3,956 research outputs found
Ecdysteroid Titers in Mated and Unmated \u3ci\u3eDrosophila melanogaster\u3c/i\u3e Females
Radioimmunoassay was used to determine ecdysteroid titers in mated or unmated Drosophila melanogaster females. Whole-body ecdysteroid titers increase after mating and this response is more pronounced after 12–24 hours than it is immediately after mating. In one experiment, females were mated to transgenic males deficient in accessory gland proteins to test whether these peptides mediate the observed increase in female whole-body ecdysteroid titers. Females mated to such transgenic males do not show a pronounced increase in whole-body ecdysteroid titers. The effect of mating on female hemolymph ecdysteroid titers was also investigated. Hemolymph ecdysteroid titers decrease after mating. The ecdysteroid titer change in the hemolymph may result from yolk protein uptake of ecdysteroids into developing vitellogenic oocytes as a consequence of male accessory gland protein stimulation of female oocyte maturation and yolk protein synthesis following mating
Whose Side are Ethics Codes On? Power, Responsibility and the Social Good
The moral authority of ethics codes stems from an assumption that they serve
a unified society, yet this ignores the political aspects of any shared
resource. The sociologist Howard S. Becker challenged researchers to clarify
their power and responsibility in the classic essay: Whose Side Are We On.
Building on Becker's hierarchy of credibility, we report on a critical
discourse analysis of data ethics codes and emerging conceptualizations of
beneficence, or the "social good", of data technology. The analysis revealed
that ethics codes from corporations and professional associations conflated
consumers with society and were largely silent on agency. Interviews with
community organizers about social change in the digital era supplement the
analysis, surfacing the limits of technical solutions to concerns of
marginalized communities. Given evidence that highlights the gulf between the
documents and lived experiences, we argue that ethics codes that elevate
consumers may simultaneously subordinate the needs of vulnerable populations.
Understanding contested digital resources is central to the emerging field of
public interest technology. We introduce the concept of digital differential
vulnerability to explain disproportionate exposures to harm within data
technology and suggest recommendations for future ethics codes.Comment: Conference on Fairness, Accountability, and Transparency (FAT* '20),
January 27-30, 2020, Barcelona, Spain. Correcte
Episodic rainfall influences the distribution and abundance of the regular sea urchin Lytechinus variegatus in Saint Andrew Bay, northern Gulf of Mexico
The distribution and abundance of Lytechinus variegatus (Lamarck) were determined at three shallow-water stations in Saint Andrew Bay, FL, in the northern Gulf of Mexico. Populations were monitored at 4-mo intervals from Aug. 1997 to Aug. 1999 along 2- X 10-m transects, with four transects at each station. In Aug. 1997 individuals ranged in size from 15- to 63-mm diameter (mean = 38 mm; density= 1.4 individuals (ind.) m-2) at Station 1 (Stations 2 and 3 were not sampled on that date). By Oct. 1997 individuals at Station 1 ranged in size from 26 to 62 mm (mean = 48 mm; density = 0.6 ind. m-2), suggesting the growth of individuals within the population. At Station 2, individuals ranged between 50 and 70 mm (mean = 59 mm; densities = 1.0 ind. m-2) and at Station 3 between 30 and 79 mm (mean= 51 mm; densities = 1.4 ind, m-2) in Oct. 1997, indicating a population with no recent recruits. A mass mortality event was observed in April 1998 and was attributed to reduced salinities resulting from above-average rainfall in the previous month. Sea urchins were absent at Stations 1 and 2, whereas at Station 3 postdisturbance recruits were smaller (mean = 28 mm) and densities lower. Sea urchin tests were also observed at beach stations proximate to Stations 1 and 2. By July 1998 the populations had partially recovered at Stations 2 and 3 (densities = 0.6 and 1.1 ind. m-2, respectively), but test diameters were small at both stations. Test diameters had increased in Dec. 1998 at Station 3 when compared with those of July, but individuals at Station 2 showed overall smaller test diameters (mean = 28 mm), and densities had decreased again, presumably after another mass mortality caused by another major rainfall in Sep. In April 1999 test diameters had decreased further at Stations 2 and 3, indicating emigration or death of larger animals. We suggest that the shallow-water Saint Andrew Bay population of L. variegatus is reduced for several years at a time by episodic heavy rainfalls. This observation emphasizes the importance of density-independent processes controlling the distribution and abundance of marine organisms
Consumer Bankruptcy Panel Strip Off in Chapter 7: The Limits of Dewsnup
Consumer Bankruptcy Panel Strip Off in Chapter 7: The Limits of Dewsnu
Episodic Rainfall Influences the Distribution and Abundance of the Regular Sea Urchin Lytechinus variegatus in Saint Andrew Bay, Northern Gulf of Mexico
The distribution and abundance of Lytechinus variegatus (Lamarck) were determined at three shallow-water stations in Saint Andrew Bay, FL, in the northern Gulf of Mexico. Populations were monitored at 4-mo intervals from Aug. 1997 to Aug. 1999 along 2- X 10-m transects, with four transects at each station. In Aug. 1997 individuals ranged in size from 15- to 63-mm diameter (mean = 38 mm; density= 1.4 individuals (ind.) m-2) at Station 1 (Stations 2 and 3 were not sampled on that date). By Oct. 1997 individuals at Station 1 ranged in size from 26 to 62 mm (mean = 48 mm; density = 0.6 ind. m-2), suggesting the growth of individuals within the population. At Station 2, individuals ranged between 50 and 70 mm (mean = 59 mm; densities = 1.0 ind. m-2) and at Station 3 between 30 and 79 mm (mean= 51 mm; densities = 1.4 ind, m-2) in Oct. 1997, indicating a population with no recent recruits. A mass mortality event was observed in April 1998 and was attributed to reduced salinities resulting from above-average rainfall in the previous month. Sea urchins were absent at Stations 1 and 2, whereas at Station 3 postdisturbance recruits were smaller (mean = 28 mm) and densities lower. Sea urchin tests were also observed at beach stations proximate to Stations 1 and 2. By July 1998 the populations had partially recovered at Stations 2 and 3 (densities = 0.6 and 1.1 ind. m-2, respectively), but test diameters were small at both stations. Test diameters had increased in Dec. 1998 at Station 3 when compared with those of July, but individuals at Station 2 showed overall smaller test diameters (mean = 28 mm), and densities had decreased again, presumably after another mass mortality caused by another major rainfall in Sep. In April 1999 test diameters had decreased further at Stations 2 and 3, indicating emigration or death of larger animals. We suggest that the shallow-water Saint Andrew Bay population of L. variegatus is reduced for several years at a time by episodic heavy rainfalls. This observation emphasizes the importance of density-independent processes controlling the distribution and abundance of marine organisms
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Antimicrobial Resistance in Neisseria gonorrhoeae: Proceedings of the STAR Sexually Transmitted Infection-Clinical Trial Group Programmatic Meeting.
The goal of the Sexually Transmitted Infection Clinical Trial Group's Antimicrobial Resistance (AMR) in Neisseria gonorrhoeae (NG) meeting was to assemble experts from academia, government, nonprofit and industry to discuss the current state of research, gaps and challenges in research and technology and priorities and new directions to address the continued emergence of multidrug-resistant NG infections. Topics discussed at the meeting, which will be the focus of this article, include AMR NG global surveillance initiatives, the use of whole genome sequencing and bioinformatics to understand mutations associated with AMR, mechanisms of AMR, and novel antibiotics, vaccines and other methods to treat AMR NG. Key points highlighted during the meeting include: (i) US and International surveillance programs to understand AMR in NG; (ii) the US National Strategy for combating antimicrobial-resistant bacteria; (iii) surveillance needs, challenges, and novel technologies; (iv) plasmid-mediated and chromosomally mediated mechanisms of AMR in NG; (v) novel therapeutic (eg, sialic acid analogs, factor H [FH]/Fc fusion molecule, monoclonal antibodies, topoisomerase inhibitors, fluoroketolides, LpxC inhibitors) and preventative (eg, peptide mimic) strategies to combat infection. The way forward will require renewed political will, new funding initiatives, and collaborations across academic and commercial research and public health programs
The effects of alcohol on plasma lipid mediators of inflammation resolution in patients with Type 2 diabetes mellitus
Background
Type 2 diabetes mellitus is characterized by peripheral insulin resistance and low-grade systemic inflammation. Inflammation resolution is recognised as an important process driven by specialised pro-resolving mediators of inflammation (SPMs) and has the potential to moderate chronic inflammation. Alcohol has the potential to affect synthesis of SPMs by altering key enzymes involved in SPM synthesis and may influence ongoing inflammation associated with Type 2 diabetes mellitus.
Aims
(i) To examine the effects of alcohol consumed as red wine on plasma SPM in men and women with Type 2 diabetes in a randomised controlled trial and (ii) compare baseline plasma SPM levels in the same patients with those of healthy volunteers.
Methods
Twenty-four patients with Type 2 diabetes mellitus were randomized to a three-period crossover study with men drinking red wine 300 ml/day (∼31 g alcohol/day) and women drinking red wine 230 ml/day (∼24 g alcohol/day), or equivalent volumes of dealcoholized red wine (DRW) or water, each for 4 weeks. The SPM 18-hydroxyeicosapentaenoic acid (18-HEPE), E-series resolvins (Rv) (RvE1-RvE3), 17-hydroxydocosahexaenoic acid (17-HDHA), and D-series resolvins (RvD1, 17R-RvD1, RvD2, RvD5), 14-hydroxydocosahexaenoic acid (14-HDHA) and Maresin 1 were measured at the end of each period. A baseline comparison of plasma SPM, hs CRP, lipids and glucose was made with healthy volunteers.
Results
Red wine did not differentially affect any of the SPM measured when compared with DRW or water. Baseline levels of the hs-CRP and the SPM 18-HEPE, 17-HDHA, RvD1 and 17R-RvD1 in patients with Type 2 diabetes mellitus were all significantly elevated compared with healthy controls and remained so after adjusting for age and gender.
Conclusion
Moderate alcohol consumption as red wine does not alter plasma SPM in patients with Type 2 diabetes mellitus. The elevation of SPM levels compared with healthy volunteers may be a homeostatic response to counter ongoing inflammation
Does Access to Health Care Impact Survival Time after Diagnosis of AIDS?
Lack of access to health care is often blamed for poor health outcomes, but this effect is not supported by existing HIV/AIDS literature. The authors examined the association between access to care and survival time after progression to AIDS, using survival analysis methods. This study combined data from two CDC sponsored studies of HIV-infected persons, a cross-sectional interview study and a longitudinal medical record review study. Study subjects included 752 persons who progressed to AIDS before December 31, 1999, and were patients at either of two major HIV care facilities in Detroit, MIchigan. Separate statistical models were used to test associations between survival time after meeting the criteria for AIDS and two indicators of access to health care: (1) perceived access to health care and (2) health care utilization patterns. Perceived access was not associated with survival time after AIDS, but patterns of health care utilization were significantly associated with survival time after AIDS (HR = 2.04, p < 0.001). Individuals who received a greater proportion of their care in the ER had a worse survival prognosis than those who received more of their health care in an outpatient clinic setting. It is crucial that we provide HIV-infected populations with tools that enable them to access a regular source of health care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63272/1/10872910252972276.pd
Evaluating Prostate Cancer Using Fractional Tissue Composition of Radical Prostatectomy Specimens and Pre-Operative Diffusional Kurtosis Magnetic Resonance Imaging.
BACKGROUND: Evaluating tissue heterogeneity using non-invasive imaging could potentially improve prostate cancer assessment and treatment. METHODS: 20 patients with intermediate/high-risk prostate cancer underwent diffusion kurtosis imaging, including calculation of apparent diffusion (Dapp) and kurtosis (Kapp), prior to radical prostatectomy. Whole-mount tissue composition was quantified into: cellularity, luminal space, and fibromuscular stroma. Peripheral zone tumors were subdivided according to Gleason score. RESULTS: Peripheral zone tumors had increased cellularity (p<0.0001), decreased fibromuscular stroma (p<0.05) and decreased luminal space (p<0.0001). Gleason score ≥4+3 tumors had significantly increased cellularity and decreased fibromuscular stroma compared to Gleason score ≤3+4 (p<0.05). In tumors, there was a significant positive correlation between median Kapp and cellularity (ρ = 0.50; p<0.05), and a negative correlation with fibromuscular stroma (ρ = -0.45; p<0.05). In normal tissue, median Dapp had a significant positive correlation with luminal space (ρ = 0.65; p<0.05) and a negative correlation with cellularity (ρ = -0.49; p<0.05). Median Kapp and Dapp varied significantly between tumor and normal tissue (p<0.0001), but only median Kapp was significantly different between Gleason score ≥4+3 and ≤3+4 (p<0.05). CONCLUSIONS: Peripheral zone tumors have increased cellular heterogeneity which is reflected in mean Kapp, while normal prostate has a more homogeneous luminal space and cellularity better represented by Dapp.Research support from National Institute of Health Research-Cambridge Biomedical Research Centre, Cancer Research UK (C19212/A911376, C19212/A16628), Hutchinson Whampoa Limited, Addenbrooke’s Charitable Trust, and the Cancer Research UK/Engineering and Physical Sciences Research Council Imaging Centre in Cambridge and Manchester. MRI acquisition for this study funded by the Cambridge Experimental Cancer Medicine Centre and the Royal College of Surgeons of England.This is the final version of the article. It first appeared from the Public Library of Science via http://dx.doi.org/10.1371/journal.pone.015965
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