Irritation at school: Reasons to initiate strain management earlier.

Organizational research provides many tested stressor–strain relationships in the workforce. To a lesser extent, it has been researched whether strain may already be present before the commencement of employment. The final years of school may be experienced as straining, because the need to perform well to obtain further education and, therefore, job opportunities, is often intense. To explore this, a scale measuring irritation, a well-documented concept of psychological strain at work, was adapted to the situation of school adolescents. Samples from 2 Swiss schools (n = 1,310 and n = 301) were obtained to study (a) the reliability of the adapted irritation scale, (b) the relationships between school stressors and irritation, (c) the moderating influences of self-efficacy on the relationship between stressors and irritation, and (d) the mediating effect of irritation in the relationship between stressors and other psychological impairments. These hypotheses were in line with results from organizational stress research. Results indicate the same mechanisms at play as those found in occupational stress research studies and implications with regard to stress interventions at school are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auf dem Weg zu einer „Gefälligkeitsmedizin“?!

Ohne Zusammenfassung     

Energy sector reform,energy transitions and the poor in Africa

There is little systematic information about the impact of energy sector reform on all sources and methods of energy utilised or potentially utilised by the poor. It is not sufficiently known what fuels the poor use, if a larger range of fuels becomes available and affordable and if barriers to access and consumption are reduced. A detailed assessment is presented for four countries, three in Africa (Botswana, Ghana and Senegal) and for comparison one in Latin America (Honduras), of steps taken to reform the energy sector and their effect on various groups of poor households. The paper analyses the pattern of energy supply to, and use by, poor households and explores the link—or its absence—to energy policy. We investigate what works for the poor and which type of reforms and implementation are effective and lead to a transition to more efficient and clean fuels from which the poor benefit.     

Stabilization of the Furuta Pendulum with backlash using H∞‐LMI technique: experimental validation

The rotary inverted pendulum, also named Furuta Pendulum, has been studied extensively for control performance evaluation in under‐actuated mechanisms. The H_∞ control invoking linear matrix inequality (H_∞‐LMI) has been also widely employed for linear control design. This paper deals with the feasibility of the H_∞‐LMI technique to stabilize the rotary inverted pendulum around its unstable equilibrium point when there exists a backlash nonlinearity in the actuator. So, the H_∞‐LMI faces the nonlinear effect in the actuator and the non‐linear pendulum model. Experimental realization of the designed H_∞‐LMI control also shows evidence of the good performance of the controller subject to external perturbation. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society     

Prostaglandine und Prostaglandinvorstufen. Untersuchungen zur Synthese von 8-Methylprostansäurederivaten

Prostaglandins and Prostaglandin Intermediates. Synthetic Approach to 8-Methyl Prostanoic Acid Derivatives Starting from the chiral key-product 1 the 8-methyl prostanoic acid derivative 13 was prepared within 10 steps. Construction of the α-side chain involves DIBAH-reduction of the lacton moiety of 1 followed by Wittig-olefination with a C₅-ylide. C₁-Homologation of the oxo group of 1 via cyanhydrin synthesis and Wittig-olefination with a C₇-ylide are important steps to form the ß-side chain of compound 13 .     

Synthesis and Evaluation of a Chitosan–Silica-Based Bone Substitute for Tissue Engineering

Bone defects have prompted the development of biomaterial-based bone substitutes for restoring the affected tissue completely. Although many biomaterials have been designed and evaluated, the combination of properties required in a biomaterial for bone tissue engineering still poses a challenge. In this study, a chitosan–silica-based biocomposite was synthetized, and its physicochemical characteristics and biocompatibility were characterized, with the aim of exploring the advantages and drawbacks of its use in bone tissue engineering. Dynamic light scattering measurements showed that the mean hydrodynamic size of solid silica particles (Sol-Si) was 482 ± 3 nm. Scanning electron microscopy of the biocomposite showed that Sol-Si were homogenously distributed within the chitosan (CS) matrix. The biocomposite swelled rapidly and was observed to have no cytotoxic effect on the [3T3] cell line within 24 h. Biocompatibility was also analyzed in vivo 14 days post-implant using a murine experimental model (Wistar rats). The biocomposite was implanted in the medullary compartment of both tibiae (n = 12). Histologically, no acute inflammatory infiltrate or multinucleated giant cells associated to the biocomposite were observed, indicating good biocompatibility. At the tissue–biocomposite interface, there was new formation of woven bone tissue in close contact with the biocomposite surface (osseointegration). The new bone formation may be attributed to the action of silica. Free silica particles originating from the biocomposite were observed at the tissue–biocomposite interface. According to our results, the biocomposite may act as a template for cellular interactions and extracellular matrix formation, providing a structural support for new bone tissue formation. The CS/Sol-Si biocomposite may act as a Si reservoir, promoting new bone formation. A scaffold with these properties is essential for cell differentiation and filling a bone defect.     

The relationship between selected cognitive abilities and learning: A second look.

Examined the relationship between learning strategies and cognitive abilities in 3 experiments using a total of 420 3rd-12th graders from rural school as Ss. Ability tests given to Ss included Raven's Progressive Matrices and a digit span test. Based on the argument that such relationships ought to follow predictable and differentiated patterns, different strategy manipulations were used in an attempt to moderate the relationship between reasoning and memory abilities and free recall and paired associate learning. Results suggest that meaningful differential interrelations can be demonstrated as long as the processes and strategies forming the link between learning and ability test performance are both potent and well understood. Implications for future research into the cross-linkages between intelligence and learning tasks are discussed. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Receptor‐Mediated Uptake of Boron‐Rich Neuropeptide Y Analogues for Boron Neutron Capture Therapy

Peptidic ligands selectively targeting distinct G protein‐coupled receptors that are highly expressed in tumor tissue represent a promising approach in drug delivery. Receptor‐preferring analogues of neuropeptide Y (NPY) bind and activate the human Y₁ receptor subtype (hY₁ receptor), which is found in 90 % of breast cancer tissue and in all breast‐cancer‐derived metastases. Herein, novel highly boron‐loaded Y₁‐receptor‐preferring peptide analogues are described as smart shuttle systems for carbaboranes as ¹⁰B‐containing moieties. Various positions in the peptide were screened for their susceptibility to carbaborane modification, and the most promising positions were chosen to create a multi‐carbaborane peptide containing 30 boron atoms per peptide with excellent activation and internalization patterns at the hY₁ receptor. Boron uptake studies by inductively coupled plasma mass spectrometry revealed successful uptake of the multi‐carbaborane peptide into hY₁‐receptor‐expressing cells, exceeding the required amount of 10⁹ boron atoms per cell. This result demonstrates that the NPY/hY receptor system can act as an effective transport system for boron‐containing moieties.