bluuebunny/crossref_metadata_2025_split huggingface dataset:
Indirect force control development procedure
Authors: Winiarski Tomasz , Woźniak Adam 
Published: August 2012

SUMMARYAddition of extra sensors, especially video cameras and force sensors, under control of appropriate software makes robotic manipulators working in factories suitable for a range of new applications. This paper presents a method of manipulator indirect force control development, in which the force set values are specified in the operational space and the manipulator is equipped with a force sensor in its wrist. Standard control development methods need the estimation of parameters of the detailed model of a manipulator and position servos, which is a complicated and time-consuming task. Hence, in this work a time-efficient hybrid procedure of controller development is proposed consisting of both analytical and experimental stages: proposal of an approximate continuous model of a manipulator, experimental determination and verification of its parameter values using the resonance phenomenon, continuous regulator development, and digitization of the regulator.
Generalized maximum principles and the rigidity of complete spacelike hypersurfaces
Authors: CAMARGO FERNANDA , CAMINHA ANTONIO , DE LIMA HENRIQUE , PARENTE ULISSES 
Published: August 2012

AbstractIn this paper, we apply several forms of generalized maximum principles to the study of the uniqueness of complete, non-compact spacelike hypersurfaces immersed in a class of Lorentzian warped products obeying a suitable convergence condition.
Comparative assessment of different methods for using land-cover variables for distribution modelling ofSalamandra salamandra longirotris
Authors: ROMERO DAVID , OLIVERO JESÚS , REAL RAIMUNDO 
Published: August 2012

SUMMARYPredictive models are frequently used to define the most suitable areas for species protection or reintroduction. Land-cover variables can be used in different ways for distribution modelling. The surface area of a set of land-cover classes is often used, each land-cover presence/absence or the distance to them from any point of the study area can be preferred; multiple types of land-cover variables may be combined to produce a single model. This paper assesses whether different approaches to using land-cover variables may lead to different ecological conclusions when interpreted for conservation by focusing on the distribution of the salamaderSalamandra salamandra longirostris, an endangered amphibian subspecies in the south of the Iberian Peninsula. Twenty-eight land-cover classes and another 42 environmental variables were used to construct four different models. Three models used a unique type of land-cover variable: either the presence of each class, the surface area of each class or the distance to each class, with all three variable types jointly entered in a fourth model. All models attained acceptable scores according to some criteria (discrimination, descriptive and predictive capacities, classification accuracy and parsimony); however most of the assessment parameters computed indicated a better performance of the models using either the surface area of land classes or the distance to them from every sampled square, compared to the model using class presences. The best scores were obtained with the fourth model, which combined different types of land-cover variables. This model suggested that oak forest fragmentation in favour of herbaceous crops and pastures may have negative effects on the distribution ofS. s. longirostris. This was only partially suggested by the first three models, which considered a single type of land-cover variable, demonstrating the importance of considering a multi-variable analysis for conservation planning.
Lifestyle values, resilience, and nature-based tourism's contribution to conservation on Australia's Great Barrier Reef
Authors: BIGGS D. , BAN N. C. , HALL C. M. 
Published: August 2012

SUMMARYInnovative partnerships for conservation are required to stem the tide of continued ecosystem degradation. Nature-based tourism is one such partnership. Yet the natural attractions that nature-based tourism depends on are under increasing anthropogenic threat. Because of their dependence on international visitors, nature-based tourism enterprises are under additional pressure from socioeconomic and political crises in a globalized world. Recent research shows that lifestyle values, the motives that entice owners and staff of tourism enterprises to live and work in a chosen natural attraction, strengthen the resilience of enterprises to crises. This paper empirically explores the relationship between the lifestyle values of nature-based tourism enterprises, their resilience, and their support of and contribution to conservation of Australia's Great Barrier Reef. Semi-structured interviews with the owners and senior managers of 48 reef tourism enterprises showed that those that reported high lifestyle values had higher levels of conservation ethic and participated more extensively in conservation actions. The relationship between resilience and conservation ethic was not statistically significant. Bureaucratic, regulatory and cost constraints, and a lack of knowledge, limit enterprise participation in conservation. Conservation agencies can work to reduce some of these constraints to ensure that conservation benefits from nature-based tourism enterprises are maximized.
Cops and Robbers on Geometric Graphs
Authors: BEVERIDGE ANDREW , DUDEK ANDRZEJ , FRIEZE ALAN , MÜLLER TOBIAS 
Published: August 2012

Cops and robbers is a turn-based pursuit game played on a graph G. One robber is pursued by a set of cops. In each round, these agents move between vertices along the edges of the graph. The cop number c(G) denotes the minimum number of cops required to catch the robber in finite time. We study the cop number of geometric graphs. For points x1, . . ., xn ∈ ℝ2, and r ∈ ℝ+, the vertex set of the geometric graph G(x1, . . ., xn; r) is the graph on these n points, with xi, xj adjacent when ∥xi − xj∥ ≤ r. We prove that c(G) ≤ 9 for any connected geometric graph G in ℝ2 and we give an example of a connected geometric graph with c(G) = 3. We improve on our upper bound for random geometric graphs that are sufficiently dense. Let (n,r) denote the probability space of geometric graphs with n vertices chosen uniformly and independently from [0,1]2. For G ∈ (n,r), we show that with high probability (w.h.p.), if r ≥ K1 (log n/n)1/4 then c(G) ≤ 2, and if r ≥ K2(log n/n)1/5 then c(G) = 1, where K1, K2 > 0 are absolute constants. Finally, we provide a lower bound near the connectivity regime of (n,r): if r ≤ K3 log n/ then c(G) > 1 w.h.p., where K3 > 0 is an absolute constant.
Whole grain consumption is inversely associated with BMI Z-score in rural school-aged children
Authors: Choumenkovitch Silvina F , McKeown Nicola M , Tovar Alison , Hyatt Raymond R , Kraak Vivica I , Hastings Alia V , Herzog Julia Bloom , Economos Christina D 
Published: August 2012

AbstractObjectiveTo examine the relationship between intake of whole grains and BMI Z-score in rural children.DesignGeneral linear models and logistic regression were used to examine the cross-sectional associations between whole grain intake and BMI Z-score, prevalence and odds ratios of overweight and obesity. Dietary intake was assessed using the Block Food Screener for ages 2–17 years. Children were classified into three categories according to servings of whole grain intake: <1·0 serving/d, 1·0–1·5 servings/d and >1·5 servings/d.SettingThe CHANGE (Creating Healthy, Active and Nurturing Growing-up Environments) study, an obesity prevention intervention in elementary schools in eight rural US communities in California, Mississippi, Kentucky and South Carolina.SubjectsSeven hundred and ninety-two children attending 3rd–6th grade.ResultsAfter adjusting for age, sex, race/ethnicity, physical activity and state of residence, whole grain intake was inversely associated with BMI Z-score (0·90 v. 0·61 in the lowest v. the highest whole grain intake category; P trend = 0·01). Children who consumed >1·5 servings of whole grains/d had a 40 % lower risk of being obese (OR = 0·60; 95 % CI 0·38, 0·95, P = 0·02) compared with children who consumed <1·0 serving/d. Further adjustment for potential dietary predictors of body weight (fruit, vegetable and dairy intakes) did not change the observed associations.ConclusionsIncreasing the intake of whole grains as part of an overall healthy lifestyle may be beneficial for children to achieve and maintain a healthy weight.
Dietary salt intake assessed by 24 h urinary sodium excretion in Australian schoolchildren aged 5–13 years
Authors: Grimes Carley A , Riddell Lynn J , Campbell Karen J , Nowson Caryl A 
Published: August 2012

AbstractObjectiveTo measure total daily salt intake using 24 h urinary Na excretion within a sample of Victorian schoolchildren aged 5–13 years and to assess discretionary salt use habits of children and parents.DesignCross-sectional study.SettingCompleted within a convenience sample of independent primary schools (n9) located in Victoria, Australia.SubjectsTwo hundred and sixty children completed a 24 h urine collection over a school (34 %) or non-school day (66 %). Samples deemed incomplete (n18), an over-collection (n1) or that were incorrectly processed at the laboratory (n3) were excluded.ResultsThe sample comprised 120 boys and 118 girls with a mean age of 9·8 (sd1·7) years. The average 24 h urinary Na excretion (n238) was 103 (sd43) mmol/24 h (salt equivalent 6·0 (sd2·5) g/d). Daily Na excretion did not differ by sex; boys 105 (sd46) mmol/24 h (salt equivalent 6·1 (sd2·7) g/d) and girls 100 (sd41) mmol/24 h (salt equivalent 5·9 (sd2·4) g/d;P= 0·38). Sixty-nine per cent of children (n164) exceeded the recommended daily Upper Limit for Na. Reported discretionary salt use was common: two-thirds of parents reported adding salt during cooking and almost half of children reported adding salt at the table.ConclusionsThe majority of children had salt intakes exceeding the recommended daily Upper Limit. Strategies to lower salt intake in children are urgently required, and should include product reformulation of lower-sodium food products combined with interventions targeting discretionary salt use within the home.
Relative validation of a quantitative FFQ for use in Brazilian pregnant women
Authors: Barbieri Patrícia , Nishimura Renata Y , Crivellenti Lívia C , Sartorelli Daniela S 
Published: August 2012

AbstractObjectiveTo evaluate the ability of an FFQ, designed for use in Brazilian pregnant women, to estimate nutrient intakes during pregnancy.DesignA prospective study was conducted among 103 pregnant women attended by the Brazilian national health-care service. Food intake during pregnancy was evaluated by three 24 h dietary recalls (24hR), one per trimester of pregnancy, and also by two FFQ. The FFQ with eighty-five food items included questions about frequency of intake and portion sizes during two periods: the first 24 weeks of pregnancy and the pregnancy period as a whole. Deattenuated Pearson's correlation coefficients and joint classification into quartiles of nutrient intake were applied.SettingRibeirão Preto, São Paulo State, Brazil.SubjectsOne hundred and three pregnant women, aged 18–35 years.ResultsAcceptable correlation coefficients (r > 0·35) were found for Ca, K, Zn, Mg, fibre, vitamin C, niacin and folic acid for intake for the first 24 weeks; and for energy, lipids, protein, carbohydrate, Fe, K, Zn, fibre, vitamin B6, riboflavin and niacin for the gestational period as a whole. A high proportion of study participants (≥70 %) were categorized into the same or adjacent quartiles for estimated energy, carbohydrate, Ca, K, fibre, Zn, cholesterol, vitamin A, riboflavin, niacin, vitamin C, vitamin E and folic acid. Gross misclassification ranged from 2·3 % (dietary fibre) to 12·5 % (vitamin A, thiamin and SFA).ConclusionsThe FFQ is a useful tool for assessing categories of nutrient intake during pregnancy, since a high proportion of women were classified into the same or adjacent quartiles.
Testing the fetal overnutrition hypothesis; the relationship of maternal and paternal adiposity to adiposity, insulin resistance and cardiovascular risk factors in Indian children
Authors: Veena Sargoor R , Krishnaveni Ghattu V , Karat Samuel C , Osmond Clive , Fall Caroline HD 
Published: August 2012

AbstractObjectiveWe aimed to test the fetal overnutrition hypothesis by comparing the associations of maternal and paternal adiposity (sum of skinfolds) with adiposity and cardiovascular risk factors in children.DesignChildren from a prospective birth cohort had anthropometry, fat percentage (bio-impedance), plasma glucose, insulin and lipid concentrations and blood pressure measured at 9·5 years of age. Detailed anthropometric measurements were recorded for mothers (at 30 ± 2 weeks’ gestation) and fathers (5 years following the index pregnancy).SettingHoldsworth Memorial Hospital, Mysore, India.SubjectsChildren (n504), born to mothers with normal glucose tolerance during pregnancy.ResultsTwenty-eight per cent of mothers and 38 % of fathers were overweight/obese (BMI ≥ 25·0 kg/m2), but only 4 % of the children were overweight/obese (WHO age- and sex-specific BMI ≥ 18·2 kg/m2). The children's adiposity (BMI, sum of skinfolds, fat percentage and waist circumference), fasting insulin concentration and insulin resistance increased with increasing maternal and paternal sum of skinfolds adjusted for the child's sex, age and socio-economic status. Maternal and paternal effects were similar. The associations with fasting insulin and insulin resistance were attenuated after adjusting for the child's current adiposity.ConclusionsIn this population, both maternal and paternal adiposity equally predict adiposity and insulin resistance in the children. This suggests that shared family environment and lifestyle, or genetic/epigenetic factors, influence child adiposity. Our findings do not support the hypothesis that there is an intra-uterine overnutrition effect of maternal adiposity in non-diabetic pregnancies, although we cannot rule out such an effect in cases of extreme maternal obesity, which is rare in our population.
Mini-Review: Probing the limits of extremophilic life in extraterrestrial environment-simulated experiments
Authors: Lage Claudia A.S. , Dalmaso Gabriel Z.L. , Teixeira Lia C.R.S. , Bendia Amanda G. , Paulino-Lima Ivan G. , Galante Douglas , Janot-Pacheco Eduardo , Abrevaya Ximena C. , Azúa-Bustos Armando , Pelizzari Vivian H. , Rosado Alexandre S. 
Published: August 2012

AbstractAstrobiology is a relatively recent scientific field that seeks to understand the origin and dynamics of life in the Universe. Several hypotheses have been proposed to explain life in the cosmic context throughout human history, but only now, technology has allowed many of them to be tested. Laboratory experiments have been able to show how chemical elements essential to life, such as carbon, nitrogen, oxygen and hydrogen combine in biologically important compounds. Interestingly, these compounds are ubiquitous. How these compounds were combined to the point of originating cells and complex organisms is still to be unveiled by science. However, our 4.5 billion years old Solar system appeared in a 10 billion years old Universe. Thus, simple cells such as micro-organisms may have had time to form in planets older than ours or in other suitable places in the Universe. One hypothesis related to the appearance of life on Earth is called panspermia, which predicts that microbial life could have been formed in the Universe billions of years ago, travelling between planets, and inseminating units of life that could have become more complex in habitable planets such as Earth. A project designed to test the viability of extremophile micro-organisms exposed to simulated extraterrestrial environments is in progress at the Carlos Chagas Filho Institute of Biophysics (UFRJ, Brazil) to test whether microbial life could withstand inhospitable environments. Radiation-resistant (known or novel ones) micro-organisms collected from extreme terrestrial environments have been exposed (at synchrotron accelerators) to intense radiation sources simulating Solar radiation, capable of emitting radiation in a few hours equivalent to many years of accumulated doses. The results obtained in these experiments reveal an interesting possibility of the existence of microbial life beyond Earth.
Does the US Media Have a Liberal Bias?
Authors: Rosenblum Nancy L. 
Published: August 2012

In Left Turn: How Liberal Bias Distorts The American Mind, Tim Groseclose argues that media effects play a crucial role in American politics. His case rests on three arguments: (1) that journalists tend overwhelmingly to be liberal rather than conservative; (2) that their innate political bias slants their views in empirically measurable ways; and (3) that this bias fundamentally shapes American politics, by bringing US citizens further to the left than they would naturally be. According to Groseclose, in a world where media bias did not exist, American citizens would on average hold views close to those of Ben Stein or Bill O'Reilly. In such a world, John McCain would have defeated Barack Obama by a popular vote margin of 56%—42% in the 2008 presidential election.In making these claims, Groseclose draws on his own research, and on recent media scholarship by both political scientists and economists, making the broader claim that peer-reviewed social science—which seeks to deal with problems such as endogeneity and selection bias—should be the starting point for public arguments about the role of the media. His book, then, is clearly an effort to bring social scientific arguments into mainstream debates. Groseclose makes no secret of his conservative political leanings—but recent books from left-leaning political scientists such as Jacob Hacker and Paul Pierson are equally unapologetic. It is at least plausible that political scientists' typical unwillingness to engage directly in political arguments has weakened the discipline's capacity for public engagement.In this symposium a diverse group of contributors have been invited to engage with Groseclose's arguments in ways that bring together specific empirical and/or theoretical points and arguments aimed at the broader “political science public sphere” that Perspectives on Politics seeks to nurture. Contributors were asked to consider these five questions: (1): How do we best measure media effects? (2): If media bias exists, what are its plausible sources? (3): Can one use work on media effects to determine what people's views would be in the absence of such bias? (4): Do you agree that American politics is insufficiently representative, and if so what do you consider the primary sources of this problem? (5): What kinds of political and/or media institutions or practices might enhance democratic discourse?—Henry Farrell, Associate Editor
Does the US Media Have a Liberal Bias?
Authors: Gross Justin H. , Shalizi Cosma Rohilla , Gelman Andrew 
Published: August 2012

InLeft Turn: How Liberal Bias Distorts The American Mind,Tim Groseclose argues that media effects play a crucial role in American politics. His case rests on three arguments: (1) that journalists tend overwhelmingly to be liberal rather than conservative; (2) that their innate political bias slants their views in empirically measurable ways; and (3) that this bias fundamentally shapes American politics, by bringing US citizens further to the left than they would naturally be. According to Groseclose, in a world where media bias did not exist, American citizens would on average hold views close to those of Ben Stein or Bill O'Reilly. In such a world, John McCain would have defeated Barack Obama by a popular vote margin of 56%—42% in the 2008 presidential election.In making these claims, Groseclose draws on his own research, and on recent media scholarship by both political scientists and economists, making the broader claim that peer-reviewed social science—which seeks to deal with problems such as endogeneity and selection bias—should be the starting point for public arguments about the role of the media. His book, then, is clearly an effort to bring social scientific arguments into mainstream debates. Groseclose makes no secret of his conservative political leanings—but recent books from left-leaning political scientists such as Jacob Hacker and Paul Pierson are equally unapologetic. It is at least plausible that political scientists' typical unwillingness to engage directly in political arguments has weakened the discipline's capacity for public engagement.In this symposium a diverse group of contributors have been invited to engage with Groseclose's arguments in ways that bring together specific empirical and/or theoretical points and arguments aimed at the broader “political science public sphere” thatPerspectives on Politicsseeks to nurture. Contributors were asked to consider these five questions: (1): How do we best measure media effects? (2): If media bias exists, what are its plausible sources? (3): Can one use work on media effects to determine what people's views would be in the absence of such bias? (4): Do you agree that American politics is insufficiently representative, and if so what do you consider the primary sources of this problem? (5): What kinds of political and/or media institutions or practices might enhance democratic discourse?—Henry Farrell, Associate Editor
Does the US Media Have a Liberal Bias?
Authors: Nyhan Brendan 
Published: August 2012

In Left Turn: How Liberal Bias Distorts The American Mind, Tim Groseclose argues that media effects play a crucial role in American politics. His case rests on three arguments: (1) that journalists tend overwhelmingly to be liberal rather than conservative; (2) that their innate political bias slants their views in empirically measurable ways; and (3) that this bias fundamentally shapes American politics, by bringing US citizens further to the left than they would naturally be. According to Groseclose, in a world where media bias did not exist, American citizens would on average hold views close to those of Ben Stein or Bill O'Reilly. In such a world, John McCain would have defeated Barack Obama by a popular vote margin of 56%—42% in the 2008 presidential election.In making these claims, Groseclose draws on his own research, and on recent media scholarship by both political scientists and economists, making the broader claim that peer-reviewed social science—which seeks to deal with problems such as endogeneity and selection bias—should be the starting point for public arguments about the role of the media. His book, then, is clearly an effort to bring social scientific arguments into mainstream debates. Groseclose makes no secret of his conservative political leanings—but recent books from left-leaning political scientists such as Jacob Hacker and Paul Pierson are equally unapologetic. It is at least plausible that political scientists' typical unwillingness to engage directly in political arguments has weakened the discipline's capacity for public engagement.In this symposium a diverse group of contributors have been invited to engage with Groseclose's arguments in ways that bring together specific empirical and/or theoretical points and arguments aimed at the broader “political science public sphere” that Perspectives on Politics seeks to nurture. Contributors were asked to consider these five questions: (1): How do we best measure media effects? (2): If media bias exists, what are its plausible sources? (3): Can one use work on media effects to determine what people's views would be in the absence of such bias? (4): Do you agree that American politics is insufficiently representative, and if so what do you consider the primary sources of this problem? (5): What kinds of political and/or media institutions or practices might enhance democratic discourse?—Henry Farrell, Associate Editor