217 research outputs found
Does egg production represent adult female copepod growth? A call to account for body weight changes
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Existing Data Format for Two-Parameter Beta-Gamma Histograms for Radioxenon
There is a need to establish a commonly acceptable format for storing beta-gated coincidence data for stations in the International Monitoring System (IMS) for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The current aerosol RMS type data format is not applicable for radioxenon in that the current format contains implicit assumptions specific to conventional gamma-ray spectrometry. Some assumptions in the current RMS format are not acceptable for the beta-gated spectra expected from the U.S. Department of Energy PNNL Automated Radioxenon Sampler-Analyzer (ARSA) and other similar systems under use or development from various countries. The RMS data format is not generally applicable for radioxenon measurements in the CTBT for one or more of the following main reasons: 1) The RMS format does not currently support 2-dimensional data. That is, the RMS data format is setup for a simple l-dimensional gamma-ray energy histogram. Current data available from the ARSA system and planned for other radioxenon monitors includes spectral information from gamma-rays and betas/conversion electrons. It is worth noting that the beta/conversion electron energy information will be used to separate the contributions from the different radioxenons. 2) The RMS data format assumes that the conversion between counts and activity can be calculated based (in part) on a simple calibration curve (detector efficiency curve) that depends only on energy of the gamma-ray. In the case of beta-gated gamma-ray spectra and for 2-dimensional spectra, there are generally two detector calibration curves that must be convoluted, the lower energy cutoff for the betas must be considered, and the energy acceptance window must be taken into account to convert counts into activity. . 3) The RMS format has header information that contains aerosol-specific information that allows the activity (Bq) calculated to be converted into a concentration (Bq/SCM). This calculation is performed by dividing the activity calculated (Bq) into number of standard cubic meters of air (SCM) passed through the filters. Most xenon-samplers do not have a 100% collection and transfer efficiency, and these efficiencies should not be assumed constant, so that the total volume flow through the sampler may not be used to convert activity into concentration. There is a pretty straightforward analogy that requires, instead, the total volume of xenon gas measured by the xenon station for the conversion. The following paper describes one possible file format for storing the multi-parameter beta-gamma coincidence spectra generated by the DOE PNNL ARSA sampler. This format proposal was generated as a draft guide to begin discussions
The impact of radiotherapy in the treatment of desmoid tumours. An international survey of 110 patients. A study of the Rare Cancer Network
PURPOSE: A multi-centre study to assess the value of combined surgical resection and radiotherapy for the treatment of desmoid tumours. PATIENTS AND METHODS: One hundred and ten patients from several European countries qualified for this study. Pathology slides of all patients were reviewed by an independent pathologist. Sixty-eight patients received post-operative radiotherapy and 42 surgery only. Median follow-up was 6 years (1 to 44). The progression-free survival time (PFS) and prognostic factors were analysed. RESULTS: The combined treatment with radiotherapy showed a significantly longer progression-free survival than surgical resection alone (p smaller than 0.001). Extremities could be preserved in all patients treated with combined surgery and radiotherapy for tumours located in the limb, whereas amputation was necessary for 23% of patients treated with surgery alone. A comparison of PFS for tumour locations proved the abdominal wall to be a positive prognostic factor and a localization in the extremities to be a negative prognostic factor. Additional irradiation, a fraction size larger than or equal to 2 Gy and a total dose larger than 50 Gy to the tumour were found to be positive prognostic factors with a significantly lower risk for a recurrence in the univariate analysis. This analysis revealed radiotherapy at recurrence as a significantly worse prognostic factor compared with adjuvant radiotherapy. The addition of radiotherapy to the treatment concept was a positive prognostic factor in the multivariate analysis. CONCLUSION: Postoperative radiotherapy significantly improved the PFS compared to surgery alone. Therefore it should always be considered after a non-radical tumour resection and should be given preferably in an adjuvant setting. It is effective in limb preservation and for preserving the function of joints in situations where surgery alone would result in deficits, which is especially important in young patients
Validation of pharmacodynamic assays to evaluate the clinical efficacy of an antisense compound (AEG 35156) targeted to the X-linked inhibitor of apoptosis protein XIAP
The inhibitor of apoptosis protein, XIAP, is frequently overexpressed in chemoresistant human tumours. An antisense oligonucleotide (AEG 35156/GEM 640) that targets XIAP has recently entered phase I trials in the UK. Method validation data are presented on three pharmacodynamic assays that will be utilised during this trial. Quantitative RT-PCR was based on a Taqman assay and was confirmed to be specific for XIAP. Assay linearity extended over four orders of magnitude. MDA-MB-231/U6-E1 cells and clone X-G4 stably expressing an RNAi vector against XIAP were chosen as high and low XIAP expression quality controls (QCs). Within-day and between-day coefficients of variation (CVs) in precision for cycle threshold (CT) and delta CT values (employing GAPDH and beta 2 microglobulin as housekeepers) were always less than 10%. A Western blotting technique was validated using a GST–XIAP fusion protein as a standard and HeLa cells and SF268 (human glioblastoma) cells as high and low XIAP expression QCs. Specificity of the final choice of antibody for XIAP was evaluated by analysing a panel of cell lines including clone X-G4. The assay was linear over a 29-fold range of protein concentration and between-day precision was 29% for the low QC and 23% for the high QC when normalised to GAPDH. XIAP protein was also shown to be stable at −80°C for at least 60 days. M30-Apoptosense™ plasma Elisa detects a caspase-cleaved fragment of cytokeratin 18 (CK18), believed to be a surrogate marker for tumour cell apoptosis. Generation of an independent QC was achieved through the treatment of X-G4 cells with staurosporine and collection of media. Measurements on assay precision and kit-to-kit QC were always less than 10%. The M30 antigen (CK18-Asp396) was stable for 3 months at −80°C, while at 37°C it had a half-life of 80–100 h in healthy volunteer plasma. Results from the phase I trial are eagerly awaited
A database of marine phytoplankton abundance, biomass and species composition in Australian waters
There have been many individual phytoplankton datasets collected across Australia since the mid 1900s, but most are unavailable to the research community. We have searched archives, contacted researchers, and scanned the primary and grey literature to collate 3,621,847 records of marine phytoplankton species from Australian waters from 1844 to the present. Many of these are small datasets collected for local questions, but combined they provide over 170 years of data on phytoplankton communities in Australian waters. Units and taxonomy have been standardised, obviously erroneous data removed, and all metadata included. We have lodged this dataset with the Australian Ocean Data Network (http://portal.aodn.org.au/) allowing public access. The Australian Phytoplankton Database will be invaluable for global change studies, as it allows analysis of ecological indicators of climate change and eutrophication (e.g., changes in distribution; diatom:dinoflagellate ratios). In addition, the standardised conversion of abundance records to biomass provides modellers with quantifiable data to initialise and validate ecosystem models of lower marine trophic levels
Health care access dimensions and cervical cancer screening in South Africa: analysis of the world health survey.
Background
Cervical cancer is the most commonly diagnosed cancer and the leading cause of cancer mortality among women in sub-Saharan Africa. Recent recommendations for cervical cancer primary prevention highlight HPV vaccination, and secondary prevention through screening. However, few studies have examined the different dimensions of health care access, and how these may influence screening behavior, especially in the context of clinical preventive services. Methods
Using the 2003 South Africa World Health Survey, we determined the prevalence of cervical cancer screening with pelvic examinations and/or pap smears among women ages 18 years and older. We also examined the association between multiple dimensions of health care access and screening focusing on the affordability, availability, accessibility, accommodation and acceptability components. Results
About 1 in 4 (25.3%, n = 65) of the women who attended a health care facility in the past year got screened for cervical cancer. Screened women had a significantly higher number of health care providers available compared with unscreened women (mean 125 vs.12, p-value Conclusions
Our findings suggest that cost issues (affordability component) and other patient level factors (captured in the acceptability, accessibility and accommodation components) were less important predictors of screening compared with availability of physicians in this population. Meeting cervical cancer screening and HPV vaccination goals will require significant investments in the health care workforce, improving health care worker density in poor and rural areas, and improved training of the existing workforce
The relative effects of upwelling and river flow on the phytoplankton diversity patterns in the ria of A Coruña (NW Spain)
Phytoplankton species assemblages in estuaries are connected to those in rivers and marine environments by local hydrodynamics leading to a continuous flow of taxa. This study revealed differential effects of upwelling and river flow on phytoplankton communities observed in 2011 along a salinity gradient from a river reservoir connected to the sea through a ria-marine bay system in A Coruña (NW Spain, 43° 16-21’ N, 8° 16-22’ W). With 130 phytoplankton taxa identified, the assemblages were dominated in general by diatoms, particularly abundant in the bay and in the estuary, but also by chlorophycea and cyanobacteria in the reservoir. Considering the entire seasonal cycle, the local assemblages were mainly characterized by changes in cryptophytes and diatoms, small dinoflagellates and some freshwater chlorophycea. Salinity, nitrate, and organic matter variables, were the main environmental factors related to the changes in the phytoplankton communities through the system, while phosphate and nitrite were also important for local communities in the estuary and the bay, respectively. The corresponding local phytoplankton assemblages showed moderate levels of connectivity. The estuarine community shared a variable number of taxa with the adjacent zones, depending on the relative strength of upwelling (major influence from the bay) and river flow (major influence of the reservoir) but had on average 35% of unique taxa. Consequently, local and zonal diversity patterns varied seasonally and were not simply related to the salinity gradient driven by the river flow.ANILE (CTM2009-08396 and CTM2010-08804-E), FIOME (CTM2011-28792-C02-01-MAR), and MEFIO (CTM2011-28792-C02-02-MAR) of the Plan Nacional de I+D+i (Spain), and RADIALES of the Instituto Español de OceanografÃa (IEO, Spain).Versión del editor2,01
Validation of food store environment secondary data source and the role of neighborhood deprivation in Appalachia, Kentucky
Background
Based on the need for better measurement of the retail food environment in rural settings and to examine how deprivation may be unique in rural settings, the aims of this study were: 1) to validate one commercially available data source with direct field observations of food retailers; and 2) to examine the association between modified neighborhood deprivation and the modified retail food environment score (mRFEI).
Methods
Secondary data were obtained from a commercial database, InfoUSA in 2011, on all retail food outlets for each census tract. In 2011, direct observation identifying all listed food retailers was conducted in 14 counties in Kentucky. Sensitivity and positive predictive values (PPV) were compared. Neighborhood deprivation index was derived from American Community Survey data. Multinomial regression was used to examine associations between neighborhood deprivation and the mRFEI score (indicator of retailers selling healthy foods such as low-fat foods and fruits and vegetables relative to retailers selling more energy dense foods).
Results
The sensitivity of the commercial database was high for traditional food retailers (grocery stores, supermarkets, convenience stores), with a range of 0.96-1.00, but lower for non-traditional food retailers; dollar stores (0.20) and Farmer’s Markets (0.50). For traditional food outlets, the PPV for smaller non-chain grocery stores was 38%, and large chain supermarkets was 87%. Compared to those with no stores in their neighborhoods, those with a supercenter [OR 0.50 (95% CI 0.27. 0.97)] or convenience store [OR 0.67 (95% CI 0.51, 0.89)] in their neighborhood have lower odds of living in a low deprivation neighborhood relative to a high deprivation neighborhood.
Conclusion
The secondary commercial database used in this study was insufficient to characterize the rural retail food environment. Our findings suggest that neighborhoods with high neighborhood deprivation are associated with having certain store types that may promote less healthy food options
Recent Surveys in the Forests of Ulu Segama Malua, Sabah, Malaysia, Show That Orang-utans (P. p. morio) Can Be Maintained in Slightly Logged Forests
BACKGROUND: Today the majority of wild great ape populations are found outside of the network of protected areas in both Africa and Asia, therefore determining if these populations are able to survive in forests that are exploited for timber or other extractive uses and how this is managed, is paramount for their conservation. METHODOLOGY/PRINCIPAL FINDINGS: In 2007, the "Kinabatangan Orang-utan Conservation Project" (KOCP) conducted aerial and ground surveys of orang-utan (Pongo pygmaeus morio) nests in the commercial forest reserves of Ulu Segama Malua (USM) in eastern Sabah, Malaysian Borneo. Compared with previous estimates obtained in 2002, our recent data clearly shows that orang-utan populations can be maintained in forests that have been lightly and sustainably logged. However, forests that are heavily logged or subjected to fast, successive coupes that follow conventional extraction methods, exhibit a decline in orang-utan numbers which will eventually result in localized extinction (the rapid extraction of more than 100 m(3) ha(-1) of timber led to the crash of one of the surveyed sub-populations). Nest distribution in the forests of USM indicates that orang-utans leave areas undergoing active disturbance and take momentarily refuge in surrounding forests that are free of human activity, even if these forests are located above 500 m asl. Displaced individuals will then recolonize the old-logged areas after a period of time, depending on availability of food sources in the regenerating areas. CONCLUSION/SIGNIFICANCE: These results indicate that diligent planning prior to timber extraction and the implementation of reduced-impact logging practices can potentially be compatible with great ape conservation
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