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Role of State Policy in Renewable Energy Development
State policies can support renewable energy development by driving markets, providing certainty in the investment market, and incorporating the external benefits of the technologies into cost/benefit calculations. Using statistical analyses and policy design best practices, this paper quantifies the impact of state-level policies on renewable energy development in order to better understand the role of policy on development and inform policy makers on the policy mechanisms that provide maximum benefit. The results include the identification of connections between state policies and renewable energy development, as well as a discussion placing state policy efforts in context with other factors that influence the development of renewable energy (e.g. federal policy, resource availability, technology cost, public acceptance)
Revising the Language Map of Korea
As linguists develop a deeper understanding of the properties of individual varieties of speech, they often find it necessary to reclassify dialects as independent languages, based on the criterion of intelligibility. This criterion is applied here to Jejueo, the traditional variety of speech used on Jeju Island, a province of the Republic of Korea. Although Jejueo has long been classified as a nonstandard dialect of Korean, evidence from an intelligibility experiment shows that it is not comprehensible to monolingual speakers of Korean and therefore should be treated as a separate language, in accordance with the usual practice within linguistics. This finding calls for a revision to the standard language map of Kore
Hydraulics Near Unscreened Diversion Pipes in Open Channels: Large Flume Experiments
Most of the water diversions on the Sacramento and San Joaquin Rivers (California, United States) and their tributaries are currently unscreened. These unscreened diversions are commonly used for irrigation and are potentially harmful to migrating and resident fishes. A large flume (test section: 18.29 m long, 3.05 m wide and 3.20 m high) was used to investigate the hydraulic fields near an unscreened water diversion under ecologically and hydraulically relevant diversion rates and channel flow characteristics. We investigated all combinations of three diversion rates (0.28, 0.42, and 0.57 m3/s) and three sweeping velocities (0.15, 0.38, and 0.61 m/s), with one additional test at 0.71 m3/s and 0.15 m/s. We measured the three-dimensional velocity field at seven cross sections near a diversion pipe and constructed regression equations of the observed maximum velocities near the pipe. Because the velocity components in three directions (longitudinal, transverse, and vertical) were significantly greater near the diversion pipe inlet compared with those farther from it, they cannot be neglected in the modeling and design of fish guidance and protection devices for diversion pipes. Our results should be of great value in quantifying the hydraulic fields that are formed around fish guidance devices to design more effective protection for fishes from entrainment into unscreened water-diversion pipes
Le gisement pléistocène moyen de Galeria Pesada (Estrémadure, Portugal) : premiers résultats
Les fouilles de la grotte de Galeria Pesada (complexe karstique d’Almonda, Torres Novas) livrent de riches assemblages lithiques et osseux datés du Pléistocène moyen final (fouilles 1997-1999). Les ensembles lithiques sont caractérisés par une combinaison d’outils classiques de l’Acheuléen, d’une abondante série d’outils bifaciaux (foliacés, petits bifaces asymétriques, Keilmesser, etc.) et de nombreux racloirs, souvent en quartz. Cette industrie n’a pas d’équivalent jusqu’à présent dans la Péninsule ibérique. Elle est associée à une faune dominée par les Cervidés et les Equidés dont les ossements présentent un fort pourcentage de marques de boucherie, démontrant une exploitation intensive (consommation) des carcasses par les anciens hominidés.Excavations at the late Middle Pleistocene cave site of Galeria Pesada in Portuguese Estremadura have uncovered a series of lithic assemblages associated with abundant faunal remains (Excavations 1997-1999). The lithic assemblages are all similar and consist of a combination of a few classic Acheulean tools, a rich series of bifacial tools (foliates, small asymmetric bifaces, Keilmesser, etc.), and a large number of scrapers, often on quartz. These assemblages, unknown to date in the rest of Iberia, are associated with Cervids and Equids, cut marks on bones indicate extensive and intensive carcass modification and consumption by hominids
Taphonomic Criteria for Identifying Iberian Lynx Dens in Quaternary Deposits
For decades, taphonomists have dedicated their efforts to assessing the nature of the massive leporid accumulations recovered at archaeological sites in the northwestern Mediterranean region. Their interest lying in the fact that the European rabbit constituted a critical part of human subsistence during the late Pleistocene and early Holocene. However, rabbits are also a key prey in the food webs of Mediterranean ecosystems and the base of the diet for several specialist predators, including the Iberian lynx (Lynx pardinus). For this reason, the origin of rabbit accumulations in northwestern Mediterranean sites has proved a veritable conundrum. Here, we present the zooarchaeological and taphonomic study of more than 3000 faunal and 140 coprolite remains recovered in layer IIIa of Cova del Gegant (Catalonia, Spain). Our analysis indicates that this layer served primarily as a den for the Iberian lynx. The lynxes modified and accumulated rabbit remains and also died at the site creating an accumulation dominated by the two taxa. However, other agents and processes, including human, intervened in the final configuration of the assemblage. Our study contributes to characterizing the Iberian lynx fossil accumulation differentiating between the faunal assemblages accumulated by lynxes and hominins
Addition of meloxicam to the treatment of clinical mastitis improves subsequent reproductive performance
AbstractA blinded, negative controlled, randomized intervention study was undertaken to test the hypothesis that addition of meloxicam, a nonsteroidal anti-inflammatory drug, to antimicrobial treatment of mild to moderate clinical mastitis would improve fertility and reduce the risk of removal from the herd. Cows (n=509) from 61 herds in 8 regions (sites) in 6 European countries were enrolled. Following herd-owner diagnosis of mild to moderate clinical mastitis within the first 120d of lactation in a single gland, the rectal temperature, milk appearance, and California Mastitis Test score were assessed. Cows were randomly assigned within each site to be treated either with meloxicam or a placebo (control). All cows were additionally treated with 1 to 4 intramammary infusions of cephalexin and kanamycin at 24-h intervals. Prior to treatment and at 14 and 21d posttreatment, milk samples were collected for bacteriology and somatic cell count. Cows were bred by artificial insemination and pregnancy status was subsequently defined. General estimating equations were used to determine the effect of treatment (meloxicam versus control) on bacteriological cure, somatic cell count, the probability of being inseminated by 21d after the voluntary waiting period, the probability of conception to first artificial insemination, the number of artificial insemination/conception, the probability of pregnancy by 120 or 200d postcalving, and the risk of removal by 300d after treatment. Cox’s proportional hazards models were used to test the effect of treatment on the calving to first insemination and calving to conception intervals. Groups did not differ in terms of age, clot score, California Mastitis Test score, rectal temperature, number of antimicrobial treatments given or bacteria present at the time of enrollment, but cows treated with meloxicam had greater days in milk at enrollment. Cows treated with meloxicam had a higher bacteriological cure proportion than those treated with the placebo [0.66 (standard error=0.04) versus 0.50 (standard error=0.06), respectively], although the proportion of glands from which no bacteria were isolated posttreatment did not differ between groups. No difference was observed in the somatic cell count between groups pre- or posttreatment. The proportion of cows that underwent artificial insemination by 21d after the voluntary waiting period was unaffected by treatment. Treatment with meloxicam was associated with a higher proportion of cows conceiving to their first artificial insemination (0.31 versus 0.21), and a higher proportion of meloxicam-treated cows were pregnant by 120d after calving (0.40 versus 0.31). The number of artificial inseminations required to achieve conception was lower in the meloxicam compared with control cows (2.43 versus 2.92). No difference was observed between groups in the proportion of cows pregnant by 200d after calving or in the proportion of cows that were culled, died, or sold by 300d after calving (17% versus 21% for meloxicam versus control, respectively). It was concluded that use of meloxicam, in conjunction with antimicrobial therapy, for mild to moderate cases of clinical mastitis, resulted in a higher probability of bacteriological cure, an increased probability of conception to first artificial insemination, fewer artificial inseminations, and a greater proportion of cows pregnant by 120d in milk
Live cell dynamics of production, explosive release and killing activity of phage tail-like weapons for Pseudomonas kin exclusion.
Interference competition among bacteria requires a highly specialized, narrow-spectrum weaponry when targeting closely-related competitors while sparing individuals from the same clonal population. Here we investigated mechanisms by which environmentally important Pseudomonas bacteria with plant-beneficial activity perform kin interference competition. We show that killing between phylogenetically closely-related strains involves contractile phage tail-like devices called R-tailocins that puncture target cell membranes. Using live-cell imaging, we evidence that R-tailocins are produced at the cell center, transported to the cell poles and ejected by explosive cell lysis. This enables their dispersal over several tens of micrometers to reach targeted cells. We visualize R-tailocin-mediated competition dynamics between closely-related Pseudomonas strains at the single-cell level, both in non-induced condition and upon artificial induction. We document the fatal impact of cellular self-sacrifice coupled to deployment of phage tail-like weaponry in the microenvironment of kin bacterial competitors, emphasizing the necessity for microscale assessment of microbial competitions
Beyond word frequency: Bursts, lulls, and scaling in the temporal distributions of words
Background: Zipf's discovery that word frequency distributions obey a power
law established parallels between biological and physical processes, and
language, laying the groundwork for a complex systems perspective on human
communication. More recent research has also identified scaling regularities in
the dynamics underlying the successive occurrences of events, suggesting the
possibility of similar findings for language as well.
Methodology/Principal Findings: By considering frequent words in USENET
discussion groups and in disparate databases where the language has different
levels of formality, here we show that the distributions of distances between
successive occurrences of the same word display bursty deviations from a
Poisson process and are well characterized by a stretched exponential (Weibull)
scaling. The extent of this deviation depends strongly on semantic type -- a
measure of the logicality of each word -- and less strongly on frequency. We
develop a generative model of this behavior that fully determines the dynamics
of word usage.
Conclusions/Significance: Recurrence patterns of words are well described by
a stretched exponential distribution of recurrence times, an empirical scaling
that cannot be anticipated from Zipf's law. Because the use of words provides a
uniquely precise and powerful lens on human thought and activity, our findings
also have implications for other overt manifestations of collective human
dynamics
Noncomparabilities & Non Standard Logics
Many normative theories set forth in the welfare economics, distributive justice and cognate literatures posit noncomparabilities or incommensurabilities between magnitudes of various kinds. In some cases these gaps are predicated on metaphysical claims, in others upon epistemic claims, and in still others upon political-moral claims. I show that in all such cases they are best given formal expression in nonstandard logics that reject bivalence, excluded middle, or both. I do so by reference to an illustrative case study: a contradiction known to beset John Rawls\u27s selection and characterization of primary goods as the proper distribuendum in any distributively just society. The contradiction is avoided only by reformulating Rawls\u27s claims in a nonstandard form, which form happens also to cohere quite attractively with Rawls\u27s intuitive argumentation on behalf of his claims
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