194 research outputs found
The use of coal in a solid phase reduction of iron oxide
The results of the research process of producing metalized products by solid-phase reduction of iron using solid carbonaceous reducing agents. Thermodynamic modeling was carried out on the model of the unit the Fe-C-O and system with iron ore and coal. As a result of modeling the thermodynamic boundary reducing, oxidizing, and transition areas and the value of the ratio of carbon and oxygen in the system. Simulation of real systems carried out with the gas phase obtained in the pyrolys of coal. The simulation results allow to determine the optimal cost of coal required for complete reduction of iron ore from a given composition. The kinetics of the processes of solid-phase reduction of iron using coal of various technological brands
Conductive heat transfer in a gas confined between two concentric spheres: From free-molecular to continuum flow regime
Acute kidney disease and renal recovery : consensus report of the Acute Disease Quality Initiative (ADQI) 16 Workgroup
Consensus definitions have been reached for both acute kidney injury (AKI) and chronic kidney disease (CKD) and these definitions are now routinely used in research and clinical practice. The KDIGO guideline defines AKI as an abrupt decrease in kidney function occurring over 7 days or less, whereas CKD is defined by the persistence of kidney disease for a period of > 90 days. AKI and CKD are increasingly recognized as related entities and in some instances probably represent a continuum of the disease process. For patients in whom pathophysiologic processes are ongoing, the term acute kidney disease (AKD) has been proposed to define the course of disease after AKI; however, definitions of AKD and strategies for the management of patients with AKD are not currently available. In this consensus statement, the Acute Disease Quality Initiative (ADQI) proposes definitions, staging criteria for AKD, and strategies for the management of affected patients. We also make recommendations for areas of future research, which aim to improve understanding of the underlying processes and improve outcomes for patients with AKD
Agri-Environmental Policy Measures in Israel: The Potential of Using Market-Oriented Instruments
This paper examines the possibilities of developing agri-environmental policy measures in Israel, focusing on market-oriented instruments. A conceptual framework for developing agri-environmental policy measures is presented, first in very broad lines (mandatory regulations, economic instruments and advisory measures) and subsequently focusing on economic instruments, and specifically, on market-oriented ones. Two criteria of choice between the measures are suggested: their contribution to improving the effectiveness of the policy; and the feasibility of their implementation. This is the framework used for analyzing agri-environmental measures in Israel. Israel currently implements a mix of mandatory regulations, economic instruments and advisory measures to promote the agri-environment. The use of additional economic instruments may improve the effectiveness of the policy. When comparing the effectiveness of various economic measures, we found that the feasibility of implementation of market-oriented instruments is greater, due to the Israeli publicâs preference for strengthening market orientation in the agricultural sector. Four market-oriented instruments were practiced in a pilot project conducted in an Israeli rural area. We found that in this case study, the institutional feasibility and acceptance by stakeholders were the major parameters influencing the implementation of the market-oriented instruments, whereas the instrumentsâ contribution to enhancing the ecological or economic effectiveness were hardly considered by the stakeholders as arguments in favor of their use
Variability in Working Memory Performance Explained by Epistasis vs Polygenic Scores in the ZNF804A Pathway
Importance: We investigated the variation in neuropsychological function explained by risk alleles at the psychosis susceptibility gene ZNF804A and its interacting partners using single nucleotide polymorphisms (SNPs), polygenic scores, and epistatic analyses. Of particular importance was the relative contribution of the polygenic score vs epistasis in variation explained.
Objectives To (1) assess the association between SNPs in ZNF804A and the ZNF804A polygenic score with measures of cognition in cases with psychosis and (2) assess whether epistasis within the ZNF804A pathway could explain additional variation above and beyond that explained by the polygenic score.
Design, Setting, and Participants: Patients with psychosis (nâ=â424) were assessed in areas of cognitive ability impaired in schizophrenia including IQ, memory, attention, and social cognition. We used the Psychiatric GWAS Consortium 1 schizophrenia genome-wide association study to calculate a polygenic score based on identified risk variants within this genetic pathway. Cognitive measures significantly associated with the polygenic score were tested for an epistatic component using a training set (nâ=â170), which was used to develop linear regression models containing the polygenic score and 2-SNP interactions. The best-fitting models were tested for replication in 2 independent test sets of cases: (1) 170 individuals with schizophrenia or schizoaffective disorder and (2) 84 patients with broad psychosis (including bipolar disorder, major depressive disorder, and other psychosis).
Main Outcomes and Measures: Participants completed a neuropsychological assessment battery designed to target the cognitive deficits of schizophrenia including general cognitive function, episodic memory, working memory, attentional control, and social cognition.
Results: Higher polygenic scores were associated with poorer performance among patients on IQ, memory, and social cognition, explaining 1% to 3% of variation on these scores (range, Pâ=â.01 to .03). Using a narrow psychosis training set and independent test sets of narrow phenotype psychosis (schizophrenia and schizoaffective disorder), broad psychosis, and control participants (nâ=â89), the addition of 2 interaction terms containing 2 SNPs each increased the R2 for spatial working memory strategy in the independent psychosis test sets from 1.2% using the polygenic score only to 4.8% (Pâ=â.11 and .001, respectively) but did not explain additional variation in control participants.
Conclusions and Relevance: These data support a role for the ZNF804A pathway in IQ, memory, and social cognition in cases. Furthermore, we showed that epistasis increases the variation explained above the contribution of the polygenic score
Comprehensive Gene-Based Association Study of a Chromosome 20 Linked Region Implicates Novel Risk Loci for Depressive Symptoms in Psychotic Illness
Background
Prior genomewide scans of schizophrenia support evidence of linkage to regions of chromosome 20. However, association analyses have yet to provide support for any etiologically relevant variants. Methods
We analyzed 2988 LD-tagging single nucleotide polymorphisms (SNPs) in 327 genes on chromosome 20, to test for association with schizophrenia in 270 Irish high-density families (ISHDSF, N = 270 families, 1408 subjects). These SNPs were genotyped using an Illumina iSelect genotyping array which employs the Infinium assay. Given a previous report of novel linkage with chromosome 20p using latent classes of psychotic illness in this sample, association analysis was also conducted for each of five factor-derived scores based on the Operational Criteria Checklist for Psychotic Illness (delusions, hallucinations, mania, depression, and negative symptoms). Tests of association were conducted using the PDTPHASE and QPDTPHASE packages of UNPHASED. Empirical estimates of gene-wise significance were obtained by adaptive permutation of a) the smallest observed P-value and b) the threshold-truncated product of P-values for each locus. Results
While no single variant was significant after LD-corrected Bonferroni-correction, our gene-dropping analyses identified loci which exceeded empirical significance criteria for both gene-based tests. Namely, R3HDML and C20orf39 are significantly associated with depressive symptoms of schizophrenia (PempP-value and truncated-product methods, respectively. Conclusions
Using a gene-based approach to family-based association, R3HDML and C20orf39 were found to be significantly associated with clinical dimensions of schizophrenia. These findings demonstrate the efficacy of gene-based analysis and support previous evidence that chromosome 20 may harbor schizophrenia susceptibility or modifier loci
Speech, truth and liberty: Bentham to John Stuart Mill
Benthamâs Utilitarianism transforms earlier free speech doctrine in the service of the pursuit of truth and the control of government, preserving the distinction between statements of opinion and of fact and awarding the latter a lesser degree of protection. The work of James Mill and the early writings of John Stuart Mill retain this distinction, but their accounts are weighed down by the problems of a direct Utilitarian approach, in their consequentialist balancing of different values against each other, and in their dependence on a majoritarian epistemology and their commitment to a naive progressive optimism. Mill goes on in On Liberty to address and resolve these problems on the basis of a new justification for free speech as free deliberative thought. I argue that, contrary to most interpretations, his new justification leaves untouched the basic distinction between absolutely protected expressions of opinion and only functionally and contingently protected assertions of fact, leaving room for restrictions on factual statements, especially when untrue
Emotional Processing in Individuals with Substance Use Disorder and Posttraumatic Stress Disorder
The Usability of E-learning Platforms in Higher Education: A Systematic Mapping Study
The use of e-learning in higher education has increased significantly in recent years, which has led to several studies being conducted to investigate the usability of the platforms that support it. A variety of different usability evaluation methods and attributes have been used, and it has therefore become important to start reviewing this work in a systematic way to determine how the field has developed in the last 15 years. This paper describes a systematic mapping study that performed searches on five electronic libraries to identify usability issues and methods that have been used to evaluate e-learning platforms. Sixty-one papers were selected and analysed, with the majority of studies using a simple research design reliant on questionnaires. The usability attributes measured were mostly related to effectiveness, satisfaction, efficiency, and perceived ease of use. Furthermore, several research gaps have been identified and recommendations have been made for further work in the area of the usability of online learning
- âŠ