16 research outputs found
Genetic Algorithm Optimization Model for Determining the Probability of Failure on Demand of the Safety Instrumented System
A more accurate determination for the Probability of Failure on Demand (PFD) of the Safety Instrumented System (SIS) contributes to more SIS realiability, thereby ensuring more safety and lower cost. IEC 61508 and ISA TR.84.02 provide the PFD detemination formulas. However, these formulas suffer from an uncertaity issue due to the inclusion of uncertainty sources, which, including high redundant systems architectures, cannot be assessed, have perfect proof test assumption, and are neglegted in partial stroke testing (PST) of impact on the system PFD. On the other hand, determining the values of PFD variables to achieve the target risk reduction involves daunting efforts and consumes time. This paper proposes a new approach for system PFD determination and PFD variables optimization that contributes to reduce the uncertainty problem. A higher redundant system can be assessed by generalizing the PFD formula into KooN architecture without neglecting the diagnostic coverage factor (DC) and common cause failures (CCF). In order to simulate the proof test effectiveness, the Proof Test Coverage (PTC) factor has been incorporated into the formula. Additionally, the system PFD value has been improved by incorporating PST for the final control element into the formula. The new developed formula is modelled using the Genetic Algorithm (GA) artificial technique. The GA model saves time and effort to examine system PFD and estimate near optimal values for PFD variables. The proposed model has been applicated on SIS design for crude oil test separator using MATLAB. The comparison between the proposed model and PFD formulas provided by IEC 61508 and ISA TR.84.02 showed that the proposed GA model can assess any system structure and simulate industrial reality. Furthermore, the cost and associated implementation testing activities are reduced
Planning and implementing COVID-19 mass vaccination clinics
Purpose: The COVID-19 pandemic is an unprecedented global public health crisis. Mass vaccination with safe and effective vaccines to achieve herd immunity requires a whole-of-society approach. Primary care has played a key role in those countries that have succeeded in rapidly vaccinating a large proportion of their populations, particularly those most at risk. In this special report we synthesize existing guidelines and peer-reviewed studies to provide family physicians with practical guidance on planning and implementing COVID-19 mass immunization clinics.
Methods: PubMed, Ovid, MEDLINE, Epub Ahead of Print, Embase and Google Scholar were used to search for relevant literature using keywords, including âCOVID-19â, âmass vaccinationâ, âcampaignâ, âstandardâ and âbest practiceâ. We also identified and analyzed national and international guidelines.
Results: Forty-six relevant articles, reports and guidelines were identified and synthesized. Key considerations for COVID-19 mass vaccination clinics include establishing a leadership structure and key roles, identifying optional locations, clinic layout and workflow, day-to-day operations including infection prevention and control, and communication strategies. Ongoing data collection is required to evaluate and continuously improve mass vaccination efforts. Primary care can play a key role in organizing clinics and ensuring populations who have been made vulnerable by social and economic policies are being reached.
Conclusions: Planning and implementing a successful COVID-19 mass vaccination campaign requires a number of key steps and considerations. As the COVID-19 vaccine rollout occurs in various countries, research will be required to identify key factors for success in different healthcare systems to inform future pandemic responses.http://deepblue.lib.umich.edu/bitstream/2027.42/167674/1/AFM-393-21_PP.pdfDescription of AFM-393-21_PP.pdf : Main ArticleSEL
Vitamin D Receptor Gene (Fok-I) Polymorphisms in Type 1 Diabetic Children; Case Study in Zagazig University Hospitals
Background: Many meta-analyses studied the association between vitamin D receptor (VDR) gene polymorphism and type 1 diabetes (T1DM) susceptibility.
Objective: This study was designed to assess the role of VDR gene (FOK-I) polymorphisms in type 1 diabetic children from Zagazig University Hospitals in Egypt.
Patients and Method: In this case-control study, the genotypes of VDR gene (FOK-I) polymorphisms were assessed in 180 type 1 diabetic children and 120 healthy matched age controls by PCR-RFLP analysis.
Results: A high statistical difference between patient and control regarding VDR gene (FOK-I) polymorphisms, where 44% of the patient group had heterozygous genotype (AG) compared to 8.3% in the control group. AG genotype has almost a higher risk nine times odds ratio (OR) = 8.8 than AA genotype in diabetic patients. There was a significant increase in the G allele in the patient group. Moreover, a significant association between (FOK-I) polymorphisms and T1DM complications was also observed.
Conclusion: (AG) genotype of VDR gene (FOK-I) polymorphisms could be a risk factor for T1DM complications. So, VDR gene (FOK-I) polymorphisms should be performed with other genetic studies for early prediction, detection and prevention of microvascular complications of T1DM that adversely affect health-related quality of life of Egyptian children and burden the primary care units
Characterization of greater middle eastern genetic variation for enhanced disease gene discovery
The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia1-3, has resulted in an elevated burden of recessive disease4. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized âgenetic purgingâ. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics
Characterization of Kallikrein-related Peptidase-8 in Normal Human Epidermis and Psoriasis
Kallikrein-8 (KLK8) is a relatively-uncharacterized epidermal protease. Although proposed to regulate wound-healing and barrier repair in KLK8-deficient mouse skin, KLK8-catalytic activity was never demonstrated in human epidermis and its regulators and targets remain largely unknown. KLK8 overexpression was reported in inflammatory skin diseases, but the underlying mechanisms are poorly understood. In this thesis, we elucidated for the first time KLK8-specific activity in normal human non-palmoplantar stratum corneum and sweat, and identified epidermal regulators and targets that augment its involvement in a skin-barrier proteolytic cascade. Given that inflammatory skin diseases have interlinked immune and epidermal roots, we hypothesized that epidermal KLK8 expression is distinctly regulated by the aberrant T-cell immunity implicated in the two common skin diseases, psoriasis and atopic dermatitis, independent of skin-barrier insults. We profiled secretion of KLK8 by normal human keratinocytes post-treatment with T-helper (Th1, Th17 and Th2) cell-derived cytokines, and investigated the effect of KLK8 overexpression on terminal keratinocyte differentiation and innate immunity gene expression. Our results show that TNFα and IL-17A synergistically induce potent KLK8 hyper-secretion, while IL4 and IL13 reduce its expression. TNFα and IL-17A overexpression and KLK8 hyperactivity resulted in hyperkeratosis and upregulation of keratinocyte innate defense genesâ expression mimicking psoriatic lesions. Consistently, KLK8 expression was reduced in lesional skin of atopic dermatitis patients and significantly elevated in lesional skin and sera of psoriatic patients. KLK8 levels correlated with psoriasis skin severity and were significantly reduced by effective treatment with biologic TNFα-blockers, correlating positively with psoriasis clearance. Thus, KLK8 is a new epidermal psoriasis therapeutic target. We performed high throughput screens of small molecule compound libraries to identify KLK8-specific inhibitors and discovered promising KLK8 small molecule inhibitors with IC50s in the nanomolar range. This thesis provides original findings corroborating KLK8 as an active serine protease in normal human skin and a down-stream epidermal respondent to TNFα and IL17A overexpression in psoriatic skin. Our novel KLK8-specific inhibitors may have future potential as topical barrier-enhancing agents in psoriasis.Ph
Erratum: Unleashing the therapeutic potential of human kallikrein-related serine proteases
Production and Application of Advanced High Nitrogen Steel
Nitrogen was considered for long period to be in the same category as certain undesirable residual elements in steel, which are generally harmful for its properties. This was believed as high nitrogen contained steel is subject to ageing with deterioration of its plasticity with time.
Recently, it was noticed that nitrogen has significant effect on mechanical properties, phase stability, corrosion behavior and oxidation resistance. Therefore, the technologies have developed to produce nitrogen and high nitrogen steels. The technologies for production of
nitrogen steel including arc furnace , induction furnace, electro slag remelting, pressurised induction furnace, pressurised electroslag remelting, powder metallurgy and mechanical alloying - in addition to- the surface technologies such as gaseous solution nitriding, plasma
furnaces, laser technology.Nitrogen became promising alloying element in steel, where nitrogen alloyed different steel grades such as Mn âsteel, HSLA steel, duplex stainless steel, austenitic, ferritic and martensitic stainless steels which have applications in different fields. Steel Technology Department in Central Metallurgical R & D Institute (CMRDI) has significant contribution in development nitrogen steels using different techniques
A decision tree model for accurate prediction of sand erosion in elbow geometry
Erosion of piping components, e.g., elbows, is a hazardous phenomenon that frequently occurs due to sand flow with fluids during petroleum production. Early prediction of the sand's erosion rate (ER) is essential for ensuring a safe flow process and material integrity. Some models have been applied to determine the ER of the sand in the literature. However, these models have been created based on specific data to require a model for application to wide-range data. Moreover, the previous models have not studied relationships between independent and dependent variables. Thus, this research aims to use machine learning techniques, namely linear regression and decision tree (DT), to predict the ER robustly. The optimum model, the DT model, was evaluated using various trend analysis and statistical error analyses (SEA) techniques, namely the correlation coefficient (R). The evaluation results proved proper physical behavior for all independent variables, along with high accuracy and the DT model robustness. The proposed DT method can accurately predict the ER with R of 0.9975, 0.9911, 0.9761, and 0.9908, AAPRE of 5.0%, 6.27%, 6.26%, and 5.5%, RMSE of 2.492E-05, 6.189E-05, 9.310E-05, and 5.339E-05, and STD of 13.44, 6.66, 8.01, and 11.44 for the training, validation, testing, and whole datasets, respectively. Hence, this study delivers an effective, robust, accurate, and fast prediction tool for ER determination, significantly saving the petroleum industry's cost and time
Proteinase-activated receptors (PARs): Differential signalling by kallikrein-related peptidases KLK8 and KLK14
We compared signalling pathways such as calcium transients, MAPK activation, ÎČ-arrestin interactions and receptor internalization triggered by kallikrein-related peptidases (KLKs) 8 and 14 in human and rat proteinase-activated receptor (PAR)2-expressing human embryonic kidney (HEK) and Kirsten transformed rat kidney (KNRK) cells. Further, we analy sed processing by KLK8 vs. KLK14 of synthetic human and rat PAR2-derived sequences representing the cleavageactivation domain of PAR2. Our data show that like KLK14, KLK8 can unmask a PAR2 receptor-activating sequence from a peptide precursor. However, whilst KLK8, like KLK14, can signal in rat-PAR2-expressing KNRK cells, this enzyme cannot signal via human PAR2 in HEK or KNRK cells, but rather, disarms HEK PAR1. Thus, KLK8 and KLK14 can signal differentially via the PARs to affect tissue function. © 2012 by Walter de Gruyter · Berlin · Boston