Utrecht University

About: Utrecht University is a education organization based out in Utrecht, Utrecht, Netherlands. It is known for research contribution in the topics: Population & Poison control. The organization has 58176 authors who have published 139351 publications receiving 6214282 citations. The organization is also known as: UU & Universiteit Utrecht.

Determination of the Absolute Configuration of Optically Active Compounds by Means of X-Rays

Abstract: Determination of the Absolute Configuration of Optically Active Compounds by Means of X-Rays

Plant growth and competition at elevated CO2 : on winners, losers and functional groups.

Abstract: Contents Summary 175 Summary The effects of increased atmospheric CO 2 concentrations on vegetative growth and competitive performance were evaluated, using five meta-analyses. Paying special attention to functional groups, we analysed responses at three integration levels: carbon economy parameters, vegetative biomass of isolated plants, and growth in competition. CO 2 effects on seed biomass and plant-to-plant variability were also studied. Underlying the growth stimulation is an increased unit leaf rate (ULR), espe- cially for herbaceous dicots. This is mainly caused by an increase in the whole-plant rate of photosynthesis. The increased ULR is accompanied by a decrease in specific leaf area. The net result of these and other changes is that relative growth rate is only marginally stimulated. The biomass enhancement ratio (BER) of individually grown plants varies substantially across experiments/species, and size variability in the experimental populations is a vital factor in this. Fast-growing herbaceous C3 species respond more strongly than slow-growing C3 herbs or C4 plants. CAM species and woody plants show intermediate responses. When grown in competition, C4 species show lowest responses to elevated CO 2 at high nutrient conditions, whereas at low nutrient levels N 2 -fixing dicots respond relatively strongly. No systematic differences were found between slow- and fast-growing species. BER values obtained for isolated plants cannot be used to estimate BER of the same species grown in interspecific competition - the CO 2 response of monocultures may be a better predictor.

The construct validity of an alternative measure of burnout: Investigating the English translation of the Oldenburg Burnout Inventory

Abstract: While the most commonly employed burnout measure has been the Maslach Burnout Inventory (MBI), researchers have been troubled by some of the psychometric limitations of that scale (e.g. wording of the scale items) as well as the limited conceptualization of burnout upon which it is based. As a result, Demerouti et al. have developed an alternative measure of burnout, the Oldenburg Burnout Inventory (OLBI). The purpose of this paper is to develop evidence for the validity and reliability of an English-language translation of the OLBI. As such, this study is among the first validation studies of the OLBI, and the first to assess the characteristics of the OLBI an English-speaking sample. Using data from 2599 employees across two samples from the United States (a generalized sample of working adults and a sample of fire department employees), our preliminary multi-trait, multi-method (MTMM) and confirmatory factor analyses suggested that the OLBI may be a viable alternative to the Maslach Burnout In...

Protein Folding and Modification in the Mammalian Endoplasmic Reticulum

Abstract: Analysis of the human genome reveals that approximately a third of all open reading frames code for proteins that enter the endoplasmic reticulum (ER), demonstrating the importance of this organelle for global protein maturation. The path taken by a polypeptide through the secretory pathway starts with its translocation across or into the ER membrane. It then must fold and be modified correctly in the ER before being transported via the Golgi apparatus to the cell surface or another destination. Being physically segregated from the cytosol means that the ER lumen has a distinct folding environment. It contains much of the machinery for fulfilling the task of protein production, including complex pathways for folding, assembly, modification, quality control, and recycling. Importantly, the compartmentalization means that several modifications that do not occur in the cytosol, such as glycosylation and extensive disulfide bond formation, can occur to secreted proteins to enhance their stability before their exposure to the extracellular milieu. How these various machineries interact during the normal pathway of folding and protein secretion is the subject of this review.