System dynamics modeling of generic quality improvement programs

Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 133-134).by Omar S. Khan.S.B.and M.Eng

Effect of water immersion on monomer and strength of FRC

This journal suppl. entitled: Abstracts of the Academy of Dental Materials Annual Meeting, 8-11 October 2014 - Bologna, ItalyPURPOSE: There is an interest in the use of fiber-reinforced composite (FRC) to support the concept of minimal invasive dentistry. The exposure of FRC to the oral environment causes detrimental effect of water sorption (Takashi et al. Dent Mat 2006 22:291). With time water molecules will act as plasticizers and decrease the mechanical properties (Mese and Guzel. J Prosthet Dent 2008 99:153). Monomer system is the backbone of the dental composite (Garcia et al. Clinical Dentistry 2005: 215) and residual monomer may dissolve in water (Tanaka et al. J Oral Rehab 1991 18:353). Some released monomers are knownto elicit cytotoxic effects (Sakaguchi and Powers. Craig’s Restorative Dental Materials 2012:343), and methyl methacrylate (MMA) is mentioned as cytotoxic (Pradeep and Sreekumar. J Contemp Dent Pract 2012 6:838). This study investigated the effect of water immersion duration on monomer release and the compressive strength of fiber-reinforced composite. METHODS AND MATERIALS: Materials used were: E-glass fibre (Stick Tech, Finland), bis-GMA (Sigma–Aldrich, USA), MMA (ProSciTech, Australia), CQ (Esstech, USA) and CEMA (Esstech, USA). Fifteen specimens (2mm×2mm×25mm) with the composition of: 78.4% bis-GMA+19.6%MMA+ 1.0%CQ + 1.0%CEMA were prepared and divided into 2 groups: compressive strength (CS-12specimens) and residual monomer (RM-3specimens). Each specimen had two fiber rovings of 25mm and placed in a mould, and light-cured with halogen light-curing unit on both sides for 3×40 s. Specimens from each group were divided into three groups based on the water immersion durations (1, 14 and 21 days) and immersed into 10 ml distilled water at 37 ◦C. The three RM-specimens were analyzed using HPLC to test the residual monomer concentration. All CS-specimens were tested using UTM (Torsee’s UTM, Tokyo Testing Machine Mfg., Co., Ltd., Japan) for the compressive strength. RESULTS: The data of MMA concentration was descriptively analyzed. It started on day 1 (2352.96µg/ml) followed by an increase on day14 (3567.15µg/ml) and decreased on day 21 (2427.19µg/ml). Compressive strength showed an average (MPa) for day 1 (93.84±8.30); day 14 (67.83±4.82) and day 21 (51.08±2.10), respectively. Data from the compressive strength was analyzed by ANOVA, and it proved a significant decrease as the water immersion duration increases (p < 0.05). CONCLUSION: The duration of water immersion of e-glass FRC showed different effect on the concentration of released monomer and the compressive strength. Highest concentration of MMA concentration occurred on day 14 and followed by a decrease. As for the compressive strength, it decreased as the water immersion duration increased.postprin

Role of leptin and its receptors in the pathogenesis of thyroid cancer

Leptin is a multifunctional adipose-derived cytokines that play a critical role in bodyweight homeostasis and energy balance. Recently, leptin and leptin receptor dysreulation have been reported in variety of malignant cells including thyroid. Leptin modulates growth and proliferation of cancer cells via activation of various growth and survival signaling pathways including JAK/STAT, PI3-kinase/AKT and/or Map kinases. In this review, current understanding of leptin\u27s role in the pathogenesis of thyroid cancer has been described

Trends in hospital-based management of acute asthma from a teaching hospital in South Asia.

The aim of this study is to evaluate the hospital-based management of acute asthma in south Asia and to compare practices over a 10-year period. Adult patients (n = 102) admitted at a teaching hospital with acute asthma were studied. Documentation of precipitating factors, family history and physical signs were inadequate in more than half of patients. Pulse oximetry was documented in 95 (93%) patients, but peak flow monitoring was performed only in 50 (49%) patients. Ten-year trend showed deterioration in history and physical examination skills, under use of peak flow readings, and poor pre-discharge instructions. Some aspects of improved care included frequent use of pulse oximeter, preference of inhaled over systemic bronchodilators and increased use of systemic steroids. Significant deficiencies were identified in hospital-based management of acute asthma. Most aspects of asthma care continued to fall short of asthma guidelines

Bacteriuria and pregnancy outcome: A prospective hospital-based study in Pakistani women

The prevalence of bacteriuria in Pakistani women and its association with complications of pregnancy was studied. Out of 1579 women, 77 had bacteriuria (4.8%). There was no association of age, gravidity, parity, haemoglobin, pre-eclampsia, mode of delivery, gestational age at delivery, preterm delivery and low birth-weight with presence of bacteriuria. With detection and treatment the pregnancy outcome of women with bacteriuria in pregnancy was the same as that of those without

Rapid translation of clinical guidelines into executable knowledge : a case study of COVID-19 and online demonstration

Introduction: We report a pathfinder study of AI/knowledge engineering methods to rapidly formalise COVID‐19 guidelines into an executable model of decision making and care pathways. The knowledge source for the study was material published by BMJ Best Practice in March 2020. Methods: The PROforma guideline modelling language and OpenClinical.net authoring and publishing platform were used to create a data model for care of COVID‐19 patients together with executable models of rules, decisions and plans that interpret patient data and give personalised care advice. Results: PROforma and OpenClinical.net proved to be an effective combination for rapidly creating the COVID‐19 model; the Pathfinder 1 demonstrator is available for assessment at https://www.openclinical.net/index.php?id=746. Conclusions: This is believed to be the first use of AI/knowledge engineering methods for disseminating best‐practice in COVID‐19 care. It demonstrates a novel and promising approach to the rapid translation of clinical guidelines into point of care services, and a foundation for rapid learning systems in many areas of healthcare

Cross-talk between NFkB and the PI3-Kinase/AKT pathway can be targeted in primary effusion lymphoma (PEL) cell lines for efficient apoptosis

Background: A number of constitutively activated signaling pathways play critical roles in the survival and growth of primary effusion lymphoma cells (PELs) including NFkB and PI3/AKT kinase cascades. NFkBis constitutively activated in a number of malignancies, including multiple myeloma, Burkitt’s lymphoma and diffuse large cell B-cell lymphoma. However, its role in primary effusion lymphoma has not been fully explored. Methodology/Principal Findings: We used pharmacological inhibition and gene silencing to define the role of NFkB in growth and survival of PEL cells. Inhibition of NFkB activity by Bay11-7085 resulted in decreased expression of p65 in the nuclear compartment as detected by EMSA assays. In addition, Bay11-7085 treatment caused de-phosphorylation of AKT and its downstream targets suggesting a cross-talk between NFkB and the PI3-kinase/AKT pathway. Importantly, treatment of PEL cells with Bay11-7085 led to inhibition of cell viability and induced apoptosis in a dose dependent manner. Similar apoptotic effects were found when p65 was knocked down using specific small interference RNA. Finally, co-treatment of PEL cells with suboptimal doses of Bay11-7085 and LY294002 led to synergistic apoptotic responses in PEL cells.Conclusion/Significance: These data support a strong biological-link between NFkB and the PI3-kinase/AKT pathway in the modulation of anti-apoptotic effects in PEL cells. Synergistic targeting of these pathways using NFKB- and PI3-kinase/AKT- inhibitors may have a therapeutic potential for the treatment of PEL and possibly other malignancies with constitutive activation of these pathway

Dendrimer-RNA nanoparticles generate protective immunity against lethal Ebola, H1N1 influenza, and

Vaccines have had broad medical impact, but existing vaccine technologies and production methods are limited in their ability to respond rapidly to evolving and emerging pathogens, or sudden outbreaks. Here, we develop a rapid-response, fully synthetic, singledose, adjuvant-free dendrimer nanoparticle vaccine platform wherein antigens are encoded by encapsulated mRNA replicons. To our knowledge, this system is the first capable of generating protective immunity against a broad spectrum of lethal pathogen challenges, including H1N1 influenza, Toxoplasma gondii, and Ebola virus. The vaccine can be formed with multiple antigenexpressing replicons, and is capable of eliciting both CD8⁺ T-cell and antibody responses. The ability to generate viable, contaminant-free vaccines within days, to single or multiple antigens, may have broad utility for a range of diseases

Stability analysis of the magnetized casson nanofluid propagating through an exponentially shrinking/stretching plate: Dual solutions

In this research, we intend to develop a dynamical system for the magnetohydrodynamic (MHD) flow of an electrically conducting Casson nanofluid on exponentially shrinking and stretching surfaces, in the presence of a velocity and concertation slip effect, with convective boundary conditions. There are three main objectives of this article, specifically, to discuss the heat characteristics of flow, to find multiple solutions on both surfaces, and to do stability analyses. The main equations of flow are governed by the Brownian motion, the Prandtl number, and the thermophoresis parameters, the Schmid and Biot numbers. The shooting method and three-stage Lobatto IIIa formula have been employed to solve the equations. The ranges of the dual solutions are fwc1≤fw and λc≤λ , while the no solution ranges are fwc1>fw and λc>λ . The results reveal that the temperature of the fluid increases with the extended values of the thermophoresis parameter, the Brownian motion parameter, and the Hartmann and Biot numbers, for both solutions. The presence of dual solutions depends on the suction parameter. In order to indicate that the first solution is physically relevant and stable, a stability analysis has been performed