scholarly journals A Sensitivity Analysis on the Consequences Assessment in Cases of Toxic Substance Released by Pipelines

2008 ◽  
Vol 4 (1) ◽  
pp. 39-56
Author(s):  
Gagliardi Valentina ◽  
Citro Lucia
Keyword(s):  
Sensitivity Analysis ◽  
Toxic Substance ◽  
Threshold Level ◽  
Critical Threshold ◽  
Toxic Substances ◽  
Threshold Values ◽  
Hazard Area ◽  
The Impact ◽  
Harmful Effects

A Sensitivity Analysis on the Consequences Assessment in Cases of Toxic Substance Released by Pipelines This paper presents preliminary results of a study aimed at evaluating the impact on man and environment of major accident hazards related to transmission pipelines carrying toxic substances. In particular, it describes the assessment of the consequences of potential toxic release from pipelines, expressed in terms of hazard area, that is the zone in which the concentration of a toxic substance exceed a critical threshold level and induce harmful effects on people and the environment. Moreover, a sensitivity analysis has been undertaken, emphasizing the role of threshold values on the results obtained.

Can financial inclusion reduce the presence of corruption? Evidence from selected countries in Africa

2020 ◽  
Vol 47 (11) ◽  
pp. 1345-1362
Author(s):  
Folorunsho M. Ajide
Keyword(s):  
Random Effect ◽  
Secondary Data ◽  
Threshold Level ◽  
Financial Inclusion ◽  
Least Square ◽  
African Countries ◽  
Content Type ◽  
The Impact ◽  
Control Of Corruption

PurposeThe purpose of this paper is to evaluate the impact of financial inclusion (FI) on control of corruption in selected African countries.Design/methodology/approachThe study employs secondary data spanning over a period of 2005–2016. These data are sourced from IMF's International Financial Statistics, World Bank Development Indicators, Global Financial Development Database, Transparency International and International Country Risk Guide. The author uses Sarma (2008) approach to construct the FI index for 13 countries in Africa. The author applies random effect, robust least square and instrumental variable (IV) estimations to examine the impact of FI on control of corruption in Africa.FindingsThe author finds that financial inclusion improves the control of corruption. The author tests for possible FI threshold to avoid the case of extreme FI in Africa. The results show that there is a threshold level if reached, FI would have negative impacts in the control of corruption. This may likely happen mainly due to weak institutions in Africa. The results are robust to alternative proxy for control of corruption and various alternative estimation techniques.Practical implicationsThe finding indicates that FI can serve as part of toolkits for reducing corruption in Africa.Originality/valueThis study stresses the important role of FI in the economic system. It is the first paper that empirically suggests the role of FI in controlling corruption in Africa.

scholarly journals The role of incoherent feedforward circuits in regulating precision of event timing

2020 ◽  
Author(s):  
Supravat Dey ◽  
Sherin Kannoly ◽  
Pavol Bokes ◽  
John J Dennehy ◽  
Abhyudai Singh
Keyword(s):  
Single Cells ◽  
Threshold Level ◽  
Cellular Growth ◽  
Critical Threshold ◽  
E Coli ◽  
Cellular Events ◽  
Event Timing ◽  
Simple Model System ◽  
Cell Data

AbstractTriggering of cellular events often relies on the level of a key gene product crossing a critical threshold. Achieving precision in event timing in spite of noisy gene expression facilitates high-fidelity functioning of diverse processes from biomolecular clocks, apoptosis and cellular differentiation. Here we investigate the role of an incoherent feedforward circuit in regulating the time taken by a bacterial virus (bacteriophage lambda) to lyse an infected Escherichia coli cell. Lysis timing is the result of expression and accumulation of a single lambda protein (holin) in the E. coli cell membrane up to a critical threshold level, which triggers the formation of membrane lesions. This easily visualized process provides a simple model system for characterizing event-timing stochasticity in single cells. Intriguingly, lambda’s lytic pathway synthesizes two functionally opposite proteins: holin and antiholin from the same mRNA in a 2:1 ratio. Antiholin sequesters holin and inhibits the formation of lethal membrane lesions, thus creating an incoherent feedforward circuit. We develop and analyze a stochastic model for this feedforward circuit that considers correlated bursty expression of holin/antiholin, and their concentrations are diluted from cellular growth. Interestingly, our analysis shows the noise in timing is minimized when both proteins are expressed at an optimal ratio, hence revealing an important regulatory role for antiholin. These results are in agreement with single cell data, where removal of antiholin results in enhanced stochasticity in lysis timing.

scholarly journals Intracellular Complexes of Viral Spike and Cellular Receptor Accumulate during Cytopathic Murine Coronavirus Infections

1998 ◽  
Vol 72 (4) ◽  
pp. 3278-3288 ◽  
Author(s):  
Pasupuleti V. Rao ◽  
Thomas M. Gallagher
Keyword(s):  
Trypan Blue ◽  
Hepatitis Virus ◽  
Syncytium Formation ◽  
Threshold Level ◽  
Inducible Promoter ◽  
Critical Threshold ◽  
Murine Hepatitis Virus ◽  
Trypan Blue Exclusion ◽  
Hela Cell Lines

ABSTRACT Murine hepatitis virus (MHV) infections exhibit remarkable variability in cytopathology, ranging from acutely cytolytic to essentially asymptomatic levels. In this report, we assess the role of the MHV receptor (MHVR) in controlling this variable virus-induced cytopathology. We developed human (HeLa) cell lines in which the MHVR was produced in a regulated fashion by placing MHVR cDNA under the control of an inducible promoter. Depending on the extent of induction, MHVR levels ranged from less than ∼1,500 molecules per cell (designated Rlo) to ∼300,000 molecules per cell (designated Rhi). Throughout this range, the otherwise MHV-resistant HeLa cells were rendered susceptible to infection. However, infection in the Rlo cells occurred without any overt evidence of cytopathology, while the corresponding Rhi cells died within 14 h after infection. When the HeLa-MHVR cells were infected with vaccinia virus recombinants encoding MHV spike (S) proteins, the Rhi cells succumbed within 12 h postinfection; Rlo cells infected in parallel were intact, as judged by trypan blue exclusion. This acute cytopathology was not due solely to syncytium formation between the cells producing S and MHVR, because fusion-blocking antiviral antibodies did not prevent it. These findings raised the possibility of an intracellular interaction between S and MHVR in the acute cell death. Indeed, we identified intracellular complexes of S and MHVR via coimmunoprecipitation of endoglycosidase H-sensitive forms of the two proteins. We suggest that MHV infections can become acutely cytopathic once these intracellular complexes rise above a critical threshold level.

Current perspectives on the remediation methods of marine plastic pollution: a review

2020 ◽  
Vol 65 (2) ◽  
pp. 69-86
Author(s):  
Andreea Lup ◽  
Mihai Gorea ◽  
Denisa Bruhs
Keyword(s):  
Marine Environment ◽  
Biological Effects ◽  
Marine Species ◽  
Plastic Pollution ◽  
Different Types ◽  
Waves And Tides ◽  
Bacteria And Fungi ◽  
The Impact ◽  
Harmful Effects

Plastic debris represents a contemporary point of concern for the marine environment, being discharged into the ocean at an alarming scale. However, the quantity of waste that is found in the ocean is unknown. Where does this waste come from, and where does it end up are questions that scientists and researchers are still trying to accurately answer. The majority of plastic products that make their way into the ocean come mainly from human activities. Most of them land on beaches, and eventually find their way into the ocean, being washed away by waves and tides. To assess the impact of these pollutants that are found in the marine environment, it is necessary to determine the concentration of the chemicals accumulating in the biomass, and the effects they cause. There are numerous biological effects which lead to many obvious diseases in marine species. Also, these harmful effects determine changes in community structure, the modification of the habitat and local or complete extinction of many aquatic species. This review aims to lay out the present situation of the marine environment, and the effects of the pollution caused by industrialization and urbanization. Different types of remediation approaches have been discussed, such as physical remediation techniques. Besides that, the role of numerous bacteria and fungi that are capable of breaking down these chemicals that surround us, has been highlighted and point at some of the bioremediation technologies that are currently available.

The impact of perceived discrimination on personality among Chinese migrant children: The moderating role of parental support

2018 ◽  
Vol 64 (3) ◽  
pp. 248-257 ◽  
Author(s):  
Xiaoping Xiang ◽  
Daniel Fu Keung Wong ◽  
Ke Hou
Keyword(s):  
Parental Support ◽  
Perceived Discrimination ◽  
Personality Development ◽  
Migrant Children ◽  
Convenience Sample ◽  
Policy Makers ◽  
The Impact ◽  
Moderating Role ◽  
Harmful Effects

Background: Previous research has indicated that perceived discrimination has harmful effects on migrant children’s physical, mental and behavioral health. However, little is known as to whether these harmful effects cumulate to impact on migrant children’s personalities. Aims: This study examines the effect of perceived discrimination on personality, as well as the moderating role of parental support in the discrimination–personality linkage. Methods: A purposeful convenience sample of 215 migrant children in Beijing, China, completed a standardized questionnaire. Results: Migrant children experienced a moderate level of perceived discrimination, with Form 8 students experiencing greater discrimination than lower grades and those with lower family incomes also experiencing greater discrimination than those with higher family incomes. Perceived discrimination significantly predicted neuroticism; parental support significantly predicted extraversion, openness, agreeableness and conscientiousness, but the moderating effect of parental support was only marginally significant for the relation between discrimination and conscientiousness. Conclusion: This study underlines the need for researchers and policy makers to pay more attention to the impact of perceived discrimination on migrant children’s personality development.

Robustness Testing of Model Based Multiple Criteria Decisions: Fundamentals and Applications

2015 ◽  
Vol 14 (05) ◽  
pp. 1035-1062
Author(s):  
Andrzej P. Wierzbicki ◽  
Marek Makowski ◽  
Janusz Granat
Keyword(s):  
Sensitivity Analysis ◽  
Multiple Criteria ◽  
Decision Situation ◽  
Combined Model ◽  
Robustness Testing ◽  
Scalar Optimization ◽  
Basic Assumptions ◽  
Basic Model ◽  
The Impact

Robustness or insensitivity is a desirable property of decisions; however, most texts on robustness and/or sensitivity analysis do not define it precisely. A broad literature in this field concentrates on robust design of decisions (including robust optimization). This paper focuses on robustness testing, that is, checking whether a design has actually resulted in robust properties of the system if some of basic assumptions are changed. We propose a general framework of such robustness testing and show that robustness is a property of the relation between three (classes of) models: a basic model of the decision situation, a second model of possible perturbations of the first model, and a model of implementation of the decision, optionally taking into account some measurements of the impact of perturbations. Typical approaches to robustness or sensitivity analysis assume tacitly that the first two models can be combined and analyze parameters deviations in one combined model. However, the role of the first two models can be asymmetric if some optimization of the decision is performed on the first model. We extend this framework, intended originally for single criteria (scalar) optimization to multiple criteria (vector) optimization. The proposed approach is illustrated by diverse examples.

Rehabilitation of Lake Ontario: the Role of Nutrient Reduction and Food Web Dynamics

1991 ◽  
Vol 48 (8) ◽  
pp. 1574-1580 ◽  
Author(s):  
John H. Hartig ◽  
James F. Kitchell ◽  
Donald Scavia ◽  
Stephen B. Brandt
Keyword(s):  
Water Quality ◽  
Great Lakes ◽  
Food Web ◽  
Toxic Substance ◽  
Lake Ontario ◽  
The United States ◽  
Food Web Dynamics ◽  
Food Web Interactions ◽  
The Impact

The Laurentian Great Lakes have a complex history of changes due to eutrophication, invasion of exotic species, and fisheries and phosphorus management practices. Remedial actions have reduced nutrient loadings and enhanced the role of food web interactions in improving water quality. Workshops sponsored through the United States – Canada international Joint Commission have addressed the relative importance of nutrient abatement and/or food web manipulation in affecting water quality trends. Both controls have combined to enhance water clarity in Lake Michigan. Lake Ontario has already exhibited the effects of nutrient controls and may be on the verge of manifesting food web controls. Research and monitoring recommendations to elucidate the effects of nutrient and food web controls include the following: (1) water quality and fisheries agencies must coordinate monitoring activities, standardize techniques, and establish and maintain long-term data sets to evaluate the effects of water quality and fisheries programs separately and together; (2) controlled, mesoscale, whole-system experiments should be performed to quantify rates (e.g. growth, predation, etc.) of food web interactions; and (3) the scientific community should promote research which quantifies the impact of changes in food web dynamics on changes in toxic substance levels in Great Lakes fishes.

Does psychoeducation influence carers' attitudes to treatment of schizophrenia?

2007 ◽  
Vol 24 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Stephen McWilliams ◽  
Shane Hill ◽  
Nora Mannion ◽  
Anthony Kinsella ◽  
Eadbhard O'Callaghan
Keyword(s):  
Locus Of Control ◽  
Patient Outcomes ◽  
Standard Care ◽  
Family Attitudes ◽  
Before And After ◽  
Health And Illness ◽  
Illness Attitudes ◽  
The Impact ◽  
Harmful Effects

AbstractObjective: To measure the impact of a six-week Carer Psychoeducation Program (CPP) on factors that influence attitudes towards treatment among carers and relatives of people suffering from schizophrenia. We also examined which specific attitudes to treatment the CPP had the most effect on.Method: Between 2002 and 2004, all patients and their relatives continued standard care. During this period, we conducted a historically-controlled open trial, in which 64 relatives completed a 17-item adapted version of the Drug Attitudes Inventory (DAI) before and after the CPP.Results: Attitudes to treatment improved significantly overall (p < 0.001), an improvement most marked in terms of attitudes to health and illness, attitudes towards the physician and attitudes towards the potentially harmful effects of treatment. No statistically significant improvement was found, however, in attitudes to locus of control or the preventative role of treatment.Conclusion: A CPP specifically improves family attitudes towards treatment. This finding is clinically important because such attitudes influence adherence which, in turn, influences outcome. The fact that certain attitudes are influenced by the CPP, while others are not, may help to explain the mechanism through which patient outcomes improve.

scholarly journals The emerging role of the first 17 amino acids of huntingtin in Huntington’s disease

2015 ◽  
Vol 6 (1) ◽  
pp. 33-46 ◽  
Author(s):  
James R. Arndt ◽  
Maxmore Chaibva ◽  
Justin Legleiter
Keyword(s):  
Amino Acids ◽  
Huntington's Disease ◽  
Huntington’S Disease ◽  
Aggregate Stability ◽  
Biochemical Properties ◽  
Critical Threshold ◽  
N Terminus ◽  
The Impact ◽  
Polyq Domain

AbstractHuntington’s disease (HD) is caused by a polyglutamine (polyQ) domain that is expanded beyond a critical threshold near the N-terminus of the huntingtin (htt) protein, directly leading to htt aggregation. While full-length htt is a large (on the order of ∼350 kDa) protein, it is proteolyzed into a variety of N-terminal fragments that accumulate in oligomers, fibrils, and larger aggregates. It is clear that polyQ length is a key determinant of htt aggregation and toxicity. However, the flanking sequences around the polyQ domain, such as the first 17 amino acids on the N terminus (Nt17), influence aggregation, aggregate stability, influence other important biochemical properties of the protein and ultimately its role in pathogenesis. Here, we review the impact of Nt17 on htt aggregation mechanisms and kinetics, structural properties of Nt17 in both monomeric and aggregate forms, the potential role of posttranslational modifications (PTMs) that occur in Nt17 in HD, and the function of Nt17 as a membrane targeting domain.

scholarly journals E2f3 is critical for normal cellular proliferation

2000 ◽  
Vol 14 (6) ◽  
pp. 690-703 ◽  
Author(s):  
Patrick O. Humbert ◽  
Raluca Verona ◽  
Jeffrey M. Trimarchi ◽  
Catherine Rogers ◽  
Savita Dandapani ◽  
...  
Keyword(s):  
Transcriptional Activation ◽  
Cellular Proliferation ◽  
Threshold Level ◽  
Critical Threshold ◽  
Cellular Immortalization ◽  
Proliferation And Differentiation ◽  
Rate Limiting ◽  
Deficient Mice

E2F is a family of transcription factors that regulate both cellular proliferation and differentiation. To establish the role of E2F3 in vivo, we generated an E2f3 mutant mouse strain. E2F3-deficient mice arise at one-quarter of the expected frequency, demonstrating that E2F3 is important for normal development. To determine the molecular consequences of E2F3 deficiency, we analyzed the properties of embryonic fibroblasts derived from E2f3 mutant mice. Mutation of E2f3 dramatically impairs the mitogen-induced, transcriptional activation of numerous E2F-responsive genes. We have been able to identify a number of genes, including B-myb,cyclin A, cdc2, cdc6, and DHFR, whose expression is dependent on the presence of E2F3 but not E2F1. We further show that a critical threshold level of one or more of the E2F3-regulated genes determines the timing of the G1/S transition, the rate of DNA synthesis, and thereby the rate of cellular proliferation. Finally, we show that E2F3 is not required for cellular immortalization but is rate limiting for the proliferation of the resulting tumor cell lines. We conclude that E2F3 is critical for the transcriptional activation of genes that control the rate of proliferation of both primary and tumor cells.

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