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RFRP3 influences basal lamina degradation, cellular death, and progesterone secretion in cultured preantral ovarian follicles from the domestic cat.
The hypothalamic neuropeptide RFRP3 can suppress hypothalamic GnRH neuron activation and inhibit gonadotropin release from the anterior pituitary. RFRP3 is also produced locally in the ovary and can inhibit steroidogenesis and follicle development in many vertebrates. However, almost nothing is known about the presence and regulatory action of RFRP3 in gonads of any carnivore species. Such knowledge is important for developing captive breeding programs for endangered carnivores and for inhibiting reproduction in feral species. Using the domestic cat as a model, our objectives were to (1) demonstrate the expression of feline RFRP3 (fRFRP3) and its receptor in the cat ovary and (2) assess the influence of fRFRP3 on ovarian follicle integrity, survival, and steroidogenesis in vitro. We first confirmed that fRFRP3 and its receptors (NPFFR1 and NPFFR2) were expressed in cat ovaries by sequencing PCR products from ovarian RNA. We then isolated and cultured preantral ovarian follicles in the presence of 10 or 1 ”M fRFRP3 + FSH (1 ”g/mL). We recorded the percentage of morphologically viable follicles (basal lamina integrity) over 8 days and calculated percentage survival of follicles on Day 8 (using fluorescent markers for cell survival and death). Last, we quantified progesterone accumulation in media. 10 ”M fRFRP3 had no observable effect on viability, survival, or steroid production compared to follicles exposed to only FSH. However, 1 ”M fRFRP3 decreased the percentage of morphologically viable follicles and the percentage of surviving follicles on Day 8. At the same time, 1 ”M fRFRP3 increased the accumulation of progesterone in media. Our study shows, for the first time, direct action of RFRP3 on the follicle as a functional unit, and it is the first in a carnivore species. More broadly, our results support a conserved, inhibitory action of RFRP3 on ovarian follicle development and underscore the importance of comparative functional studies
How Cosmic Background Correlations at Large Angles Relate to Mass Autocorrelations in Space
The Sachs-Wolfe effect is known to produce large angular scale fluctuations
in the Cosmic Microwave Background Radiation (CMBR) due to gravitational
potential fluctuations. We show how the angular correlation function of the
CMBR can be expressed explicitly in terms of the mass autocorrelation function
in the Universe. We derive analytic expressions for the angular
correlation function and its multipole moments in terms of integrals over or its second moment, , which does not need to satisfy the sort
of integral constraint that must. We derive similar expressions for
bulk flow velocity in terms of and . One interesting result that
emerges directly from this analysis is that, for angles , there is a
substantial contribution to the correlation function from a wide range of
distance and that the radial shape of this contribution does not vary
greatly with angle.Comment: 9 pages in Plain TeX and 6 figures appended in 9 pages of uuencoded
PostScript. Lick Preprint Number 1
A Preliminary Analysis of the Benefits of Introducing Apomixis into Rice
The objective of this research is to undertake an ex ante economic analysis of basic scientific research that aims to identify the gene(s) that control apomictic reproduction, with the ultimate aim of transferring the characteristic into commercially important crops. This paper reports very preliminary results, using the introduction of apomixis into rice as a case study. Apomixis is a natural, asexual method of plant reproduction resulting in offspring that are genetically identical to the mother plant. Apomixis promises to revolutionize plant breeding by providing a system for crop improvement that allows any desired variety, including hybrids, to breed true. This ability will make both breeding and seed production more efficient. It offers the opportunity for plant breeders to more readily develop varieties that are specifically adapted to local conditions, using, and thus conserving, greater genetic diversity. Apomixis will also allow resource-poor farmers to replant the seed they produce from locally bred varieties year after year, a strategy not possible with today's commercial hybrid varieties. Global changes in aggregate welfare, resource allocation, production and price levels are calculated using the global economy-wide computable general equilibrium model known as GTAP. Preliminary modeling results suggest that the overall welfare gains associated apomictic rice could be substantial.Agribusiness, Agricultural and Food Policy, Crop Production/Industries, Environmental Economics and Policy, Farm Management, Institutional and Behavioral Economics, Land Economics/Use, Production Economics, Research Methods/ Statistical Methods,
Knowledge discovery for friction stir welding via data driven approaches: Part 1 â correlation analyses of internal process variables and weld quality
For a comprehensive understanding towards Friction Stir Welding (FSW) which would lead to a unified approach that embodies materials other than aluminium, such as titanium and steel, it is crucial to identify the intricate correlations between the controllable process conditions, the observable internal process variables, and the characterisations of the post-weld materials. In Part I of this paper, multiple correlation analyses techniques have been developed to detect new and previously unknown correlations between the internal process variables and weld quality of aluminium alloy AA5083. Furthermore, a new exploitable weld quality indicator has, for the first time, been successfully extracted, which can provide an accurate and reliable indication of the âas-weldedâ defects. All results relating to this work have been validated using real data obtained from a series of welding trials that utilised a new revolutionary sensory platform called ARTEMIS developed by TWI Ltd., the original inventors of the FSW process
Army reserve prior service market profile
Only about 28 percent of the 177,023 enlisted losses to the Active Army in FY 1993 either transferred to the Reserve Components (RC) or had completed all of their obligated service and were eligible for reserve service (RE). Of these 48,000 RC and RE losses, 41,000 were in paygrades E4 and E5, the target pool for USAR Troop Program Unit (TPU) prior service recruiting. Only 28 percent of RC and RE E4--E5s had an occupation considered a priority for TPU readiness. A typical Active Army loss to the RC was a single white male E4 from the South census region with almost four years of service. He was a high school graduate in mental group category I-IIIA and had initially entered the Army for a four year term. A typical RE loss was a white male E5 with nine years of service. He was older and more likely to be married with dependents, but was similar in other respects to his RC counterpart. Neither was in a reserve priority occupation. Women made up less than 20 percent of both groups. Blacks were more strongly represented and Hispanics less strongly represented among RC and RE losses than among the comparable civilian population.Fund number: MIPR 7UNPSRSApproved for public release; distribution is unlimited
Assessing Domestic Demand for Organic and âLocally Grown' Produce on An âOrganic Island': Dominica's Dilemma
The economy of Dominica faces a unique set of challenges. As with many other Caribbean nations, Dominica has historically been dependent upon agriculture. Over the past several hundred years, the island's economy has been largely supported through the concentrated mono-cropping of a variety of export-oriented crops including coffee, limes, vanilla, and bananas (FAVACA, 2008). Today, approximately 45% of Dominica's labor force is employed in the agricultural sector (FAVACA, 2008). While neighboring countries have economically benefited from tourism, due to its lack of white sand beaches, Dominica is not a typical tourist destination. Taking advantage of its landscape, rainforests, and diversity of natural wildlife, in an effort to diversify its economy Dominica has instead catered to eco-/wellness tourists. Bridging its agricultural foundations with the ecological preservation needed to support its tourist industry, the government of Dominica has signaled its interest in transforming Dominica into an Organic Island (âOrganic Dominica') by 2015. Through this initiative, sustainable, organic agricultural production methods will be encouraged. Complementing this, a âBuy Organic, Locally Grown' campaign has been proposed to encourage domestic and regional consumption of Dominica's agricultural outputs and food products. As such, âOrganic Dominica' has the potential to simultaneously address ongoing national concerns surrounding food security, foreign exchange availability, domestic un/underemployment, and environmental preservation. Before and since proposing this policy, surveys were conducted to identity the major stakeholders in (organic) agricultural production, and current and potential markets for organic production. It remains, however, to quantify Dominica's capacity to produce organic goods, the scale of the potential market, and the price premia that organic production could command. This information is critical to determining the appropriate initial level of producer support and marketing programs required to successfully promote the production and consumption of Dominica's organic outputs and propel Dominica toward the desired status of a model âOrganic Island'.contingent valuation, willingness to pay, Caribbean, organic, locally grown, food, Agricultural and Food Policy, International Development, Marketing, O13, O54, Q01, Q13, Q18,
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