249 research outputs found

    Risk based approach for procedures' optimization

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    Despite an increase in the process automation, different activities remain mainly operator driven, as the loading and unloading of tankers, maintenance operations, and so on. In these cases, the activities performed by the operator can be critical, both for the safety and for the product quality. Optimizing the operational procedures is thus a key factor for quality and safety. A risk assessment of the procedure can be adopted as a base for optimisation, highlighting which of the tasks within the procedure mainly contributes to the risk of the working activity. Usually the analysis of the procedures is carried on through a task analysis as in Builes et al. (2014). In this paper the task analysis is used as a starting point for a quantitative risk assessment carried on through an integrated dynamic decision analysis. The logical-probabilistic model of the procedure is elaborated jointly with a consequences analysis, obtaining a risk assessment for all the sequences of tasks of the work procedure under analysis. The risk assessment considered both possible equipment failures and the potential operational errors in executing the tasks. The proposed approach is in this paper demonstrated through the application of the integrated decision analysis for the operation of unloading of ammonia in a plant for the production and storage of fertilizers

    Accelerating Rural Growth Through Collective Action: Groups\u27 Activities and Determinants of Participation in Southwestern Nigeria

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    This study was conducted to investigate the types of activities promoted by cooperative groups and the determinants of participation intensity of members in cooperative activities in southwestern Nigeria. A multistage sampling approach was used to select 326 cooperators (45 groups). Data collected were analyzed using descriptive statistics, difference of means test, and Tobit regression.Cooperative groups engaged in farm and off-farm activities such as arable crop production, fish farming, agricultural products processing, and produce marketing, among others. Farm input procurements and access to market information (74 percent), cooperative credits and thrift (53 percent), social networking (37 percent), multipurpose commercial activities (21.6 percent), and political influence (17 percent) were given as reasons for interest and participation in groups\u27 activities. Income realized by cooperators was significantly and consistently higher than income of non-cooperators who engaged in the same economic activity. Participation intensity was influenced by gender, farm size cultivated, and the social status of members

    Oligomeric States and Hydrodynamic Properties of Lysyl Oxidase-Like 2

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    Lysyl oxidase-like 2 (LOXL2) has emerged as a promising therapeutic target against metastatic/invasive tumors and organ and tissue fibrosis. LOXL2 catalyzes the oxidative deamination of lysine and hydroxylysine residues in extracellular matrix (ECM) proteins to promote crosslinking of these proteins, and thereby plays a major role in ECM remodeling. LOXL2 secretes as 100-kDa full-length protein (fl-LOXL2) and then undergoes proteolytic cleavage of the first two scavenger receptor cysteine-rich (SRCR) domains to yield 60-kDa protein (Δ1-2SRCR-LOXL2). This processing does not affect the amine oxidase activity of LOXL2 in vitro. However, the physiological importance of this cleavage still remains elusive. In this study, we focused on characterization of biophysical properties of fl- and Δ1-2SRCR-LOXL2s (e.g., oligomeric states, molecular weights, and hydrodynamic radii in solution) to gain insight into the structural role of the first two SRCR domains. Our study reveals that fl-LOXL2 exists predominantly as monomer but also dimer to the lesser extent when its concentration is <~1 mM. The hydrodynamic radius (Rh) determined by multi-angle light scattering coupled with size exclusion chromatography (SEC-MALS) indicates that fl-LOXL2 is a moderately asymmetric protein. In contrast, Δ1-2SRCR-LOXL2 exists solely as monomer and its Rh is in good agreement with the predicted value. The Rh values calculated from a 3D modeled structure of fl-LOXL2 and the crystal structure of the precursor Δ1-2SRCR-LOXL2 are within a reasonable margin of error of the values determined by SEC-MALS for fl- and Δ1-2SRCR-LOXL2s in mature forms in this study. Based on superimposition of the 3D model and the crystal structure of Δ1-2SRCR-LOXL2 (PDB:5ZE3), we propose a configuration of fl-LOXL2 that explains the difference observed in Rh between fl- and Δ1-2SRCR-LOXL2s in solution

    Epigenetic Alteration of the Cancer-Related Gene TGFBI in B Cells Infected with Epstein–Barr Virus and Exposed to Aflatoxin B1: Potential Role in Burkitt Lymphoma Development

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    Burkitt lymphoma (BL) is a malignant B cell neoplasm that accounts for almost half of pediatric cancers in sub-Saharan African countries. Although the BL endemic prevalence is attributable to the combination of Epstein–Barr virus (EBV) infection with malaria and environmental carcinogens exposure, such as the food contaminant aflatoxin B1 (AFB1), the molecular determinants underlying the pathogenesis are not fully understood. Consistent with the role of epigenetic mechanisms at the interface between the genome and environment, AFB1 and EBV impact the methylome of respectively leukocytes and B cells specifically. Here, we conducted a thorough investigation of common epigenomic changes following EBV or AFB1 exposure in B cells. Genome-wide DNA methylation profiling identified an EBV–AFB1 common signature within the TGFBI locus, which encodes for a putative tumor suppressor often altered in cancer. Subsequent mechanistic analyses confirmed a DNA-methylation-dependent transcriptional silencing of TGFBI involving the recruitment of DNMT1 methyltransferase that is associated with an activation of the NF-ÎșB pathway. Our results reveal a potential common mechanism of B cell transformation shared by the main risk factors of endemic BL (EBV and AFB1), suggesting a key determinant of disease that could allow the development of more efficient targeted therapeutic strategies

    Challenges in the Diagnosis and Management of Acquired Nontraumatic Urethral Strictures in Boys in Yaoundé, Cameroon

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    Introduction. Urethral strictures in boys denote narrowing of the urethra which can be congenital or acquired. In case of acquired strictures, the etiology is iatrogenic or traumatic and rarely infectious or inflammatory. The aim of this study was to highlight the diagnostic and therapeutic difficulties of acquired nontraumatic urethral strictures in boys in YaoundĂ©, Cameroon. Methodology. The authors report five cases of nontraumatic urethral strictures managed at the Pediatric Surgery Department of the YGOPH over a two-year period (November 2012–November 2014). In order to confirm the diagnosis of urethral stricture, all patients were assessed with both cystourethrography and urethrocystoscopy. Results. In all the cases the urethra was inflammatory with either a single or multiple strictures. The surgical management included internal urethrotomy (n=1), urethral dilatation (n=1), vesicostomy (n=2), and urethral catheterization (n=3). With a median follow-up of 8.2 months (4–16 months) all patients remained symptoms-free. Conclusion. The authors report the difficulties encountered in the diagnosis and management of nontraumatic urethral strictures in boys at a tertiary hospital in YaoundĂ©, Cameroon. The existence of an inflammatory etiology of urethral strictures in boys deserves to be considered

    Meals in western eating and drinking

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    Meals are a way of organizing eating into events that have a particular structure and form, and they play an indisputable and even self-evident role within the rhythms and routines of everyday life. In late modern societies, concern about the fate of meals has arisen in both public and academic discourse. It has been suggested that eating is characterized today by individualization, destructuration, and informalization and that communal meals are increasingly being replaced by snacks and solitary eating. This chapter focuses on meals in today’s affluent societies and reflects on why meals are considered important, how meals are defined, and what material elements and social dimensions they contain. It looks at how societal and cultural changes and ecological concerns may influence the organization and future of meals, and it suggests that the content of meals will change in response to the need to diminish the ecological burden of food production and consumption. In particular, plant-based options will at least partly need to replace meat and other animal-based foods. However, there is no reason to expect that the meal as a social institution will break down. Despite the fact that not all meals are characterized by conviviality and companionship, they continue to serve as a significant arena of human sociability and togetherness. Sharing food is, after all, an essential part of being human.Non peer reviewe
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