2,143 research outputs found

    Customizing Conception: A Survey of Preimplantation Genetic Diagnosis and the Resulting Social, Ethical, and Legal Dilemmas

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    One in six American couples experience difficulties conceiving a child. With fertility rates at an all time low, the business of treating infertility is booming. However, due to the United States prohibition on government funding for embryonic research, the $4 billion industry of assisted reproductive technologies (ART) has been incompletely monitored and largely removed from oversight. Additionally, due to the fervent abortion debate, in vitro fertilization (IVF) was introduced in the United States without a research phase and procedures have been forced to evolve in the private sector. Thus, the checks and balances on medical innovation that are generally imposed by the federal government for consumer protection are lacking. Decisions about when to go from the laboratory to the clinic are often left solely to the discretion of private physicians. Preimplantation genetic diagnosis (PGD) is just one of many such treatments offered by these clinics. This iBrief examines how, why, and to whom the reproductive procedure of PGD is offered. In addition, it evaluates the prospective effects to society that arise when PGD is used for sex selection and for nontherapeutic or enhancement purposes. Finally, it explores whether and how to regulate PGD in the United States by investigating approaches to policy making that have been adopted by the United Kingdom

    Strategies to Mitigate Supply Chain Disruptions in Miniconvenience Stores

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    Implementing strategies and polices and maintain standards are essential to improving supply chain systems. The purpose of this multiple case study was to explore strategies miniconvenience store managers used to mitigate supply chain disruptions to sustain productivity and increase profits. The population was 4 managers of miniconvenience stores within gas stations located in the southeastern region of the United States who successfully maintained productivity during a supply chain disruption. The conceptual framework for this study was resource dependency theory. Data were collected using company documents, face-to-face interviews and semistructured, open-ended questions. Two themes were identified from the data analysis: building relationships and effective communication. The findings from this study could contribute to positive social change by providing miniconvenience store managers with strategies to increase supply chain capabilities while reducing the impact disruptions have on business performance, customer satisfaction, and profitability. Store managers who minimize supply chain disruptions might improve organizational operative purchasing, decrease prices, increase customer gratification, and improve the standard of living for customers in the communities served

    Retrieval of Ocean Surface Windspeed and Rainrate from the Hurricane Imaging Radiometer (HIRAD) Brightness Temperature Observations

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    The Hurricane Imaging Radiometer (HIRAD) is a new airborne synthetic aperture passive microwave radiometer capable of wide swath imaging of the ocean surface wind speed under heavy precipitation e.g. in tropical cyclones. It uses interferometric signal processing to produce upwelling brightness temperature (Tb) images at its four operating frequencies 4, 5, 6 and 6.6 GHz [1,2]. HIRAD participated in NASA s Genesis and Rapid Intensification Processes (GRIP) mission during 2010 as its first science field campaign. It produced Tb images with ~70 km swath width and 3 km resolution from a ~ 20 km altitude. From this, ocean surface wind speed and column averaged atmospheric liquid water content can be retrieved across the swath. The column averaged liquid water then could be related to an average rain rate. The retrieval algorithm (and the HIRAD instrument itself) is a direct descendant of the nadir-only Stepped Frequency Microwave Radiometer that is used operationally by the NOAA Hurricane Research Division to monitor tropical cyclones [3,4]. However, due to HIRAD s slant viewing geometry (compared to nadir viewing SFMR) a major modification is required in the algorithm. Results based on the modified algorithm from the GRIP campaign will be presented in the paper

    Assimilation of GPM Retrieved Surface Meteorology Variables with ICE-POP Case Studies

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    Built upon Tropical Rainfall Measuring Mission (TRMM) legacy for next-generation global observation of rain and snow. The GPM has a broad global coverage ~70S 70N with a swath of 245/125-km for the Ka (35.5 GHz)/Ku (13.6 GHz) band radar, and 850-km for the 13-channel GMI. GPM also features better retrievals for heavy, moderate, and light rain and snowfall

    LunaNet: a Flexible and Extensible Lunar Exploration Communications and Navigation Infrastructure

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    NASA has set the ambitious goal of establishing a sustainable human presence on the Moon. Diverse commercial and international partners are engaged in this effort to catalyze scientific discovery, lunar resource utilization and economic development on both the Earth and at the Moon. Lunar development will serve as a critical proving ground for deeper exploration into the solar system. Space communications and navigation infrastructure will play an integral part in realizing this goal. This paper provides a high-level description of an extensible and scalable lunar communications and navigation architecture, known as LunaNet. LunaNet is a services network to enable lunar operations. Three LunaNet service types are defined: networking services, position, navigation and timing services, and science utilization services. The LunaNet architecture encompasses a wide variety of topology implementations, including surface and orbiting provider nodes. In this paper several systems engineering considerations within the service architecture are highlighted. Additionally, several alternative LunaNet instantiations are presented. Extensibility of the LunaNet architecture to the solar system internet is discussed

    Striking the right balance in right whale conservation

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    Author Posting. © The Authors, 2009. This article is posted here by permission of NRC Research Press for personal use, not for redistribution. The definitive version was published in Canadian Journal of Fisheries and Aquatic Sciences 66 (2009): 1399-1403, doi:10.1139/F09-115.Despite many years of study and protection, the North Atlantic right whale (Eubalaena glacialis) remains on the brink of extinction. There is a crucial gap in our understanding of their habitat use in the migratory corridor along the eastern seaboard of the United States. Here, we characterize habitat suitability in migrating right whales in relation to depth, distance to shore, and the recently enacted ship speed regulations near major ports. We find that the range of suitable habitat exceeds previous estimates and that, as compared with the enacted 20 nautical mile buffer, the originally proposed 30 nautical mile buffer would protect more habitat for this critically endangered species.This work was supported in part by SERDP/DoD grant W912HQ-04-C-0011 to A.J. Read and P.N. Halpin as well as a James B. Duke Fellowship and a Harvey L. Smith Dissertation Year Fellowship to R.S. Schick

    Promoter-distal RNA polymerase II binding discriminates active from inactive CCAAT/ enhancer-binding protein beta binding sites

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    Transcription factors (TFs) bind to thousands of DNA sequences in mammalian genomes, but most of these binding events appear to have no direct effect on gene expression. It is unclear why only a subset of TF bound sites are actively involved in transcriptional regulation. Moreover, the key genomic features that accurately discriminate between active and inactive TF binding events remain ambiguous. Recent studies have identified promoter-distal RNA polymerase II (RNAP2) binding at enhancer elements, suggesting that these interactions may serve as a marker for active regulatory sequences. Despite these correlative analyses, a thorough functional validation of these genomic co-occupancies is still lacking. To characterize the gene regulatory activity of DNA sequences underlying promoter-distal TF binding events that co-occur with RNAP2 and TF sites devoid of RNAP2 occupancy using a functional reporter assay, we performed cis-regulatory element sequencing (CRE-seq). We tested more than 1000 promoter-distal CCAAT/enhancer-binding protein beta (CEBPB)-bound sites in HepG2 and K562 cells, and found that CEBPB-bound sites co-occurring with RNAP2 were more likely to exhibit enhancer activity. CEBPB-bound sites further maintained substantial cell-type specificity, indicating that local DNA sequence can accurately convey cell-type–specific regulatory information. By comparing our CRE-seq results to a comprehensive set of genome annotations, we identified a variety of genomic features that are strong predictors of regulatory element activity and cell-type–specific activity. Collectively, our functional assay results indicate that RNAP2 occupancy can be used as a key genomic marker that can distinguish active from inactive TF bound sites

    Health service needs and perspectives of remote forest communities in Papua New Guinea: study protocol for combined clinical and rapid anthropological assessments with parallel treatment of urgent cases

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    Introduction Our project follows community requests for health service incorporation into conservation collaborations in the rainforests of Papua New Guinea (PNG). This protocol is for health needs assessments, our first step in coplanning medical provision in communities with no existing health data. Methods and analysis The study includes clinical assessments and rapid anthropological assessment procedures (RAP) exploring the health needs and perspectives of partner communities in two areas, conducted over 6 weeks fieldwork. First, in Wanang village (population c.200), which is set in lowland rainforest. Second, in six communities (population c.3000) along an altitudinal transect up the highest mountain in PNG, Mount Wilhelm. Individual primary care assessments incorporate physical examinations and questioning (providing qualitative and quantitative data) while RAP includes focus groups, interviews and field observations (providing qualitative data). Given absence of in-community primary care, treatments are offered alongside research activity but will not form part of the study. Data are collected by a research fellow, primary care clinician and two PNG research technicians. After quantitative and qualitative analyses, we will report: ethnoclassifications of disease, causes, symptoms and perceived appropriate treatment; community rankings of disease importance and service needs; attitudes regarding health service provision; disease burdens and associations with altitudinal-related variables and cultural practices. To aid wider use study tools are in online supplemental file, and paper and ODK versions are available free from the corresponding author. Ethics and dissemination Challenges include supporting informed consent in communities with low literacy and diverse cultures, moral duties to provide treatment alongside research in medically underserved areas while minimising risks of therapeutic misconception and inappropriate inducement, and PNG research capacity building. Brighton and Sussex Medical School (UK), PNG Institute of Medical Research and PNG Medical Research Advisory Committee have approved the study. Dissemination will be via journals, village meetings and plain language summaries

    The Green Bank North Celestial Cap Pulsar Survey. III. 45 New Pulsar Timing Solutions

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    We provide timing solutions for 45 radio pulsars discovered by the Robert C. Byrd Green Bank Telescope. These pulsars were found in the Green Bank North Celestial Cap pulsar survey, an all-GBT-sky survey being carried out at a frequency of 350 MHz. We include pulsar timing data from the Green Bank Telescope and Low Frequency Array. Our sample includes five fully recycled millisecond pulsars (MSPs, three of which are in a binary system), a new relativistic double neutron star system, an intermediate-mass binary pulsar, a mode-changing pulsar, a 138 ms pulsar with a very low magnetic field, and several nulling pulsars. We have measured two post-Keplerian parameters and thus the masses of both objects in the double neutron star system. We also report a tentative companion mass measurement via Shapiro delay in a binary MSP. Two of the MSPs can be timed with high precision and have been included in pulsar timing arrays being used to search for low-frequency gravitational waves, while a third MSP is a member of the black widow class of binaries. Proper motion is measurable in five pulsars, and we provide an estimate of their space velocity. We report on an optical counterpart to a new black widow system and provide constraints on the optical counterparts to other binary MSPs. We also present a preliminary analysis of nulling pulsars in our sample. These results demonstrate the scientific return of long timing campaigns on pulsars of all types
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