Impact of leadership style and emotions on subordinate performance

This article examines whether the emotions of frustration and optimism mediate, fully or partially, the relationship between leadership style and subordinate performance in the context of structural equation modeling. The findings show that transformational leadership has a significant direct influence on frustration and optimism, with the negative influence of frustration having a stronger effect on performance than the positive influence of optimism. Frustration and optimism are found to have a direct influence on performance, and the emotions, frustration and optimism, fully mediate the relationship between transformational leadership and performance. Thus, the effect of transformational leadership style on performance is significant, but indirect. (C) 2002 Elsevier Science Inc. All rights reserved.

Exact theory of sedimentation equilibrium made useful

The exact description of the thermodynamics of solutions has been used to describe, without approximation, the distribution of all the components of an incompressible solution in a centrifuge cell at sedimentation equilibrium. Thermodynamic parameters describing the interactions between solute components of known molar mass can be obtained by direct analysis of the experimental data. Interpretation of the measured thermodynamic parameters in terms of molecular interactions requires that an arbitrary distinction be made between nonassociative forces, like hard-sphere volume-exclusion and mean-field electrostatic repulsion or attraction, and specific short-range forces of association that give rise to the formation of molecular aggregates. Provided the former can be accounted for adequately, the effects of the latter can be elucidated in the form of good estimates of the equilibrium constants for the reactions of aggregation.

Dimensionality and clinical importance of pain and disability in hand osteoarthritis: Development of the Australian/Canadian (AUSCAN) Osteoarthritis Hand Index

Objective: To develop a reliable, valid, and responsive self-administered questionnaire to probe pain, stiffness and physical disability in patients with osteoarthritis (OA) of the hand. Design: In order to assess the dimensionality of the symptomatology of hand OA, a self-administered questionnaire was developed to probe various aspects of pain (10 items), stiffness (two items), and physical function (83 items). The question inventory was generated from eight existing health status measures and an interactive process involving four rheumatologists, two physiotherapists, and an orthopaedic surgeon. Results: Face-to-face interviews were conducted with 50 OA hand patients; 39 females and 11 males with mean age 62.8 years and mean disease duration 9.4 years. Items retained were those which fulfilled specified selection criteria: prevalence greater than or equal to60% and mean importance score approximating or exceeding 2.0 Item exclusion criteria included low prevalence, gender-based, ambiguous, duplicates or similarities, alternatives, composite items, and items that were too restrictive. This process resulted in five pain, one stiffness and nine function items which have been proposed for incorporation in the AUSCAN Index. Conclusions: Using a traditional development strategy, we have constructed a self-administered multi-dimensional outcome measure for assessing hand OA. The next stage includes reliability, validity and responsiveness testing of the 15-item questionnaire. (C) 2002 OsteoArthritis Research Society Intenational. Published by Elsevier Science Ltd. All rights reserved.

Intraindividual allometric development of aerobic power in 8- to 16-year-old boys

Purpose: The aims of this study are two-fold: first, to analyze intraindividual allometric development of aerobic power of 73 boys followed at annual intervals from 8 to 16 yr, and second, to relate scaled aerobic power with level of habitual physical activity and biological maturity status. Methods: Peak (V) over dot O-2 (treadmill), height, and body mass were measured. Biological maturity was based on age at peak height velocity (PHV) and level of physical activity was based on five assessments between 11 and 15 yr and at 17 yr. Interindividual and intraindividual allometric coefficients were calculated. Multilevel modeling was applied to verify if maturity status and activity explain a significant proportion of peak (V) over dot O-2 after controlling for other explanatory characteristics. Results: At most age levels, interindividual allometry coefficients for body mass exceed k = 0.750. Intraindividual coefficients of peak (V) over dot O-2 by body mass vary widely and range from k' = 0,555 to k' = 1,178. Late maturing boys have smaller k' coefficients than early maturing boys. Conclusion: Peak (V) over dot O-2 is largely explained by body mass, but activity level and its interaction with maturity status contribute independently to peak (V) over dot O-2 even after adjusting for body mass.

Inferring genome trees by using a filter to eliminate phylogenetically discordant sequences and a distance matrix based on mean normalized BLASTP scores

Darwin's paradigm holds that the diversity of present-day organisms has arisen via a process of genetic descent with modification, as on a bifurcating tree. Evidence is accumulating that genes are sometimes transferred not along lineages but rather across lineages. To the extent that this is so, Darwin's paradigm can apply only imperfectly to genomes, potentially complicating or perhaps undermining attempts to reconstruct historical relationships among genomes (i.e., a genome tree). Whether most genes in a genome have arisen via treelike (vertical) descent or by lateral transfer across lineages can be tested if enough complete genome sequences are used. We define a phylogenetically discordant sequence (PDS) as an open reading frame (ORF) that exhibits patterns of similarity relationships statistically distinguishable from those of most other ORFs in the same genome. PDSs represent between 6.0 and 16.8% (mean, 10.8%) of the analyzable ORFs in the genomes of 28 bacteria, eight archaea, and one eukaryote (Saccharomyces cerevisiae). In this study we developed and assessed a distance-based approach, based on mean pairwise sequence similarity, for generating genome trees. Exclusion of PDSs improved bootstrap support for basal nodes but altered few topological features, indicating that there is little systematic bias among PDSs. Many but not all features of the genome tree from which PDSs were excluded are consistent with the 16S rRNA tree.

Liver transplantation as a therapeutic option for hepatocellular carcinoma

Better outcomes of the patients receiving liver transplantation for viral hepatitis and hepatocellular carcinoma (HCC) are achieved by improved patient selection and perioperative treatment with antiviral agents including lamivudine, ribavirin and interferon. Patient selection is accomplished by high-quality imaging as well as exclusion of patients with large tumors, obvious extrahepatic disease or macroscopic vascular invasion. Using such criteria, a 5-year survival of 92% has been reached in the Queensland Liver Transplant Service on a small number of highly selected patients with HCC. The treatment algorithm of Makuuchi has guided us in recommending resection, estimating to what extent the liver resection can be performed safely, and timing liver transplantation when it is the only option. Adult-to-adult living-donor liver transplantation is being performed safely in many centers worldwide. The transplantation of liver from living donors to HCC patients, when standard criteria for the likelihood of good outcomes are fulfilled, will increase in Japan in the near future. Copyright (C) 2002 S. Karger AG, Basel.

The Limits of Rational Choice: New Institutionalism in the Test Bed of Central Banking Politics in Australia

This paper tests the explanatory capacities of different versions of new institutionalism by examining the Australian case of a general transition in central banking practice and monetary politics: namely, the increased emphasis on low inflation and central bank independence. Standard versions of rational choice institutionalism largely dominate the literature on the politics of central banking, but this approach (here termed RC1) fails to account for Australian empirics. RC1 has a tendency to establish actor preferences exogenously to the analysis; actors' motives are also assumed a priori; actor's preferences are depicted in relatively static, ahistorical terms. And there is the tendency, even a methodological requirement, to assume relatively simple motives and preference sets among actors, in part because of the game theoretic nature of RC1 reasoning. It is possible to build a more accurate rational choice model by re-specifying and essentially updating the context, incentives and choice sets that have driven rational choice in this case. Enter RC2. However, this move subtly introduces methodological shifts and new theoretical challenges. By contrast, historical institutionalism uses an inductive methodology. Compared with deduction, it is arguably better able to deal with complexity and nuance. It also utilises a dynamic, historical approach, and specifies (dynamically) endogenous preference formation by interpretive actors. Historical institutionalism is also able to more easily incorporate a wider set of key explanatory variables and incorporate wider social aggregates. Hence, it is argued that historical institutionalism is the preferred explanatory theory and methodology in this case.

Distribution kinetics of solutes in the isolated in-situ perfused rat head using the multiple indicator dilution technique and a physiological two-barrier model

The purpose of this study was to determine the pharmacokinetics of [C-14]diclofenac, [C-14]salicylate and [H-3]clonidine using a single pass rat head perfusion preparation. The head was perfused with 3-[N-morpholino] propane-sulfonic acid-buffered Ringer's solution. Tc-99m-red blood cells and a drug were injected in a bolus into the internal carotid artery and collected from the posterior facial vein over 28 min. A two-barrier stochastic organ model was used to estimate the statistical moments of the solutes. Plasma, interstitial and cellular distribution volumes for the solutes ranged from 1.0 mL (diclofenac) to 1.6 mL (salicylate), 2.0 mL (diclofenac) to 4.2 mL (water) and 3.9 mL (salicylate) to 20.9 mL (diclofenac), respectively. A comparison of these volumes to water indicated some exclusion of the drugs from the interstitial space and salicylate from the cellular space. Permeability-surface area (PS) products calculated from plasma to interstitial fluid permeation clearances (CLPI) (range 0.02-0.40 mL s(-1)) and fractions of solute unbound in the perfusate were in the order: diclofenac>salicylate >clonidine>sucrose (from 41.8 to 0.10 mL s(-1)). The slow efflux of diclofenac, compared with clonidine and salicylate, may be related to its low average unbound fraction in the cells. This work accounts for the tail of disposition curves in describing pharmacokinetics in the head.

Distributional profiles of homologous open reading frames among bacterial phyla: implications for vertical and lateral transmission

If open reading frames (ORFs) have been transmitted primarily by vertical descent, the distributional profile of orthologues of each ORF should be congruent with the organismal tree or a subtree thereof. Distributional patterns not reconciled parsimoniously with tree-like descent and loss are prima facie evidence of lateral gene transfer. Herein, a rigorous criterion for recognizing ORF distributions is described and implemented; it does not require the inference of phylogenetic trees, nor does it assume any specific tree. Because lineage-specific differences in rates of sequence change can also generate unexpected distributional patterns, rate artefacts, were controlled for by requiring pairwise matches between ORFs to exceed a rigorous inclusion threshold, but absence of a match was assessed against a more-permissive exclusion threshold. Applying this dual-threshold criterion to cross-domain and cross-phylum distributional patterns for ORFs in 23 bacterial genomes, a relative abundance of ORFs was observed that find a match in exactly seven other bacterial phyla; 94-99% of these ORFs also find matches among the Archaea and/or Eukarya. In the larger (and some smaller) bacterial genomes, ORFs that find matches in exactly one other bacterial phylum are also relatively abundant, but fewer of these have non-bacterial homologues; most of their matches within the Bacteria are to the Proteobacteria and/or Firmicutes, which cannot be sister lineages to all bacteria. ORFs that are neither distributed universally among the Bacteria, nor necessarily shared with topologically adjacent lineages, are preferentially enriched in large bacterial genomes.

Plasma growth hormone and growth hormone-binding protein during development in the marsupial brushtail possum (Trichosurus vulpecula)

Plasma concentrations of growth hormone (GH) were measured in the brushtail possum (Trichosurus vulpecula) pouch young from 25 through to 198 days post-partum (n=71). GH concentrations were highest early in pouch life (around 100 ng/ml), and thereafter declined in an exponential fashion to reach adult concentrations (10.8 +/- 1.8 ng/ml; n=21) by approximately 121-145 days post-partum, one to two months before the young is weaned. Growth hormone-binding protein (GHBP), which has been shown to modify the cellular actions of GH in eutherian mammals, was identified for the first time in a marsupial. Based on size exclusion gel filtration, possum GHBP had an estimated molecular mass of approximate to 65 kDa, similar to that identified in other mammalian species, and binding of I-125-labelled human GH (hGH) was displaced by excess hGH (20 mug). An immunoprecipitation method, in which plasma GHBP was rendered polyethylene glycol precipitable with a monoclonal antibody to the rabbit GHBP/GH receptor (MAb 43) and labelled with I-125-hGH, was used to quantitate plasma GHBP by Scatchard analysis in the developing (pooled plasma samples) and adult (individual animals) possums. Binding affinity (K-a) values in pouch young aged between 45 and 54 and 144 and 153 days post-partum varied between 1.0 and 2.4 x 10(9)/M, which was slightly higher than that in adult plasma (0.96 +/- 0.2 x 10(9)/M, n = 6). Binding capacity (B-max) values increased from non-detectable levels in animals aged 25-38 days post-partum to reach concentrations around half that seen in the adult (1.4 +/- 0.2 x 10(-9) M) by about 117 days post-partum and remained at this level until 153 days post-partum. Therefore, in early pouch life when plasma GH concentrations are highest, the very low concentrations of GHBP are unlikely to be important in terms of competing with GH-receptor for ligand or altering the half-life of circulating GH.

An investigation into the possible inhibitory effects of white cypress pine (Callitris glaucophylla) litter on the germination and growth of associated ground cover species

White cypress-pine stands typically support sparse densities of shrubs and grasses. The commonly held opinion is that leaching of allelopathic chemical compounds from cypress-pine litter partly facilitates this exclusion. Germination and growth of cypress pine seedlings do not appear to be similarly affected. This study set out to determine whether cypress litter had a differential effect on germination and growth of cypress-pine seedlings and on associated ground-cover species. Glasshouse trials comparing seedling emergence under cypress- and artificial-litter layers were undertaken. Cypress-pine litter did not have an inhibitory effect on the germination or growth of ground-cover species. In most cases, seedling emergence was facilitated by the application of cypress-pine litter due to its ability to increase the water holding capacity of the underlying soil. Cypress litter did not promote growth of its own seedlings over its competitors except on coarse-textured soils where it provided an ameliorative function to water stress due to the soil's reduced water holding capacity. The inhibition of ground-cover species' germination and growth in pure cypress stands was suggested to be the result of high below-ground resource competition due to the pine's expansive root morphology.

Bridging the gap between different statistical approaches: An integrated framework for modelling

This paper proposes a template for modelling complex datasets that integrates traditional statistical modelling approaches with more recent advances in statistics and modelling through an exploratory framework. Our approach builds on the well-known and long standing traditional idea of 'good practice in statistics' by establishing a comprehensive framework for modelling that focuses on exploration, prediction, interpretation and reliability assessment, a relatively new idea that allows individual assessment of predictions. The integrated framework we present comprises two stages. The first involves the use of exploratory methods to help visually understand the data and identify a parsimonious set of explanatory variables. The second encompasses a two step modelling process, where the use of non-parametric methods such as decision trees and generalized additive models are promoted to identify important variables and their modelling relationship with the response before a final predictive model is considered. We focus on fitting the predictive model using parametric, non-parametric and Bayesian approaches. This paper is motivated by a medical problem where interest focuses on developing a risk stratification system for morbidity of 1,710 cardiac patients given a suite of demographic, clinical and preoperative variables. Although the methods we use are applied specifically to this case study, these methods can be applied across any field, irrespective of the type of response.

The development of chromatography for the characterization of protein interactions: a personal perspective

This article reviews the progress of a personal endeavour to develop chromatography as a quantitative procedure for the determination of reaction stoichiometries and equilibrium constants governing protein interactions. As well as affording insight into an aspect of chromatography with which many protein chemists are unfamiliar, it shows the way in which minor adaptations of conventional chromatographic practices have rendered the technique one of the most powerful methods available for the characterization of interactions. That pathway towards quantification is followed from the introduction of frontal gel filtration for the study of protein self-association to the characterization of ligand binding by the biosensor variant of quantitative affinity chromatography.

Opening windows into the mind: mothers' preferences for mental state explanations and children's theory of mind

A new questionnaire, the Maternal Mental State Input Inventory (MMSII) was created to measure mothers' preferences for introducing and elaborating on mental states in conversation with their young children. In two studies, the questionnaire was given to mothers of young children, and the children's theory of mind (ToM) development was assessed with standard tasks. In both studies, the questionnaire exhibited good internal reliability, and significant correlations emerged between mothers' self-reported preferences for elaborated, explanatory talk about the mental states and children's theory of mind performance. Further, mothers' conversational preferences, as measured by the MMSII, were the best predictors of children's theory of mind development when relevant control variables were included in the analyses. These results converge with naturalistic observational research that has demonstrated links between mothers' conversational styles and their children's theory of mind. They go further in suggesting that mothers' tendencies toward elaborated, explanatory talk about a range of mental states is particularly beneficial to children's theory of mind development. (C) 2003 Elsevier Inc. All rights reserved.

Learning about life and death in early childhood

Inagaki and Hatano (2002) have argued that young children initially understand biological phenomena in terms of vitalism, a mode of construal in which life or life-force is the central causal-explanatory concept. This study investigated the development of vitalistic reasoning in young children's concepts of life, the human body and death. Sixty preschool children between the ages of 3 years, 7 months and 5 years, 11 months participated. All children were initially given structured interviews to assess their knowledge of (1) human body function and (2) death. From this sample 40 children in the Training group were taught about the human body and how it functions to maintain life. The Control group (n = 20) received no training. All 60 children were subsequently reassessed on their knowledge of human body function and death. Results from the initial interviews indicated that young children who spontaneously appealed to vitalistic concepts in reasoning about human body functioning were also more sophisticated in their understanding of death. Results from the posttraining interviews showed that children readily learned to adopt a vitalistic approach to human body functioning, and that this learning coincided with significant development in their understanding of human body function, and of death. The overall pattern of results supports the claim that the acquisition of a vitalistic causal-explanatory framework serves to structure children's concepts and facilitates learning in the domain of biology. (C) 2003 Elsevier Science (USA). All rights reserved.