9,023 research outputs found
The Legal Framework for States as Employers-of-Choice in Workplace Flexibility: A Case Study of Arizona and Michigan
Outlines the statutes, regulations, executive actions, and collective bargaining agreements that authorize flexible work arrangements, time off, and career flexibility in the two state workforces; the elements of model programs; and their benefits
Perturbative extension of the standard model with a 125 GeV Higgs and Magnetic Dark Matter
We introduce a perturbative extension of the standard model featuring a new
dark matter sector together with a 125 GeV Higgs. The new sector consists of a
vector-like heavy electron E, a complex scalar electron S and a standard model
singlet Dirac fermion \chi. The interactions among the dark matter candidate
\chi and the standard model particles occur via loop-induced processes
involving the operator SE\chi y, with y being the Yukawa-like coupling. The
model is an explicit underlying realization of the light magnetic dark matter
effective model introduced earlier to alleviate the tension among several
direct dark matter search experiments. We further constrain the parameters of
the underlying theory using results from the Large Hadron Collider. The
extension can accommodate the recently observed properties of the Higgs-like
state and leads to interesting predictions. Finally we show that the model's
collider phenomenology and constraints nicely complement the ones coming from
dark matter searches.Comment: Final version to match the one published in Phys. Rev.
Determination of the universality class of crystal plasticity
Although scaling phenomena have long been documented in crystalline
plasticity, the universality class has been difficult to identify due to the
rarity of avalanche events, which require large system sizes and long times in
order to accurately measure scaling exponents and functions. Here we present
comprehensive simulations of two-dimensional dislocation dynamics under shear,
using finite-size scaling to extract scaling exponents and the avalanche
profile scaling function from time-resolved measurements of slip-avalanches.
Our results provide compelling evidence that both the static and dynamic
universality classes are consistent with the mean-field interface depinning
model.Comment: 6 pages, 4 figures. Figure 4 inset has been corrected as compared to
the EPL publication. We thank Michael Zaiser for bringing its incorrect
caption to our attention. The correction leaves all results unaffecte
Seasonality in the Irish dairy processing industry
The dairy landscape in the Republic of Ireland is characterized by pastoral spring-calving systems and a bell-shaped milk production curve. This seasonality at producer level initiates various implications at processor level, such as poor utilization of plant capacity off-peak season, a requirement for seasonal labour management and limited product options in autumn and winter months due to the properties of late-lactation milk. An optimization model was developed to analyze the impact of production seasonality and quota removal on the Irish dairy processing industry in terms of maximum processor gross surplus, the optimum product mix and the marginal values of the milk solids fat, protein and lactose. Processor gross surplus was specified as a function of product sales revenue, less variable costs of collecting and processing raw milk and general overhead (fixed) costs. 5 scenarios with differing milk intake curves were examined whereby a flatter intake curve incurred less monthly variation in the marginal producer milk price, capacity utilization and product mix as well as a higher surplus as compared to more seasonal patterns. However, an isolated consideration of financial indicators at processor level disregards key characteristics of Irish grass-based seasonal milk production and producer-processor interdependencies. It was therefore concluded that a broader modelling approach integrating both the producer and the processor perspectives is desirable for more holistic analysis of sector-wide implications.Dairy processing, seasonality, milk quota abolition, processor profit, product mix, Farm Management, Livestock Production/Industries,
Herd-level risk factors associated with cow mortality in Swedish dairy herds
An increase in on-farm mortality (euthanasia and death) in dairy herds has been reported in several countries in the last decade. This does not only imply possible problems with animal welfare, but it also causes economic losses to the farmer. The objective of this study was to evaluate time trends in on-farm dairy cow mortality in Sweden and identify potential herd-level risk factors. Data was retrieved on all Swedish dairy herds enrolled in the milk recording scheme between 2002 and 2010. Herds with a herd size of 40 dead or euthanized cows per 100 cow-years were excluded. Two different models were used: 1 multiple year analysis which included 6,898 herds during the period 2002 to 2010 and 1 single year analysis including 4,252 herds for the year 2010, where other variables that were not present during the entire multiple year study were analyzed. The outcome variable was the number of euthanized and dead cows per year and season. A negative binomial regression model, adjusted for clustering within herd, was applied to both models. Fixed effects in the multiple year analysis were breed, calving interval, herd size, milk yield, region, season, pasture period, and year. Fixed effects in the single year analysis were breed, calving interval, conventional vs. organic farming, herd size, housing system, milk yield, region, and season. The multiple year analysis demonstrated that MR gradually increased from 5.1 to 6.6 events per 100 cow-years during the study period. Swedish MR are consequently on par with, or even greater than, MR among dairy herds in other comparable countries. Higher mortality was associated with larger herd size, longer calving intervals, and herds that had Swedish Holstein as the predominant breed. Lower mortality was observed in herds with a higher herd average milk yield, during the fall and winter, and in organically managed herds. There were regional differences in mortality. An interaction between herd size and season was found in both models. Also, an interaction between housing system and milk yield was found in the single year analysis. This first assessment of on-farm mortality in Swedish dairy herds confirmed that the MR has increased over the last few years. The study also identified some herd-level risk factors
Undervisning i kritisk tenkning: Autonomi til Ä bruke billedbÞker til undervisning i smÄskolen og pÄ mellomtrinnet.
This project addresses whether in-service teachers and pre-service teachers feel they have the agency to utilize picture books to promote critical thinking, with a particular focus on 4th and 5th grade. A total of six interviews were conducted; a small group of pre-service teachers and a pair of teachers were interviewed three times. Each interview featured a different picture book with a different theme, but they also included more general questions, ranging from teacher agency to defining critical thinking. The results indicate that the use of picture books is currently somewhat limited in the English classroom, while elements of critical literacy was more often included. The pre-service teachers also had a more positive attitude towards teaching critical thinking, while the teachers equally emphasised the importance of vocabulary and grammar, noting that elements of critical thinking were already implicitly present in many aspects of their normal teaching practice. While previous research also suggests that the use of picture books can motivate learners to share viewpoints on meaningful issues, this study suggests that the use of picture books can be an inclusive entryway to learning the necessary vocabulary to discuss the themes within the books in light of critical thinking
Abundance, distribution, and habitat of leatherback turtles (Dermochelys coriacea) off California, 1990â2003
Leatherback turtles (Dermochelys coriacea) are regularly seen off the U.S. West Coast, where they forage on jellyfish (Scyphomedusae) during summer and fall. Aerial line-transect surveys were conducted in neritic waters (<92 m depth) off central and northern California during 1990â2003, providing the first foraging population estimates for Pacific leatherback turtles. Males and females of about 1.1 to 2.1 m length were observed. Estimated abundance was linked to the Northern Oscillation Index and ranged from 12 (coefficient of variation [CV] =0.75) in 1995 to 379 (CV= 0.23) in 1990, averaging 178 (CV= 0.15). Greatest densities were found off central California, where oceanographic retention areas or upwelling shadows created favorable habitat for leatherback turtle prey. Results from independent telemetry studies have linked leatherback turtles off the U.S. West Coast to one of the two largest remaining Pacific breeding populations, at Jamursba Medi, Indonesia. Nearshore waters off California thus represent an important foraging region for the critically endangered Pacific leatherback turtle
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