maintenance, possibly by biasing sensory processing in favor of to-be-remembered items. In the current study, we investigated whether selective attention may also support working memory by biasing processing against irrelevant and potentially distracting information. Event-related potentials (ERPs) were recorded while subjects (n = 22) performed a delayed-recognition task for faces and shoes. The delay period was filled with face or shoe distractors. Behavioral performance was impaired when distractors were congruent with the working memory domain (e.g., face distractor during working memory for faces) relative to when distractors were incongruent with the working memory domain (e.g., face distractor during shoe working memory). If attentional biasing against distractor processing is indeed functionally relevant in supporting working memory maintenance, perceptual processing of distractors is predicted to be attenuated when distractors are more behaviorally intrusive relative to when they are nonintrusive. As such, we predicted that perceptual processing of distracting faces, as measured by the face-sensitive N170 ERP component, would be reduced in the context of congruent (face) working memory relative to incongruent (shoe) working memory. The N170 elicited by distracting faces demonstrated reduced amplitude during congruent versus incongruent working memory. These results suggest that perceptual processing of distracting faces may be attenuated due to attentional biasing against sensory processing of distractors that are most behaviorally intrusive during working memory maintenance.

The Steppengrille (Gryllus spec./assimilis: selective filters and signal mismatch on two time scales.

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Matti Michael Rothbart

Full Text Available In Europe, several species of crickets are available commercially as pet food. Here we investigated the calling song and phonotactic selectivity for sound patterns on the short and long time scales for one such a cricket, Gryllus spec., available as "Gryllus assimilis", the Steppengrille, originally from Ecuador. The calling song consisted of short chirps (2-3 pulses, carrier frequency: 5.0 kHz emitted with a pulse period of 30.2 ms and chirp rate of 0.43 per second. Females exhibited high selectivity on both time scales. The preference for pulse period peaked at 33 ms which was higher then the pulse period produced by males. Two consecutive pulses per chirp at the correct pulse period were already sufficient for positive phonotaxis. The preference for the chirp pattern was limited by selectivity for small chirp duty cycles and for chirp periods between 200 ms and 500 ms. The long chirp period of the songs of males was unattractive to females. On both time scales a mismatch between the song signal of the males and the preference of females was observed. The variability of song parameters as quantified by the coefficient of variation was below 50% for all temporal measures. Hence, there was not a strong indication for directional selection on song parameters by females which could account for the observed mismatch. The divergence of the chirp period and female preference may originate from a founder effect, when the Steppengrille was cultured. Alternatively the mismatch was a result of selection pressures exerted by commercial breeders on low singing activity, to satisfy customers with softly singing crickets. In the latter case the prominent divergence between male song and female preference was the result of domestication and may serve as an example of rapid evolution of song traits in acoustic communication systems.

Regular Topographic Patterning of Karst Depressions Suggests Landscape Self-Organization

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Quintero, C.; Cohen, M. J.

2017-12-01

Thousands of wetland depressions that are commonly host to cypress domes dot the sub-tropical limestone landscape of South Florida. The origin of these depression features has been the topic of debate. Here we build upon the work of previous surveyors of this landscape to analyze the morphology and spatial distribution of depressions on the Big Cypress landscape. We took advantage of the emergence and availability of high resolution Light Direction and Ranging (LiDAR) technology and ArcMap GIS software to analyze the structure and regularity of landscape features with methods unavailable to past surveyors. Six 2.25 km2 LiDAR plots within the preserve were selected for remote analysis and one depression feature within each plot was selected for more intensive sediment and water depth surveying. Depression features on the Big Cypress landscape were found to show strong evidence of regular spatial patterning. Periodicity, a feature of regularly patterned landscapes, is apparent in both Variograms and Radial Spectrum Analyses. Size class distributions of the identified features indicate constrained feature sizes while Average Nearest Neighbor analyses support the inference of dispersed features with non-random spacing. The presence of regular patterning on this landscape strongly implies biotic reinforcement of spatial structure by way of the scale dependent feedback. In characterizing the structure of this wetland landscape we add to the growing body of work dedicated to documenting how water, life and geology may interact to shape the natural landscapes we see today.

Photolysis of Periodate and Periodic Acid in Aqueous Solution

DEFF Research Database (Denmark)

Sehested, Knud; Kläning, U. K.

1978-01-01

The photochemistry of periodate and periodic acid in aqueous solution was studied (i) by quantum yield measurements at low light intensity (ii) by flash photolysis, and (iii) by photolysis of glassy samples at 77 K. The photochemical studies were supplemented with pulse radiolysis studies...... of aqueous periodate solutions and with kinetic studies using stopped-flow technique. In strongly alkaline solution the photodecomposition of periodate proceeds via formation of O– and IVI. At pH solution O3 P is formed in a small...

Utilization of critical periods during development to study the effects of low levels of environmental agents

International Nuclear Information System (INIS)

Russell, L.B.

1980-01-01

Careful definition of critical periods in the development of selected characters can result in experimental systems that may be highly useful in studying risk at low levels of exposure. Three examples are presented. Epidemiological investigations can lose much of their value unless critical periods are known for the end points being studied

Age, period, or birth cohort: What determines demographic differences in seafood consumption?

DEFF Research Database (Denmark)

Scholderer, Joachim; Lund, Eiliv; Trondsen, Torbjørn

Effects of age, period and birth cohort on consumption of fat fish, lean fish and processed fish were estimated based on panel data from the Norwegian Women and Seafood Consumption Study (NOWAC). Cohorts selected for the present analysis were women born between 1951 and 1966. Survey questionnaires...... fish increased between 1996 and 2001, while consumption of lean fish decreased. All three period effects were stable across birth cohorts. Estimation of polynomial contrasts indicated that birth cohort itself had linear effects on consumption, with older generations consuming significantly more fat...... and lean fish, but less processed fish than younger generations. Finally, the effects of cohort and period on consumption of lean and processed fish remained stable when biological age was controlled for, whilst the effect of period on fat fish consumption vanished. Regarding total consumption of fat fish...

Is Hand Selection Modulated by Cognitive-perceptual Load?

Science.gov (United States)

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

?1-Blockers in Men with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Obstruction: Is Silodosin Different?

OpenAIRE

Roehrborn, Claus G.; Cruz, Francisco; Fusco, Ferdinando

2016-01-01

Available ?1-blockers (ABs) have different profiles of receptor selectivity. Silodosin exhibits the highest selectivity for the ?1A adrenergic receptor. This pharmacological feature couples with a singular urodynamic and clinical profile. The magnitude of bladder outlet obstruction improvement in patients receiving silodosin is higher if compared to other ABs. From a clinical point of view, current evidence suggests an advantage in favor of silodosin in terms of nocturia improvement and cardi...

Demographically-Based Evaluation of Genomic Regions under Selection in Domestic Dogs.

Directory of Open Access Journals (Sweden)

Adam H Freedman

2016-03-01

Full Text Available Controlling for background demographic effects is important for accurately identifying loci that have recently undergone positive selection. To date, the effects of demography have not yet been explicitly considered when identifying loci under selection during dog domestication. To investigate positive selection on the dog lineage early in the domestication, we examined patterns of polymorphism in six canid genomes that were previously used to infer a demographic model of dog domestication. Using an inferred demographic model, we computed false discovery rates (FDR and identified 349 outlier regions consistent with positive selection at a low FDR. The signals in the top 100 regions were frequently centered on candidate genes related to brain function and behavior, including LHFPL3, CADM2, GRIK3, SH3GL2, MBP, PDE7B, NTAN1, and GLRA1. These regions contained significant enrichments in behavioral ontology categories. The 3rd top hit, CCRN4L, plays a major role in lipid metabolism, that is supported by additional metabolism related candidates revealed in our scan, including SCP2D1 and PDXC1. Comparing our method to an empirical outlier approach that does not directly account for demography, we found only modest overlaps between the two methods, with 60% of empirical outliers having no overlap with our demography-based outlier detection approach. Demography-aware approaches have lower-rates of false discovery. Our top candidates for selection, in addition to expanding the set of neurobehavioral candidate genes, include genes related to lipid metabolism, suggesting a dietary target of selection that was important during the period when proto-dogs hunted and fed alongside hunter-gatherers.

Comment on 'Approximation for a large-angle simple pendulum period'

International Nuclear Information System (INIS)

Yuan Qingxin; Ding Pei

2009-01-01

In a recent letter, Belendez et al (2009 Eur. J. Phys. 30 L25-8) proposed an alternative of approximation for the period of a simple pendulum suggested earlier by Hite (2005 Phys. Teach. 43 290-2) who set out to improve on the Kidd and Fogg formula (2002 Phys. Teach. 40 81-3). As a response to the approximation scheme, we obtain another analytical approximation for the large-angle pendulum period, which owns the simplicity and accuracy in evaluating the exact period, and moreover, for amplitudes less than 144 deg. the analytical approximate expression is more accurate than others in the literature. (letters and comments)

Subcortical orientation biases explain orientation selectivity of visual cortical cells.

Science.gov (United States)

Vidyasagar, Trichur R; Jayakumar, Jaikishan; Lloyd, Errol; Levichkina, Ekaterina V

2015-04-01

The primary visual cortex of carnivores and primates shows an orderly progression of domains of neurons that are selective to a particular orientation of visual stimuli such as bars and gratings. We recorded from single-thalamic afferent fibers that terminate in these domains to address the issue whether the orientation sensitivity of these fibers could form the basis of the remarkable orientation selectivity exhibited by most cortical cells. We first performed optical imaging of intrinsic signals to obtain a map of orientation domains on the dorsal aspect of the anaesthetized cat's area 17. After confirming using electrophysiological recordings the orientation preferences of single neurons within one or two domains in each animal, we pharmacologically silenced the cortex to leave only the afferent terminals active. The inactivation of cortical neurons was achieved by the superfusion of either kainic acid or muscimol. Responses of single geniculate afferents were then recorded by the use of high impedance electrodes. We found that the orientation preferences of the afferents matched closely with those of the cells in the orientation domains that they terminated in (Pearson's r = 0.633, n = 22, P = 0.002). This suggests a possible subcortical origin for cortical orientation selectivity. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

Comparative analysis of complete mitochondrial genomes suggests that relaxed purifying selection is driving high nonsynonymous evolutionary rate of the NADH2 gene in whitefish (Coregonus ssp.)

DEFF Research Database (Denmark)

Jacobsen, Magnus W.; Rodrigues da Fonseca, Rute Andreia; Bernatchez, Louis

2016-01-01

(Coregonus ssp.) for signals of positive selection. These salmonids show several distinct morphological and ecological differences that may be associated with energetics and therefore potentially positive selection at the mitogenome level. We found that purifying selection and genetic drift were...

Testing increases suggestibility for narrative-based misinformation but reduces suggestibility for question-based misinformation.

Science.gov (United States)

LaPaglia, Jessica A; Chan, Jason C K

2013-01-01

A number of recent studies have found that recalling details of an event following its occurrence can increase people's suggestibility to later presented misinformation. However, several other studies have reported the opposite result, whereby earlier retrieval can reduce subsequent eyewitness suggestibility. In the present study, we investigated whether differences in the way misinformation is presented can modulate the effects of testing on suggestibility. Participants watched a video of a robbery and some were questioned about the event immediately afterwards. Later, participants were exposed to misinformation in a narrative (Experiment 1) or in questions (Experiment 2). Consistent with previous studies, we found that testing increased suggestibility when misinformation was presented via a narrative. Remarkably, when misinformation was presented in questions, testing decreased suggestibility. Copyright © 2013 John Wiley & Sons, Ltd.

The enterprise localization and industrial movement in Teruel (Spain during the period 1992-1998

Directory of Open Access Journals (Sweden)

Juan Carlos Ramon-Solans

2007-07-01

Full Text Available The aim of this text is to demonstrate the nature of the process of industrial change taking place in the Teruel economy during the period 1992-1998. The text forms part of a research project centred on pinpointing the most dynamic sector in Teruel and then analysing them in terms of which factors and variables have most influenced the choice of the location of business in certain areas of Teruel. The most dynamic sectors for the period 1992-1998 were selected from the official Register of Industrial Establishments. A total of 640 companies were created during the period 1992-1998. A sample of 84 new and expanding companies from the fastest growing sectors was then selected. These companies were sent a questionnaire between April and June 2000. The results obtained are analysed and compared to other studies carried out at a national level. Using this data a TOWS or FODA analysis was made of competitive advantages and disadvantages in Teruel in terms of industrial movement, sectorial-productivity structure and location variables.

Vibration isolation design for periodically stiffened shells by the wave finite element method

Science.gov (United States)

Hong, Jie; He, Xueqing; Zhang, Dayi; Zhang, Bing; Ma, Yanhong

2018-04-01

Periodically stiffened shell structures are widely used due to their excellent specific strength, in particular for aeronautical and astronautical components. This paper presents an improved Wave Finite Element Method (FEM) that can be employed to predict the band-gap characteristics of stiffened shell structures efficiently. An aero-engine casing, which is a typical periodically stiffened shell structure, was employed to verify the validation and efficiency of the Wave FEM. Good agreement has been found between the Wave FEM and the classical FEM for different boundary conditions. One effective wave selection method based on the Wave FEM has thus been put forward to filter the radial modes of a shell structure. Furthermore, an optimisation strategy by the combination of the Wave FEM and genetic algorithm was presented for periodically stiffened shell structures. The optimal out-of-plane band gap and the mass of the whole structure can be achieved by the optimisation strategy under an aerodynamic load. Results also indicate that geometric parameters of stiffeners can be properly selected that the out-of-plane vibration attenuates significantly in the frequency band of interest. This study can provide valuable references for designing the band gaps of vibration isolation.

OECD migration, welfare and skill selectivity

DEFF Research Database (Denmark)

Pedersen, Peder; Pytlikova, Mariola; Smith, Nina

into 27 OECD countries over the period of 12 years, 1989-2000. Using a fixed effects panel data model, we analyze the determinants of the migration flows during the latest decade. We study whether there are significant selectivity effects in international migration flows, i.e. whether the countries...

Theory of mind selectively predicts preschoolers' knowledge-based selective word learning.

Science.gov (United States)

Brosseau-Liard, Patricia; Penney, Danielle; Poulin-Dubois, Diane

2015-11-01

Children can selectively attend to various attributes of a model, such as past accuracy or physical strength, to guide their social learning. There is a debate regarding whether a relation exists between theory-of-mind skills and selective learning. We hypothesized that high performance on theory-of-mind tasks would predict preference for learning new words from accurate informants (an epistemic attribute), but not from physically strong informants (a non-epistemic attribute). Three- and 4-year-olds (N = 65) completed two selective learning tasks, and their theory-of-mind abilities were assessed. As expected, performance on a theory-of-mind battery predicted children's preference to learn from more accurate informants but not from physically stronger informants. Results thus suggest that preschoolers with more advanced theory of mind have a better understanding of knowledge and apply that understanding to guide their selection of informants. This work has important implications for research on children's developing social cognition and early learning. © 2015 The British Psychological Society.

Theory of mind selectively predicts preschoolers’ knowledge-based selective word learning

Science.gov (United States)

Brosseau-Liard, Patricia; Penney, Danielle; Poulin-Dubois, Diane

2015-01-01

Children can selectively attend to various attributes of a model, such as past accuracy or physical strength, to guide their social learning. There is a debate regarding whether a relation exists between theory-of-mind skills and selective learning. We hypothesized that high performance on theory-of-mind tasks would predict preference for learning new words from accurate informants (an epistemic attribute), but not from physically strong informants (a non-epistemic attribute). Three- and 4-year-olds (N = 65) completed two selective learning tasks, and their theory of mind abilities were assessed. As expected, performance on a theory-of-mind battery predicted children’s preference to learn from more accurate informants but not from physically stronger informants. Results thus suggest that preschoolers with more advanced theory of mind have a better understanding of knowledge and apply that understanding to guide their selection of informants. This work has important implications for research on children’s developing social cognition and early learning. PMID:26211504

Walkable new urban LEED_Neighborhood-Development (LEED-ND community design and children's physical activity: selection, environmental, or catalyst effects?

Directory of Open Access Journals (Sweden)

Stevens, Robert B

2011-12-01

Full Text Available Abstract Background Interest is growing in physical activity-friendly community designs, but few tests exist of communities explicitly designed to be walkable. We test whether students living in a new urbanist community that is also a pilot LEED_ND (Leadership in Energy and Environmental Design-Neighborhood Development community have greater accelerometer-measured moderate-to-vigorous physical activity (MVPA across particular time periods compared to students from other communities. We test various time/place periods to see if the data best conform to one of three explanations for MVPA. Environmental effects suggest that MVPA occurs when individuals are exposed to activity-friendly settings; selection effects suggest that walkable community residents prefer MVPA, which leads to both their choice of a walkable community and their high levels of MVPA; catalyst effects occur when walking to school creates more MVPA, beyond the school commute, on schooldays but not weekends. Methods Fifth graders (n = 187 were sampled from two schools representing three communities: (1 a walkable community, Daybreak, designed with new urbanist and LEED-ND pilot design standards; (2 a mixed community (where students lived in a less walkable community but attended the walkable school so that part of the route to school was walkable, and (3 a less walkable community. Selection threats were addressed through controlling for parental preferences for their child to walk to school as well as comparing in-school MVPA for the walkable and mixed groups. Results Minutes of MVPA were tested with 3 × 2 (Community by Gender analyses of covariance (ANCOVAs. Community walkability related to more MVPA during the half hour before and after school and, among boys only, more MVPA after school. Boys were more active than girls, except during the half hour after school. Students from the mixed and walkable communities--who attended the same school--had similar in-school MVPA levels, and

Walkable new urban LEED_Neighborhood-Development (LEED-ND) community design and children's physical activity: selection, environmental, or catalyst effects?

Science.gov (United States)

2011-01-01

Background Interest is growing in physical activity-friendly community designs, but few tests exist of communities explicitly designed to be walkable. We test whether students living in a new urbanist community that is also a pilot LEED_ND (Leadership in Energy and Environmental Design-Neighborhood Development) community have greater accelerometer-measured moderate-to-vigorous physical activity (MVPA) across particular time periods compared to students from other communities. We test various time/place periods to see if the data best conform to one of three explanations for MVPA. Environmental effects suggest that MVPA occurs when individuals are exposed to activity-friendly settings; selection effects suggest that walkable community residents prefer MVPA, which leads to both their choice of a walkable community and their high levels of MVPA; catalyst effects occur when walking to school creates more MVPA, beyond the school commute, on schooldays but not weekends. Methods Fifth graders (n = 187) were sampled from two schools representing three communities: (1) a walkable community, Daybreak, designed with new urbanist and LEED-ND pilot design standards; (2) a mixed community (where students lived in a less walkable community but attended the walkable school so that part of the route to school was walkable), and (3) a less walkable community. Selection threats were addressed through controlling for parental preferences for their child to walk to school as well as comparing in-school MVPA for the walkable and mixed groups. Results Minutes of MVPA were tested with 3 × 2 (Community by Gender) analyses of covariance (ANCOVAs). Community walkability related to more MVPA during the half hour before and after school and, among boys only, more MVPA after school. Boys were more active than girls, except during the half hour after school. Students from the mixed and walkable communities--who attended the same school--had similar in-school MVPA levels, and community groups

Performance of Genomic Selection in Mice

OpenAIRE

Legarra, Andrés; Robert-Granié, Christèle; Manfredi, Eduardo; Elsen, Jean-Michel

2008-01-01

Selection plans in plant and animal breeding are driven by genetic evaluation. Recent developments suggest using massive genetic marker information, known as “genomic selection.” There is little evidence of its performance, though. We empirically compared three strategies for selection: (1) use of pedigree and phenotypic information, (2) use of genomewide markers and phenotypic information, and (3) the combination of both. We analyzed four traits from a heterogeneous mouse population (http://...

Adaptive value of phenological traits in stressful environments: predictions based on seed production and laboratory natural selection.

Directory of Open Access Journals (Sweden)

Benjamin Brachi

Full Text Available Phenological traits often show variation within and among natural populations of annual plants. Nevertheless, the adaptive value of post-anthesis traits is seldom tested. In this study, we estimated the adaptive values of pre- and post-anthesis traits in two stressful environments (water stress and interspecific competition, using the selfing annual species Arabidopsis thaliana. By estimating seed production and by performing laboratory natural selection (LNS, we assessed the strength and nature (directional, disruptive and stabilizing of selection acting on phenological traits in A. thaliana under the two tested stress conditions, each with four intensities. Both the type of stress and its intensity affected the strength and nature of selection, as did genetic constraints among phenological traits. Under water stress, both experimental approaches demonstrated directional selection for a shorter life cycle, although bolting time imposes a genetic constraint on the length of the interval between bolting and anthesis. Under interspecific competition, results from the two experimental approaches showed discrepancies. Estimation of seed production predicted directional selection toward early pre-anthesis traits and long post-anthesis periods. In contrast, the LNS approach suggested neutrality for all phenological traits. This study opens questions on adaptation in complex natural environment where many selective pressures act simultaneously.

Selection for rapid embryo development correlates with embryo exposure to maternal androgens among passerine birds.

Science.gov (United States)

Schwabl, Hubert; Palacios, Maria G; Martin, Thomas E

2007-08-01

Greater offspring predation favors evolution of faster development among species. We hypothesized that greater offspring predation exerts selection on mothers to increase levels of anabolic androgens in egg yolks to achieve faster development. Here, we tested whether (1) concentrations of yolk androgens in passerine species were associated with offspring predation and (2) embryo and nestling development rates were associated with yolk androgen concentrations. We examined three androgens that increase in potency along the synthesis pathway: androstenedione (A(4)) to testosterone (T) to 5 alpha -dihydrotestosterone (5 alpha -DHT). Concentrations of none of these steroids were related to clutch size; only A(4) was allometrically related to egg volume. Species that experience greater predation showed higher yolk concentrations of T and 5 alpha -DHT. Higher concentrations of T and particularly 5 alpha -DHT were strongly correlated with faster development during the embryo period and less so during the nestling period. Development rates were most strongly correlated with 5 alpha -DHT, suggesting that potency increases along the androgen synthesis pathway and that effects are mediated by the androgen receptor pathway. These results are consistent with the hypothesis that selection for faster development by time-dependent offspring mortality may be achieved epigenetically by varying embryo exposure to maternal anabolic steroids.

Deepening Sleep by Hypnotic Suggestion

Science.gov (United States)

Cordi, Maren J.; Schlarb, Angelika A.; Rasch, Björn

2014-01-01

Study Objectives: Slow wave sleep (SWS) plays a critical role in body restoration and promotes brain plasticity; however, it markedly declines across the lifespan. Despite its importance, effective tools to increase SWS are rare. Here we tested whether a hypnotic suggestion to “sleep deeper” extends the amount of SWS. Design: Within-subject, placebo-controlled crossover design. Setting: Sleep laboratory at the University of Zurich, Switzerland. Participants: Seventy healthy females 23.27 ± 3.17 y. Intervention: Participants listened to an auditory text with hypnotic suggestions or a control tape before napping for 90 min while high-density electroencephalography was recorded. Measurements and Results: After participants listened to the hypnotic suggestion to “sleep deeper” subsequent SWS was increased by 81% and time spent awake was reduced by 67% (with the amount of SWS or wake in the control condition set to 100%). Other sleep stages remained unaffected. Additionally, slow wave activity was significantly enhanced after hypnotic suggestions. During the hypnotic tape, parietal theta power increases predicted the hypnosis-induced extension of SWS. Additional experiments confirmed that the beneficial effect of hypnotic suggestions on SWS was specific to the hypnotic suggestion and did not occur in low suggestible participants. Conclusions: Our results demonstrate the effectiveness of hypnotic suggestions to specifically increase the amount and duration of slow wave sleep (SWS) in a midday nap using objective measures of sleep in young, healthy, suggestible females. Hypnotic suggestions might be a successful tool with a lower risk of adverse side effects than pharmacological treatments to extend SWS also in clinical and elderly populations. Citation: Cordi MJ, Schlarb AA, Rasch B. Deepening sleep by hypnotic suggestion. SLEEP 2014;37(6):1143-1152. PMID:24882909

Comparing Patterns of Natural Selection across Species Using Selective Signatures

Energy Technology Data Exchange (ETDEWEB)

Shapiro, Jesse; Alm, Eric J.

2007-12-01

Comparing gene expression profiles over many different conditions has led to insights that were not obvious from single experiments. In the same way, comparing patterns of natural selection across a set of ecologically distinct species may extend what can be learned from individual genome-wide surveys. Toward this end, we show how variation in protein evolutionary rates, after correcting for genome-wide effects such as mutation rate and demographic factors, can be used to estimate the level and types of natural selection acting on genes across different species. We identify unusually rapidly and slowly evolving genes, relative to empirically derived genome-wide and gene family-specific background rates for 744 core protein families in 30 c-proteobacterial species. We describe the pattern of fast or slow evolution across species as the"selective signature" of a gene. Selective signatures represent aprofile of selection across species that is predictive of gene function: pairs of genes with correlated selective signatures are more likely to share the same cellular function, and genes in the same pathway can evolve in concert. For example,glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina loihiensis, mirroring an ecological shift in carbon source from sugars to amino acids. In a broader context, our results suggest that the genomic landscape is organized into functional modules even at the level of natural selection, and thus it may be easier than expected to understand the complex evolutionary pressures on a cell.

Comparing Patterns of Natural Selection Across Species Using Selective Signatures

Energy Technology Data Exchange (ETDEWEB)

Alm, Eric J.; Shapiro, B. Jesse; Alm, Eric J.

2007-12-18

Comparing gene expression profiles over many different conditions has led to insights that were not obvious from single experiments. In the same way, comparing patterns of natural selection across a set of ecologically distinct species may extend what can be learned from individual genome-wide surveys. Toward this end, we show how variation in protein evolutionary rates, after correcting for genome-wide effects such as mutation rate and demographic factors, can be used to estimate the level and types of natural selection acting on genes across different species. We identify unusually rapidly and slowly evolving genes, relative to empirically derived genome-wide and gene family-specific background rates for 744 core protein families in 30 gamma-proteobacterial species. We describe the pattern of fast or slow evolution across species as the 'selective signature' of a gene. Selective signatures represent a profile of selection across species that is predictive of gene function: pairs of genes with correlated selective signatures are more likely to share the same cellular function, and genes in the same pathway can evolve in concert. For example, glycolysis and phenylalanine metabolism genes evolve rapidly in Idiomarina loihiensis, mirroring an ecological shift in carbon source from sugars to amino acids. In a broader context, our results suggest that the genomic landscape is organized into functional modules even at the level of natural selection, and thus it may be easier than expected to understand the complex evolutionary pressures on a cell.

Genome-wide scan of gastrointestinal nematode resistance in closed Angus population selected for minimized influence of MHC.

Directory of Open Access Journals (Sweden)

Eui-Soo Kim

Full Text Available Genetic markers associated with parasite indicator traits are ideal targets for study of marker assisted selection aimed at controlling infections that reduce herd use of anthelminthics. For this study, we collected gastrointestinal (GI nematode fecal egg count (FEC data from post-weaning animals of an Angus resource population challenged to a 26 week natural exposure on pasture. In all, data from 487 animals was collected over a 16 year period between 1992 and 2007, most of which were selected for a specific DRB1 allele to reduce the influence of potential allelic variant effects of the MHC locus. A genome-wide association study (GWAS based on BovineSNP50 genotypes revealed six genomic regions located on bovine Chromosomes 3, 5, 8, 15 and 27; which were significantly associated (-log10 p=4.3 with Box-Cox transformed mean FEC (BC-MFEC. DAVID analysis of the genes within the significant genomic regions suggested a correlation between our results and annotation for genes involved in inflammatory response to infection. Furthermore, ROH and selection signature analyses provided strong evidence that the genomic regions associated BC-MFEC have not been affected by local autozygosity or recent experimental selection. These findings provide useful information for parasite resistance prediction for young grazing cattle and suggest new candidate gene targets for development of disease-modifying therapies or future studies of host response to GI parasite infection.

Planet X as the source of the periodic and steady-state flux of short period comets

International Nuclear Information System (INIS)

Matese, J.J.; Whitmire, D.P.

1986-01-01

The cratering and fossil records suggest that impacts on the earth have been modulated with a period of roughly 30 Myr. In the Planet X model, this modulation is the result of the interaction of Planet X with a primordial disk of planetesimals lying beyond the orbit of Neptune. In this paper, observational and theoretical evidence supporting the existence of Planet X and the planetesimal disk is briefly reviewed, and the constraints on the orbit parameters of Planet X and the disk parameters which must be satisfied to ensure consistency with observational limits are discussed

Investigating category- and shape-selective neural processing in ventral and dorsal visual stream under interocular suppression.

Science.gov (United States)

Ludwig, Karin; Kathmann, Norbert; Sterzer, Philipp; Hesselmann, Guido

2015-01-01

Recent behavioral and neuroimaging studies using continuous flash suppression (CFS) have suggested that action-related processing in the dorsal visual stream might be independent of perceptual awareness, in line with the "vision-for-perception" versus "vision-for-action" distinction of the influential dual-stream theory. It remains controversial if evidence suggesting exclusive dorsal stream processing of tool stimuli under CFS can be explained by their elongated shape alone or by action-relevant category representations in dorsal visual cortex. To approach this question, we investigated category- and shape-selective functional magnetic resonance imaging-blood-oxygen level-dependent responses in both visual streams using images of faces and tools. Multivariate pattern analysis showed enhanced decoding of elongated relative to non-elongated tools, both in the ventral and dorsal visual stream. The second aim of our study was to investigate whether the depth of interocular suppression might differentially affect processing in dorsal and ventral areas. However, parametric modulation of suppression depth by varying the CFS mask contrast did not yield any evidence for differential modulation of category-selective activity. Together, our data provide evidence for shape-selective processing under CFS in both dorsal and ventral stream areas and, therefore, do not support the notion that dorsal "vision-for-action" processing is exclusively preserved under interocular suppression. © 2014 Wiley Periodicals, Inc.

Evaluation of scientific periodicals and the Brazilian production of nursing articles.

Science.gov (United States)

Erdmann, Alacoque Lorenzini; Marziale, Maria Helena Palucci; Pedreira, Mavilde da Luz Gonçalves; Lana, Francisco Carlos Félix; Pagliuca, Lorita Marlena Freitag; Padilha, Maria Itayra; Fernandes, Josicelia Dumêt

2009-01-01

This study aimed to identify nursing journals edited in Brazil indexed in the main bibliographic databases in the areas of health and nursing. It also aimed to classify the production of nursing graduate programs in 2007 according to the QUALIS/CAPES criteria used to classify scientific periodicals that disseminate the intellectual production of graduate programs in Brazil. This exploratory study used data from reports and documents available from CAPES to map scientific production and from searching the main international and national indexing databases. The findings from this research can help students, professors and coordinators of graduate programs in several ways: to understand the criteria of classifying periodicals; to be aware of the current production of graduate programs in the area of nursing; and to provide information that authors can use to select periodicals in which to publish their articles.

Applying group selection in upland hardwoods

Science.gov (United States)

Gary w. Miller; H. Clay Smith

1991-01-01

Interest in applying group selection in upland hardwoods has grown in recent years, primarily in response to public opposition to the aesthetic effects of clearcutting. Critics suggest that an uneven-aged silvicultural practice such as group selection might be a suitable compromise--drastically reducing negative visual effects of harvesting trees while continuing to...

On the quasi-periodic nature of magnetopause flux transfer events

International Nuclear Information System (INIS)

Lockwood, M.; Wild, M.N.

1993-01-01

The authors look at the interpretation of magnetopause flux transfer events (FTE), which claims to show that these events are quasi periodic with a mean period of about 8 minutes. FTE are characteristic signatures in the magnetic field observed by satellites in or near the magnetopause. They are mainly observed when the interplanetary magnetic field is southward, as is supported by a wide range of experimental evidence. There are several theoretical models which try to explain these events. The most successful to date is based upon a suggestion made by Saunders and Biernat, et al. This model has the advantage of accounting for some of the ground based observations of these events. It has been suggested that FTE represent bursts of enhanced magnetic reconnection, and may be the dominant mechanism of this solar wind-magnetosphere coupling. The authors also look at the variability of the IMF B z component as a potential source of the periodic FTE. Data from the ISEE 1 and 2 spacecraft taken during 1977 to 1979 were statistically surveyed for this report. The spacecraft crossed the magnetopause more than 172 times, and could observe FTE for typically 1 hr per pass. Data for the IMF came from the IMP8 spacecraft. Little data was available for the period of interest, but for the subsequent phase of the solar cycle there was considerable coverage. The data analysis shows a highly skewed recurrence period, with a mode of 3 min., and a lower and upper decile of 1.5 and 18.5 min. No significant peak is observed at 8 minutes. The shape of the distribution does not lend itself to any natural period of the magnetosphere-ionosphere system. There may be a correlation with the B z component of the IMF, but the correlation suffers most from the variability of the IMF dataset

Experimental removal and elevation of sexual selection: does sexual selection generate manipulative males and resistant females?

Science.gov (United States)

Crudgington, Helen S; Beckerman, Andrew P; Brüstle, Lena; Green, Kathleen; Snook, Rhonda R

2005-05-01

Sexual conflict over reproduction can occur between males and females. In several naturally promiscuous insect species, experimental evolution studies that have enforced monogamy found evidence for sexual conflict. Here, we subjected the naturally promiscuous, sperm-heteromorphic fruit fly Drosophila pseudoobscura to enforced monogamy, standard levels of promiscuity, and elevated opportunities for promiscuity in four replicate lines. We examined the effect of male and female selection history and the proximate effect of variation in male density on female fitness parameters. We found that male density rather than male selection history explained a greater degree of female fecundity, egg hatching success, and productivity. Additionally, females selected under elevated promiscuity had greater fecundity and hatching success than did enforced monogamy females. Selection line males do not differ in their capacity to coerce females to remate, suggesting no divergence in precopulatory manipulative ability. However, these males did vary in their ability to suppress female remating, suggesting postcopulatory manipulation. These results indicate that sexual conflict can be manifested through both the proximate effects of male density and the historical levels of sexual selection and that the sexes respond differentially to these factors and further stress the multifarious channels of sexual communication that contribute to fitness.

Quotas for the select few

International Nuclear Information System (INIS)

Marcan, P.

2007-01-01

Carbon dioxide quotas are no longer a topic only for politicians or Nobel prize winners or a subject of ambitious EU energetic strategies. For the third year they have also been a factor European companies have to take into account when calculating their plans for the forthcoming period. It is a fact that during the first trading period of the emission trading scheme that ends this year, the emission permits represented a big profit making opportunity for Slovak companies. Or compliance with the new rules at least did not cost them anything. But this pleasant position may change in the upcoming 5-year period starting in January. The new emission quota for the 2008 - 2012 period which Brussels has approved for Slovakia will have an impact on individual companies. And so many companies that had a reserve hidden in the original requirement will have to calculate with a certain limitation as far as their free space for ecological manoeuvres is concerned. However, there is still a group of select companies that will get more: power generating companies controlled by the state. (authors)

Flood rich periods, flood poor periods and the need to look beyond instrumental records

Science.gov (United States)

Lane, S. N.

2009-04-01

For many, the later 20th Century and early 21st Century has become synonymous with a growing experience of flood risk. Scientists, politicians and the media have ascribed this to changing climate and there are good hypothetical reasons for human-induced climate change to be impacting upon the magnitude and frequency of extreme weather events. In this paper, I will interrogate this claim more carefully, using the UK's instrumental records of river flow, most of which begin after 1960, but a smaller number of which extend back into the 19th Century. Those records that extent back to the 19th Century suggest that major flood events tend to cluster into periods that are relatively flood rich and relatively flood poor, most notably in larger drainage basins: i.e. there is a clear scale issue. The timing (inset, duration, termination) of these periods varies systematically by region although there is a marked flood poor period for much of the UK during the late 1960s, 1970s and 1980s. It follows that at least some of the current experience of flooding, including why it has taken so many policy-makers and flood victims by surprise, may reflect a transition from a flood poor to a flood rich period, exacerbated by possible climate change impacts. These results point to the need to rethink how we think through what drives flood risk. First, it points to the need to look at some of the fundamental oscillations in core atmospheric drivers, such as the North Atlantic Multidecadal Oscillation, in explaining what drives flood risk. Consideration of precipitation, as opposed to river flow, is more advanced in this respect, and those of us working in rivers need to engage much more thoughtfully with atmospheric scientists. Second, it points to the severe inadequacies in using records of only a few decades duration. Even where these are pooled across adjacent sub-catchments, there is likely to be a severe bias in the estimation of flood return periods when we look at instrumental

The partner selection process : Steps, effectiveness, governance

NARCIS (Netherlands)

Duisters, D.; Duijsters, G.M.; de Man, A.P.

2011-01-01

Selecting the right partner is important for creating value in alliances. Even though prior research suggests that a structured partner selection process increases alliance success, empirical research remains scarce. This paper presents an explorative empirical study that shows that some steps in

The partner selection process : steps, effectiveness, governance

NARCIS (Netherlands)

Duisters, D.; Duysters, G.M.; Man, de A.P.

2011-01-01

Selecting the right partner is important for creating value in alliances. Even though prior research suggests that a structured partner selection process increases alliance success, empirical research remains scarce. This paper presents an explorative empirical study that shows that some steps in

Numerical study of the mode selection in response spectrum analysis-condensed version

International Nuclear Information System (INIS)

Ng, D.S.

1986-01-01

For quality assurance of the dynamic response spectrum analysis, the Nuclear Regulatory Commission (NRC) recommends retaining all modes below the cutoff frequency at which the spectral acceleration (S/sub a/) returns to the peak zero period acceleration (ZPA). It also suggests that modes accounting for at least 90 percent of the structural masses be included in the analysis. A simple frame-type structure is generated as a baseline frame. Then groups of oscillators representing substructure are added onto the frame to study substructure behavior. A base case is established for each frame by including the specific number of modes used. The tests are conducted by incrementing the number of modes in the response spectrum analyses starting with one mode. The structural response of each modal increment is compared with the base case to identify the efficiency of mode selection method. All three methods are then applied to the MFTF-B Axicell Vacuum Vessel. The responses in critical components of the vessel, such as hangers and foundations, will be analyzed to confirm the accuracy of the selected method

The genetic consequences of selection in natural populations.

Science.gov (United States)

Thurman, Timothy J; Barrett, Rowan D H

2016-04-01

The selection coefficient, s, quantifies the strength of selection acting on a genetic variant. Despite this parameter's central importance to population genetic models, until recently we have known relatively little about the value of s in natural populations. With the development of molecular genetic techniques in the late 20th century and the sequencing technologies that followed, biologists are now able to identify genetic variants and directly relate them to organismal fitness. We reviewed the literature for published estimates of natural selection acting at the genetic level and found over 3000 estimates of selection coefficients from 79 studies. Selection coefficients were roughly exponentially distributed, suggesting that the impact of selection at the genetic level is generally weak but can occasionally be quite strong. We used both nonparametric statistics and formal random-effects meta-analysis to determine how selection varies across biological and methodological categories. Selection was stronger when measured over shorter timescales, with the mean magnitude of s greatest for studies that measured selection within a single generation. Our analyses found conflicting trends when considering how selection varies with the genetic scale (e.g., SNPs or haplotypes) at which it is measured, suggesting a need for further research. Besides these quantitative conclusions, we highlight key issues in the calculation, interpretation, and reporting of selection coefficients and provide recommendations for future research. © 2016 John Wiley & Sons Ltd.

Positive periodic solutions of delayed periodic Lotka-Volterra systems

International Nuclear Information System (INIS)

Lin Wei; Chen Tianping

2005-01-01

In this Letter, for a general class of delayed periodic Lotka-Volterra systems, we prove some new results on the existence of positive periodic solutions by Schauder's fixed point theorem. The global asymptotical stability of positive periodic solutions is discussed further, and conditions for exponential convergence are given. The conditions we obtained are weaker than the previously known ones and can be easily reduced to several special cases

Rotation Period Determination for 5143 Heracles

Science.gov (United States)

Pilcher, Frederick; Briggs, John W.; Franco, Lorenzo; Inasaridze, Raguli Ya.; Krugly, Yurij N.; Molotiv, Igor E.; Klinglesmith, Daniel A., III; Pollock, Joe; Pravec, Petr

2012-07-01

The Earth crossing minor planet 5143 Heracles made in late 2011 its closest approach to Earth since discovery. A consortium of observers found a synodic rotation period near 2.706 hours and amplitude increasing from 0.08 ±0.02 magnitudes at phase angle 20 degrees to 0.18 ±0.03 magnitudes at phase angle 87 degrees, with 3 unequal maxima and minima per cycle. Magnitude parameters H = 14.10 ±0.04 and G = 0.08 ±0.02 are found, and the color index V-R = 0.42 ±0.07. For an asteroid of taxonomic class Q, a suggested albedo pv = 0.20 ±0.05 yields estimated diameter D = 4.5 ±0.7 km. Three possible binary events were recorded, but these are insufficient for binary detection to be secure. Retrograde rotation is suggested.

The pulsation mode and period-luminosity relationship of cool variables in globular clusters

International Nuclear Information System (INIS)

Whitelock, P.A.

1986-01-01

The period-luminosity-temperature relationship for globular cluster red and yellow variables is examined. The results suggest that the higher temperature, more metal-deficient cluster variables pulsate in the fundamental mode, while the lower temperature more metal-rich variables pulsate in the first overtone. On the assumption that this is correct, a relationship between fundamental period and bolometric magnitude is derived for cluster variables with observed periods of between 1 and 300 days. (author)

Species selection for smallholder aquaculture

OpenAIRE

Brummett, R.E.

1996-01-01

Systems for selection of species for smallholder aquaculture are presented. These are: food fits; management decisions; and economic criteria. Food fits suggests categorizing pond food resources into a few categories based loosely on the instrinsic traits of food which effect their selectivity by predators. Using management decision techniques, potential polycultures might also be compared with each other and with monoculture. Under economic criteria (and for species known in local markets), ...

Long Term Periodicity Analysis of OJ 287 at Optical V Waveband Jie ...

Indian Academy of Sciences (India)

these spectrum estimation methods in the periodicity analysis on real observational data. We select the blazar OJ 287 for our experiments. In addition to make certain comparative studies, we studied the properties and differences of the methods. We organize the paper as follows: the light curves and data of OJ 287 are ...

[Tarantism in Spain in the eighteen century: latrodectism and suggestion].

Science.gov (United States)

Corral-Corral, I; Corral-Corral, C

2016-10-16

Tarantism is the disease caused by the bite of the tarantula, in which the music tarantella triggers an involuntary dance. It is known in Italy since the sixteenth century. To analyze the tarantism reported in Spain at the end of the eighteenth century, with special attention to its neurological aspects, and to propose its medical and psychopathological explanation. An epidemic of people affected by the tarantula bite occurred in Spain in 1782. Spanish doctors described appropriately the clinical effects, identical to those produced by the bite of the spider black widow (Latrodectus tredecimguttatus), which was at that time identified as a tarantula. The cases reported by Francisco Xavier Cid cured with the involuntary dance triggered by the tarantella, as was described in Italy since the sixteenth century. Our interpretation is that this curative effect of dance in Spain was induced by suggestion. In Spanish patients there were no behavioral disturbances, periodic recurrences or collective involvement as those reported by Italian authors, which suggest an hysterical phenomenon, probably a continuation of the dancing mania of the Middle Age. Tarantism reported in Spain in the eighteenth century includes two different phenomena: the systemic symptoms produced by the tarantula bite, which is actually latrodectism, and the curative effect of the tarantella, explained by suggestion. The psychiatric disturbances, with a hysterical nature, falsely associated to the tarantula bite, observed in Italy, were not present among the Spanish cases of tarantism in the eighteenth century.

Sexually selected traits: a fundamental framework for studies on behavioral epigenetics.

Science.gov (United States)

Jašarević, Eldin; Geary, David C; Rosenfeld, Cheryl S

2012-01-01

Emerging evidence suggests that epigenetic-based mechanisms contribute to various aspects of sex differences in brain and behavior. The major obstacle in establishing and fully understanding this linkage is identifying the traits that are most susceptible to epigenetic modification. We have proposed that sexual selection provides a conceptual framework for identifying such traits. These are traits involved in intrasexual competition for mates and intersexual choice of mating partners and generally entail a combination of male-male competition and female choice. These behaviors are programmed during early embryonic and postnatal development, particularly during the transition from the juvenile to adult periods, by exposure of the brain to steroid hormones, including estradiol and testosterone. We evaluate the evidence that endocrine-disrupting compounds, including bisphenol A, can interfere with the vital epigenetic and gene expression pathways and with the elaboration of sexually selected traits with epigenetic mechanisms presumably governing the expression of these traits. Finally, we review the evidence to suggest that these steroid hormones can induce a variety of epigenetic changes in the brain, including the extent of DNA methylation, histone protein alterations, and even alterations of noncoding RNA, and that many of the changes differ between males and females. Although much previous attention has focused on primary sex differences in reproductive behaviors, such as male mounting and female lordosis, we outline why secondary sex differences related to competition and mate choice might also trace their origins back to steroid-induced epigenetic programming in disparate regions of the brain.

Supplier selection criteria and methods: past, present and future

OpenAIRE

MUKHERJEE, KRISHNENDU

2014-01-01

Sole purpose of supplier selection is not limited to get supply at low cost and at right time. Supplier selection is a strategic decision to fulfil company’s goal for long period of time at low risk. To accomplish this objective companies are moving from reactive buying to proactive buying to give more priority to co-creation of wealth with supplier/s. Considering this issue an attempt has been made in this paper to give systematic review of supplier selection and evaluation process from 2005...

Mutation-selection models of codon substitution and their use to estimate selective strengths on codon usage

DEFF Research Database (Denmark)

Yang, Ziheng; Nielsen, Rasmus

2008-01-01

Current models of codon substitution are formulated at the levels of nucleotide substitution and do not explicitly consider the separate effects of mutation and selection. They are thus incapable of inferring whether mutation or selection is responsible for evolution at silent sites. Here we impl...... codon usage in mammals. Estimates of selection coefficients nevertheless suggest that selection on codon usage is weak and most mutations are nearly neutral. The sensitivity of the analysis on the assumed mutation model is discussed.......Current models of codon substitution are formulated at the levels of nucleotide substitution and do not explicitly consider the separate effects of mutation and selection. They are thus incapable of inferring whether mutation or selection is responsible for evolution at silent sites. Here we...... implement a few population genetics models of codon substitution that explicitly consider mutation bias and natural selection at the DNA level. Selection on codon usage is modeled by introducing codon-fitness parameters, which together with mutation-bias parameters, predict optimal codon frequencies...

Spatio-temporal dynamics of word selection in speech production: Insights from electrocorticography

Directory of Open Access Journals (Sweden)

Stephanie K Ries

2015-04-01

Our results suggest that the posterior inferior LTC is involved in word selection as semantic concepts become available. Posterior medial and left PFC regions may be involved in trial-by-trial top-down control over LTC to help overcome interference caused by semantically-related alternatives in word selection. The single-case result supports this hypothesis and suggests that the posterior medial PFC plays a causal role in resolving this interference in word selection. Lastly, the sensitivity to semantic interference of the post-vocal onset posterior LTC activity suggests the semantic interference effect does not only reflect word selection difficulty but is also present at post-selection stages such as verbal response monitoring. In sum, this study reveals a dynamic network of interacting brain regions that support word selection in language production.

Genome-Wide Association Mapping of Flowering and Ripening Periods in Apple

Directory of Open Access Journals (Sweden)

Jorge Urrestarazu

2017-11-01

Full Text Available Deciphering the genetic control of flowering and ripening periods in apple is essential for breeding cultivars adapted to their growing environments. We implemented a large Genome-Wide Association Study (GWAS at the European level using an association panel of 1,168 different apple genotypes distributed over six locations and phenotyped for these phenological traits. The panel was genotyped at a high-density of SNPs using the Axiom®Apple 480 K SNP array. We ran GWAS with a multi-locus mixed model (MLMM, which handles the putatively confounding effect of significant SNPs elsewhere on the genome. Genomic regions were further investigated to reveal candidate genes responsible for the phenotypic variation. At the whole population level, GWAS retained two SNPs as cofactors on chromosome 9 for flowering period, and six for ripening period (four on chromosome 3, one on chromosome 10 and one on chromosome 16 which, together accounted for 8.9 and 17.2% of the phenotypic variance, respectively. For both traits, SNPs in weak linkage disequilibrium were detected nearby, thus suggesting the existence of allelic heterogeneity. The geographic origins and relationships of apple cultivars accounted for large parts of the phenotypic variation. Variation in genotypic frequency of the SNPs associated with the two traits was connected to the geographic origin of the genotypes (grouped as North+East, West and South Europe, and indicated differential selection in different growing environments. Genes encoding transcription factors containing either NAC or MADS domains were identified as major candidates within the small confidence intervals computed for the associated genomic regions. A strong microsynteny between apple and peach was revealed in all the four confidence interval regions. This study shows how association genetics can unravel the genetic control of important horticultural traits in apple, as well as reduce the confidence intervals of the associated

Selective transcervical tubal recanalisation using DSA

International Nuclear Information System (INIS)

Kelekis, D.; Fezoulidis, I.; Petsas, T.; Tsapalira, A.; Kelekis, N.

1991-01-01

The results of selective transcervical tubal recanalisation by means of a catheter in 20 patients with tubal occlusions are reported and discussed. The advantages of tubal recanalisation under DSA are stressed. In 18 (90%) of the 20 patients treated, it was possible to recanalise at least one tube. Nine of these 18 women (50%) became pregnant during the period of observation, averaging 12 months. Selective transcervical recanalisation of obstructive tubes is a rapid, reliable, cheap and hardly invasive treatment of sterility, when compared with laparoscopy or laparotomy. In the majority of patients it makes surgery unnecessary. (orig.) [de

Periodic flooding restrains local succession of microphytobenthos in floodplain lakes

NARCIS (Netherlands)

van der Grinten, E.; Admiraal, W.; Kraak, M.H.S.

2008-01-01

Periodic flooding of river floodplains and connectivity of floodplain lakes and rivers is suggested to interfere with the succession of microphytobenthos. To analyse this we: 1. studied the impact of flooding on the relationship between irradiance level (depth) and microphytobenthic community

Periodic inventory system in cafeteria using linear programming

Science.gov (United States)

Usop, Mohd Fais; Ishak, Ruzana; Hamdan, Ahmad Ridhuan

2017-11-01

Inventory management is an important factor in running a business. It plays a big role of managing the stock in cafeteria. If the inventories are failed to be managed wisely, it will affect the profit of the cafeteria. Therefore, the purpose of this study is to find the solution of the inventory management in cafeteria. Most of the cafeteria in Malaysia did not manage their stock well. Therefore, this study is to propose a database system of inventory management and to develop the inventory model in cafeteria management. In this study, new database system to improve the management of the stock in a weekly basis will be provided using Linear Programming Model to get the optimal range of the inventory needed for selected categories. Data that were collected by using the Periodic Inventory System at the end of the week within three months period being analyzed by using the Food Stock-take Database. The inventory model was developed from the collected data according to the category of the inventory in the cafeteria. Results showed the effectiveness of using the Periodic Inventory System and will be very helpful to the cafeteria management in organizing the inventory. Moreover, the findings in this study can reduce the cost of operation and increased the profit.

From Periodic Properties to a Periodic Table Arrangement

Science.gov (United States)

Besalú, Emili

2013-01-01

A periodic table is constructed from the consideration of periodic properties and the application of the principal components analysis technique. This procedure is useful for objects classification and data reduction and has been used in the field of chemistry for many applications, such as lanthanides, molecules, or conformers classification.…

Observation of a Short Period Quasi-periodic Pulsation in Solar X-Ray, Microwave, and EUV Emissions

Energy Technology Data Exchange (ETDEWEB)

Kumar, Pankaj; Cho, Kyung-Suk [Korea Astronomy and Space Science Institute (KASI), Daejeon, 305-348 (Korea, Republic of); Nakariakov, Valery M., E-mail: pankaj@kasi.re.kr [Centre for Fusion, Space and Astrophysics, Department of Physics, University of Warwick, CV4 7AL (United Kingdom)

2017-02-10

This paper presents the multiwavelength analysis of a 13 s quasi-periodic pulsation (QPP) observed in hard X-ray (12–300 keV) and microwave (4.9–34 GHz) emissions during a C-class flare that occurred on 2015 September 21. Atmospheric Image Assembly (AIA) 304 and 171 Å images show an emerging loop/flux tube (L1) moving radially outward, which interacts with the preexisting structures within the active region (AR). The QPP was observed during the expansion of and rising motion of L1. The Nobeyama Radioheliograph microwave images in 17/34 GHz channels reveal a single radio source that was co-spatial with a neighboring loop (L2). In addition, using AIA 304 Å images, we detected intensity oscillations in the legs of L2 with a period of about 26 s. A similar oscillation period was observed in the GOES soft X-ray flux derivative. This oscillation period seems to increase with time. We suggest that the observed QPP is most likely generated by the interaction between L2 and L3 observed in the AIA hot channels (131 and 94 Å). The merging speed of loops L2 and L3 was ∼35 km s{sup −1}. L1 was destroyed possibly by its interaction with preexisting structures in the AR, and produced a cool jet with the speed of ∼106–118 km s{sup −1} associated with a narrow CME (∼770 km s{sup −1}). Another mechanism of the QPP in terms of a sausage oscillation of the loop (L2) is also possible.

Haematological and Biochemical Parameters during the Laying Period in Common Pheasant Hens Housed in Enhanced Cages

Directory of Open Access Journals (Sweden)

Petra Hrabčáková

2014-01-01

Full Text Available The development of selected haematological and biochemical parameters during the laying period was monitored in common pheasant hens housed in an enhanced cage system. The cages were enhanced by the addition of two perches and a shelter formed by strips of cloth hanging in the corner of the cage. The results showed significant changes in the haematological and biochemical parameters monitored during egg laying. At the time when laying capacity approached a maximum, a decrease was observed (P<0.05 in haematocrit, erythrocytes, and haemoglobin values, whereas monocytes, eosinophils, the heterophil/lymphocyte ratio, phosphorus, and calcium exhibited an increase (P<0.05. At the end of the laying period, an increase (P<0.05 was recorded in the count of leukocytes, heterophils, lymphocytes and basophils, the heterophil to lymphocyte ratio, and the concentrations of aspartate aminotransferase, cholesterol, phosphorus, and calcium, whereas lower values (P<0.05 were recorded for haematocrit and plasma total protein in comparison with the values of the indicators at the beginning of the laying period. The results provide new information about dynamic changes in selected haematological and biochemical parameters in clinically healthy common pheasant hens during the laying period.

PERSISTENCE IN PERFORMANCE FOR MUTUAL FUNDS IN PERIODS OF CRISIS

Directory of Open Access Journals (Sweden)

Theodoros KARGIDIS

2012-09-01

Full Text Available The study investigates the persistence in performance for a sample of South European funds, domiciled in Portugal, Italy, Greece and Spain. Employing the Sharpe ratio, risk adjusted performance is measured in an attempt to judge the influence of the 2008 crisis and the current debt crisis on funds’ inclination to persist in their previous returns record. Examination period extends from January 2004 to December 2010 incorporating stages of relative stability in the stock and bond markets while also capturing the early stages of the eurozone crisis. We categorize funds as winners and losers in consecutive 6-monthly periods, thus being able to judge persistence in the short run, while our results suggest that the identification of winners and losers could enable us to investigate the possibility to gain investment advantages through this finding. Overall results suggest evidence of persistent results, whether positive or negative, both during the 2008 crisis and the current debt crisis, leading us to deduce that factors leading to performance persistence are not affected by market changes, since medium to long term persistence bypasses any temporary market mischief. This finding could be of use for fund managers aiming at establishing viable investment strategies, at their epicenter being the exploitation of such clues, suggesting persistence in returns. A fund of funds manager employing funds both in equities and fixed income could potentially choose to invest exclusively or more heavily in the winners of previous periods and avoid accordingly poor performers, thus achieving higher returns on average. For this purpose simple investment strategies are employed where we test the outcome of an investment strategy that would invest on fixed income securities by choosing those funds that were winners in the distribution of returns in the previous 6-monthly period, while disinvesting from poor performers and funds switching sides in performance

Perceptual Load Influences Selective Attention across Development

Science.gov (United States)

Couperus, Jane W.

2011-01-01

Research suggests that visual selective attention develops across childhood. However, there is relatively little understanding of the neurological changes that accompany this development, particularly in the context of adult theories of selective attention, such as N. Lavie's (1995) perceptual load theory of attention. This study examined visual…

Mortality in Danish women: age, period and cohort analysis

DEFF Research Database (Denmark)

Lindahl-Jacobsen, Rune

smokers throughout their adult life, suggesting that these smoking habits may be an important factor for their increased mortality. Study aim 3 The analysis of causes of death suggested an increased risk for deaths associated with the respiratory system and from causes traditionally associated....... Conclusion This study has shown that examination of total mortality trends in relation to age, period and cohort is a powerful exploratory tool for understanding changes in mortality and thus life expectancy. The analysis of differences in mortality trends among women in Denmark, Norway and Sweden...

Suggestion, persuasion and work: Psychotherapies in communist Europe.

Science.gov (United States)

Marks, Sarah

2018-01-01

This article traces what recent research and primary sources tell us about psychotherapy in Communist Europe, and how it survived both underground and above the surface. In particular, I will elaborate on the psychotherapeutic techniques that were popular across the different countries and language cultures of the Soviet sphere, with a particular focus upon the Cold War period. This article examines the literature on the mixed fortunes of psychoanalysis and group therapies in the region. More specifically, it focuses upon the therapeutic modalities such as work therapy, suggestion and rational therapy, which gained particular popularity in the Communist countries of Central and Eastern Europe. The latter two approaches had striking similarities with parallel developments in behavioural and cognitive therapies in the West. In part, this was because clinicians on both sides of the 'iron curtain' drew upon shared European traditions from the late nineteenth and early twentieth centuries. Nevertheless, this article argues that in the Soviet sphere, those promoting these approaches appropriated socialist thought as a source of inspiration and justification, or at the very least, as a convenient political shield.

Home range, habitat selection and activity patterns of an arid-zone ...

African Journals Online (AJOL)

All previous behavioural studies of Temminck's ground pangolins (Smutsia temminckii) have focused on populations in mesic regions. We examined home range size, activity periods, habitat selectivity and refuge site selection of 13 individuals over three years in the Kalahari Desert of South Africa, near the western edge of ...

Mixed integer linear programming model for dynamic supplier selection problem considering discounts

Directory of Open Access Journals (Sweden)

Adi Wicaksono Purnawan

2018-01-01

Full Text Available Supplier selection is one of the most important elements in supply chain management. This function involves evaluation of many factors such as, material costs, transportation costs, quality, delays, supplier capacity, storage capacity and others. Each of these factors varies with time, therefore, supplier identified for one period is not necessarily be same for the next period to supply the same product. So, mixed integer linear programming (MILP was developed to overcome the dynamic supplier selection problem (DSSP. In this paper, a mixed integer linear programming model is built to solve the lot-sizing problem with multiple suppliers, multiple periods, multiple products and quantity discounts. The buyer has to make a decision for some products which will be supplied by some suppliers for some periods cosidering by discount. To validate the MILP model with randomly generated data. The model is solved by Lingo 16.

A suggested color scheme for reducing perception-related accidents on construction work sites.

Science.gov (United States)

Yi, June-seong; Kim, Yong-woo; Kim, Ki-aeng; Koo, Bonsang

2012-09-01

Changes in workforce demographics have led to the need for more sophisticated approaches to addressing the safety requirements of the construction industry. Despite extensive research in other industry domains, the construction industry has been passive in exploring the impact of a color scheme; perception-related accidents have been effectively diminished by its implementation. The research demonstrated that the use of appropriate color schemes could improve the actions and psychology of workers on site, thereby increasing their perceptions of potentially dangerous situations. As a preliminary study, the objects selected by rigorous analysis on accident reports were workwear, safety net, gondola, scaffolding, and safety passage. The colors modified on site for temporary facilities were adopted from existing theoretical and empirical research that suggests the use of certain colors and their combinations to improve visibility and conspicuity while minimizing work fatigue. The color schemes were also tested and confirmed through two workshops with workers and managers currently involved in actual projects. The impacts of color schemes suggested in this paper are summarized as follows. First, the color schemes improve the conspicuity of facilities with other on site components, enabling workers to quickly discern and orient themselves in their work environment. Secondly, the color schemes have been selected to minimize the visual work fatigue and monotony that can potentially increase accidents. Copyright © 2011 Elsevier Ltd. All rights reserved.

On the spin period distribution in Be/X-ray binaries

Energy Technology Data Exchange (ETDEWEB)

Cheng, Z.-Q.; Shao, Y.; Li, X.-D., E-mail: lixd@nju.edu.cn [Department of Astronomy, Nanjing University, Nanjing 210093 (China)

2014-05-10

There is a remarkable correlation between the spin periods of the accreting neutron stars (NSs) in Be/X-ray binaries (BeXBs) and their orbital periods. Recently, Knigge et al. showed that the distribution of the spin periods contains two distinct subpopulations peaked at ∼10 s and ∼200 s, respectively, and suggested that they may be related to two types of supernovae for the formation of the NSs, i.e., core-collapse and electron-capture supernovae. Here we propose that the bimodal spin period distribution is likely to be ascribed to different accretion modes of the NSs in BeXBs. When the NS tends to capture material from the warped, outer part of the Be star disk and experiences giant outbursts, a radiatively cooling dominated disk is formed around the NS, which spins up the NS and is responsible for the short-period subpopulation. In BeXBs that are dominated by normal outbursts or are persistent, the accretion flow is advection-dominated or quasi-spherical. The spin-up process is accordingly inefficient, leading to longer periods of the neuron stars. The potential relation between the subpopulations and the supernova mechanism is also discussed.

Sensitive periods in affective development: nonlinear maturation of fear learning.

Science.gov (United States)

Hartley, Catherine A; Lee, Francis S

2015-01-01

At specific maturational stages, neural circuits enter sensitive periods of heightened plasticity, during which the development of both brain and behavior are highly receptive to particular experiential information. A relatively advanced understanding of the regulatory mechanisms governing the initiation, closure, and reinstatement of sensitive period plasticity has emerged from extensive research examining the development of the visual system. In this article, we discuss a large body of work characterizing the pronounced nonlinear changes in fear learning and extinction that occur from childhood through adulthood, and their underlying neural substrates. We draw upon the model of sensitive period regulation within the visual system, and present burgeoning evidence suggesting that parallel mechanisms may regulate the qualitative changes in fear learning across development.

Bounded and Periodic Solutions of Semilinear Impulsive Periodic System on Banach Spaces

Directory of Open Access Journals (Sweden)

Wei W

2008-01-01

Full Text Available Abstract A class of semilinear impulsive periodic system on Banach spaces is considered. First, we introduce the -periodic PC-mild solution of semilinear impulsive periodic system. By virtue of Gronwall lemma with impulse, the estimate on the PC-mild solutions is derived. The continuity and compactness of the new constructed Poincaré operator determined by impulsive evolution operator corresponding to homogenous linear impulsive periodic system are shown. This allows us to apply Horn's fixed-point theorem to prove the existence of -periodic PC-mild solutions when PC-mild solutions are ultimate bounded. This extends the study on periodic solutions of periodic system without impulse to periodic system with impulse on general Banach spaces. At last, an example is given for demonstration.

Does point-of-purchase nutrition labeling influence meal selections? A test in an Army cafeteria.

Science.gov (United States)

Sproul, Allen D; Canter, Deborah D; Schmidt, Jeffrey B

2003-07-01

This study assessed the effectiveness of nutrition labeling on sales of targeted entrees and measured the perceived influence that factors such as taste, quality, appearance, fat content, calorie content, and price had on meal selection behavior within an Army cafeteria. A quasi-experimental design was used to compare targeted entrée sales between a 1-year baseline period and two 30-day postintervention periods, after the placement of entrée nutrition labels. A brief questionnaire, distributed to 149 patrons, measured the perceived influence of the aforementioned factors on selections. Analysis of variance detected no significant differences in sales between baseline and the two intervention periods; the factors of taste and quality were rated most influential to meal selection (p < 0.000). A marketing campaign focusing on the health attributes of targeted entrée items was not successful in boosting sales. Sensory attributes (i.e., taste, quality, and appearance) appear to be more influential to meal selection.

Directional bending wave propagation in periodically perforated plates

DEFF Research Database (Denmark)

Andreassen, Erik; Manktelow, Kevin; Ruzzene, Massimo

2015-01-01

We report on the investigation of wave propagation in a periodically perforated plate. A unit cell with double-C perforations is selected as a test article suitable to investigate two-dimensional dispersion characteristics, group velocities, and internal resonances. A numerical model, formulated...... using Mindlin plate elements, is developed to predict relevant wave characteristics such as dispersion, and group velocity variation as a function of frequency and direction of propagation. Experimental tests are conducted through a scanning laser vibrometer, which provides full wave field information...... for the design of phononic waveguides with directional and internal resonant characteristics....

Dynamics of a broad-area diode laser with lateral-mode-selected long-cavity feedback

DEFF Research Database (Denmark)

Chi, Mingjun; Petersen, Paul Michael

2014-01-01

The temporal dynamics of a broad-area diode laser with lateral-mode-selected long-cavity feedback is studied experimentally. Different dynamics are observed when different lateral modes are selected. When the feedback mirror is aligned perfectly and high-order modes are selected, in most....... When the feedback mirror is aligned non-perfectly, pulse-package oscillation is observed, for the first time to our knowledge, in a diode laser with long-cavity feedback....... of the cases, the output of the laser shows a periodic oscillation corresponding to a single roundtrip external-cavity loop, but the dynamic behavior disappears in some case; when the zero-order lateral-mode is selected, periodic oscillation corresponding to a double roundtrip external-cavity loop is observed...

Metasurface-based angle-selective multichannel acoustic refractor

Science.gov (United States)

Liu, Bingyi; Jiang, Yongyuan

2018-05-01

We theoretically study the angle-selective refractions of an impedance-matched acoustic gradient-index metasurface, which is integrated with a rigid bar array of a deep subwavelength period. An interesting refraction order appears under the all-angle incidence despite the existence of a critical angle, and notably, the odevity of the phase-discretization level apparently selects the transmitted diffraction orders. We utilize the strategy of multilayered media design to realize a three-channel acoustic refractor, which shows good promise for constructing multifunctional diffractive acoustic elements for acoustic communication.

New quasi-periodic waves of the (2+1)-dimensional sine-Gordon system

International Nuclear Information System (INIS)

Hu, H.C.; Lou, S.Y.

2005-01-01

New exact solutions of the well-known (2+1)-dimensional sine-Gordon system are studied by introducing the modified mapping relations between the cubic nonlinear Klein-Gordon and sine-Gordon equations. Two arbitrary functions are included into the Jacobi elliptic function solutions. By proper selections of the arbitrary functions, new quasi-periodic wave solutions are obtained and displayed graphically

High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis

Directory of Open Access Journals (Sweden)

Hector Fernando Arocha-Garza

2017-05-01

Full Text Available The phylum Actinobacteria constitutes one of the largest and anciently divergent phyla within the Bacteria domain. Actinobacterial diversity has been thoroughly researched in various environments due to its unique biotechnological potential. Such studies have focused mostly on soil communities, but more recently marine and extreme environments have also been explored, finding rare taxa and demonstrating dispersal limitation and biogeographic patterns for Streptomyces. To test the distribution of Actinobacteria populations on a small scale, we chose the extremely oligotrophic and biodiverse Cuatro Cienegas Basin (CCB, an endangered oasis in the Chihuahuan desert to assess the diversity and uniqueness of Actinobacteria in the Churince System with a culture-dependent approach over a period of three years, using nine selective media. The 16S rDNA of putative Actinobacteria were sequenced using both bacteria universal and phylum-specific primer pairs. Phylogenetic reconstructions were performed to analyze OTUs clustering and taxonomic identification of the isolates in an evolutionary context, using validated type species of Streptomyces from previously phylogenies as a reference. Rarefaction analysis for total Actinobacteria and for Streptomyces isolates were performed to estimate species’ richness in the intermediate lagoon (IL in the oligotrophic Churince system. A total of 350 morphologically and nutritionally diverse isolates were successfully cultured and characterized as members of the Phylum Actinobacteria. A total of 105 from the total isolates were successfully subcultured, processed for DNA extraction and 16S-rDNA sequenced. All strains belong to the order Actinomycetales, encompassing 11 genera of Actinobacteria; the genus Streptomyces was found to be the most abundant taxa in all the media tested throughout the 3-year sampling period. Phylogenetic analysis of our isolates and another 667 reference strains of the family Streptomycetaceae

High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis

Science.gov (United States)

Arocha-Garza, Hector Fernando; Canales-Del Castillo, Ricardo; Eguiarte, Luis E.; Souza, Valeria

2017-01-01

The phylum Actinobacteria constitutes one of the largest and anciently divergent phyla within the Bacteria domain. Actinobacterial diversity has been thoroughly researched in various environments due to its unique biotechnological potential. Such studies have focused mostly on soil communities, but more recently marine and extreme environments have also been explored, finding rare taxa and demonstrating dispersal limitation and biogeographic patterns for Streptomyces. To test the distribution of Actinobacteria populations on a small scale, we chose the extremely oligotrophic and biodiverse Cuatro Cienegas Basin (CCB), an endangered oasis in the Chihuahuan desert to assess the diversity and uniqueness of Actinobacteria in the Churince System with a culture-dependent approach over a period of three years, using nine selective media. The 16S rDNA of putative Actinobacteria were sequenced using both bacteria universal and phylum-specific primer pairs. Phylogenetic reconstructions were performed to analyze OTUs clustering and taxonomic identification of the isolates in an evolutionary context, using validated type species of Streptomyces from previously phylogenies as a reference. Rarefaction analysis for total Actinobacteria and for Streptomyces isolates were performed to estimate species’ richness in the intermediate lagoon (IL) in the oligotrophic Churince system. A total of 350 morphologically and nutritionally diverse isolates were successfully cultured and characterized as members of the Phylum Actinobacteria. A total of 105 from the total isolates were successfully subcultured, processed for DNA extraction and 16S-rDNA sequenced. All strains belong to the order Actinomycetales, encompassing 11 genera of Actinobacteria; the genus Streptomyces was found to be the most abundant taxa in all the media tested throughout the 3-year sampling period. Phylogenetic analysis of our isolates and another 667 reference strains of the family Streptomycetaceae shows that our

Wheat yield vulnerability: relation to rainfall and suggestions for adaptation

Directory of Open Access Journals (Sweden)

Khalid Tafoughalti

2018-04-01

Full Text Available Wheat production is of paramount importance in the region of Meknes, which is mainly produced under rainfed conditions. It is the dominant cereal, the greater proportion being the soft type. During the past few decades, rainfall flaws have caused a number of cases of droughts. These flaws have seriously affecting wheat production. The main objective of this study is the assessment of rainfall variability at monthly, seasonal and annual scales and to determine their impact on wheat yields. To reduce this impact we suggested some mechanisms of adaptation. We used monthly rainfall records for three decades and wheat yields records of fifteen years. Rainfall variability is assessed utilizing the precipitation concentration index and the variation coefficient. The association between wheat yields and cumulative rainfall amounts of different scales was calculated based on a regression model to evaluate the impact of rainfall on wheat yields. Data analysis shown moderate seasonal and irregular annual rainfall distribution. Yields fluctuated from 210 to 4500 Kg/ha with 52% of coefficient of variation. The correlation results shows that soft wheat and hard wheat are strongly correlated with the period of January to March than with the whole growing-season. While they are adversely correlated with the mid-spring. This investigation concluded that synchronizing appropriate adaptation with the period of January to March was crucial to achieving success yield of wheat.

Stress responsiveness predicts individual variation in mate selectivity.

Science.gov (United States)

Vitousek, Maren N; Romero, L Michael

2013-06-15

Steroid hormones, including glucocorticoids, mediate a variety of behavioral and physiological processes. Circulating hormone concentrations vary substantially within populations, and although hormone titers predict reproductive success in several species, little is known about how individual variation in circulating hormone concentrations is linked with most reproductive behaviors in free-living organisms. Mate choice is an important and often costly component of reproduction that also varies substantially within populations. We examined whether energetically costly mate selection behavior in female Galápagos marine iguanas (Amblyrhynchus cristatus) was associated with individual variation in the concentrations of hormones previously shown to differ between reproductive and non-reproductive females during the breeding season (corticosterone and testosterone). Stress-induced corticosterone levels - which are suppressed in female marine iguanas during reproduction - were individually repeatable throughout the seven-week breeding period. Mate selectivity was strongly predicted by individual variation in stress-induced corticosterone: reproductive females that secreted less corticosterone in response to a standardized stressor assessed more displaying males. Neither baseline corticosterone nor testosterone predicted variation in mate selectivity. Scaled body mass was not significantly associated with mate selectivity, but females that began the breeding period in lower body condition showed a trend towards being less selective about potential mates. These results provide the first evidence that individual variation in the corticosterone stress response is associated with how selective females are in their choice of a mate, an important contributor to fitness in many species. Future research is needed to determine the functional basis of this association, and whether transient acute increases in circulating corticosterone directly mediate mate choice behaviors

LAMMPS Project Report for the Trinity KNL Open Science Period.

Energy Technology Data Exchange (ETDEWEB)

Moore, Stan Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Thompson, Aidan P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wood, Mitchell [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-08-01

LAMMPS is a classical molecular dynamics code (lammps.sandia.gov) used to model materials science problems at Sandia National Laboratories and around the world. LAMMPS was one of three Sandia codes selected to participate in the Trinity KNL (TR2) Open Science period. During this period, three different problems of interest were investigated using LAMMPS. The first was benchmarking KNL performance using different force field models. The second was simulating void collapse in shocked HNS energetic material using an all-atom model. The third was simulating shock propagation through poly-crystalline RDX energetic material using a coarse-grain model, the results of which were used in an ACM Gordon Bell Prize submission. This report describes the results of these simulations, lessons learned, and some hardware issues found on Trinity KNL as part of this work.

Flexural wave attenuation in a sandwich beam with viscoelastic periodic cores

Science.gov (United States)

Guo, Zhiwei; Sheng, Meiping; Pan, Jie

2017-07-01

The flexural-wave attenuation performance of traditional constraint-layer damping in a sandwich beam is improved by using periodic constrained-layer damping (PCLD), where the monolithic viscoelastic core is replaced with two periodically alternating viscoelastic cores. Closed-form solutions of the wave propagation constants of the infinite periodic sandwich beam and the forced response of the corresponding finite sandwich structure are theoretically derived, providing computational support on the analysis of attenuation characteristics. In a sandwich beam with PCLD, the flexural waves can be attenuated by both Bragg scattering effect and damping effect, where the attenuation level is mainly dominated by Bragg scattering in the band-gaps and by damping in the pass-bands. Affected by these two effects, when the parameters of periodic cores are properly selected, a sandwich beam with PCLD can effectively reduce vibrations of much lower frequencies than that with traditional constrained-layer damping. The effects of the parameters of viscoelastic periodic cores on band-gap properties are also discussed, showing that the average attenuation in the desired frequency band can be maximized by tuning the length ratio and core thickness to proper values. The research in this paper could possibly provide useful information for the researches and engineers to design damping structures.

QUASI-STELLAR OBJECT SELECTION ALGORITHM USING TIME VARIABILITY AND MACHINE LEARNING: SELECTION OF 1620 QUASI-STELLAR OBJECT CANDIDATES FROM MACHO LARGE MAGELLANIC CLOUD DATABASE

International Nuclear Information System (INIS)

Kim, Dae-Won; Protopapas, Pavlos; Alcock, Charles; Trichas, Markos; Byun, Yong-Ik; Khardon, Roni

2011-01-01

We present a new quasi-stellar object (QSO) selection algorithm using a Support Vector Machine, a supervised classification method, on a set of extracted time series features including period, amplitude, color, and autocorrelation value. We train a model that separates QSOs from variable stars, non-variable stars, and microlensing events using 58 known QSOs, 1629 variable stars, and 4288 non-variables in the MAssive Compact Halo Object (MACHO) database as a training set. To estimate the efficiency and the accuracy of the model, we perform a cross-validation test using the training set. The test shows that the model correctly identifies ∼80% of known QSOs with a 25% false-positive rate. The majority of the false positives are Be stars. We applied the trained model to the MACHO Large Magellanic Cloud (LMC) data set, which consists of 40 million light curves, and found 1620 QSO candidates. During the selection none of the 33,242 known MACHO variables were misclassified as QSO candidates. In order to estimate the true false-positive rate, we crossmatched the candidates with astronomical catalogs including the Spitzer Surveying the Agents of a Galaxy's Evolution LMC catalog and a few X-ray catalogs. The results further suggest that the majority of the candidates, more than 70%, are QSOs.

Site selection: Past and present

International Nuclear Information System (INIS)

Tilford, N.R.

1994-01-01

Site selection has been going on since the earliest times. The process has evolved through the Industrial Revolution to the present period of exploding population and environmental awareness. Now the work must be done both with increasing sophistication and greater transparency. Modern techniques for site selection have been developed during the last two decades or so, utilizing a teachable body of knowledge and a growing literature. Many firms and individuals have contributed to this growing field. The driving force has been the need for such a process in siting and licensing of critical facilities such as nuclear power plants. A list of crucial, documented steps for identifying social impacts and acceptability are provided. A recent innovation is the self-selection method developed by government. The Superconducting Supercollider serves as an example of this approach. Geological or geologically dependent factors often dominate the process. The role as engineering and environmental geoscientists is to provide responsible leadership, consultation, and communication to the effort

High Arctic plant phenology is determined by snowmelt patterns but duration of phenological periods is fixed

DEFF Research Database (Denmark)

Semenchuk, Philipp R.; Gillespie, Mark A K; Rumpf, Sabine B.

2016-01-01

The duration of specific periods within a plant's life cycle are critical for plant growth and performance. In the High Arctic, the start of many of these phenological periods is determined by snowmelt date, which may change in a changing climate. It has been suggested that the end of these periods...

Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

Energy Technology Data Exchange (ETDEWEB)

Gao, Gongming [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Shen, Nan [Department of Clinical Pharmacy, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Jiang, Xuefeng; Sun, Huiqing [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Xu, Nanwei; Zhou, Dong [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Nong, Luming, E-mail: lumingnong@hotmail.com [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Ren, Kewei, E-mail: keweiren@hotmail.com [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China)

2016-01-15

The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

International Nuclear Information System (INIS)

Gao, Gongming; Shen, Nan; Jiang, Xuefeng; Sun, Huiqing; Xu, Nanwei; Zhou, Dong; Nong, Luming; Ren, Kewei

2016-01-01

The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

Decommissioning strategy selection

International Nuclear Information System (INIS)

Warnecke, E.

2005-01-01

At the end of their useful life nuclear facilities have to be decommissioned. The strategy selection on how to decommission a facility is a highly important decision at the very beginning of decommissioning planning. Basically, a facility may be subject to (a) immediate dismantling; (b) deferred dismantling after a period of ''safe enclosure'' or (c) entombment where a facility is turned into a near surface disposal facility. The first two strategies are normally applied. The third one may be accepted in countries without significant nuclear activities and hence without disposal facilities for radioactive waste. A large number of factors has to be taken into account when a decision on the decommissioning strategy is being made. Many of the factors cannot be quantified. They may be qualitative or subject to public opinion which may change with time. At present, a trend can be observed towards immediate dismantling of nuclear facilities, mainly because it is associated with less uncertainty, less local impact, a better public acceptance, and the availability of operational expertise and know how. A detailed evaluation of the various factors relevant to strategy selection and a few examples showing the situation regarding decommissioning strategy in a number of selected countries are presented in the following article. (orig.)

Nuclear site selection studies

International Nuclear Information System (INIS)

Gharib, A.; Zohoorian Izadpanah, A.A.; Iranmanesh, H.

2000-01-01

It is of special importance, especially from the nuclear safety viewpoint, to select suitable sites for different nuclear structures with the considered future activities. Site selection sometimes involves high costs not necessarily for merely selecting of site but for some preliminary measures to be taken so as the site may have the necessary characteristics. The more suitable the natural characteristics of the site for the considered project, the more successful and efficient the project, the lower the project costs and the longer the project operation period. If so, the project will cause the growth of public culture and sustainable socioeconomic development. This paper is the result of the conclusion of numerous massive reports of this activity in the preliminary phase based on theories, practices and the related safety principles on this ground as well as the application of data and information of the past and a glance to the future. The conception of need for a site for medium structures and nuclear research projects and how to perform this process are presented step by step here with a scientific approach to its selection during the investigations. In this study, it is practically described how the site is selected, by determining and defining the characteristics of research and nuclear projects with medium structures and also its fitting to the optimum site. The discovered sites typically involve the best advantages in technical and economic aspects and no particular contrast with the concerned structures

Hypnotic suggestibility predicts the magnitude of the imaginative word blindness suggestion effect in a non-hypnotic context.

Science.gov (United States)

Parris, Benjamin A; Dienes, Zoltan

2013-09-01

The present study investigated how the magnitude the word blindness suggestion effect on Stroop interference depended on hypnotic suggestibility when given as an imaginative suggestion (i.e. not post-hypnotic suggestion) and under conditions in which hypnosis was not mentioned. Hypnotic suggestibility is shown to be a significant predictor of the magnitude of the imaginative word blindness suggestion effect under these conditions. This is therefore the first study to show a linear relationship between the imaginative word blindness suggestion effect and hypnotic suggestibility across the whole hypnotizability spectrum. The results replicate previous findings showing that highs respond to the word blindness suggestion to a greater extent than lows but extend previous work by showing that the advantage for those higher on the hypnotizability spectrum occurs even in a non-hypnotic context. Negative attitudes about hypnosis may not explain the failure to observe similar effects of the word blindness suggestion in less hypnotizable individuals. Copyright © 2013 Elsevier Inc. All rights reserved.

The long view: Causes of climate change over the instrumental period

Science.gov (United States)

Hegerl, G. C.; Schurer, A. P.; Polson, D.; Iles, C. E.; Bronnimann, S.

2016-12-01

The period of instrumentally recorded data has seen remarkable changes in climate, with periods of rapid warming, and periods of stagnation or cooling. A recent analysis of the observed temperature change from the instrumental record confirms that most of the warming recorded since the middle of the 20rst century has been caused by human influences, but shows large uncertainty in separating greenhouse gas from aerosol response if accounting for model uncertainty. The contribution by natural forcing and internal variability to the recent warming is estimated to be small, but becomes more important when analysing climate change over earlier or shorter time periods. For example, the enigmatic early 20th century warming was a period of strong climate anomalies, including the US dustbowl drought and exceptional heat waves, and pronounced Arctic warming. Attribution results suggests that about half of the global warming 1901-1950 was forced by greenhouse gases increases, with an anomalously strong contribution by climate variability, and contributions by natural forcing. Long term variations in circulation are important for some regional climate anomalies. Precipitation is important for impacts of climate change and precipitation changes are uncertain in models. Analysis of the instrumental record suggests a human influence on mean and heavy precipitation, and supports climate model estimates of the spatial pattern of precipitation sensitivity to warming. Broadly, and particularly over ocean, wet regions are getting wetter and dry regions are getting drier. In conclusion, the historical record provides evidence for a strong response to external forcings, supports climate models, and raises questions about multi-decadal variability.

Sleep does not cause false memories on a story-based test of suggestibility.

Science.gov (United States)

van Rijn, Elaine; Carter, Neil; McMurtrie, Hazel; Willner, Paul; Blagrove, Mark T

2017-07-01

Sleep contributes to the consolidation of memories. This process may involve extracting the gist of learned material at the expense of details. It has thus been proposed that sleep might lead to false memory formation. Previous research examined the effect of sleep on false memory using the Deese-Roediger-McDermott (DRM) paradigm. Mixed results were found, including increases and decreases in false memory after sleep relative to wake. It has been questioned whether DRM false memories occur by the same processes as real-world false memories. Here, the effect of sleep on false memory was investigated using the Gudjonsson Suggestibility Scale. Veridical memory deteriorated after a 12-h period of wake, but not after a 12-h period including a night's sleep. No difference in false memory was found between conditions. Although the literature supports sleep-dependent memory consolidation, the results here call into question extending this to a gist-based false memory effect. Copyright © 2017 Elsevier Inc. All rights reserved.

Variable selection by lasso-type methods

Directory of Open Access Journals (Sweden)

Sohail Chand

2011-09-01

Full Text Available Variable selection is an important property of shrinkage methods. The adaptive lasso is an oracle procedure and can do consistent variable selection. In this paper, we provide an explanation that how use of adaptive weights make it possible for the adaptive lasso to satisfy the necessary and almost sufcient condition for consistent variable selection. We suggest a novel algorithm and give an important result that for the adaptive lasso if predictors are normalised after the introduction of adaptive weights, it makes the adaptive lasso performance identical to the lasso.

Entropy method of measuring and evaluating periodicity of quasi-periodic trajectories

Science.gov (United States)

Ni, Yanshuo; Turitsyn, Konstantin; Baoyin, Hexi; Junfeng, Li

2018-06-01

This paper presents a method for measuring the periodicity of quasi-periodic trajectories by applying discrete Fourier transform (DFT) to the trajectories and analyzing the frequency domain within the concept of entropy. Having introduced the concept of entropy, analytical derivation and numerical results indicate that entropies increase as a logarithmic function of time. Periodic trajectories typically have higher entropies, and trajectories with higher entropies mean the periodicities of the motions are stronger. Theoretical differences between two trajectories expressed as summations of trigonometric functions are also derived analytically. Trajectories in the Henon-Heiles system and the circular restricted three-body problem (CRTBP) are analyzed with the indicator entropy and compared with orthogonal fast Lyapunov indicator (OFLI). The results show that entropy is a better tool for discriminating periodicity in quasiperiodic trajectories than OFLI and can detect periodicity while excluding the spirals that are judged as periodic cases by OFLI. Finally, trajectories in the vicinity of 243 Ida and 6489 Golevka are considered as examples, and the numerical results verify these conclusions. Some trajectories near asteroids look irregular, but their higher entropy values as analyzed by this method serve as evidence of frequency regularity in three directions. Moreover, these results indicate that applying DFT to the trajectories in the vicinity of irregular small bodies and calculating their entropy in the frequency domain provides a useful quantitative analysis method for evaluating orderliness in the periodicity of quasi-periodic trajectories within a given time interval.

Preseason Workload Volume and High-Risk Periods for Noncontact Injury Across Multiple Australian Football League Seasons.

Science.gov (United States)

Colby, Marcus J; Dawson, Brian; Heasman, Jarryd; Rogalski, Brent; Rosenberg, Michael; Lester, Leanne; Peeling, Peter

2017-07-01

Colby, MJ, Dawson, B, Heasman, J, Rogalski, B, Rosenberg, M, Lester, L, and Peeling, P. Preseason workload volume and high-risk periods for noncontact injury across multiple Australian Football League seasons. J Strength Cond Res 31(7): 1821-1829, 2017-The purpose of this study was to assess the association between preseason workloads and noncontact injury risk in Australian football players. Individual player injury data were recorded over 4 full seasons (2012-15) from one professional club. Noncontact injury incidence (per 1,000 "on legs" field training and game hours) was compared across the preseason, precompetition, and in-season phases to determine relative noncontact injury risk. Preseason workloads (global positioning system-derived total distance run and sprint distance) and individual (fixed) injury risk factors (age, previous injury history) were incorporated into the analysis. A generalized estimating equation with a binary logistic function modeled potential risk factors with noncontact injury for selected periods across the annual cycle. Odds ratios were calculated to determine the relative injury risk. The (preseason) precompetition phase (19.1 injuries per 1,000 hours) and (in-season) rounds 12-17 (16.0 injuries per 1,000 hours) resulted in the highest injury incidence. Low cumulative total distances in late preseason (<108 km) and precompetition (76-88 km) periods were associated with significantly (p ≤ 0.05) greater injury risk during the in-season phase. In conclusion, these results suggest players are at the greatest injury risk during the precompetition period, with low preseason cumulative workloads associated with increased in-season injury risk. Therefore, strength and conditioning staff should place particular emphasis on achieving at least moderate training loads during and leading into this phase, where competitive game play is first introduced.

TWO NEW LONG-PERIOD HOT SUBDWARF BINARIES WITH DWARF COMPANIONS

Energy Technology Data Exchange (ETDEWEB)

Barlow, Brad N.; Wade, Richard A. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States); Liss, Sandra E. [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States); Green, Elizabeth M., E-mail: bbarlow@psu.edu [Steward Observatory, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States)

2013-07-01

Hot subdwarf stars with F-K main sequence binary companions have been known for decades, but the first orbital periods for such systems were published just recently. Current observations suggest that most have long periods, on the order of years, and that some are or once were hierarchical triple systems. As part of a survey with the Hobby-Eberly Telescope, we have been monitoring the radial velocities of several composite-spectra binaries since 2005 in order to determine their periods, velocities, and eccentricities. Here we present observations and orbital solutions for two of these systems, PG 1449+653 and PG 1701+359. Similar to the other sdB+F/G/K binaries with solved orbits, their periods are long, 909 and 734 days, respectively, and pose a challenge to current binary population synthesis models of hot subdwarf stars. Intrigued by their relatively large systemic velocities, we also present a kinematical analysis of both targets and find that neither is likely a member of the Galactic thin disk.

TWO NEW LONG-PERIOD HOT SUBDWARF BINARIES WITH DWARF COMPANIONS

International Nuclear Information System (INIS)

Barlow, Brad N.; Wade, Richard A.; Liss, Sandra E.; Green, Elizabeth M.

2013-01-01

Hot subdwarf stars with F-K main sequence binary companions have been known for decades, but the first orbital periods for such systems were published just recently. Current observations suggest that most have long periods, on the order of years, and that some are or once were hierarchical triple systems. As part of a survey with the Hobby-Eberly Telescope, we have been monitoring the radial velocities of several composite-spectra binaries since 2005 in order to determine their periods, velocities, and eccentricities. Here we present observations and orbital solutions for two of these systems, PG 1449+653 and PG 1701+359. Similar to the other sdB+F/G/K binaries with solved orbits, their periods are long, 909 and 734 days, respectively, and pose a challenge to current binary population synthesis models of hot subdwarf stars. Intrigued by their relatively large systemic velocities, we also present a kinematical analysis of both targets and find that neither is likely a member of the Galactic thin disk.

Entrainment to periodic initiation and transition rates in a computational model for gene translation.

Directory of Open Access Journals (Sweden)

Michael Margaliot

Full Text Available Periodic oscillations play an important role in many biomedical systems. Proper functioning of biological systems that respond to periodic signals requires the ability to synchronize with the periodic excitation. For example, the sleep/wake cycle is a manifestation of an internal timing system that synchronizes to the solar day. In the terminology of systems theory, the biological system must entrain or phase-lock to the periodic excitation. Entrainment is also important in synthetic biology. For example, connecting several artificial biological systems that entrain to a common clock may lead to a well-functioning modular system. The cell-cycle is a periodic program that regulates DNA synthesis and cell division. Recent biological studies suggest that cell-cycle related genes entrain to this periodic program at the gene translation level, leading to periodically-varying protein levels of these genes. The ribosome flow model (RFM is a deterministic model obtained via a mean-field approximation of a stochastic model from statistical physics that has been used to model numerous processes including ribosome flow along the mRNA. Here we analyze the RFM under the assumption that the initiation and/or transition rates vary periodically with a common period T. We show that the ribosome distribution profile in the RFM entrains to this periodic excitation. In particular, the protein synthesis pattern converges to a unique periodic solution with period T. To the best of our knowledge, this is the first proof of entrainment in a mathematical model for translation that encapsulates aspects such as initiation and termination rates, ribosomal movement and interactions, and non-homogeneous elongation speeds along the mRNA. Our results support the conjecture that periodic oscillations in tRNA levels and other factors related to the translation process can induce periodic oscillations in protein levels, and may suggest a new approach for re-engineering genetic

Selection, de-selection and progression in German football talent promotion.

Science.gov (United States)

Güllich, Arne

2014-01-01

This study explored to which extent the development of German professional football players is based on early talent identification (TID) and long-term nurture in talent promotion (TP) programmes or on their emergence in the course of repeated procedures of player selection and de-selection in these programmes through childhood and youth. The annual turnover of squad members in national junior teams (2001-2013) and youth elite academies was calculated; national U-team members were followed up with regard to nominations through subsequent seasons and to their success level eventually achieved at senior age; and all current Bundesliga players were analysed retrospectively regarding their earlier involvement in TID/TP programmes. Analyses revealed that the mean annual turnover of squad members was 24.5% (youth academies) and 41.0% (national U-teams), respectively. At any age, the probability of persisting in the programme three years later was <50%. Among current Bundesliga players, the age of recruitment into the TID/TP programme was widely evenly distributed across childhood and youth, respectively. Accordingly, the number of (future) Bundesliga players who were involved in TID/TP was built up continuously through all age categories. The observations suggest that the collective of professional players emerged from repeated procedures of selection and de-selection through childhood and youth rather than from early selection and long-term continuous nurture in TID/TP programmes. The findings are discussed with regard to the uncertainty of TID and of interventions applied to the selected players, and they are related to the individualistic and collectivistic approach in TP.

Children's Memory for Their Mother's Murder: Accuracy, Suggestibility, and Resistance to Suggestion.

Science.gov (United States)

McWilliams, Kelly; Narr, Rachel; Goodman, Gail S; Ruiz, Sandra; Mendoza, Macaria

2013-01-31

From its inception, child eyewitness memory research has been guided by dramatic legal cases that turn on the testimony of children. Decades of scientific research reveal that, under many conditions, children can provide veracious accounts of traumatic experiences. Scientific studies also document factors that lead children to make false statements. In this paper we describe a legal case in which children testified about their mother's murder. We discuss factors that may have influenced the accuracy of the children's eyewitness memory. Children's suggestibility and resistance to suggestion are illustrated. Expert testimony, based on scientific research, can aid the trier of fact when children provide crucial evidence in criminal investigations and courtroom trials about tragic events.

Early evaluation of coronary artery bypass grafts: CT or selective angiography

International Nuclear Information System (INIS)

Wilson, P.C.; Gutierrez, O.; Moss, A.

1984-01-01

A prospective study was performed in 27 patients to compare the value of computed tomography and selective angiography in assessing coronary artery graft patency in the early post-operative period. The sensitivity of CT to graft patency was 85% with no falsely patent determinations. Dynamic CT was not found useful in predicting graft stenosis. There were no complications associated with CT studies, and two related to selective angiography. It is concluded that CT is the procedure of choice for graft evaluation in the early post-operative period; but that angiography is mandatory for the assessment of late symptom recurrence. A review is made of the results described in previous series. (orig.)

Solar wind oscillations with a 1.3 year period

Science.gov (United States)

Richardson, John D.; Paularena, Karolen I.; Belcher, John W.; Lazarus, Alan J.

1994-01-01

The Interplanetary Monitoring Platform 8 (IMP-8) and Voyager 2 spacecraft have recently detected a very strong modulation in the solar wind speed with an approximately 1.3 year period. Combined with evidence from long-term auroral and magnetometer studies, this suggests that fundamental changes in the Sun occur on a roughly 1.3 year time scale.

Vertebrate fauna of the Roman period, migrations period and Medieval period in Vojvodina (Serbia

Directory of Open Access Journals (Sweden)

Radmanović Darko P.

2014-01-01

Full Text Available Based on current published and unpublished research results, a total of 16 vertebrate species members of mammal (Mammalia, bird (Aves and osteichthyes (Osteichthyes classes have been registered at 11 archaeological sites from the Roman Period in Vojvodina. Mammals dominate with 12 species and one genus, birds are present with 3 species, and osteichthyes with one. From the Migration Period, at 9 sites, 22 vertebrate species have been registered, of which 13 species and one genus of mammals, 4 species and one genus of birds, and 5 species from the Osteichthyes class. At 8 sites from the Medieval Period, 16 vertebrate species have been registered. Mammals are the most numerous class with 10 species and one genus, while birds are present with 4 species and one genus. Furthermore, two species of osteichthyes have also been registered.

A STUDY OF THE VARIED AETIOLOGY AND CLINICAL PRESENTATION OF NEW ONSET SEIZURES IN POSTPARTUM PERIOD

Directory of Open Access Journals (Sweden)

Ravindra Kumar Sudarsi

2016-08-01

Full Text Available BACKGROUND Seizures in the postpartum period are the major cause of mortality and morbidity. A variety of neurological disorders causing seizures may be encountered during pregnancy and puerperium. These disorders may be unrelated to pregnancy (e.g. Meningitis or peculiar to pregnancy (e.g. Eclampsia or. Pregnancy may affect the course of the pre-existing neurological disorders such as epilepsy. So, keeping in mind the varied aetiology of postpartum seizures and its response to appropriate treatment, our study has been conducted to find out the most common causes in our setup to guide the optimal therapy. AIM OF THE STUDY To study the varied aetiology and clinical presentation of new onset seizures in the postpartum period over a period of two years. MATERIALS AND METHODS 50 patients who developed first episode of seizures in postpartum period (that is after delivery to 6 weeks admitted to Osmania General Hospital on random selection. All women complaining of new onset seizure with in postpartum period up to 6 weeks. All those women who are known epileptics and who had seizures in the antenatal period were excluded from the study. The selected patients were studied in detail with history and physical examination. RESULTS Different causes for first episode of seizures in postpartum period are enlisted here. Cavernous sinus thrombosis in 17 patients, late postpartum eclampsia accounted for 13 patients, intracranial haemorrhage in 6 patients, ischaemic stroke in 5 patients, posterior reversible encephalopathy syndrome in 4 patients, CNS infections in 6 patients, glioma in 1 patient, viral hepatitis in one patient, idiopathic in 3 patients. CONCLUSIONS Cavernous sinus thrombosis and late postpartum eclampsia constitute the major aetiology of first onset of seizes occurring in the postpartum period.

North–South Asymmetry in Rieger-type Periodicity during Solar Cycles 19–23

International Nuclear Information System (INIS)

Gurgenashvili, Eka; Zaqarashvili, Teimuraz V.; Kukhianidze, Vasil; Oliver, Ramon; Ballester, Jose Luis; Dikpati, Mausumi; McIntosh, Scott W.

2017-01-01

Rieger-type periodicity has been detected in different activity indices over many solar cycles. It was recently shown that the periodicity correlates with solar activity having a shorter period during stronger cycles. Solar activity level is generally asymmetric between northern and southern hemispheres, which could suggest the presence of a similar behavior in the Rieger-type periodicity. We analyze the sunspot area/number and the total magnetic flux data for northern and southern hemispheres during solar cycles 19–23, which had remarkable north–south asymmetry. Using wavelet analysis of sunspot area and number during the north-dominated cycles (19–20), we obtained the periodicity of 160–165 days in the stronger northern hemisphere and 180–190 days in the weaker southern hemisphere. On the other hand, south-dominated cycles (21–23) display the periodicity of 155–160 days in the stronger southern hemisphere and 175–188 days in the weaker northern hemisphere. Therefore, the Rieger-type periodicity has the north–south asymmetry in sunspot area/number data during solar cycles with strong hemispheric asymmetry. We suggest that the periodicity is caused by magnetic Rossby waves in the internal dynamo layer. Using the dispersion relation of magnetic Rossby waves and observed Rieger periodicity, we estimated the magnetic field strength in the layer as 45–49 kG in more active hemispheres (north during cycles 19–20 and south during cycles 21–23) and 33–40 kG in weaker hemispheres. The estimated difference in the hemispheric field strength is around 10 kG, which provides a challenge for dynamo models. Total magnetic flux data during cycles 20–23 reveals no clear north–south asymmetry, which needs to be explained in the future.

North–South Asymmetry in Rieger-type Periodicity during Solar Cycles 19–23

Energy Technology Data Exchange (ETDEWEB)

Gurgenashvili, Eka; Zaqarashvili, Teimuraz V.; Kukhianidze, Vasil [Abastumani Astrophysical Observatory at Ilia State University, Tbilisi, Georgia (United States); Oliver, Ramon; Ballester, Jose Luis [Departament de Física, Universitat de les Illes Balears, E-07122, Palma de Mallorca (Spain); Dikpati, Mausumi; McIntosh, Scott W., E-mail: Eka.gurgenashvili.1@iliauni.edu.ge [High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307 (United States)

2017-08-20

Rieger-type periodicity has been detected in different activity indices over many solar cycles. It was recently shown that the periodicity correlates with solar activity having a shorter period during stronger cycles. Solar activity level is generally asymmetric between northern and southern hemispheres, which could suggest the presence of a similar behavior in the Rieger-type periodicity. We analyze the sunspot area/number and the total magnetic flux data for northern and southern hemispheres during solar cycles 19–23, which had remarkable north–south asymmetry. Using wavelet analysis of sunspot area and number during the north-dominated cycles (19–20), we obtained the periodicity of 160–165 days in the stronger northern hemisphere and 180–190 days in the weaker southern hemisphere. On the other hand, south-dominated cycles (21–23) display the periodicity of 155–160 days in the stronger southern hemisphere and 175–188 days in the weaker northern hemisphere. Therefore, the Rieger-type periodicity has the north–south asymmetry in sunspot area/number data during solar cycles with strong hemispheric asymmetry. We suggest that the periodicity is caused by magnetic Rossby waves in the internal dynamo layer. Using the dispersion relation of magnetic Rossby waves and observed Rieger periodicity, we estimated the magnetic field strength in the layer as 45–49 kG in more active hemispheres (north during cycles 19–20 and south during cycles 21–23) and 33–40 kG in weaker hemispheres. The estimated difference in the hemispheric field strength is around 10 kG, which provides a challenge for dynamo models. Total magnetic flux data during cycles 20–23 reveals no clear north–south asymmetry, which needs to be explained in the future.

Roost selection by Rafinesque’s big-eared bats (Corynorhinus rafinesquii) in a pristine habitat at three spatial scales

Science.gov (United States)

Lucas, Jessica S.; Loeb, Susan C.; Jodice, Patrick G.R.

2015-01-01

Although several studies have described roost use by Rafinesque's big-eared bats (Corynorhinus rafinesquii), few studies have examined roost selection. We examined roost use and selection by Rafinesque's big-eared bat at the tree, stand, and landscape scales during the maternity season in pristine old-growth habitat in the Coastal Plain of South Carolina. We located 43 roosts (14 maternity, 29 solitary) through cavity searches and radio-telemetry. Maternity colonies and solitary individuals selected roosts based on similar characteristics. The best model explaining roost selection by all bats included tree and stand characteristics; landscape factors had little influence on roost use. Bats selected large diameter trees in areas with a high density of trees with cavities in the surrounding area. Most roosts (67.4%) were in water tupelo (Nyssa aquatica) in semi-permanently flooded and saturated areas. Half of maternity roost cavities had upper bole openings whereas only 25.8% of solitary roosts had upper bole openings. Bats that roosted with maternity groups stayed in roosts for significantly shorter periods of time (1.3 ± 0.1 days) and used significantly more roost trees (5.0 ± 0.6 roosts) than adult males (3.8 ± 1.10 days, 2.3 ± 0.4 roosts, respectively). Maternity colony use of cavities with upper bole openings and shorter residency times suggest that predator avoidance may have been an important factor governing roosting behavior of maternity colonies in this area. Our results suggest that retention of large diameter, hollow trees in wetland areas will benefit Rafinesque's big-eared bat individuals and maternity colonies in this area.

Grass species selection patterns on rotationally-grazed Dohne ...

African Journals Online (AJOL)

Herbaceous species preference was studied during autumn and winter periods of occupation, on rotationally-grazed Dohne Sourveld, at four different stocking rates. Reports on species selection by cattle and sheep grazing together. Illustrates with graphsLanguage: English. Keywords: Grass species; Herbage availibility; ...

Commuting periodic operators and the periodic Wigner function

International Nuclear Information System (INIS)

Zak, J

2004-01-01

Commuting periodic operators (CPO) depending on the coordinate x-hat and the momentum p-hat operators are defined. The CPO are functions of the two basic commuting operators exp(i x-hat 2π/a) and exp(i/h p-hat a), with a being an arbitrary constant. A periodic Wigner function (PWF) w(x, p) is defined and it is shown that it is applicable in a normal expectation value calculation to the CPO, as done in the original Wigner paper. Moreover, this PWF is non-negative everywhere, and it can therefore be interpreted as an actual probability distribution. The PWF w(x, p) is shown to be given as an expectation value of the periodic Dirac delta function in the phase plane. (letter to the editor)

Physically-insightful equivalent circuit models for electromagnetic periodic structures

Science.gov (United States)

Mesa, F.; Rodríguez-Berral, R.; Medina, F.

2018-02-01

In this presentation it will be discussed how to obtain analytical or quasi-analytical equivalent circuits to deal with periodic structures such as frequency selective surfaces and/or metasurfaces. Both the topology and the values of the involved elements of these circuits are obtained from a basic rationale to solve the corresponding integral equation. This procedure, besides providing a very efficient analysis/design tool, allows for a good physical insight into the operating mechanisms of the structure in contrast with the almost blind numerical scheme of commercial simulators.

Time-periodic solutions of the Benjamin-Ono equation

Energy Technology Data Exchange (ETDEWEB)

Ambrose , D.M.; Wilkening, Jon

2008-04-01

We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations.

Time-periodic solutions of the Benjamin-Ono equation

International Nuclear Information System (INIS)

Ambrose, D.M.; Wilkening, Jon

2008-01-01

We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations

Forward Period Analysis Method of the Periodic Hamiltonian System.

Directory of Open Access Journals (Sweden)

Pengfei Wang

Full Text Available Using the forward period analysis (FPA, we obtain the period of a Morse oscillator and mathematical pendulum system, with the accuracy of 100 significant digits. From these results, the long-term [0, 1060] (time unit solutions, ranging from the Planck time to the age of the universe, are computed reliably and quickly with a parallel multiple-precision Taylor series (PMT scheme. The application of FPA to periodic systems can greatly reduce the computation time of long-term reliable simulations. This scheme provides an efficient way to generate reference solutions, against which long-term simulations using other schemes can be tested.

Quasi-periodic fluctuations of atmospheric pressure and cosmic rays observed in the stratosphere

International Nuclear Information System (INIS)

Kodama, Masahiro; Abe, Toshiaki; Sakai, Takasuke; Kato, Masato; Kogami, Shinichi.

1976-01-01

Quasi-periodicities of barometric pressure and cosmic ray intensity, with 5.5-minute period and one hour persistency, have been observed by means of a high-precision barometer and a large plastic scintillation counter in a balloon at an altitude of --18 km over the Pacific Ocean. From characteristics of such short period fluctuations, it is suggested that the observed pressure fluctuation may possibly be caused by the internal atmospheric gravity wave whose amplitude and wave length are --30 m and --30 km respectively. (auth.)

Perihelion asymmetry in the photometric parameters of long-period comets at large heliocentric distances

International Nuclear Information System (INIS)

Svoren, J.

1982-01-01

The present statistical analysis is based on a sample of long-period comets selected according to two criteria: (1) availability of photometric observations made at large distances from the Sun and covering an orbital arc long enough for a reliable determination of the photometric parameters, and (2) availability of a well determined orbit making it possible to classify the comet as new or old in Oort's (1950) sense. The selection was confined to comets with nearly parabolic orbits. 67 objects were found to satisfy the selection criteria. Photometric data referring to heliocentric distances of r > 2.5 AU were only used, yielding a total of 2,842 individual estimates and measurements. (Auth.)

Directional and balancing selection in human beta-defensins.

Science.gov (United States)

Hollox, Edward J; Armour, John A L

2008-04-16

In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93), is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

Instructional Suggestions Supporting Science Learning in Digital Environments Based on a Review of Eye-Tracking Studies

Science.gov (United States)

Yang, Fang-Ying; Tsai, Meng-Jung; Chiou, Guo-Li; Lee, Silvia Wen-Yu; Chang, Cheng-Chieh; Chen, Li-Ling

2018-01-01

The main purpose of this study was to provide instructional suggestions for supporting science learning in digital environments based on a review of eye tracking studies in e-learning related areas. Thirty-three eye-tracking studies from 2005 to 2014 were selected from the Social Science Citation Index (SSCI) database for review. Through a…

Estimation of pre-meiotic DNA synthesis period in the dog spermatozoa

International Nuclear Information System (INIS)

Ghosal, S.K.; Bandyopadhyay, T.; De, S.; Beauregard, L.J.

1976-01-01

About 10 μCi of 3 H-thymidine was injected into each of 4 arbitarary sites in each testis of 6 dogs. Biopsies were taken at 4-hour intervals coverning a period from 20.0 to 22.2 days post-injection. Kinetics of labelled spermatocytes was followed employing Kodak NTB-3 emulsion to conventionally prepared air-dried slides. The technique for calculating pre-meiosis DNA synthesis duration is same as that for estimating S period in mitotic cells. Current investigation suggests that the mean duration of pre-meiotic S period of Canine spermatocytes is 20.4 hrs as compared to 29 and 40 hrs in spermatocytes of mouse and golden hamster respectively. (author)

Separating the effects of age, period and birth cohort on seafood consumption in Norway

DEFF Research Database (Denmark)

Scholderer, Joachim; Trondsen, Torbjørn; Lund, Eiliv

Effects of age, period and birth cohort on consumption of fat fish, lean fish and processed fish were estimated based on panel data from the Norwegian Women and Seafood Consumption Study (NOWAC). Cohorts selected for the present analysis were women born between 1951 and 1966. Survey questionnaires...... fish increased between 1996 and 2001, while consumption of lean fish decreased. All three period effects were stable across birth cohorts. Estimation of polynomial contrasts indicated that birth cohort itself had linear effects on consumption, with older generations consuming significantly more fat...... and lean fish, but less processed fish than younger generations. Finally, the effects of cohort and period on consumption of lean and processed fish remained stable when biological age was controlled for, whilst the effect of period on fat fish consumption vanished. Regarding total consumption of fat fish...

Selection statements of the Federal Government of Germany of the 8th legislative period. Pt. 2

International Nuclear Information System (INIS)

Mayer, G.

1980-02-01

This selection of opinions of the Government of the Federal Republic of Germany covers the total fuel circuit. It is classified in a lucid index and the complete texts of the questioning of the Bundestag and the answers given by the Federal Government. Questions and answers are put directly one after the other to obtain a better view. (Publications of the Bundestag and plenary minutes). (HP) [de

A practical alternative to single tree selection?

Science.gov (United States)

Gary W. Miller; H. Clay Smith

1993-01-01

When landowners want to develop and maintain an uneven-aged tree structure in eastern hardwood stands, single-tree selection often is suggested as the only advisable, long-term partial regeneration harvest method. Single-tree selection is preferred because it provides a means for improving quality and controlling stocking of the residual stand necessary for sustained...

Reproductive ethogram and mate selection in captive wild Senegalese sole (Solea senegalensis)

Energy Technology Data Exchange (ETDEWEB)

Carazo, I.; Chereguini, O.; Martín, I.; Huntingford, F.; Duncan, N.

2016-07-01

Senegalese e sole (Solea senegalensis) have a high potential for aquaculture that is hampered by reproductive behavioural problems. These problems result in limited breeder participation in spawning. The present study provided an ethogram and described mate selection and spawning of captive wild Senegalese sole. Two tanks of breeders were studied that had 29 and 25 breeders (mean weight = 1.6 ± 0.1 kg). The behaviour was studied during 20 periods of 24 hours: 10 periods where spawning events were recorded and 10 control periods without spawning events. Periods where spawning occurred had three times more locomotor activity than periods without spawning. Two distinct behaviours, termed the “following” behaviour and the “coupled swim”, were only observed during periods with spawning. The courtship sequence (n=12) began with males predominantly involved in “following” behaviours, whilst females remained mainly stationary on the bottom of the tank. Males rested on the females and encouraged the females to begin swimming. When the female began to swim the male swam under the female and the pair made a “coupled swim” to the surface to release gametes. Gamete release was strictly in pairs of one male with one female. Failed “coupled swims” without gamete release were 5.6 times more frequent than successful “coupled swims”. Mate selection was evident as the sole engaged in: paired spawning, males displayed to females, males encouraged females to spawn and females accepted or rejected the male’s advances. The mate selection process provided the opportunity for fish to dominate the spawning and also demonstrated how fish were excluded from spawning.

Reproductive ethogram and mate selection in captive wild Senegalese sole (Solea senegalensis)

International Nuclear Information System (INIS)

Carazo, I.; Chereguini, O.; Martín, I.; Huntingford, F.; Duncan, N.

2016-01-01

Senegalese e sole (Solea senegalensis) have a high potential for aquaculture that is hampered by reproductive behavioural problems. These problems result in limited breeder participation in spawning. The present study provided an ethogram and described mate selection and spawning of captive wild Senegalese sole. Two tanks of breeders were studied that had 29 and 25 breeders (mean weight = 1.6 ± 0.1 kg). The behaviour was studied during 20 periods of 24 hours: 10 periods where spawning events were recorded and 10 control periods without spawning events. Periods where spawning occurred had three times more locomotor activity than periods without spawning. Two distinct behaviours, termed the “following” behaviour and the “coupled swim”, were only observed during periods with spawning. The courtship sequence (n=12) began with males predominantly involved in “following” behaviours, whilst females remained mainly stationary on the bottom of the tank. Males rested on the females and encouraged the females to begin swimming. When the female began to swim the male swam under the female and the pair made a “coupled swim” to the surface to release gametes. Gamete release was strictly in pairs of one male with one female. Failed “coupled swims” without gamete release were 5.6 times more frequent than successful “coupled swims”. Mate selection was evident as the sole engaged in: paired spawning, males displayed to females, males encouraged females to spawn and females accepted or rejected the male’s advances. The mate selection process provided the opportunity for fish to dominate the spawning and also demonstrated how fish were excluded from spawning.

Weather types in Sosnowiec (Poland during the period 1999-2013

Directory of Open Access Journals (Sweden)

Dobrowolska Ksenia

2014-09-01

Full Text Available The study presents the structure of weather types for the city of Sosnowiec during the period 1999-2013. The analysis was carried out on the basis of daily thermal data (the average daily air temperature, the minimum and maximum daily air temperature, cloudiness and precipitation. The data was obtained from a meteorological station belonging to the Department of Climatology at the Faculty of Earth Sciences at the University of Silesia. Weather types were established according to weather type classification after Woś (2010. 48 weather types were specified on the basis of a combination of 3 selected meteorological elements (temperature, cloudiness, precipitation. The number of days in the year and the frequency of particular thermal weather types, weather subtype, weather classes and weather types were characterized, and the changeability of weather types was analyzed. Furthermore, sequences of days with specific weather types were described. The analysis conducted has lead to the conclusion that, during the research period, the weather structure for the city of Sosnowiec was characterized by a great number of weather types observed, with relatively low frequency of occurrence. Weather throughout the year was dominated by warm weather types (3--, 2--, 2--, with weather marked as 310 – very warm, moderately cloudy, without precipitation (12.9% recorded as the most frequent, followed by 221 – moderately warm, very cloudy, with precipitation (11.6%, and 210 – moderately warm, moderately cloudy, without precipitation (11.4%as the least frequent one. A diversification in the number of particular classification units in consecutive years of the examined 15-year period does not display significant variability. Short sequences of 2 and 3 days dominated the selected sequences of specific weather types.

A neural circuit transforming temporal periodicity information into a rate-based representation in the mammalian auditory system

DEFF Research Database (Denmark)

Dicke, Ulrike; Ewert, Stephan D.; Dau, Torsten

2007-01-01

Periodic amplitude modulations AMs of an acoustic stimulus are presumed to be encoded in temporal activity patterns of neurons in the cochlear nucleus. Physiological recordings indicate that this temporal AM code is transformed into a rate-based periodicity code along the ascending auditory pathw...... accounts for the encoding of AM depth over a large dynamic range and for modulation frequency selective processing of complex sounds....

Credibilistic multi-period portfolio optimization based on scenario tree

Science.gov (United States)

Mohebbi, Negin; Najafi, Amir Abbas

2018-02-01

In this paper, we consider a multi-period fuzzy portfolio optimization model with considering transaction costs and the possibility of risk-free investment. We formulate a bi-objective mean-VaR portfolio selection model based on the integration of fuzzy credibility theory and scenario tree in order to dealing with the markets uncertainty. The scenario tree is also a proper method for modeling multi-period portfolio problems since the length and continuity of their horizon. We take the return and risk as well cardinality, threshold, class, and liquidity constraints into consideration for further compliance of the model with reality. Then, an interactive dynamic programming method, which is based on a two-phase fuzzy interactive approach, is employed to solve the proposed model. In order to verify the proposed model, we present an empirical application in NYSE under different circumstances. The results show that the consideration of data uncertainty and other real-world assumptions lead to more practical and efficient solutions.

Selectively reflective transparent sheets

Science.gov (United States)

Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

2015-08-01

We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

An analysis of project selection and assignment criteria of danish tenders in europe

DEFF Research Database (Denmark)

Larsen, Jesper Kranker; Ussing, Lene Faber; Brunø, Thomas Ditlev

2013-01-01

, and 3/ any significant difference between the use of selection and assignment criteria in Danish public construction projects. The study uses a quantitative research approach where 157 Danish public tender cases were selected from the European Tenders Electronic Daily database between the period...

The Periodic Pyramid

Science.gov (United States)

Hennigan, Jennifer N.; Grubbs, W. Tandy

2013-01-01

The chemical elements present in the modern periodic table are arranged in terms of atomic numbers and chemical periodicity. Periodicity arises from quantum mechanical limitations on how many electrons can occupy various shells and subshells of an atom. The shell model of the atom predicts that a maximum of 2, 8, 18, and 32 electrons can occupy…

Fast periodic stimulation (FPS): a highly effective approach in fMRI brain mapping.

Science.gov (United States)

Gao, Xiaoqing; Gentile, Francesco; Rossion, Bruno

2018-03-03

Defining the neural basis of perceptual categorization in a rapidly changing natural environment with low-temporal resolution methods such as functional magnetic resonance imaging (fMRI) is challenging. Here, we present a novel fast periodic stimulation (FPS)-fMRI approach to define face-selective brain regions with natural images. Human observers are presented with a dynamic stream of widely variable natural object images alternating at a fast rate (6 images/s). Every 9 s, a short burst of variable face images contrasting with object images in pairs induces an objective face-selective neural response at 0.111 Hz. A model-free Fourier analysis achieves a twofold increase in signal-to-noise ratio compared to a conventional block-design approach with identical stimuli and scanning duration, allowing to derive a comprehensive map of face-selective areas in the ventral occipito-temporal cortex, including the anterior temporal lobe (ATL), in all individual brains. Critically, periodicity of the desired category contrast and random variability among widely diverse images effectively eliminates the contribution of low-level visual cues, and lead to the highest values (80-90%) of test-retest reliability in the spatial activation map yet reported in imaging higher level visual functions. FPS-fMRI opens a new avenue for understanding brain function with low-temporal resolution methods.

Middle Helladic Period

DEFF Research Database (Denmark)

Sarri, Kalliopi

1999-01-01

and their quality was improved considerably toward the end of this period. The profound cultural innovations of the Middle Helladic period were initially interpreted as a result of violent population movement and troubles provoked by the coming of the first Indo-European races. However, this matter does no more...... Helladic period is considered as a period of economic and social decline it was the time during which the mainland features merged with the insular influence, that is all the Aegean elements which led to the creation of the Mycenaean civilization were mixed in a creative way....

Mammalian cycles: internally defined periods and interaction-driven amplitudes

Directory of Open Access Journals (Sweden)

LR Ginzburg

2015-08-01

Full Text Available The cause of mammalian cycles—the rise and fall of populations over a predictable period of time—has remained controversial since these patterns were first observed over a century ago. In spite of extensive work on observable mammalian cycles, the field has remained divided upon what the true cause is, with a majority of opinions attributing it to either predation or to intra-species mechanisms. Here we unite the eigenperiod hypothesis, which describes an internal, maternal effect-based mechanism to explain the cycles’ periods with a recent generalization explaining the amplitude of snowshoe hare cycles in northwestern North America based on initial predator abundance. By explaining the period and the amplitude of the cycle with separate mechanisms, a unified and consistent view of the causation of cycles is reached. Based on our suggested theory, we forecast the next snowshoe hare cycle (predicted peak in 2016 to be of extraordinarily low amplitude.

Oxytocin impedes the effect of the word blindness post-hypnotic suggestion on Stroop task performance.

Science.gov (United States)

Parris, Benjamin A; Dienes, Zoltan; Bate, Sarah; Gothard, Stace

2014-07-01

The ability to enhance sensitivity to relevant (post)hypnotic suggestions has implications for creating clinically informed analogues of psychological and neuropsychological conditions and for the use of hypnotic interventions in psychological and medical conditions. The aim of this study was to test the effect of oxytocin inhalation on a post-hypnotic suggestion that previously has been shown to improve the selectivity of attention in the Stroop task. In a double-blind placebo-controlled between-subjects study, medium hypnotizable individuals performed the Stroop task under normal conditions and when they had been given a post-hypnotic suggestion that they would perceive words as meaningless symbols. In line with previous research, Stroop interference was substantially reduced by the suggestion in the placebo condition. However, contrary to expectations, oxytocin impeded the effect of the word blindness suggestion on performance. The results are explained in terms of the requirement for the re-implementation of the word blindness suggestion on a trial-by-trial basis and the need to sustain activation of the suggestion between trials. The findings contrast with a recent study showing a beneficial effect of oxytocin on sensitivity to (post)hypnotic suggestions but are consistent with findings showing a detrimental effect of oxytocin on memory processes. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Multimarker analysis suggests the involvement of BDNF signaling and microRNA biosynthesis in suicidal behavior.

Science.gov (United States)

Pulay, Attila J; Réthelyi, János M

2016-09-01

Despite moderate heritability estimates the genetics of suicidal behavior remains unclear, genome-wide association and candidate gene studies focusing on single nucleotide associations reported inconsistent findings. Our study explored biologically informed, multimarker candidate gene associations with suicidal behavior in mood disorders. We analyzed the GAIN Whole Genome Association Study of Bipolar Disorder version 3 (n = 999, suicidal n = 358) and the GAIN Major Depression: Stage 1 Genomewide Association in Population-Based Samples (n = 1,753, suicidal n = 245) datasets. Suicidal behavior was defined as severe suicidal ideation or attempt. Candidate genes were selected based on literature search (Geneset1, n = 35), gene expression data of microRNA genes, (Geneset2, n = 68) and their target genes (Geneset3, n = 11,259). Quality control, dosage analyses were carried out with PLINK. Gene-based associations of Geneset1 were analyzed with KGG. Polygenic profile scores of suicidal behavior were computed in the major depression dataset both with PRSice and LDpred and validated in the bipolar disorder data. Several nominally significant gene-based associations were detected, but only DICER1 associated with suicidal behavior in both samples, while only the associations of NTRK2 in the depression sample reached family wise and experiment wise significance. Polygenic profile scores negatively predicted suicidal behavior in the bipolar sample for only Geneset2, with the strongest prediction by PRSice at Pt  suicide and the cross-disorder association of DICER1. Polygenic risk prediction of the selected miRNA genes indicates that the miRNA system may play a mediating role, but with considerable pleiotropy. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere.

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Yoncheva, Yuliya; Maurer, Urs; Zevin, Jason D; McCandliss, Bruce D

2014-08-15

Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective attention to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by manipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data-driven source localization analyses revealed that selective attention to phonology led to significantly greater recruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings suggest a key role for selective attention in on-line phonological computations. Furthermore, these findings motivate future research on the role that neural mechanisms of attention may

Periodicity and quasi-periodicity for super-integrable hamiltonian systems

International Nuclear Information System (INIS)

Kibler, M.; Winternitz, P.

1990-01-01

Classical trajectories are calculated for two Hamiltonian systems with ring shaped potentials. Both systems are super-integrable, but not maximally super-integrable, having four globally defined single-valued integrals of motion each. All finite trajectories are quasi-periodical; they become truly periodical if a commensurability condition is imposed on an angular momentum component

Disability in Mexico: a comparative analysis between descriptive models and historical periods using a timeline

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Hugo Sandoval

2017-07-01

Full Text Available Some interpretations frequently argue that three Disability Models (DM (Charity, Medical/Rehabilitation, and Social correspond to historical periods in terms of chronological succession. These views permeate a priori within major official documents on the subject in Mexico. This paper intends to test whether this association is plausible by applying a timeline method. A document search was made with inclusion and exclusion criteria in databases to select representative studies with which to depict milestones in the timelines for each period. The following is demonstrated: 1 models should be considered as categories of analysis and not as historical periods, in that the prevalence of elements of the three models is present to date, and 2 the association between disability models and historical periods results in teleological interpretations of the history of disability in Mexico.

A two-step patterning process increases the robustness of periodic patterning in the fly eye.

Science.gov (United States)

Gavish, Avishai; Barkai, Naama

2016-06-01

Complex periodic patterns can self-organize through dynamic interactions between diffusible activators and inhibitors. In the biological context, self-organized patterning is challenged by spatial heterogeneities ('noise') inherent to biological systems. How spatial variability impacts the periodic patterning mechanism and how it can be buffered to ensure precise patterning is not well understood. We examine the effect of spatial heterogeneity on the periodic patterning of the fruit fly eye, an organ composed of ∼800 miniature eye units (ommatidia) whose periodic arrangement along a hexagonal lattice self-organizes during early stages of fly development. The patterning follows a two-step process, with an initial formation of evenly spaced clusters of ∼10 cells followed by a subsequent refinement of each cluster into a single selected cell. Using a probabilistic approach, we calculate the rate of patterning errors resulting from spatial heterogeneities in cell size, position and biosynthetic capacity. Notably, error rates were largely independent of the desired cluster size but followed the distributions of signaling speeds. Pre-formation of large clusters therefore greatly increases the reproducibility of the overall periodic arrangement, suggesting that the two-stage patterning process functions to guard the pattern against errors caused by spatial heterogeneities. Our results emphasize the constraints imposed on self-organized patterning mechanisms by the need to buffer stochastic effects. Author summary Complex periodic patterns are common in nature and are observed in physical, chemical and biological systems. Understanding how these patterns are generated in a precise manner is a key challenge. Biological patterns are especially intriguing, as they are generated in a noisy environment; cell position and cell size, for example, are subject to stochastic variations, as are the strengths of the chemical signals mediating cell-to-cell communication. The need

Kerathocyst odontogenic tumor: Importance of selection the best treatment modality and a periodical follow-up to prevent from recurrence: A case report and literature review

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Nasim Jafaripozve

2013-01-01

Full Text Available The keratocystic odontogenic tumor (KCOT is a relatively common oral and maxillofacial lesion with specific characteristics such us rapid growth, extension into the surrounding tissues and high rates of recurrence. Various treatment modalities have been reported. Due to the very thin and friable lining characteristic of the tumor, enucleation can be difficult undertaken and for this reason it is associated with the highest recurrence rates. A 22-year-old male referred to our clinic due to a slight expansion in the right mandible from 2 years ago. He has a history of occurrence of KCOT in this region that was treated surgically by enucleation and curettage 5 years ago. Cone beam computed tomography showed a multilocular radiolucent lesion that extended from the angle of the mandible to the symphysis. Incisional biopsy showed a KCOT recurrence that surgically treated with resection of the right mandible by continuity preservation. Selection of the best treatment modality and also a periodical lifelong follow-up is very important to reduce the rate of recurrence and morbidity of the patient.

The influence of suggestibility on memory.

Science.gov (United States)

Nicolas, Serge; Collins, Thérèse; Gounden, Yannick; Roediger, Henry L

2011-06-01

We provide a translation of Binet and Henri's pioneering 1894 paper on the influence of suggestibility on memory. Alfred Binet (1857-1911) is famous as the author who created the IQ test that bears his name, but he is almost unknown as the psychological investigator who generated numerous original experiments and fascinating results in the study of memory. His experiments published in 1894 manipulated suggestibility in several ways to determine effects on remembering. Three particular modes of suggestion were employed to induce false recognitions: (1) indirect suggestion by a preconceived idea; (2) direct suggestion; and (3) collective suggestion. In the commentary we suggest that Binet and Henri's (1894) paper written over 115 years ago is still highly relevant even today. In particular, Binet's legacy lives on in modern research on misinformation effects in memory, in studies of conformity, and in experiments on the social contagion of memory. Copyright © 2010 Elsevier Inc. All rights reserved.

Representational constraints on children's suggestibility.

Science.gov (United States)

Ceci, Stephen J; Papierno, Paul B; Kulkofsky, Sarah

2007-06-01

In a multistage experiment, twelve 4- and 9-year-old children participated in a triad rating task. Their ratings were mapped with multidimensional scaling, from which euclidean distances were computed to operationalize semantic distance between items in target pairs. These children and age-mates then participated in an experiment that employed these target pairs in a story, which was followed by a misinformation manipulation. Analyses linked individual and developmental differences in suggestibility to children's representations of the target items. Semantic proximity was a strong predictor of differences in suggestibility: The closer a suggested distractor was to the original item's representation, the greater was the distractor's suggestive influence. The triad participants' semantic proximity subsequently served as the basis for correctly predicting memory performance in the larger group. Semantic proximity enabled a priori counterintuitive predictions of reverse age-related trends to be confirmed whenever the distance between representations of items in a target pair was greater for younger than for older children.

Frequency selective surfaces integrated with phased array antennas

NARCIS (Netherlands)

Monni, S.

2005-01-01

Frequency Selective Surfaces (FSS's) are periodic arrays of patches and/or slots etched on a metal plate, having frequency and angular ??ltering properties. The FSS response to an excitation (for example a plane wave) is characterized in terms of its re ection and transmission coe??cient, and

Individual Alpha Peak Frequency Predicts 10 Hz Flicker Effects on Selective Attention.

Science.gov (United States)

Gulbinaite, Rasa; van Viegen, Tara; Wieling, Martijn; Cohen, Michael X; VanRullen, Rufin

2017-10-18

Rhythmic visual stimulation ("flicker") is primarily used to "tag" processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (∼10 Hz) oscillations during a selective visuospatial attention task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen flanker task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed-effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs low selective attention demands). Crucially, the effect of 10 Hz flicker on task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the task). Finally, the flicker effect on task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms. SIGNIFICANCE STATEMENT Here we provide novel evidence that the interaction between exogenous rhythmic visual stimulation and endogenous brain rhythms can have frequency-specific behavioral effects. We show that alpha-band (10 Hz) flicker impairs stimulus

PLANET HUNTERS: ASSESSING THE KEPLER INVENTORY OF SHORT-PERIOD PLANETS

International Nuclear Information System (INIS)

Schwamb, Megan E.; Lintott, Chris J.; Lynn, Stuart; Smith, Arfon M.; Simpson, Robert J.; Fischer, Debra A.; Giguere, Matthew J.; Brewer, John M.; Parrish, Michael; Schawinski, Kevin

2012-01-01

We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of ≥2 R ⊕ planets on short-period ( ⊕ Planet Hunters ≥85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler ≥4 R ⊕ planets suggests that the Kepler inventory of ≥4 R ⊕ short-period planets is nearly complete.

Pertussis may be the cause of prolonged cough in adolescents and adults in the interepidemic period.

Science.gov (United States)

Pimentel, Analíria Moraes; Baptista, Paulo Neves; Ximenes, Ricardo Arraes de Alencar; Rodrigues, Laura Cunha; Magalhães, Vera; Silva, Andrea Rosane Sousa; Souza, Nadjla Ferreira; Matos, Deize Gomes Cavalcanti de; Pessoa, Ana Kelly Lins

2015-01-01

This study was aimed to evaluate the prevalence of pertussis in adolescents and adults with cough lasting more than 14 days and less than 30 days. This is a prospective observational study in interepidemic period of pertusis. Ten public health outpatient clinics in the city of Recife, Brazil, were randomly selected for the study. The study population consisted of individuals aged 10 years and over with cough that had lasted between 14 and 30 days. Nasopharyngeal swabs were collected for culture and PCR in order to identify Bordetella pertussis. We adopted the Centers for Disease Control and Prevention in the US (CDC) definition of cases of pertussis. A total of 192 individuals were identified as suspected cases. Their mean age was 40.7 years. Pertussis was confirmed in 10 of the 192 suspected cases, with an estimated prevalence of 5.21% (95% confidence interval 2.03-8.38). All cases met the clinical case definition for pertussis; one suspect had both culture and PCR positive. PCR confirmed 100% of the cases, 7/10 by PCR and 3/10 by epidemiological linkage with a case confirmed by PCR. During an interepidemic period, 1 in 20 cases of prolonged cough had pertussis, suggesting this is an important cause of prolonged cough in adolescents and adults. Copyright © 2014. Published by Elsevier Editora Ltda.

The role of suggestibility in determinations of Miranda abilities: a study of the Gudjonsson Suggestibility Scales.

Science.gov (United States)

Rogers, Richard; Harrison, Kimberly S; Rogstad, Jill E; LaFortune, Kathryn A; Hazelwood, Lisa L

2010-02-01

Traditionally, high levels of suggestibility have been widely assumed to be linked with diminished Miranda abilities, especially in relationship to the voluntariness of waivers. The current investigation examined suggestibility on the Gudjonsson Suggestibility Scales in a multisite study of pretrial defendants. One important finding was the inapplicability of British norms to American jurisdictions. Moreover, suggestibility appeared unrelated to Miranda comprehension, reasoning, and detainees' perceptions of police coercion. In testing rival hypotheses, defendants with high compliance had significantly lower Miranda comprehension and ability to reason about exercising Miranda rights than their counterparts with low compliance. Implications of these findings to forensic practice are examined.

α1-Blockers in Men with Lower Urinary Tract Symptoms Suggestive of Benign Prostatic Obstruction: Is Silodosin Different?

Science.gov (United States)

Roehrborn, Claus G; Cruz, Francisco; Fusco, Ferdinando

2017-01-01

Available α1-blockers (ABs) have different profiles of receptor selectivity. Silodosin exhibits the highest selectivity for the α 1A adrenergic receptor. This pharmacological feature couples with a singular urodynamic and clinical profile. The magnitude of bladder outlet obstruction improvement in patients receiving silodosin is higher if compared to other ABs. From a clinical point of view, current evidence suggests an advantage in favor of silodosin in terms of nocturia improvement and cardiovascular safety. The incidence of ejaculatory dysfunction with silodosin is higher compared to other Abs.

Public digital bookkeeping system: a bibliometric survey in the period 2007 to 2016

Directory of Open Access Journals (Sweden)

Gilberto Magalhães da Silva Filho

2017-12-01

Full Text Available The Public Digital Bookkeeping System represents a large database that gathers accounting, tax and payroll information, administered by federal revenue, the creation and implementation of SPED represented a major change in the accounting area and that has reflected in the after 10 years of its implementation, and after the importance of the theme, the objective of the research was to carry out a bibliometric survey of the articles published in the period 2007 to 2016, in the periodicals with Qualis/Capes A2 – B5, which dealt with the Public Information System Digital Bookkeeping – SPED. For the mapping of the research and definition of the sample, a search for key words and analysis of the abstracts in sequence was carried out in the periodicals listed on the website of the National Association of Postgraduate Programs in Accounting Sciences – ANPCONT. After the selection, the bibliometric analysis was based on identifying the authors’ particularities, which were the topics addressed, and identifying the methodologies and theories used. Of the 28 journals analyzed, 14 (50% did not present publications related to the theme in the period. Eighteen researches were selected by alignment with the topic addressed. The findings of the research showed that there was a shortage of articles that dealt with the researched subject of SPED, most of the articles were limited to a descriptive analysis of the data and little inference was made by the authors, in addition the articles that dealt with the SPED were basically limited to Dealing with the advantages and disadvantages provided by SPED, the benefits and difficulties resulting from the SPED, leaving a gap for future research.

A Study of Stochastic Resonance in the Periodically Forced Rikitake Dynamo

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Chien-Chih Chen Chih-Yuan Tseng

2007-01-01

Full Text Available The geodynamo has widely been thought to be an intuitive and selfsustained model of the Earth¡¦s magnetic field. In this paper, we elucidate how a periodic signal could be embedded in the geomagnetic filed via the mechanism of stochastic resonance in a forced Rikitake dynamo. Based on the stochastic resonance observed in the periodically forced Rikitake dynamo, we thus suggest a common triggering for geomagnetic reversal and glacial events. Both kinds of catastrophes may result from the cyclic variation of the Earth¡¦s orbital eccentricity.

Selection of target mutation in rat gastrointestinal tract E. coli by minute dosage of enrofloxacin.

Science.gov (United States)

Lin, Dachuan; Chen, Kaichao; Li, Ruichao; Liu, Lizhang; Guo, Jiubiao; Yao, Wen; Chen, Sheng

2014-01-01

It has been suggested that bacterial resistance is selected within a mutation selection window of antibiotics. More recent studies showed that even extremely low concentration of antibiotic could select resistant bacteria in vitro. Yet little is known about the exact antibiotic concentration range that can effectively select for resistant organisms in animal gastrointestinal (GI) tract. In this study, the effect of different dosages of enrofloxacin on resistance and mutation development in rat GI tract E. coli was investigated by determining the number of resistant E. coli recoverable from rat fecal samples. Our data showed that high dose antibiotic treatment could effectively eliminate E. coli with single gyrA mutation in the early course of treatment, yet the eradication effects diminished upon prolonged treatment. Therapeutic and sub-therapeutic dose (1/10 and 1/100 of therapeutic doses) of enrofloxacin could effectively select for mutation in GI tract E. coli at the later course of enrofloxacin treatment and during the cessation periods. Surprisingly, very low dose of enrofloxacin (1/1000 therapeutic dose) could also select for mutation in GI tract E. coli at the later course of enrofloxacin treatment, only with slightly lower efficiency. No enrofloxacin-resistant E. coli could be selected at all test levels of enrofloxacin during long term treatment and the strength of antibiotic treatment does not alter the overall level of E. coli in rat GI tract. This study demonstrated that long term antibiotic treatment seems to be the major trigger for the development of target mutations in GI tract E. coli, which provided insight into the rational use of antibiotics in animal husbandry.

The Effectiveness of Life Skills Training on Enhancement of Self-Esteem and Marital Satisfaction among Addicts in Treatment Period

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R Nooripour

2014-11-01

Full Text Available Objective: This study has been done to determine the impact of life skills training on enhancement of self-esteem and marital satisfaction among addicts in treatment period. Method: The research design was semi experimental pretest-posttest with witness group. For each group 12men addicts in treatment period in Qazvin city were selected by available sampling. Rosenberg self-esteem and Enrich marital satisfaction questionnaires were administered among selected samples. Training workshop was conducted on role playing, questioning and answering which was taught by psychology professors in experimental group. Results: Results showed life skills training improved self-esteem and marital satisfaction of addicts in treatment period. Conclusion: Life skills training have a positive impact on self-esteem and marital satisfaction of individuals especially on addicts in treatment period, also life skills training in the field of smoking prevention enhances individuals’ skills (such as self-esteem, marital satisfaction, etc…. Life skills training empower person to actualize his knowledge, attitudes and values, and enable him to have motivation for healthy behavior which this will have significant impact on his relationship with his wife.

Sexual selection predicts advancement of avian spring migration in response to climate change

DEFF Research Database (Denmark)

Spottiswoode, Claire N; Tøttrup, Anders P; Coppack, Timothy

2006-01-01

Global warming has led to earlier spring arrival of migratory birds, but the extent of this advancement varies greatly among species, and it remains uncertain to what degree these changes are phenotypically plastic responses or microevolutionary adaptations to changing environmental conditions. We...... suggest that sexual selection could help to understand this variation, since early spring arrival of males is favoured by female choice. Climate change could weaken the strength of natural selection opposing sexual selection for early migration, which would predict greatest advancement in species...... in the timing of first-arriving individuals, suggesting that selection has not only acted on protandrous males. These results suggest that sexual selection may have an impact on the responses of organisms to climate change, and knowledge of a species' mating system might help to inform attempts at predicting...

Groundwater-quality data in 12 GAMA study units: Results from the 2006–10 initial sampling period and the 2008–13 trend sampling period, California GAMA Priority Basin Project

Science.gov (United States)

Mathany, Timothy M.

2017-03-09

The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey in cooperation with the California State Water Resources Control Board. From 2004 through 2012, the GAMA-PBP collected samples and assessed the quality of groundwater resources that supply public drinking water in 35 study units across the State. Selected sites in each study unit were sampled again approximately 3 years after initial sampling as part of an assessment of temporal trends in water quality by the GAMA-PBP. Twelve of the study units, initially sampled during 2006–11 (initial sampling period) and sampled a second time during 2008–13 (trend sampling period) to assess temporal trends, are the subject of this report.The initial sampling was designed to provide a spatially unbiased assessment of the quality of untreated groundwater used for public water supplies in the 12 study units. In these study units, 550 sampling sites were selected by using a spatially distributed, randomized, grid-based method to provide spatially unbiased representation of the areas assessed (grid sites, also called “status sites”). After the initial sampling period, 76 of the previously sampled status sites (approximately 10 percent in each study unit) were randomly selected for trend sampling (“trend sites”). The 12 study units sampled both during the initial sampling and during the trend sampling period were distributed among 6 hydrogeologic provinces: Coastal (Northern and Southern), Transverse Ranges and Selected Peninsular Ranges, Klamath, Modoc Plateau and Cascades, and Sierra Nevada Hydrogeologic Provinces. For the purposes of this trend report, the six hydrogeologic provinces were grouped into two hydrogeologic regions based on location: Coastal and Mountain.The groundwater samples were analyzed for a number of synthetic organic

Directional and balancing selection in human beta-defensins

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Armour John AL

2008-04-01

Full Text Available Abstract Background In primates, infection is an important force driving gene evolution, and this is reflected in the importance of infectious disease in human morbidity today. The beta-defensins are key components of the innate immune system, with antimicrobial and cell signalling roles, but also reproductive functions. Here we examine evolution of beta-defensins in catarrhine primates and variation within different human populations. Results We show that five beta-defensin genes that do not show copy number variation in humans show evidence of positive selection in catarrhine primates, and identify specific codons that have been under selective pressure. Direct haplotyping of DEFB127 in humans suggests long-term balancing selection: there are two highly diverged haplotype clades carrying different variants of a codon that, in primates, is positively selected. For DEFB132, we show that extensive diversity, including a four-state amino acid polymorphism (valine, isoleucine, alanine and threonine at position 93, is present in hunter-gatherer populations, both African and non-African, but not found in samples from agricultural populations. Conclusion Some, but not all, beta-defensin genes show positive selection in catarrhine primates. There is suggestive evidence of different selective pressures on these genes in humans, but the nature of the selective pressure remains unclear and is likely to differ between populations.

Genetic variation and selection of MHC class I loci differ in two congeneric frogs.

Science.gov (United States)

Kiemnec-Tyburczy, Karen M; Tracy, Karen E; Lips, Karen R; Zamudio, Kelly R

2018-04-01

Major histocompatibility complex (MHC) genes encode proteins in the acquired immune response pathway that often show distinctive selection-driven patterns in wild vertebrate populations. We examined genetic variation and signatures of selection in the MHC class I alpha 1 (A1)- and alpha 2 (A2)-domain encoding exons of two frog congeners [Agalychnis callidryas (n = 20) and A. lemur (n = 20)] from a single locality in Panama. We also investigated how historical demographic processes may have impacted MHC genetic diversity by analyzing a neutral mitochondrial marker. We found that both MHC domains were highly variable in both species, with both species likely expressing three loci. Our analyses revealed different signatures of selection between the two species, most notably that the A. callidryas A2 domain had experienced positive selection while the A2 domain of A. lemur had not. Diversifying selection acted on the same number of A1 and A2 allelic lineages, but on a higher percentage of A1 sites compared to A2 sites. Neutrality tests of mitochondrial haplotypes predominately indicated that the two species were at genetic equilibrium when the samples were collected. In addition, two historical tests of demography indicated both species have had relatively stable population sizes over the past 100,000 years; thus large population size changes are unlikely to have greatly influenced MHC diversity in either species during this time period. In conclusion, our results suggest that the impact of selection on MHC diversity varied between these two closely related species, likely due to a combination of distinct ecological conditions and past pathogenic pressures.

Genetic search feature selection for affective modeling

DEFF Research Database (Denmark)

Martínez, Héctor P.; Yannakakis, Georgios N.

2010-01-01

Automatic feature selection is a critical step towards the generation of successful computational models of affect. This paper presents a genetic search-based feature selection method which is developed as a global-search algorithm for improving the accuracy of the affective models built....... The method is tested and compared against sequential forward feature selection and random search in a dataset derived from a game survey experiment which contains bimodal input features (physiological and gameplay) and expressed pairwise preferences of affect. Results suggest that the proposed method...

Reinventing suggestion systems for continuous improvement

NARCIS (Netherlands)

Schuring, R.W.; Luijten, Harald

2001-01-01

This article reports an experiment to increase the effectiveness of a suggestion system by deliberately applying principles of the kaizen and performance management. Design rules for suggestion systems are derived from these theories. The suggestion system that resulted differs from traditional

Suggestive Objects at Work

DEFF Research Database (Denmark)

Ratner, Helene Gad

2009-01-01

In Western secular societies, spiritual life is no longer limited to classical religious institutions but can also be found at workplace organizations. While spirituality is conventionally understood as a subjective and internal process, this paper proposes the concept of ‘suggestive objects......’, constructed by combining insights from Gabriel Tarde's sociology with Bruno Latour's actor-network theory, to theorize the material dimension of organizational spirituality. The sacred in organizations arises not from the internalization of collective values but through the establishment of material...... scaffolding. This has deep implications for our understanding of the sacred, including a better appreciation of the way that suggestive objects make the sacred durable, the way they organize it....

Periodic safety re-evaluations in NPPs in EC member states, Finland and Sweden

International Nuclear Information System (INIS)

1990-01-01

The work on periodic safety re-evaluations summarized in this report was performed by a Task Force of the CEC Working Group on the Safety of Thermal Reactors. The periodic safety re-evaluations under review in this study were those that are carried out in addition to other reviews which represent the primary means of safety assurance. The periodic safety re-evaluation is broader and more comprehensive in nature. The cumulative effects of experience (national and international), advances in knowledge and analysis techniques, improvements in safety standards and operating practices, overall effects of plant ageing, and the totality of all modifications over the period in question need to be taken into account. All countries have recognized the value of such periodic reviews, and licensees, either as a regulatory requirement or as a voluntary action, are carrying them out. The scope and contents of each country's review showed many similarities of approach, any differences being explained by the age and type of reactor in operation. Many similarities emerged in the topics selected for re-evaluation and in the approach to re-evaluation itself. The overall conclusion was that while approaches may differ in some respects, for practical purposes comparable levels of safety are achieved in the periodic safety re-evaluation of nuclear power plants

A duty-period-based formulation of the airline crew scheduling problem

Energy Technology Data Exchange (ETDEWEB)

Hoffman, K.

1994-12-31

We present a new formulation of the airline crew scheduling problem that explicitly considers the duty periods. We suggest an algorithm for solving the formulation by a column generation approach with branch-and-bound. Computational results are reported for a number of test problems.

PERIOD ESTIMATION FOR SPARSELY SAMPLED QUASI-PERIODIC LIGHT CURVES APPLIED TO MIRAS

Energy Technology Data Exchange (ETDEWEB)

He, Shiyuan; Huang, Jianhua Z.; Long, James [Department of Statistics, Texas A and M University, College Station, TX (United States); Yuan, Wenlong; Macri, Lucas M., E-mail: lmacri@tamu.edu [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX (United States)

2016-12-01

We develop a nonlinear semi-parametric Gaussian process model to estimate periods of Miras with sparsely sampled light curves. The model uses a sinusoidal basis for the periodic variation and a Gaussian process for the stochastic changes. We use maximum likelihood to estimate the period and the parameters of the Gaussian process, while integrating out the effects of other nuisance parameters in the model with respect to a suitable prior distribution obtained from earlier studies. Since the likelihood is highly multimodal for period, we implement a hybrid method that applies the quasi-Newton algorithm for Gaussian process parameters and search the period/frequency parameter space over a dense grid. A large-scale, high-fidelity simulation is conducted to mimic the sampling quality of Mira light curves obtained by the M33 Synoptic Stellar Survey. The simulated data set is publicly available and can serve as a testbed for future evaluation of different period estimation methods. The semi-parametric model outperforms an existing algorithm on this simulated test data set as measured by period recovery rate and quality of the resulting period–luminosity relations.

Selective plantar fascia release for nonhealing diabetic plantar ulcerations.

Science.gov (United States)

Kim, J Young; Hwang, Seungkeun; Lee, Yoonjung

2012-07-18

Achilles tendon lengthening can decrease plantar pressures, leading to resolution of forefoot ulceration in patients with diabetes mellitus. However, this procedure has been reported to have a complication rate of 10% to 30% and can require a long period of postoperative immobilization. We have developed a new technique, selective plantar fascia release, as an alternative to Achilles tendon lengthening for managing these forefoot ulcers. We evaluated sixty patients with diabetes for a mean of 23.5 months after selective plantar fascia release for the treatment of nonhealing diabetic neuropathic ulcers in the forefoot. Preoperative and postoperative dorsiflexion range of motion of the affected metatarsophalangeal joint and wound-healing data were used to evaluate the effectiveness of the procedure and to determine the relationship between plantar fascia release and ulcer healing. Complications were recorded. Thirty-six (56%) of the ulcers healed within six weeks, including twenty-nine (60%) of the plantar toe ulcers and seven (44%) of the metatarsophalangeal joint ulcers. The mean range of motion of the affected metatarsophalangeal joint increased from 15.3° ± 7.8° to 30.6° ± 14.1° postoperatively (p plantar fascia release. Our results suggest that selective plantar fascia release can lead to healing of neuropathic plantar forefoot ulcers in diabetic patients. Ulcers in patients in whom the preoperative dorsiflexion angle of the affected metatarsophalangeal joint is between 5° and 30° and in whom the increase in range of motion is ≥13° postoperatively have the greatest chance of being cured. Therapeutic level IV. See Instructions for Authors for a complete description of the levels of evidence.

PEMBENTUKAN PORTOFOLIO OPTIMAL SAHAM-SAHAM PADA PERIODE BULLISH DI BURSA EFEK INDONESIA

Directory of Open Access Journals (Sweden)

Suramaya Suci Kewal

2013-04-01

Full Text Available Abstrak: Pembentukan Portofolio Optimal Saham-Saham Pada Periode Bullish Di Bursa Efek Indonesia. Penelitian ini dilakukan dengan tujuan untuk menyusun portofolio optimal saham yang tercatat di Bursa Efek Indonesia dengan menggunakan model indeks tunggal pada periode Bullish. Periode penelitian yang digunakan dalam penelitian ini adalah 2009-2011. Hasilnya adalah tersusunnya sebuah portofolio saham yang terdiri dari empat saham, yaitu ASRI (48,72%, INDF (28,24%, BBNI (16,32%, dan BKSL (6.71%. Hasil pengujian hipotesis pertama menunjukkan bahwa ada perbedaan dalam return saham dari portofolio candidate dibandingkan dengan portofolio noncandidate. Hasil pengujian hipotesis kedua menunjukkan bahwa tidak ada perbedaan dalam risiko saham yang termasuk dalam portofolio candidate dibandingkan dengan portofolio noncandidate. Kata kunci: portofolio optimal, model single-index   Abstract: Establishment of Optimal Portfolio Shares On Bullish Period In Indonesia Stock Exchange. This study was conducted in order to establish an optimal portfolio of stocks listed on the Indonesia Stock Exchange using a single index model on Bullish conditions. Period of research used in this study is 2009-2011. The result is the formation of a stock portfolio consisting of four stocks, namely ASRI (48.72%, INDF (28.24%, BBNI (16.32%, and BKSL (6.71%. The test results of the first hypothesis suggests that there are differences in stock returns a stock portfolio of candidates as compared to the noncandidate portfolio. The results of testing the second hypothesis suggests that there is no difference in the risk of stocks included in candidate portfolios as compared to the noncandidate portfolio. Keywords: optimal portfolios, single-index models

Not looking yourself: The cost of self-selecting photographs for identity verification.

Science.gov (United States)

White, David; Burton, Amy L; Kemp, Richard I

2016-05-01

Photo-identification is based on the premise that photographs are representative of facial appearance. However, previous studies show that ratings of likeness vary across different photographs of the same face, suggesting that some images capture identity better than others. Two experiments were designed to examine the relationship between likeness judgments and face matching accuracy. In Experiment 1, we compared unfamiliar face matching accuracy for self-selected and other-selected high-likeness images. Surprisingly, images selected by previously unfamiliar viewers - after very limited exposure to a target face - were more accurately matched than self-selected images chosen by the target identity themselves. Results also revealed extremely low inter-rater agreement in ratings of likeness across participants, suggesting that perceptions of image resemblance are inherently unstable. In Experiment 2, we test whether the cost of self-selection can be explained by this general disagreement in likeness judgments between individual raters. We find that averaging across rankings by multiple raters produces image selections that provide superior identification accuracy. However, benefit of other-selection persisted for single raters, suggesting that inaccurate representations of self interfere with our ability to judge which images faithfully represent our current appearance. © 2015 The British Psychological Society.