33 research outputs found
INFLUENCE OF SURFACE ROUGHNESS OF COPPER SUBSTRATE ON WETTING BEHAVIOR OF MOLTEN SOLDER ALLOYS
The objective of this study is to understand the effect of surface roughness of the Cu substrate on the wetting of molten solder alloys. Eutectic Sn-Pb, pure Sn and eutectic Sn-Cu solder alloys and Cu substrates with different surface finish viz., highly polished surface, polished surface and unpolished surface were used in this work. Highly polished surface was prepared in Metallography lab, University of Kentucky while other two substrates were obtained from a vendor. Surface roughness properties of each substrate were measured using an optical profilometer. Highly polished surface was found to be of least surface roughness, while unpolished surface was the roughest. Hot-stage microscopy experiments were conducted to promote the wetting behavior of each solder on different Cu substrates. Still digital images extracted from the movies of spreading recorded during hot-stage experiments were analyzed and data was used to generate the plots of relative area of spread of solder versus time. The study of plots showed that surface roughness of the Cu substrate had major influence on spreading characteristics of eutectic Sn-Pb solder alloy. Solder showed better spreading on the Cu substrate with least surface roughness than the substrates with more roughness. No significant influence of surface roughness was observed on the wetting behavior of lead free solders (pure Sn and eutectic Sn-Cu)
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ANDROID MOBILE APPLICATION FOR HOSPITAL EXECUTIVES
Hospitals are the largest and most complex organizations where health care is provided. Safe and effective patient care services in hospitals depend on the efficient decisions made by hospital executives. The main task of hospital executives is to ensure the hospital can provide high quality patient care and services. “Android Mobile Application For Hospital Executives” is an Android application used for displaying hospital performance metrics on a daily basis. This application allows hospital executives to review and monitor hospital operational data with ease of access and in a portable manner. Thus, reducing the effort of the hospital executives to perform their tasks
The role of AP-1 transcription factor expression in androgen sensitive and androgen independent prostate cancer
Development of androgen independent prostate cancer (AIPC) carries a poor prognosis. The underlying molecular mechanisms are complex and not completely understood. Androgen receptor dependent and independent mechanisms have been postulated. AP-1 is a transcription factor whose components are nuclear proteins encoded by c-Jun and c-Fos proto-oncogenes. The possible role of c-Jun and c-Fos in contributing to the development of androgen independent prostate cancer in-vivo using paired human prostate cancer tissue samples has not been studied before. Study hypothesis- AP-1 transcription factor related proteins are dysregulated in the emergence of androgen independent prostate cancer. Aims of the study- 1. To establish a paired clinical cohort of patients in which prostate cancer tissue is available at diagnosis of prostate cancer and also following the development of androgen independence in order to test the hypothesis by immunohistochemistry. 2. To evaluate the expression of AP-1 related proteins in androgen sensitive and androgen independent prostate cancer, by immunohistochemistry. We demonstrated that both androgen sensitive and androgen independent prostate cancers express c-Jun, c-Fos, phosphorylated c-Jun, PKC, COX-2 and AR proteins. A significant proportion of tumours expressed high levels of AP-1 at relapse (c-Jun 68.6%, 35/51; P-Jun, 47%, 24/51; c-Fos 40%, 20/51). An increase or no change in AP-1 (c-Jun, P-Jun & c-Fos) was observed in >80% of AlPCs. Also an increase or no change in PKC (55%), COX-2(70%) and AR (90%) protein expression in AlPC was observed. Differences in the levels of protein expression were observed as androgen sensitive prostate tumours progressed to androgen independent state. In androgen sensitive prostate tumours, we demonstrated a statistically significant correlation in expression of c-Jun, c-Fos and p-Jun proteins (table 14). In androgen independent prostate tumours c-Jun expression correlated with phosphorylated c-Jun with statistical significance (p=<0.0001). We also demonstrated that, high levels of phosphorylated c-Jun and an increase in Protein Kinase C expression at relapse were associated with a decrease in the duration of survival from relapse (p=0.003). Protein Kinase C expression correlated with COX-2 expression in both androgen sensitive as well as in androgen independent prostate tumours (p=0.014 & 0.002 respectively). Also AR protein expression correlated with phosphorylated c-Jun expression in both ASPC and AlPC (p=0.003 & 0.07 respectively). This confirms that both the proteins are involved in the progression of ASPC to AlPC as demonstrated in cell line studies [110, 204]. The study has demonstrated that AP-1 related proteins are dysregulated with the emergence of androgen independent prostate cancer in a subset of patients thus proving the hypothesis
Infliximab induction regimens in steroid refractory acute severe colitis: a multi-centre retrospective cohort study with propensity score analysis
Background:Accelerated induction regimens of infliximab have been proposed to improve response rates in patients with steroid refractory acute severe colitis. Aims:We aimed to determine differences in outcome for acute severe ulcerative colitis between accelerated and standard-dose infliximab.Methods:We collected data on hospitalised patients receiving differing regimens of rescue therapy for steroid refractory Acute Severe Ulcerative Colitis. Our primary outcome was 30-day colectomy rate. Secondary outcomes were colectomy within index admission, 90 days and 12 months. We used propensity score analysis with optimal calliper matching using a priori defined high-risk covariates to reduce potential provider selection bias.Results:We included 131 patients receiving infliximab rescue therapy; 102 patients received standard induction and 29 received accelerated induction. In the unmatched cohort, there was no difference by type of induction in 30-day colectomy rates (18% vs. 20%, p=0.45), colectomy during index admission (13% vs. 20%, p = 0.26) or overall colectomy (20% vs. 24%, p= 0.38). In the propensity score-matched cohort of 52 patients, 30-day colectomy (57% vs. 27%, p = 0.048) and index admission colectomy (53% vs. 23%,p =0.045) rates were higher in those receiving standard induction compared to accelerated induction but there was no difference in overall colectomy rates between the 2 groups (57% vs. 31%, p =0.09). There was no significant difference in length of stay or in complication and infection rates.Conclusion:In a propensity score matched cohort, steroid refractory Acute Severe Ulcerative Colitis patients, short-term, but not long-term, colectomy rates appear to be lower in those receiving accelerated induction regimen
The “Is mpMRI Enough” or IMRIE Study: A Multicentre Evaluation of Prebiopsy Multiparametric Magnetic Resonance Imaging Compared with Biopsy
Background:
Multiparametric magnetic resonance imaging (mpMRI) is now recommended prebiopsy in numerous healthcare regions based on the findings of high-quality studies from expert centres. Concern remains about reproducibility of mpMRI to rule out clinically significant prostate cancer (csPCa) in real-world settings.
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Objective:
To assess the diagnostic performance of mpMRI for csPCa in a real-world setting.
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Design, setting, and participants:
A multicentre, retrospective cohort study, including men referred with raised prostate-specific antigen (PSA) or an abnormal digital rectal examination who had undergone mpMRI followed by transrectal or transperineal biopsy, was conducted. Patients could be biopsy naïve or have had previous negative biopsies.
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Outcome measurements and statistical analysis:
The primary definition for csPCa was International Society of Urological Pathology (ISUP) grade group (GG) ≥2 (any Gleason ≥7); the accuracy for other definitions was also evaluated.
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Results and limitations:
Across ten sites, 2642 men were included (January 2011–November 2018). Mean age and PSA were 65.3 yr (standard deviation [SD] 7.8 yr) and 7.5 ng/ml (SD 3.3 ng/ml), respectively. Of the patients, 35.9% had “negative MRI” (scores 1–2); 51.9% underwent transrectal biopsy and 48.1% had transperineal biopsy, with 43.4% diagnosed with csPCa overall. The sensitivity and negative predictive value (NPV) for ISUP GG ≥ 2 were 87.3% and 87.5%, respectively. The NPVs were 87.4% and 88.1% for men undergoing transrectal and transperineal biopsy, respectively. Specificity and positive predictive value of MRI were 49.8% and 49.2%, respectively. The sensitivity and NPV increased to 96.6% and 90.6%, respectively, when a PSA density threshold of 0.15 ng/ml/ml was used in MRI scores 1–2; these metrics increased to 97.5% and 91.2%, respectively, for PSA density 0.12 ng/ml/ml. ISUP GG ≥ 3 (Gleason ≥4 + 3) was found in 2.4% (15/617) of men with MRI scores 1–2. They key limitations of this study are the heterogeneity and retrospective nature of the data.
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Conclusions:
Multiparametric MRI when used in real-world settings is able to rule out csPCa accurately, suggesting that about one-third of men might avoid an immediate biopsy. Men should be counselled about the risk of missing some significant cancers.
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Patient summary:
Multiparametric magnetic resonance imaging (MRI) is a useful tool for ruling out prostate cancer, especially when combined with prostate-specific antigen density (PSAD). Previous results published from specialist centres can be reproduced at smaller institutions. However, patients and their clinicians must be aware that an early diagnosis of clinically significant prostate cancer could be missed in nearly 10% of patients by relying on MRI and PSAD alone