Physical health problems, depressive mood, and cortisol secretion in old age: Buffer effects of health engagement control strategies.

Objective: This study examined the protective role played by control behaviors aimed at overcoming physical health problems (health engagement control strategies; HECS) in the associations between older adults' physical health problems, depressive mood, and diurnal cortisol secretion. It was expected that adaptive levels of HECS would buffer the adverse effects of physical health problems on depressive mood and diurnal cortisol secretion. Design and Measures: Physical health problems and HECS were measured in a cross-sectional sample of 215 community-dwelling older adults. In addition, participants' depressive mood and patterns of diurnal cortisol secretion were assessed across 3 days. Results: The findings demonstrate that physical health problems predicted high levels of depressive mood and diurnal cortisol secretion, but only among older adults who reported low levels of HECS (and not among older adults who reported high levels of HECS). Moreover, depressive mood completely mediated the buffering effect of HECS on the association between physical health problems and cortisol secretion. Conclusion: The results suggest that adaptive levels of HECS represent a psychological mechanism that can protect older adults from experiencing the adverse emotional and biological consequences of physical health problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral and developmental consequences of early rearing experience for captive giant pandas (Ailuropoda melanoleuca).

Mother-reared (MR) and peer-reared (PR) captive giant panda (Ailuropoda melanoleuca) cubs were compared to evaluate the effects of early removal from mother on behavioral development. Males and females and twins and singletons were compared to assess the effects of social setting on behavioral development. Subjects included 2 PR females, 3 MR females, 3 MR males, and 3 mothers. MR cubs spent more time manipulating bamboo and fell more often than PR cubs. PR cubs spent more time inactive. Male cubs directed more playful behavior at their mothers. Twins spent more time play fighting with their mothers than with their siblings. The results suggest that peer-rearing does not provide young pandas with the same level of social stimulation as mother-rearing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rapid Determination of the Amino Acid Configuration of Xenotetrapeptide

An E. coli strain with deletions in five transaminases (ΔaspC ΔilvE ΔtyrB ΔavtA ΔybfQ) was constructed to be unable to degrade several amino acids. This strain was used as an expression host for the analysis of the amino acid configuration of nonribosomally synthesized peptides, including the novel peptide “xenotetrapeptide” from Xenorhabdus nematophila, by using a combination of labeling experiments and mass spectrometry. Additionally, the number of D ‐amino acids in the produced peptide was assigned following simple cultivation of the expression strain in D₂O.     

Synthesis and optical properties of luminescent core-shell structured silicate and phosphate nanoparticles

Monodisperse, luminescent core-shell structured inorganic nanoparticles were synthesized by sol-gel technology. They exhibit an amorphous SiO₂ core and a crystalline luminescent shell. Zn₂SiO₄:Mn²⁺ and Ca₁₀(PO₄)₆OH:Eu³⁺ shell materials are investigated. The influence of the doping concentration on optical and structural properties was studied. The resulting nanoparticles were characterized by X-ray diffraction analysis, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, and photoluminescence spectroscopy.     

Monolithic ZnTe-based pillar microcavities containing CdTe quantum dots

Micropillars of different diameters have been prepared by focused ion beam milling out of a planar ZnTe-based cavity. The monolithic epitaxial structure, deposited on a GaAs substrate, contains CdTe quantum dots embedded in a ZnTe λ-cavity delimited by two distributed Bragg reflectors (DBRs). The high refractive index material of the DBR structure is ZnTe, while for the low index material a short-period triple MgTe/ZnTe/MgSe superlattice is used. The CdTe quantum dots are formed by a novel Zn-induced formation process and are investigated by scanning transmission electron microscopy. Micro-photoluminescence measurements show discrete optical modes for the pillars, in good agreement with calculations based on a vectorial transfer matrix method. The measured quality factor reaches a value of 3100.     

4‐Cyanoresorcinol‐Based Bent‐Core Mesogens with Azobenzene Wings: Emergence of Sterically Stabilized Polar Order in Liquid Crystalline Phases

A new series of azobenzene containing bent‐core molecules incorporating 4‐cyanoresorcinol as the central core unit exhibiting cybotactic nematic, rectangular, columnar, and different types of tilted smectic (SmC) phases are synthesized. The mesophase behavior and phase structures are characterized in bulk and freely suspended films using a variety of experimental techniques. Depending on the chain length and temperature a series of different mesophases is observed in these compounds, ranging from cybotactic nematic via paraelectric SmC phases, polarization randomized SmC_sP_R phases to ferroelectric and antiferroelectric SmC phases, associated with increasing size and correlation length of the polar domains. Spontaneous formation of chiral domains is observed in the paraelectric SmC and the SmC_sP_R phases and discussed in relation with superstructural chirality, bend elastic constants, and surface effects.