534 research outputs found
Cyclic thermomechanical testing of 316 stainless steel
Materials used for components such as power plant steam pipes, gas turbines discs and die forming machinery can be subject to combinations of extreme loading and temperature conditions. In addition, the materials can contain or develop cracks. Once a crack has initiated, the conditions under which the components operate can cause these cracks to propagate. This paper is concerned with the experimental testing of 316 stainless steel, corner cracked samples under thermomechanical fatigue conditions, and the measurement of the crack propagation during testing using alternating current potential difference readings. Fracture mechanics (Paris Law) methods have been used in the processing of the experimental data
What is the test's accuracy in my practice population? Tailored meta-analysis provides a plausible estimate
Estimating a testâs accuracy using tailored meta-analysis â How setting-specific data may aid study selection
Medical Help-Seeking for Sexual Concerns in Prostate Cancer Survivors.
INTRODUCTION: Although sexual dysfunction is common after prostate cancer, men's decisions to seek help for sexual concerns are not well understood. AIM: Describe predictors of actual prior help-seeking and intended future medical help-seeking for sexual dysfunction in prostate cancer survivors. METHODS: A cross-sectional survey of 510 prostate cancer survivors assessed masculine beliefs, attitudes, support/approval from partner/peer networks (subjective norm), and perceived control as predictors of medical help-seeking for sexual concerns. A theory of planned behavior (TPB) perspective was used to examine actual prior and planned future behavior and contributing factors. Statistical analyses included multiple and logistic regressions. MAIN OUTCOME MEASURES: Intention to see a doctor for sexual advice or help in the next 6 months was measured using the intention subscale adapted from the Attitudes to Seeking Help after Cancer Scale. Prior help-seeking was measured with a dichotomous yes/no scale created for the study. RESULTS: Men were Mage 71.69 years (SD = 7.71); 7.54 years (SD = 4.68) post-diagnosis; received treatment(s) (58.1% radical prostatectomy; 47.1% radiation therapy; 29.4% hormonal ablation); 81.4% reported severe ED (IIED 0-6) and 18.6% moderate-mild ED (IIED 7-24). Overall, 30% had sought sexual help in the past 6 months, and 24% intended to seek help in the following 6 months. Prior help-seeking was less frequent among men with severe ED. Sexual help-seeking intentions were associated with lower education, prior sexual help-seeking, sexual importance/ priority, emotional self-reliance, positive attitude, and subjective norm (R(2) = 0.56). CONCLUSION: The TPB has utility as a theoretical framework to understand prostate cancer survivors' sexual help-seeking decisions and may inform development of more effective interventions. Masculine beliefs were highly salient. Men who were more emotionally self-reliant and attributed greater importance to sex formed stronger help-seeking intentions. Subjective norm contributed most strongly to help-seeking intentions suggesting that health professionals/partners/peers have a key role as support mechanisms and components of psycho-sexual interventions
Results of a prepilot study of potential test material for the external quality assessment of reticulocyte haemoglobin content
Generation of <em>Escherichia coli</em> nitroreductase mutants conferring improved cell sensitization to the prodrug CB1954
Escherichia coli nitroreductase (NTR) activates the prodrug CB1954 to a cytotoxic derivative, allowing selective sensitization of NTR-expressing cells or tumors to the prodrug. This is one of several enzyme-prodrug combinations that are under development for cancer gene therapy, and the system has now entered clinical trials. Enhancing the catalytic efficiency of NTR for CB1954 could improve its therapeutic potential. From the crystal structure of an enzyme-ligand complex, we identified nine amino acid residues within the active site that could directly influence prodrug binding and catalysis. Mutant libraries were generated for each of these residues and clones screened for their ability to sensitize E. coli to CB1954. Amino acid substitutions at six positions conferred markedly greater sensitivity to CB1954 than did the WT enzyme; the best mutants, at residue F124, resulted in âŒ5-fold improvement. Using an adenovirus vector, we introduced the F124K NTR mutant into human SK-OV-3 ovarian carcinoma cells and showed it to be âŒ5-fold more potent in sensitizing the cells to CB1954 at the clinically relevant prodrug concentration of 1 ÎŒM than was the WT enzyme. Enhanced mutant NTRs such as F124K should improve the efficacy of the NTR/CB1954 combination in cancer gene therapy
Multi-tissue transcriptome analysis identifies key sexual development-related genes of the ornate spiny lobster (Panulirus ornatus)
Sexual development involves the successive and overlapping processes of sex determination, sexual differentiation, and ultimately sexual maturation, enabling animals to reproduce. This provides a mechanism for enriched genetic variation which enables populations to withstand ever-changing environments, selecting for adapted individuals and driving speciation. The molecular mechanisms of sexual development display a bewildering diversity, even in closely related taxa. Many sex determination mechanisms across animals include the key family of âdoublesex- and male abnormal3-related transcription factorsâ (Dmrts). In a few exceptional species, a single Dmrt residing on a sex chromosome acts as the master sex regulator. In this study, we provide compelling evidence for this model of sex determination in the ornate spiny lobster Panulius ornatus, concurrent with recent reports in the eastern spiny lobster Sagmariasus verreauxi. Using a multi-tissue transcriptomic database established for P. ornatus, we screened for the key factors associated with sexual development (by homology search and using previous knowledge of these factors from related species), providing an in-depth understanding of sexual development in decapods. Further research has the potential to close significant gaps in our understanding of reproductive development in this ecologically and commercially significant order
Accuracy and Precision Analysis for a Biophotonic Assay of C-Reactive Protein
This is the author accepted manuscript. The final version is available from the Royal Society of Chemistry via the DOI in this recordA multiplexed biophotonic assay platform has been developed using the localised particle
plasmon in gold nanoparticles assembled in an array and functionalised for two assays: total
IgG and C-reactive protein (CRP). A protein A/G (PAG) assay, calibrated with a NIST
reference material, shows a maximum surface coverage of max = 7.13 ± 0.19 mRIU,
equivalent to 1.5 ng mm-2 of F(ab)-presenting antibody. The CRP capture antibody has an
equivalent surface binding density of max = 2.95 ± 0.41 mRIU indicating a 41% capture
antibody availability. Free PAG binding to the functionalised anti-CRP surface shows that
only 47 ± 3 % of CRP capture antibodies are correctly presenting Fab regions for antigen
capture. The accuracy and precision of the CRP sensor assay was assessed with 54 blood
samples containing spiked CRP in the range 2 â 160 mg/L. The mean accuracy was 0.42 mg/L
with Confidence Interval (CI) at 95% from -14.7 to 13.8 mg/L and the precision had a
Coefficient of Variation (CV) of 10.6% with 95% CI 0.9% - 20.2%. These biophotonic platform
performance metrics indicate a CRP assay with 2 - 160 mg/L dynamic range, performed in 8
minutes from 5 L of whole blood without sample preparation.Attomarker Ltd
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