A PROTOCOL OR A SET OF STANDARDS TO GUIDE AGRICULTURAL ECONOMICS RESEARCH

This article examines some difficult decisions that agricultural economists must confront in doing research. Over many years, rules and standards have developed in agricultural economics that guide researchers, providing an underlying framework for research methods. This article deals with applying these seldom discussed guidelines to specific research situations confronted by agricultural economists. With this article, we hope to stimulate a dialogue among agricultural economists about the need for additional, appropriate methodological guidelines in agricultural economics research.Research and Development/Tech Change/Emerging Technologies,

Family Law and Gay and Lesbian Family Issues in the Twentieth Century

Over these thirty years, lesbians and gay men have increasingly challenged conventional definitions of marriage and the family. In this brief article, we tell the story of gay people and family law in the United States across this period. We divide our discussion into two sections: issues regarding the recognition of the same-sex couple relationship and issues regarding gay men and lesbians as parents. These issues overlap, of course, but since family law discussions commonly treat adult-adult issues of all sorts separately from parent-child issues, we believe it convenient and helpful to do so as well

Predicting the movements of permanently installed electrodes on an active landslide using time-lapse geoelectrical resistivity data only

If electrodes move during geoelectrical resistivity monitoring and their new positions are not incorporated in the inversion, then the resulting tomographic images exhibit artefacts that can obscure genuine time-lapse resistivity changes in the subsurface. The effects of electrode movements on time-lapse resistivity tomography are investigated using a simple analytical model and real data. The correspondence between the model and the data is sufficiently good to be able to predict the effects of electrode movements with reasonable accuracy. For the linear electrode arrays and 2D inversions under consideration, the data are much more sensitive to longitudinal than transverse or vertical movements. Consequently the model can be used to invert the longitudinal offsets of the electrodes from their known baseline positions using only the time-lapse ratios of the apparent resistivity data. The example datasets are taken from a permanently installed electrode array on an active lobe of a landslide. Using two sets with different levels of noise and subsurface resistivity changes, it is found that the electrode positions can be recovered to an accuracy of 4 % of the baseline electrode spacing. This is sufficient to correct the artefacts in the resistivity images, and provides for the possibility of monitoring the movement of the landslide and its internal hydraulic processes simultaneously using electrical resistivity tomography only

Hypothalamic Vitamin D Improves Glucose Homeostasis and Reduces Weight

Despite clear associations between vitamin D deficiency and obesity and/or type 2 diabetes, a causal relationship is not established. Vitamin D receptors (VDRs) are found within multiple tissues, including the brain. Given the importance of the brain in controlling both glucose levels and body weight, we hypothesized that activation of central VDR links vitamin D to the regulation of glucose and energy homeostasis. Indeed, we found that small doses of active vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3) (calcitriol), into the third ventricle of the brain improved glucose tolerance and markedly increased hepatic insulin sensitivity, an effect that is dependent upon VDR within the paraventricular nucleus of the hypothalamus. In addition, chronic central administration of 1,25D3 dramatically decreased body weight by lowering food intake in obese rodents. Our data indicate that 1,25D3-mediated changes in food intake occur through action within the arcuate nucleus. We found that VDR colocalized with and activated key appetite-regulating neurons in the arcuate, namely proopiomelanocortin neurons. Together, these findings define a novel pathway for vitamin D regulation of metabolism with unique and divergent roles for central nervous system VDR signaling. Specifically, our data suggest that vitamin D regulates glucose homeostasis via the paraventricular nuclei and energy homeostasis via the arcuate nuclei

How good was the profitability of British Railways, 1870-1912?

This paper provides new estimates of the return on capital employed (ROCE) for major British railway companies. It shows that ROCE was generally below the cost of capital after the mid-1870s and fell till the turn of the century. Addressing issues of cost inefficiency could have restored ROCE to an adequate level in the late 1890s but not in 1910. Declines in ROCE hit share prices and returns to shareholders were negative after 1897. Optimal portfolio analysis shows that, whilst railway securities would have had a substantial weight prior to this date, investors would have been justified in rushing to the exits thereafter

Water as a Factor in Energy Resources Development

Water, in many cases, is a key factor in the development of energy resources in the western states. The total water supply available in the arid west is fixed; yet potential water uses in the region are growing continually. In fact, in many areas quantities of water desired to be put to beneficial use has already surpassed the limit of local supplies as indicated by filings for water rights. The availability of water, in adequate quantities and of suitable quality, is one of the essentials to the economic viability of some economic sectors in the states in the Colorado River Basin. Many existing water uses are already under economic pressure which could shift water to users who can afford to pay higher prices. With the entire region undergoing an energy boom, Duchesne and Uintah Counties, which are agriculture oriented, for example, may see water bought from agriculture for energy development

DNA fingerprinting in zoology: past, present, future

In 1962, Thomas Kuhn famously argued that the progress of scientific knowledge results from periodic 'paradigm shifts' during a period of crisis in which new ideas dramatically change the status quo. Although this is generally true, Alec Jeffreys' identification of hypervariable repeat motifs in the human beta-globin gene, and the subsequent development of a technology known now as 'DNA fingerprinting', also resulted in a dramatic shift in the life sciences, particularly in ecology, evolutionary biology, and forensics. The variation Jeffreys recognized has been used to identify individuals from tissue samples of not just humans, but also of many animal species. In addition, the technology has been used to determine the sex of individuals, as well as paternity/maternity and close kinship. We review a broad range of such studies involving a wide diversity of animal species. For individual researchers, Jeffreys' invention resulted in many ecologists and evolutionary biologists being given the opportunity to develop skills in molecular biology to augment their whole organism focus. Few developments in science, even among the subsequent genome discoveries of the 21st century, have the same wide-reaching significance. Even the later development of PCR-based genotyping of individuals using microsatellite repeats sequences, and their use in determining multiple paternity, is conceptually rooted in Alec Jeffreys' pioneering work

Addendum to "Coherent radio pulses from GEANT generated electromagnetic showers in ice"

We reevaluate our published calculations of electromagnetic showers generated by GEANT 3.21 and the radio frequency pulses they produce in ice. We are prompted by a recent report showing that GEANT 3.21-modeled showers are sensitive to internal settings in the electron tracking subroutine. We report the shower and pulse characteristics obtained with different settings of GEANT 3.21 and with GEANT 4. The default setting of electron tracking in GEANT 3.21 we used in previous work speeds up the shower simulation at the cost of information near the end of the tracks. We find that settings tracking electron and positron to lower energy yield a more accurate calculation, a more intense shower, and proportionately stronger radio pulses at low frequencies. At high frequencies the relation between shower tracking algorithm and pulse spectrum is more complex. We obtain radial distributions of shower particles and phase distributions of pulses from 100 GeV showers that are consistent with our published results.Comment: 4 pages, 3 figure