Multidimensional Skills, Sorting, and Human Capital Accumulation

We construct a structural model of on-the-job search in which workers differ in skills along several dimensions and sort themselves into jobs with heterogeneous skill requirements along those same dimensions. Skills are accumulated when used, and depreciate when not used. We estimate the model combining data from O*NET with the NLSY79. We use the model to shed light on the origins and costs of mismatch along heterogeneous skill dimensions. We highlight the deficiencies of relying on a unidimensional model of skill when decomposing the sources of variation in the value of lifetime output between initial conditions and career shocks

Vurdering av metoder for økologisk produksjon av storfekjøtt. Fordeler og ulemper ved ulike produksjonssystemer for økologisk storfekjøtt.

På oppdrag fra Relelverksutvalget for økologisk produksjon (RVU) har Bioforsk utført en vurdering av fordeler og ulemper knyttet til luftekravet for okser i økologisk produksjon, samt en utredning av mulige løsninger for lufting av okser. I tillegg er det utført en vudering av alternative metoder for produksjon av økologisk storfekjøtt, for eksempel produksjon av kastrat-, kvige- og kalvekjøtt. Økologisk produksjon av storfekjøtt er vurdert med bakgrunn i kravet om lufting av okser. Regelverket for økologisk produksjon(EU-reg. 2091/92) sier at "(...) okser skal ha tilgang til beiter eller luftegårder. Okser over ett år gamle kan holdes i et husdyrrom med fri adgang til en luftegård hele året, i stedet for å gå på beite i sommerperioden." Nytt regelverk som vil bli gjeldende i løpet av 2011 (EU-reg 834/2007 og 889/2008) vil mest sannsynlig ha samme ordlyd. Tilgang på luftegård/større plass er positivt for helse og velferd hos storfe, og det finnes flere alternative og gode måter å oppstalle okser på som både tilfredsstiller dyrenes krav til lufting og mulighet for naturlig atferd, uten at det går på bekostning av produksjon og sikkerhet. Beitebasert kjøttproduksjon på kastrater, kviger og kalver kan være gode alternativer til kjøttproduksjon på okser. Slike produksjoner gir mulighet for å produsere kjøtt av god kvalitet på en bærekraftig måte samtidig som en hindrer gjengroing av kulturlandskapet. Hovedtanken bak økologisk kjøttproduksjon på storfe må være at produksjonen tar hensyn til det økologiske regelverket og IFOAM sine økologiske prinsipper. Produksjonen skal være miljøvennlig, tilpasset naturens kretsløp og økologiske balanse, samt ha fokus på god dyrevelferd. Hvilken produksjonsform den enkelte kjøttprodusenten velger avhenger av hva slags ressurser den enkelte produsent/gårdsbruk har tilgang på. Det er viktig at rådgivningstjenesten har oversikt over de alternative produksjonsformene og kommer med de riktige rådene for den enkelte besetningen

Antioxidant Supplementation in the Treatment of Aging-Associated Diseases

Oxidative stress is generally considered as the consequence of an imbalance between pro- and antioxidants species, which often results into indiscriminate and global damage at the organismal level. Elderly people are more susceptible to oxidative stress and this depends, almost in part, from a decreased performance of their endogenous antioxidant system. As many studies reported an inverse correlation between systemic levels of antioxidants and several diseases, primarily cardiovascular diseases, but also diabetes and neurological disorders, antioxidant supplementation has been foreseen as an effective preventive and therapeutic intervention for aging-associated pathologies. However, the expectations of this therapeutic approach have often been partially disappointed by clinical trials. The interplay of both endogenous and exogenous antioxidants with the systemic redox system is very complex and represents an issue that is still under debate. In this review a selection of recent clinical studies concerning antioxidants supplementation and the evaluation of their influence in aging-related diseases is analyzed. The controversial outcomes of antioxidants supplementation therapies, which might partially depend from an underestimation of the patient specific metabolic demand and genetic background, are presented

Pengembangan Media Berbasis Multimedia Interaktif Untuk Meningkatkan Pemahaman Siswa Man 2 Batu Materi Kingdom Animalia

Learning biology plays an important role in the educational process as well as the development of technology, because biology has an effort for human to generate interest in science and technology development.Various issues that arise in school in biology learning materials associated with the Kingdom Animalia and the material is very much difficult for students to understand and time limitations in the learning process. So there should be used development of teaching media to overcome this. The purpose of this study are: (1) to know the effectiveness of the implementation of teaching media development, (2) to know the level of students understanding by using the application of teaching media development. This type of research is development research or Research and Development (R & D). the development used is based on the development steps from Borg & Gall (1983) modified from Sukmadinata (2010) which includes three steps, namely: preliminary study, development and validation. To determine the effectiveness of the implementation of teaching media development is done by giving the questionnaire to students. To determine the level of students understanding performed pretest and posttest. The research was conducted on 28 March to 29 September 2013 at MAN 2 Batu Malang. The results of this development in the form of teaching media product Biology that has been through some trials and revisions of the experts and students. Based on the feasibility of media experts, subject matter experts, and students teaching media are stated that it is very viable and effective used in learning. Based on the experimental test on class treatment there was an increasing students\u27 understanding of the material of the Kingdom Animalia that is the average value before using the media (pretest) increased from 41.60 to 90.3 after using the media (posttest), while the control class average value before reading textbooks (pretest) increased from 48.80 to 68.60 (posttest) after reading the textbooks. Thus it can be stated that teacing media based interaktive multimedia is more effective in improving students\u27 understanding of X class of MAN 2 Malang on the Kingdom Animalia subject

The Nordic Maintenance Care Program - Time intervals between treatments of patients with low back pain: how close and who decides?

<p>Abstract</p> <p>Background</p> <p>The management of chiropractic patients with acute and chronic/persistent conditions probably differs. However, little is known on this subject. There is, for example, a dearth of information on maintenance care (MC). Thus it is not known if patients on MC are coerced to partake in a program of frequent treatments over a long period of time, or if they are actively involved in designing their own individualized treatment program.</p> <p>Objectives</p> <p>It was the purpose of this study to investigate how chiropractic patients with low back pain were scheduled for treatment, with special emphasis on MC. The specific research questions were: 1. How many patients are on maintenance care? 2) Are there specific patterns of intervals between treatments for patients and, if so, do they differ between MC patients and non-MC patients? 3. Who decides on the next treatment, the patient, the chiropractor or both, and are there any differences between MC patients and non-MC patients?</p> <p>Methods</p> <p>Chiropractic students, who during their summer holidays were observers in chiropractic clinics in Norway and Denmark, recorded whether patients were classified by the treating chiropractor as a MC-patient or not, dates for last and subsequent visits, and made a judgement on whether the patient or the chiropractor decided on the next appointment.</p> <p>Results</p> <p>Observers in the study were 16 out of 30 available students. They collected data on 868 patients from 15 Danish and 13 Norwegian chiropractors. Twenty-two percent and 26%, respectively, were classified as MC patients. Non-MC patients were most frequently seen within 1 week. For MC patients, the previous visit was most often 2-4 weeks prior to the actual visit, and the next appointment between 1 and 3 months. This indicates a gradual increase in intervals. The decision of the next visit was mainly made by the chiropractor, also for MC patients. However, the study samples of chiropractors appear not to be representative of the general Danish and Norwegian chiropractic profession and the patients may also have been non-representative.</p> <p>Conclusion</p> <p>There were two distinctly different patterns for the time period between visits for MC patients and non-MC patients. For non-MC patients, the most frequent interval between visits was one week and for MC patients, the period was typically between two weeks and three months. It was primarily the chiropractor who made the next visit-decision. However, these results can perhaps not be extrapolated to other groups of patients and chiropractors.</p

A High-Density Linkage Map of the Ancestral Diploid Strawberry, Fragaria iinumae, Constructed with Single Nucleotide Polymorphism Markers from the IStraw90 Array and Genotyping by Sequencing

Fragaria iinumae Makino is recognized as an ancestor of the octoploid strawberry species, which includes the cultivated strawberry, Fragaria ×ananassa Duchesne ex Rozier. Here we report the construction of the first high-density linkage map for F. iinumae. The F. iinumae linkage map (Fii map) is based on two high-throughput techniques of single nucleotide polymorphism (SNP) genotyping: the IStraw90 Array (hereafter “Array”), and genotyping by sequencing (GBS). The F2 generation mapping population was derived by selfing F. iinumae hybrid F1D, the product of a cross between two divergent F. iinumae accessions collected from Hokkaido, Japan. The Fii map consists of seven linkage groups (LGs) and has an overall length of 451.7 cM as defined by 496 loci populated by 4173 markers: 3280 from the Array and 893 from GBS. Comparisons with two versions of the Fragaria vesca ssp. vesca L. ‘Hawaii 4’ pseudo-chromosome (PC) assemblies reveal substantial conservation of synteny and colinearity, yet identified differences that point to possible genomic divergences between F. iinumae and F. vesca, and/or to F. vesca genomic assembly errors. The Fii map provides a basis for anchoring a F. iinumae genome assembly as a prerequisite for constructing a second diploid reference genome for Fragaria

Bethe approximation for self-interacting lattice trees

In this paper we develop a Bethe approximation, based on the cluster variation method, which is apt to study lattice models of branched polymers. We show that the method is extremely accurate in cases where exact results are known as, for instance, in the enumeration of spanning trees. Moreover, the expressions we obtain for the asymptotic number of spanning trees and lattice trees on a graph coincide with analogous expressions derived through different approaches. We study the phase diagram of lattice trees with nearest-neighbour attraction and branching energies. We find a collapse transition at a tricritical theta point, which separates an expanded phase from a compact phase. We compare our results for the theta transition in two and three dimensions with available numerical estimates.Comment: 10 pages, 3 figures, to be published in Europhysics Letter

Reply to Comment on " Universal Fluctuations in Correlated Systems"

Reply to the comment, cond-mat/0209398 by by N.W. Watkins, S.C. Chapman, and G. RowlandsComment: To appear In Physical Review Letter