矿热电炉改造为贫化电炉的生产实践

云铜股份公司艾萨炉投产后,2#电炉原来的熔炼功能已经改变为贫化功能。本文介绍贫化电炉的设计、投产过程中出现的问题和解决办法以及投产半年来的生产状况。     

Transforming odds ratios into correlations for meta-analytic research.

Comments on an article by Block and Crain (see record 2007-04834-015) in which they stated, "There is no data transformation that converts an odds ratio or relative risk into a correlation. One needs more data". The purpose of this comment is to explain how an odds ratio or relative risk can be transformed to approximate a product-moment correlation. Such transformations have important applications in meta-analytic research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transforming schools into communities of thinking and learning about serious matters.

In this article, a program of research known as Fostering Communities of Learners is described. This program is in place in several schools and classrooms serving inner-city students from 6 to 12 years of age. Based on theoretical advances in cognitive and developmental psychology, the program is successful at improving both literacy skills and domain-area subject matter knowledge (e.g., environmental science and biology). Building on young children's emergent strategic and metacognitive knowledge, together with their skeletal biological theories, the program leads children to discover the deep principles of the domain and to develop flexible learning and inquiry strategies of wide applicability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

白磷转化为红磷过程中爆炸原因探析

本文通过对工艺中白磷和红磷的结构及其有关性质的分析,提出和 白磷转化为工磷的模拟过程,从而找到了磷转化时发生爆炸或冲料的原因并探讨了解决办法。     

Transforming Hematite into Magnetite Using Mechanochemical Approach as a Pretreatment of Oolitic Hematite

Potential transformation of oolitic hematite into magnetite by mixing iron powder using the mechanochemical method has been achieved and discussed in this paper. The phase transition of pure hematite in the preliminary test was identified by X-ray diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. The experimental results have shown that the crystallographic planes of magnetite, (220), (311), (400), and (511) were observed clearly in the Fe/α-Fe₂O₃ mixture after milling for 15 h, indicating that α-Fe₂O₃ had been effectively transformed into Fe₃O₄. The diffraction peaks of magnetite were also observed at d = 0.29605 nm (2θ = 30.163°), 0.25226 nm (2θ = 35.559°), 0.24156 nm (2θ = 37.190°), and 0.20898 nm (2θ = 43.458°) after 13 h milling-time. It suggests that the oolitic hematite is transformed into magnetite successfully by mechanochemical processing. The processing might be applied potentially for the magnetic separation of oolitic hematite.     

济钢4.3m顶装焦炉改捣固焦炉的实践

为有效降低配煤成本,济钢通过采取改造配合煤粉碎系统、新建小侧装煤塔、改进除尘方式、新增机械设备等措施将4.3 m顶装焦炉改造为捣固焦炉。改造后,在保证同样焦炭质量的前提下,多用30%~40%的高挥发分弱黏性煤及部分非黏结性煤,扩大了炼焦用煤源,配合煤成本降低30多元/t,且保持炉体不变。     

Measuring diagnostic agreement.

Diagnostic agreement tests the reliability and concordance of diagnostic systems. The introduction of measures of agreement with reputations for baserate independence (e.g., Yule's Y and Q), and new studies occasioned by the publication of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) and the International Classification of Diseases—10 (ICD-10, World Health Organization, 1992) make it necessary to study the relationship of illness baserates to measures of agreement. Testing diagnostic concordance for diagnoses of drug dependence from the third edition of the DSM (American Psychiatric Association, 1980) versus DSM-IV diagnoses of drug dependence under 3 baserate conditions, it was found that Yule's Y and Q proved as vulnerable to differences in baserates as kappa or percent agreement and that specificity covaried with baserate rather than being fixed, as most theoretical discussions assume. The uncritical use of Y and Q, therefore, is likely to lead to optimistic interpretations of agreement. Kappa should be preferred for most purposes, although an adjustment to the computational formulas for Y and Q is presented that can diminish their positive bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interobserver relational agreement.

Assessing interobserver agreement calls for measuring the degree to which numbers generated by one observer match those generated by another observer. However, for all scales of measurement save one, the absolute scale, using interobserver agreement as a measure of interobserver consistency is too strict because the observers might disagree only on empirically meaningless relationships. Two observers that are rating behaviors on an ordinal scale need only to generate orders that agree, not ratings that agree. This concept is formalized into a notion of relational agreement. Observers need to agree only on empirically meaningful (in a measurement theoretical sense) relationships. Those relationships that are empirically meaningful change as a function of the scale of measurement in use. A class of measures for measuring relational agreement (based on F. E. Zegers and J. M. F. ten Berge [see PA, Vol 72:24356]) is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Transforming growth factor-beta 3

Transforming Growth Factor-Beta (TGF-beta) is the general name for a family of naturally-occurring polypeptides which have multiple regulatory effects on cell proliferation and differentiation. Over the last decade it has become apparent that TGF-betas can be produced by most cell types and exert a wide range of effects in a context-dependent autocrine, paracrine or endocrine fashion via interactions with distinct receptors on the cell surface. This review summarizes current knowledge concerning the molecular and cellular biology of TGF-beta 3, the most recently described mammalian isoform, and focuses on those physiological actions which may lead to clinical applications, particularly in the indication areas of wound healing and chemoprotection.     

Assessing interrater agreement from dependent data

The effects of riluzole, a neuroprotective drug, on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels in rat dorsal root ganglion neurons were studied using the whole-cell patch clamp technique. At the resting potential, riluzole preferentially blocked TTX-S sodium channels, whereas at more negative potentials, it blocked both types of sodium channels almost equally. The apparent dissociation constants for riluzole to block TTX-S and TTX-R sodium channels in their resting state were 90 and 143 microM, respectively. Riluzole shifted the voltage dependence of activation of TTX-R sodium channels in the depolarizing direction more than that of TTX-S sodium channels. The voltage dependence of the fast inactivation of both types of sodium channels was shifted in the hyperpolarizing direction in a dose-dependent manner, and the apparent dissociation constants for riluzole to block the inactivated channels were estimated to be 2 and 3 microM for the TTX-S and TTX-R sodium channels, respectively, indicating a much higher affinity for the inactivated channels than for the resting channels. Riluzole was equally effective in blocking both types of sodium channels in their slow inactivated state. Since more TTX-S channels are inactivated than TTX-R channels at the resting potential, riluzole blocks TTX-S sodium channels more potently than TTX-R sodium channels. It was concluded that one of the mechanisms by which riluzole exerts its neuroprotective action is to preferentially block the inactivated sodium channel of damaged or depolarized neurons under ischemic conditions, thereby suppressing excess stimulation of the glutamatergic receptors and massive influx of Ca++.     

Validity inferences from interobserver agreement.

Methods for measuring rater agreement and making inferences about the accuracy of dichotomous ratings from agreement data are described. The first section presents a probability model related to latent class analysis that is applicable when ratings are based on a discrete trait. The second section extends these methods to situations in which ratings are based on a continuous trait, using a model related to signal detection theory and item response theory. The values obtained by these methods provide either direct or upper-bounds estimates of rating accuracy, depending upon the nature of the rating process. Formulas are shown for combining the opinions of multiple raters to classify cases with greater accuracy than simple majority or unanimous opinion decision rules allow. Additional technical refinements of the probabilty modeling approach are possible, and it promises to lead to many improvements in the ways that ratings by multiple raters are analyzed and used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measurement reliability and agreement in psychiatry

Age-specific mortality rates decelerate at older ages in both genetically homogenous and heterogeneous populations of Drosophila. One explanation proposed for deceleration is population heterogeneity. This hypothesis suggests that a population consists of sub-populations that differ in mortality characteristics and that the deceleration is the result of selective survival of stronger individuals. Here we describe an experiment that fractionates populations into several sub-populations without changing the physiological characteristics of the post-fractionated populations. Through a careful process of selection of Drosophila eggs, larvae, pupae and adults, we attempt to reduce as much as possible the degree of pre-adult, environmentally induced heterogeneity among individuals of a genetically identical cohort. We then ask whether such cohorts, when compared to non-fractionated populations, exhibit a lesser degree of mortality deceleration at advanced ages. From a total of 106 fractionated and control populations, consisting of 51331 individuals, 101 populations (93% of the fractionated populations and 100% of the control populations) exhibit a significant amount of mortality deceleration late in life. These observations suggest that environmental heterogeneity accrued during larval development is not a major factor contributing to mortality deceleration at older ages.     

Parent-victim agreement in adolescent suicide research

It is known that transcranial magnetic stimulation (TMS) administered over the occipital pole suppresses recognition of visual objects. Our aim was to ascertain whether this suppression can be interpreted as a change in visual contrast threshold. Four subjects detected the orientation of an U-shaped hook flashed for 21 ms. Under control conditions, mean contrast threshold was found at 0.88 log units Weber contrast. Thresholds were raised if TMS was applied 40-200 ms after the visual stimulus. Maximum elevation was 1.67 log units under TMS at 120 ms stimulus onset asynchrony. This phenomenon can be interpreted as a reduction in signal-to-noise ratio of the visual stimuli by TMS, which can be compensated for by increasing the contrast of the stimuli.     

Interrater agreement and predictive validity.

Ss were 549 illiterate Iranian truck drivers rated for intelligence and given an individual intelligence test. To relate unreliability of ratings to validity, correlations were made between intelligence test scores and 4 groups of criterion ratings differing in reliability. The authors conclude that in the construction of rating scales, weighting of ratings by their agreement is better than by their disagreement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Counselor-client agreement on session impact.

We propose a new framework for understanding studies of counselor–client agreement about their counseling. The framework includes five factors: the scope of counseling being studied (process, impact, or outcome), the dimension (index) being rated (in this study, session Depth, Smoothness, Positivity, or Arousal), the measure used to assess agreement (correlations or absolute differences), the level at which the analysis is conducted (session, client, or counselor), and the type of agreement—(a) consensus, the similarity of counselors' own ratings to clients' own ratings; (b) counselor awareness, the similarity of counselors' perceptions of their clients to clients' own ratings; (c) client awareness, the similarity of counselors' own ratings to clients' perceptions of their counselors; and (d) matched awareness, the similarity of counselors' perceptions of their clients to clients' perceptions of their counselors. In a study of session impact (scope), degree of agreement was found to vary substantially with each of the other factors—type of agreement, dimension rated, measure of agreement, and level of analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)