Phylogenetics of Apomictic Common Dallisgrass (Paspalum Dilatatum)

Common dallisgrass, Paspalum dilatatum Poir., an important warm season forage grass, is an obligate apomict with 50 chromosomes which associate as 20 bivalents and 10 univalents during meiosis. Because efforts to improve the grass have not been successful, a phylogenetic investigation was initiated to identify the progenitors of common dallisgrass in an effort to circumvent the apomictic barrier to improvement. The genomic composition has been determined for four dallisgrass biotypes: yellow-anthered (2n=4x=40) IIJJ; common (2n=5x=50) IIJJX; Uruguayan (2n=6x=60) IIJJXX; and Uruguaiana (2n=6x=60) IIJJXX. While the source of the X genome is unknown, the genes controlling apomixis are on at least one of the X chromosomes because biotypes with 10 or more X chromosomes are apomictic. However, when four or five of the X chromosomes are missing, apomixis is not expressed. This suggests that apomixis is controlled by more than one gene and at least one of the X chromosomes must be present for apomixis to be expressed

Fitness of Apomictic and Sexual Buffelgrass Germplasm

Breeding apomictic grasses is based on either the direct selection of apomictic landraces or the hybridization of sexual and apomictic types and selection of apomictic F1 hybrids. Little is known about the potential of sexual hybrids as cultivars in apomictic species. To determine if method of reproduction (MOR) was related to plant vigor, parental, S1, and F1 hybrids of buffelgrass differing in method of reproduction (apomictic or sexual) were established in a common garden in 1994 and 1995. In both years severe inbreeding depression was observed in the S1 progeny as they were shorter, produced less biomass, and had low seed-set when compared to the sexual parents or the F 1 hybrids. In contrast, the apomictic and sexual F1 hybrids produced similar biomass, tiller numbers, and were similar in plant height. This study suggests that while severe inbreeding depression occurs in buffelgrass, sexual F1 hybrids are as vigorous as apomictic hybrids and could be considered for potential use as cultivars

Buffelgrass Forage and Seed Production Responses to N and Fertilization

Forage and seed production responses to nitrogen (N) and phosphorus (P) fertilizer of Common buffelgrass (Cenchrus ciliaris L.) were evaluated for three years (1991-93). An incomplete factorial set of five rates of N and P were applied each year. Seed data were collected by hand stripping mature seed followed by a forage harvest. Seed quality characteristics were determined on each seed sample. No response to N fertilizer was observed in 1991 nor to P in any year. In 1992, there was a linear forage yield response to N fertilizer. In 1993, both the linear and quadratic effects of N fertilizer were significant. There was no consistent fertilizer response for any seed trait. Seed yields were higher in spring than autumn harvests. Mean weight per caryopsis declined with time of the year. Number of caryopsis per 100 involucres was greater in the spring/early summer than autumn and mid-May was greater than mid-June

A simplified model of aerosol removal by natural processes in reactor containments

Simplified formulae are developed for estimating the aerosol decontamination that can be achieved by natural processes in the containments of pressurized water reactors and in the drywells of boiling water reactors under severe accident conditions. These simplified formulae were derived by correlation of results of Monte Carlo uncertainty analyses of detailed models of aerosol behavior under accident conditions. Monte Carlo uncertainty analyses of decontamination by natural aerosol processes are reported for 1,000, 2,000, 3,000, and 4,000 MW(th) pressurized water reactors and for 1,500, 2,500, and 3,500 MW(th) boiling water reactors. Uncertainty distributions for the decontamination factors and decontamination coefficients as functions of time were developed in the Monte Carlo analyses by considering uncertainties in aerosol processes, material properties, reactor geometry and severe accident progression. Phenomenological uncertainties examined in this work included uncertainties in aerosol coagulation by gravitational collision, Brownian diffusion, turbulent diffusion and turbulent inertia. Uncertainties in aerosol deposition by gravitational settling, thermophoresis, diffusiophoresis, and turbulent diffusion were examined. Electrostatic charging of aerosol particles in severe accidents is discussed. Such charging could affect both the coagulation and deposition of aerosol particles. Electrostatic effects are not considered in most available models of aerosol behavior during severe accidents and cause uncertainties in predicted natural decontamination processes that could not be taken in to account in this work. Median (50%), 90 and 10% values of the uncertainty distributions for effective decontamination coefficients were correlated with time and reactor thermal power. These correlations constitute a simplified model that can be used to estimate the decontamination by natural aerosol processes at 3 levels of conservatism. Applications of the model are described

Accident source terms for Light-Water Nuclear Power Plants. Final report

In 1962 tile US Atomic Energy Commission published TID-14844, ``Calculation of Distance Factors for Power and Test Reactors`` which specified a release of fission products from the core to the reactor containment for a postulated accident involving ``substantial meltdown of the core``. This ``source term``, tile basis for tile NRC`s Regulatory Guides 1.3 and 1.4, has been used to determine compliance with tile NRC`s reactor site criteria, 10 CFR Part 100, and to evaluate other important plant performance requirements. During the past 30 years substantial additional information on fission product releases has been developed based on significant severe accident research. This document utilizes this research by providing more realistic estimates of the ``source term`` release into containment, in terms of timing, nuclide types, quantities and chemical form, given a severe core-melt accident. This revised ``source term`` is to be applied to the design of future light water reactors (LWRs). Current LWR licensees may voluntarily propose applications based upon it

Use of social networks as a CSR communication tool

The aim of this paper is to analyse the use of online social networks as a tool for Corporate Social Responsibility (CSR) communication and management. To this end, an analysis was performed of the messages posted by the 20 Spanish companies with the highest market capitalisation and the responses that they received on two of the most popular online social networks, Facebook and Twitter. The results of the analysis of these data show that the tendency has been to use social networks for the one-way communication of aspects of CSR related with the organisation. Therefore, it is necessary to change the way companies communicate their CSR issues by shifting to a two-way communication approach, as has been the case in other kinds of enterprise relations with their stakeholders.The authors received no direct funding for this research

Niche of harmful alga Aureococcus anophagefferens revealed through ecogenomics

Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of National Academy of Sciences for personal use, not for redistribution. The definitive version was published in Proceedings of the National Academy of Sciences 108 (2011): 4352-4357, doi:10.1073/pnas.1016106108.Harmful algal blooms (HABs) cause significant economic and ecological damage worldwide. Despite considerable efforts, a comprehensive understanding of the factors that promote these blooms has been lacking because the biochemical pathways that facilitate their dominance relative to other phytoplankton within specific environments have not been identified. Here, biogeochemical measurements demonstrated that the harmful 43 Aureococcus anophagefferens outcompeted co-occurring phytoplankton in estuaries with elevated levels of dissolved organic matter and turbidity and low levels of dissolved inorganic nitrogen. We subsequently sequenced the first HAB genome (A. anophagefferens) and compared its gene complement to those of six competing phytoplankton species identified via metaproteomics. Using an ecogenomic approach, we specifically focused on the gene sets that may facilitate dominance within the environmental conditions present during blooms. A. anophagefferens possesses a larger genome (56 mbp) and more genes involved in light harvesting, organic carbon and nitrogen utilization, and encoding selenium- and metal-requiring enzymes than competing phytoplankton. Genes for the synthesis of microbial deterrents likely permit the proliferation of this species with reduced mortality losses during blooms. Collectively, these findings suggest that anthropogenic activities resulting in elevated levels of turbidity, organic matter, and metals have opened a niche within coastal ecosystems that ideally suits the unique genetic capacity of A. anophagefferens and thus has facilitated the proliferation of this and potentially other HABs.Joint Genome Institute is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Efforts were also supported by awards from New York Sea Grant to Stony Brook University, National Oceanic and Atmospheric Administration Center for Sponsored Coastal Ocean Research award #NA09NOS4780206 to Woods Hole Oceanographic Institution, NIH grant GM061603 to Harvard University, and NSF award IOS-0841918 to The University of Tennessee

A Nation-Wide multicenter 10-year (1999-2008) retrospective clinical epidemiological study of female breast cancer in china

<p>Abstract</p> <p>Background</p> <p>According to the very limited cancer registry, incidence and mortality rates for female breast cancer in China are regarded to be increasing especially in the metropolitan areas. Representative data on the breast cancer profile of Chinese women and its time trend over years are relatively rare. The aims of the current study are to illustrate the breast cancer profile of Chinese women in time span and to explore the current treatment approaches to female breast cancer.</p> <p>Methods</p> <p>This was a hospital-based nation-wide and multi-center retrospective study of female primary breast cancer cases. China was divided into 7 regions according to the geographic distribution; from each region, one tertiary hospital was selected. With the exception of January and February, one month was randomly selected to represent each year from year 1999 to 2008 at every hospital. All inpatient cases within the selected month were reviewed and related information was collected based on the designed case report form (CRF). The Cancer Hospital/Institute, Chinese Academy of Medical Sciences (CICAMS) was the leading hospital in this study.</p> <p>Results</p> <p>Four-thousand two-hundred and eleven cases were randomly selected from the total pool of 45,200 patients and were included in the analysis. The mean age at diagnosis was 48.7 years (s.d. = 10.5 yrs) and breast cancer peaked in age group 40-49 yrs (38.6%). The most common subtype was infiltrating ductal carcinoma (86.5%). Clinical stage I & II accounted for 60.6% of 4,211 patients. Three-thousand five-hundred and thirty-four cases had estrogen receptor (ER) and progestin receptor (PR) tests, among them, 47.9% were positive for both. Two-thousand eight-hundred and forty-nine cases had human epidermal growth factor receptor 2(HER-2) tests, 25.8% of them were HER-2 positive. Among all treatment options, surgery (96.9% (4,078/4,211)) was predominant, followed by chemotherapy (81.4% (3,428/4,211). Much less patients underwent radiotherapy (22.6% (952/4,211)) and endocrine therapy (38.0% (1,599/4,211)).</p> <p>Conclusions</p> <p>The younger age of breast cancer onset among Chinese women and more advanced tumor stages pose a great challenge. Adjuvant therapy, especially radiotherapy and endocrine therapy are of great unmet needs.</p