The dairy industry in the developed world has undergone profound changes over recent decades. In this paper, we present an overview of some of the most important recent changes in the dairy industry ...that affect health and welfare of dairy cows, as well as the science associated with these changes. Additionally, knowledge gaps are identified where research is needed to guide the dairy industry through changes that are occurring now or that we expect will occur in the future. The number of farms has decreased considerably, whereas herd size has increased. As a result, an increasing number of dairy farms depend on hired (nonfamily) labor. Regular professional communication and establishment of farm-specific protocols are essential to minimize human errors and ensure consistency of practices. Average milk production per cow has increased, partly because of improvements in nutrition and management but also because of genetic selection for milk production. Adoption of new technologies (e.g., automated calf feeders, cow activity monitors, and automated milking systems) is accelerating. However, utilization of the data and action lists that these systems generate for health and welfare of livestock is still largely unrealized, and more training of dairy farmers, their employees, and their advisors is necessary. Concurrently, to remain competitive and to preserve their social license to operate, farmers are increasingly required to adopt increased standards for food safety and biosecurity, become less reliant on the use of antimicrobials and hormones, and provide assurances regarding animal welfare. Partly because of increasing herd size but also in response to animal welfare regulations in some countries, the proportion of dairy herds housed in tiestalls has decreased considerably. Although in some countries access to pasture is regulated, in countries that traditionally practiced seasonal grazing, fewer farmers let their dairy cows graze in the summer. The proportion of organic dairy farms has increased globally and, given the pressure to decrease the use of antimicrobials and hormones, conventional farms may be able to learn from well-managed organic farms. The possibilities of using milk for disease diagnostics and monitoring are considerable, and dairy herd improvement associations will continue to expand the number of tests offered to diagnose diseases and pregnancy. Genetic and genomic selection for increased resistance to disease offers substantial potential but requires collection of additional phenotypic data. There is every expectation that changes in the dairy industry will be further accentuated and additional novel technologies and different management practices will be adopted in the future.
Prostate cancer affects a major proportion of older men, and effective preventive measures are few. Earlier suggestions of 10-30% risk reduction from vigorous physical activity thus merit further ...analysis. This narrative review updates information on associations between physical activity and prostate cancer, seeking activity patterns associated with maximal risk reduction. Systematic searches of Ovid/MEDLINE and PubMed databases from 1996 to June 2016 have linked the terms prostate neoplasms/prostate cancer with occupation, occupational title, sedentary job or heavy work, exercise, physical activity, sports, athletes, physical education/training or aerobic fitness. Combining these searches with findings from earlier reviews, 85 analyses were captured, although three were repeat analyses of the same data set. Seven analyses reported increased risk, and a further 31 showed no clear relationship. However, 24 analyses found a trend to diminished risk, and 21 a significant decrease (10-30% or more) in at least some subject subsets. Benefit was seen more consistently in occupational than in leisure studies, usually with adolescence or the early 20 s as the optimal age for preventive activity. In general, benefit showed a dose-response relationship, with vigorous activity required for maximal effect. Furthermore, several recent observational studies have indicated that physical activity is beneficial in preventing disease recurrence and improving survival following the diagnosis and treatment of prostate cancer. Despite continued research, conclusive proof of an association between regular physical activity and a low risk of prostate cancer remains elusive. However, reports that exercise exacerbates risk are few, and despite issues around controls, covariates, and co-morbidities, an impressive number of studies have now found significant benefit, suggesting that regular physical activity is important in terms of disease development, progression, and therapy. Given also the many other health benefits of an active lifestyle, it can be recommended as a potentially useful measure in the prevention of prostate cancer.
Accurate closed-loop control of continuum manipulators requires integration of both models that describe their motion and methods to evaluate manipulator shape. This work presents a model that ...approximates the continuous shape of a continuum manipulator by a serial chain of rigid links, connected by flexible rotational joints. This rigid-link model permits a description of manipulator shape under different loading conditions. A kinematic controller, based on the manipulator Jacobian of the proposed rigid-link model, is implemented and realizes trajectory tracking, while using the kinematic redundancy of the manipulator to perform a secondary task of avoiding obstacles. The controller is evaluated on an experimental testbed, consisting of a planar tendon-driven continuum manipulator with two bending segments. Fiber Bragg grating (FBG) sensors are used to reconstruct 3-D manipulator shape, and is used as feedback for closed-loop control of the manipulator. Manipulator steering is evaluated for two cases: the first case involving steering around a static obstacle and the second case involving steering along a straight path while avoiding a moving obstacle. Mean trajectory tracking errors are 0.24 and 0.09 mm with maximum errors of 1.37 and 0.52 mm for the first and second cases, respectively. Finally, we demonstrate the possibility of FBG sensors to measure interaction forces, while simultaneously using them for shape sensing.
The Mediterranean diet (MD) has been found to lower the risk of heart disease, stroke, and diabetes in adults. Little is known about its acceptance and relationship to cardiovascular risk markers in ...US adolescents. Using data from the National Health and Nutrition Examination Survey, years 2007-2014, we performed a cross-sectional analysis of adherence to the Mediterranean diet among a representative sample of US adolescents (n = 4223), factors that influence adherence, and whether adherence is associated with cardiometabolic risk factors including metabolic syndrome. MD adherence was calculated using the KIDMED scoring system. We found that overall MD adherence was very low among US adolescents, with Mexican American youths having higher adherence compared to other groups. Higher income was associated with greater adherence. There was low intake of key MD foods including olive oil and finfish. The unadjusted prevalence of metabolic syndrome was 6.6%. MD adherence was not associated with metabolic syndrome.
This title is part of UC Press's Voices Revived program, which commemorates University of California Press's mission to seek out and cultivate the brightest minds and give them voice, reach, and ...impact. Drawing on a backlist dating to 1893, Voices Revived makes high-quality, peer-reviewed scholarship accessible once again using print-on-demand technology. This title was originally published in 1962.
This paper advances a new theoretical model to understand the effect of culture on creativity in a global context. We theorize that creativity engagement and success depend on the cultural ...tightness—the extent to which a country is characterized by strong social norms and low tolerance for deviant behaviors—of both an innovator's country and the audience's country, as well as the cultural distance between these two countries. Using field data from a global online crowdsourcing platform that organizes creative contests for consumerproduct brands, supplemented by interviews with, marketing experts, we found that individuals from tight cultures are less likely than counterparts from loose cultures to engage in and succeed at foreign creative tasks; this effect is intensified as the cultural distance between the innovator's and the audience's country increases. Additionally, tight cultures are less receptive to foreign creative ideas. But we also found that in certain circumstances—when members of a tight culture do creative work in their own or culturally close countries—cultural tightness can actually promote creativity success. This finding implies that some degree of convergent thinking as engendered by tight cultures could be beneficial for creativity, challenging the dominant view in creativity research that divergent thinking is a prerequisite for creative performance.
An overview of a comprehensive framework is given for estimating the predictive uncertainty of scientific computing applications. The framework is comprehensive in the sense that it treats both types ...of uncertainty (aleatory and epistemic), incorporates uncertainty due to the mathematical form of the model, and it provides a procedure for including estimates of numerical error in the predictive uncertainty. Aleatory (random) uncertainties in model inputs are treated as random variables, while epistemic (lack of knowledge) uncertainties are treated as intervals with no assumed probability distributions. Approaches for propagating both types of uncertainties through the model to the system response quantities of interest are briefly discussed. Numerical approximation errors (due to discretization, iteration, and computer round off) are estimated using verification techniques, and the conversion of these errors into epistemic uncertainties is discussed. Model form uncertainty is quantified using (a) model validation procedures, i.e., statistical comparisons of model predictions to available experimental data, and (b) extrapolation of this uncertainty structure to points in the application domain where experimental data do not exist. Finally, methods for conveying the total predictive uncertainty to decision makers are presented. The different steps in the predictive uncertainty framework are illustrated using a simple example in computational fluid dynamics applied to a hypersonic wind tunnel.
Computational simulation can be defined as any computer application which involves the numerical solution to a system of partial differential equations. In this paper, a broad overview is given of ...verification procedures for computational simulation. The two aspects of verification examined are code verification and solution verification. Code verification is a set of procedures developed to find coding mistakes that affect the numerical discretization. The method of manufactured solutions combined with order of accuracy verification is recommended for code verification, and this procedure is described in detail. Solution verification is used to estimate the numerical errors that occur in every computational simulation. Both round-off and iterative convergence errors are discussed, and a posteriori methods for estimating the discretization error are examined. Emphasis is placed on discretization error estimation methods based on Richardson extrapolation as they are equally applicable to any numerical method. Additional topics covered include calculating the observed order of accuracy, error bands, and practical aspects of mesh refinement.
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