Static modulus of elasticity of concrete as affected by density

"December 17, 1960.""Reprinted from, American Concrete Institute Journal, Title No. 57-32 ; V. 32 ; No. 6 ; December 1960 (Proceedings V. 57), P.O. Box 4754, Redford Station, Detroit 19, Michigan.""The elastic modulus of concrete is an important parameter in reinforced concrete design and analysis. With the increased use of lightweight aggregates for structural concrete a better understanding of the relationship between weight, strength, and the elastic modulus is needed. In this study the static modulus for a large variety of aggregates and concrete strengths was analyzed and an empirical formula was derived which is applicable to both lightweight and normal weight structural concretes. The formula is in excellent agreement with recognized empirical formulas for normal weight concrete."--Page 679

Controlled-deflection design method for reinforced concrete beams and slabs

"December 5, 1962.""Reprint from Journal of The American Concrete Institute Title 59-22, Proceedings: Vol. 59, No. 5, May 1962.""Describes a design method for reinforced concrete beams and slabs in which the allowable ratio of span to deflection is a criterion. The method may also be used for estimating deflections in given designs including those in which ultimate strength theory is used. Special emphasis is placed on design with lightweight aggregate concretes. The elastic theory only is used and estimation of the elastic modulus of concrete is based on previous work. A short-cut procedure is presented for the design of simply supported beams and slabs subjected to uniformly distributed loads only. Tables and design charts are furnished to aid computation. The problem of deflection caused by creep and shrinkage of the concrete is mentioned but not directly dealt with in this paper. The examples, therefore, deal with short-time deflections only."--Page 645

A Rational Design Procedure for Machine Foundations

The problem involved in the design of machine foundations are discussed, followed by a short review of the literature of the subject. The general theory of vibration for single and multiple degree of freedom systems is briefly reviewed, with special emphasis on its application to machine foundation design. A procedure for the analysis of machine foundations is then developed on the basis of a simplified equivalent system. Procedures for determining the elastic coefficients and the inertia parameters of the soil are next considered. The purpose and extent of the experimental investigations are discussed, followed by a description of the instrumentation used and the nature and accuracy of the data obtained. The data is then analyzed and checked against the theory presented. The data required for the design of machine foundations is discussed, and a procedure for design and analysis is recommended. In conclusion recommendations for further study and research are made.</p

Effect of creep and shrinkage on the behavior of reinforced concrete members

Two titles published in one volume. "Creep of concrete: influencing factors and prediction" by Adam M Neville and Bernard L. Meyers and "Effect of creep and shrinkage on the behavior of reinforced concrete members" by Adrian Pauw and Bernard L. Meyers."Reprinted from Symposium on Creep of Concrete ; Publication SP-9, The American Concrete Institute.

Global agricultural productivity is threatened by increasing pollinator dependence without a parallel increase in crop diversification

The global increase in the proportion of land cultivated with pollinator-dependent crops implies increased reliance on pollination services. Yet agricultural practices themselves can profoundly affect pollinator supply and pollination. Extensive monocultures are associated with a limited pollinator supply and reduced pollination, whereas agricultural diversification can enhance both. Therefore, areas where agricultural diversity has increased, or at least been maintained, may better sustain high and more stable productivity of pollinator-dependent crops. Given that >80% of all crops depend, to varying extents, on insect pollination, a global increase in agricultural pollinator dependence over recent decades might have led to a concomitant increase in agricultural diversification. We evaluated whether an increase in the area of pollinator-dependent crops has indeed been associated with an increase in agricultural diversity, measured here as crop diversity, at the global, regional, and country scales for the period 1961–2016. Globally, results show a relatively weak and decelerating rise in agricultural diversity over time that was largely decoupled from the strong and continually increasing trend in agricultural dependency on pollinators. At regional and country levels, there was no consistent relationship between temporal changes in pollinator dependence and crop diversification. Instead, our results show heterogeneous responses in which increasing pollinator dependence for some countries and regions has been associated with either an increase or a decrease in agricultural diversity. Particularly worrisome is a rapid expansion of pollinator-dependent oilseed crops in several countries of the Americas and Asia that has resulted in a decrease in agricultural diversity. In these regions, reliance on pollinators is increasing, yet agricultural practices that undermine pollination services are expanding. Our analysis has thereby identified world regions of particular concern where environmentally damaging practices associated with large-scale, industrial agriculture threaten key ecosystem services that underlie productivity, in addition to other benefits provided by biodiversity.Fil: Aizen, Marcelo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Aguiar, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; ArgentinaFil: Biesmeijer, Jacobus C.. Leiden University; Países Bajos. Naturalis Biodiversity Center; Países BajosFil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Sede Andina. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Inouye, David W.. University of Maryland; Estados Unidos. Rocky Mountain Biological Laboratory; Estados UnidosFil: Jung, Chuleui. Andong National University; Corea del SurFil: Martins, Dino J.. University of Princeton; Estados UnidosFil: Medel, Rodrigo. Universidad de Chile; ChileFil: Morales, Carolina Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Ngo, Hien. UN Campus Platz der Vereinten Nationen. Intergovernmental Science Policy Platform on Biodiversity and Ecosystem Services; AlemaniaFil: Pauw, Anton. Stellenbosch University; SudáfricaFil: Paxton, Robert J. Martin Luther University Halle Wittenberg; Alemania. German Centre for Integrative Biodiversity Research; AlemaniaFil: Sáez, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Seymour, Colleen L.. South African National Biodiversity Institute; Sudáfrica. University of Cape Town; Sudáfric

Distance-dependent association of affect with pacing strategy in cycling time trials.

The psychological construct of affect is proposed to significantly contribute to pacing decisions during exercise. Borg’s RPE scale, another important regulator of work rate, is criticized as an inadequate measure of the multiple perceptual responses experienced. This study aimed to examine power output distribution and associated changes in affect, self-efficacy, perceptual cues, HR, and respiratory gases during both 16.1- and 40-km self-paced cycling time trials (TT). Secondly, the differentiation between physical perceptions of exertion and sense of effort in self-paced exercise was investigated. Method: Fifteen trained male cyclists completed 16.1- and 40-km TT using a CompuTrainer cycle ergometer. Time, power output distribution, affect, self-efficacy, physical RPE (P-RPE), task effort and awareness (TEA), HR, and respiratory gases were measured throughout each TT. Linear mixed models explored associations of these variables with power output distribution and the relationship between P-RPE and TEA. Results: Similar pacing strategies were adopted in the 16.1- and 40-km TT (P = 0.31), and the main effects were found for affect (P = 0.001) and RER (P G 0.001). Interactions between affect (P = 0.037) and RER (P = 0.004), with condition, indicated closer associations with power output distribution in 16.1 km than that in 40 km TT. P-RPE was not significantly different from TEA (P = 0.053). Conclusion: A significant association between affect and power output distribution suggests that affective responses are task dependent even in self-paced exercise, and a greater association is demonstrated in higher intensity, 16.1 km TT. Furthermore, physical perceptions of exertion are not clearly differentiated from the sense of effort in self-paced exercise

Animal Welfare Attitudes: Effects of Gender and Diet in University Samples from 22 Countries

Animal Welfare Attitudes (AWA) are defined as human attitudes towards the welfare of animals in different dimensions and settings. Demographic factors, such as age and gender are associated with AWA. The aim of this study was to assess gender differences among university students in a large convenience sample from twenty-two nations in AWA. A total of 7914 people participated in the study (5155 women, 2711 men, 48 diverse). Participants completed a questionnaire that collected demographic data, typical diet and responses to the Composite Respect for Animals Scale Short version (CRAS-S). In addition, we used a measure of gender empowerment from the Human Development Report. The largest variance in AWA was explained by diet, followed by country and gender. In terms of diet, 6385 participants reported to be omnivores, 296 as pescatarian, 637 ate a vegetarian diet and 434 were vegans (n = 162 without answer). Diet was related with CRAS-S scores; people with a vegan diet scored higher in AWA than omnivores. Women scored significantly higher on AWA than men. Furthermore, gender differences in AWA increased as gender inequality decreased