The polarization of Lyman alpha radiation produced in charge transfer collisions between protons and the inert gases

Polarization of Lyman alpha radiation in proton collisions with helium, argon, and neon atom

The polarization of Lyman alpha radiation produced by direct excitation of hydrogen atoms by proton impact

Lyman alpha radiation measurement in collision between protons and hydrogen atom

A Self-Consistent Model for Positronium Formation from Helium Atoms

The differential and total cross sections for electron capture by positrons from helium atoms are calculated using a first-order distorted wave theory satisfying the Coulomb boundary conditions. In this formalism a parametric potential is used to describe the electron screening in a consistent and realistic manner. The present procedure is self consistent because (i) it satisfies the correct boundary conditions and post-prior symmetry, and (ii) the potential and the electron binding energies appearing in the transition amplitude are consistent with the wave functions describing the collision system. The results are compared with the other theories and with the available experimental measurements. At the considered range of collision energies, the results agree reasonably well with recent experiments and theories. [Note: This paper will be published on volume 42 of the Brazilian Journal of Physics

Leader-member exchange (LMX) differentiation and work outcomes:conceptual clarification and critical review

According to Leader-member Exchange (LMX) theory, leaders develop different quality relationships with followers in their team (termed LMX differentiation). An important theoretical question concerns how different LMX relationships within a team affect followers’ work outcomes. This paper provides a critical review of the concept of LMX differentiation. We propose that the LMX differentiation process leads to patterns of LMX relationships that can be captured by three properties (central tendency, variation, and relative position). We describe a taxonomy illustrating the different ways these properties have been conceptualized and measured. We identify two approaches to LMX differentiation as being a ‘perspective of the team’ (that are shared amongst team members) or a ‘perspective of the follower’ (subjective perceptions unique to each follower). These perspectives lead to different types of measures that predict different outcomes at the individual and team levels. We describe theoretical models employed to explain the effects of LMX differentiation (justice, social comparison and social identity theories). Generally, the lower the within-team variation in LMX or the more a team member’s LMX is higher than the mean team LMX, the better are the work outcomes, but many moderators condition these effects. Finally, we identify some key areas for future research

Study protocol: a double blind placebo controlled trial examining the effect of domperidone on the composition of breast milk [NCT00308334]

BACKGROUND: Domperidone, a drug that enhances upper gastric motility, is an anti-dopaminergic medication that also elevates prolactin levels. It has been shown to safely increase the milk supply of lactating women. To date, researchers have analyzed the effects of domperidone on lactating woman with respect to the quantity of their milk production, adverse effects, and drug levels in the breast milk. However, the effect of domperidone on the macronutrient composition of breast milk has not been studied and current guidelines for fortification of human milk for premature infants do not distinguish between those women using or those not using domperidone. The purpose of this study is to evaluate the effect of domperidone (given to lactating mothers of very preterm infants) on the macronutrient composition of breast milk. METHODS/DESIGN: Mothers of infants delivered at less than 31 weeks gestation, who are at least 3 weeks postpartum, and experiencing lactational failure despite non-pharmacological interventions, will be randomized to receive domperidone (10 mg three times daily) or placebo for a 14-day period. Breast milk samples will be obtained the day prior to beginning treatment and on days 4, 7 and 14. The macronutrient (protein, fat, carbohydrate and energy) and macromineral content (calcium, phosphorus and sodium) will be analyzed and compared between the two groups. Additional outcome measures will include milk volumes, serum prolactin levels (measured on days 0, 4, and 10), daily infant weights and breastfeeding rates at 2 weeks post study completion and at discharge. Forty-four participants will be recruited into the study. Analysis will be carried out using the intention to treat approach. DISCUSSION: If domperidone causes significant changes to the nutrient content of breast milk, an alteration in feeding practices for preterm infants may need to be made in order to optimize growth, nutrition and neurodevelopment outcomes

The interplay of matrix metalloproteinase-8, transforming growth factor-beta 1 and vascular endothelial growth factor-C cooperatively contributes to the aggressiveness of oral tongue squamous cell carcinoma

Background: Matrix metalloproteinase-8 (MMP-8) has oncosuppressive properties in various cancers. We attempted to assess MMP-8 function in oral tongue squamous cell carcinoma (OTSCC). Methods: MMP-8 overexpressing OTSCC cells were used to study the effect of MMP-8 on proliferation, apoptosis, migration, invasion and gene and protein expression. Moreover, MMP-8 functions were assessed in the orthotopic mouse tongue cancer model and by immunohistochemistry in patient samples. Results: MMP-8 reduced the invasion and migration of OTSCC cells and decreased the expression of MMP-1, cathepsin-K and vascular endothelial growth factor-C (VEGF-C). VEGF-C was induced by transforming growth factor-beta 1 (TGF-beta 1) in control cells, but not in MMP-8 overexpressing cells. In human OTSCC samples, low MMP-8 in combination with high VEGF-C was an independent predictor of poor cancer-specific survival. TGF-beta 1 treatment also restored the migration of MMP-8 overexpressing cells to the level of control cells. In mouse tongue cancer, MMP-8 did not inhibit metastasis, possibly because it was eliminated in the peripheral carcinoma cells. Conclusions: The suppressive effects of MMP-8 in OTSCC may be mediated through interference of TGF-beta 1 and VEGF-C function and altered proteinase expression. Together, low MMP-8 and high VEGF-C expression have strong independent prognostic value in OTSCC.Peer reviewe

Forestry for a low carbon future. Integrating forests and wood products in climate change strategies

Following the introduction, Chapter 2 provides an overview of mitigation in the forest sector, addressing the handling of forests under UNFCCC. Chapters 3 to 5 focus on forest-based mitigation options – afforestation, reforestation, REDD+ and forest management – and Chapters 6 and 7 focus on wood-product based options – wood energy and green building and furnishing. The publication describes these activities in the context of UNFCCC rules, assessing their mitigation potential and economic attrac tiveness as well as opportunities and challenges for implementation. Chapter 8 discusses the different considerations involved in choosing the right mix of options as well as some of the instruments and means for implementation. Chapter 8 also highlights the co-benefits generated by forest-based mitigation and emphasizes that economic assessment of mitigation options needs to take these benefits into account. The concluding chapter assesses national commitments under UNFCCC involving forest miti gation and summarizes the challenges and opportunities

How many is enough? Determining optimal count totals for ecological and palaeoecological studies of testate amoebae

Testate amoebae are increasingly used in ecological and palaeoecological studies of wetlands. To characterise the amoeba community a certain number of individuals need to be counted under the microscope. To date, most studies have aimed for 150 individuals, but that sample size is not based on adequate evidence. When testate amoeba concentrations are low, it can be difficult or impossible to reach this total. The impacts of lower count totals have never been seriously scrutinised. We investigated the impact of count size on number of taxa identified, quantitative inferences of environmental variables and the strength of the links between amoebae and environmental data in the context of predicting depth to water table. Low counts were simulated by random selection of individuals from four existing datasets. Results show progressively diminishing returns by all criteria as count size increases from low numbers to counts of 150. A higher count is required to identify all taxa than to adequately characterise the community for transfer function inference. We suggest that in most cases, it will be a more efficient use of time to count a greater number of samples to a lower count. While a count of 50 individuals may be sufficient for some samples from some sites we recommend that counts of 100 individuals should be sufficient for most samples. Counts need only be increased to 150 or more where the aim is to identify relatively minor, but still potentially ecologically relevant community changes. This approach will help reduce lack of replication and low resolution, which are common limitations in testate amoeba-based palaeoecological and ecological studies

Behavior in behavioral strategy : capturing, measuring, analyzing

Measuring behavior requires research methods that can capture observed outcomes and expose underlying processes and mechanisms. In this chapter, we present a toolbox of instruments and techniques we designed experimental tasks to simulate decision environments and capture behavior. We deployed protocol analysis and text analysis to examine the underlying cognitive processes. In combination, these can simultaneously grasp antecedents, outcomes, processes, and mechanisms. We applied them to collect rich behavioral data on two key topics in strategic management: the exploration–exploitation trade-off and strategic risk-taking. This mix of methods is particularly useful in describing actual behavior as it is, not as it should be, replacing assumptions with data and offering a finer-grained perspective of strategic decision-making