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In this work, first-principle calculations at different levels of theory have been carried out to investigate a series of complexes formed between iodo-perfluorobenzene and several heteroatomic rings. Such model systems are selected to mimic halogen bonding interactions experimentally found within supramolecular architectures. In all cases, the predicted intermolecular distances are significantly shorter than the sums of van der Waals radii of I and N (O or S) atoms and the interactions appear to be highly directional. Halogen bonding energies, calculated at the MP2/lan12dz level, are substantial, ranging from −2.50 to −7.53 kcal/mol. Given the strength as well as the directionality comparable to hydrogen bonds, these synthons should be of general use in many fields of chemistry. Finally, to gain more insights into the nature of such interactions, we have used the natural bond orbital and atoms in molecules analyses on the studied systems, which show a considerable magnitude of charge transfer, significant orbital interaction, and distinct bond critical points between the two interacting atoms. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: In this work, a systematic theoretical investigation on a series of dimeric complexes formed between MH2 and HX has been carried out by employing correlated ab initio methods. It was shown that besides dihydrogen bonds, there also exists novel noncovalent X⋯H interactions between the two molecules, which have similar characteristics to traditional halogen bonds. Upon complexation, the Hend to elongate in all cases, concomitant with red-shifts of the Hing frequencies. X⋯H interaction energies, calculated at the MP2/aug-cc-pvtz level, range from −2.11 to −11.78kJ/mol; the interactions are much weaker than corresponding dihydrogen bonds. The major stabilization source of dihydrogen and halogen bonds arises from the electrostatic force, while charge-transfer force plays a minor role in the formation of the complexes. AIM analyses further confirm the presence of X⋯H interactions in the systems, and the electron density at bond critical points correlates fairly well with the interaction energy. [Copyright &y& Elsevier]

This study examined the relationship between job satisfaction and unethical pro‐organizational behaviours (UPB) by testing a moderated mediation model that focused on how employees' belongingness mediates the relationship between job satisfaction and UPB and how corporate ethical values moderate this mediated relationship. Our investigation included 369 employees from different organizations in Southeast China. The regression analysis revealed that job satisfaction positively influences UPB through belongingness. In addition, a moderated regression analysis indicated that low corporate ethical values strengthen not only the effect of belongingness on UPB but also the indirect effect of job satisfaction on UPB. These findings deepen our understanding of UPB by showing that individuals with a high level of job satisfaction are more likely to engage in UPB through belongingness when corporate ethical values are low. Finally, the theoretical and managerial implications of these results are discussed. [ABSTRACT FROM AUTHOR]

Background: The underlying molecular mechanisms of the excitatory/inhibitory (E/I) imbalance induced by sevoflurane exposure to neonates remain poorly understood. This study aimed to investigate the long-term effects of prolonged sevoflurane exposure to neonatal rats during the peak period of synaptogenesis on the changes of trans-synaptic neurexin-neuroligin interactions, synaptic ultrastructure in the hippocampus and cognition.Methods: A total of 30 rat pups at postnatal day (P) 7 was randomly divided into two groups: the control group (exposed to 30 % oxygen balanced with nitrogen) and the sevoflurane group (exposed to 2.5 % sevoflurane plus 30 % oxygen balanced with nitrogen) for 6 h. Neurocognitive behaviors were assessed with the Open field test at P23-25 and the Morris water maze test at P26-30. The expression of β-neurexin (β-NRX), N-methyl-d-aspartate receptor 2 subunit (NR2A and NR2B), neuroligin-1 (NLG-1), neuroligin-2 (NLG-2), postsynaptic density protein-95 (PSD-95), α1-subunit of the γ-aminobutyric acid A receptor (GABAAα1) and gephyrin in the hippocampus at P30 were measured by Western blot. The ultrastructure of synapses was examined under electron microscope.Results: Prolonged sevoflurane exposure at P7 resulted in cognitive deficiency in adolescence, as well as the downregulation of β-NRX, NR2A, NR2B, NLG-1, and PSD-95, and the upregulation of GABAAα1, NLG-2, and gephyrin in the hippocampal CA3 region. Sevoflurane anesthesia also increased the number of symmetric synapses in the hippocampus.Conclusions: Prolonged sevoflurane exposure during the brain development leads to cognitive deficiency and disproportion of excitatory/inhibitory synapses which may be caused by dysregulated expression of synaptic adhesion molecules of β-NRX and neuroligins. [ABSTRACT FROM AUTHOR]

Origin of dolostone remained a controversial subject, although numerous dolomitization models had been proposed to date. Because of the dolomitization's potential to be hydrocarbon reservoirs, one debatable issue was the role of dolomitization in porosity construction or destruction. Based upon case studies of dolostone reservoirs in various geological settings such as evaporative tidal flat (Ordos Basin, NW China), evaporative platform (Sichuan Basin, SW China), and burial and hydrothermal diagenesis (Tarim Basin, NW China), here we systematically discuss the origin of porosity in dolostone reservoirs. Contrary to traditional concepts, which regarded dolomitization as a significant mechanism for porosity creation, we found two dominant factors controlling reservoir development in dolostones, i.e., porosity inherited from precursor carbonates and porosity resulted from post-dolomitization dissolution. Actually, dolomitization rarely had a notable effect on porosity creation but rather in many cases destroyed pre-existing porosity such as saddle dolostone precipitation in vugs and fractures. Porosity in dolostones associated with evaporative tidal flat or evaporative platform was generally created by subaerial dissolution of evaporites and/or undolomitized components. Porosity in burial dolostones was inherited mostly from precursor carbonates, which could be enlarged due to subsequent dissolution. Intercrystalline porosity in hydrothermal dolostones was either formed during dolo- mitization or inherited from precursor carbonates, whereas dissolution-enlarged intercrystalline pores and/or vugs were usually interpreted to be the result of hydrothermal alteration. These understandings on dolostone porosity shed light on reservoir prediction. Dolostone reservoirs associated with evaporative tidal flat were laterally distributed as banded or quasi-stratified shapes in evaporite-bearing dolostones, and vertically presented as multi-interval patterns on tops of shallowing-upward cycles. Dolostone reservoirs associated with evaporative platform commonly occurred along epiplatforms or beneath evaporite beds, and vertically presented as multi-interval patterns in dolostones and/or evaporite-bearing dolostones of reef/shoal facies. Constrained by primary sedimentary facies, burial dolostone reservoirs were distributed in dolomitized, porous sediments of reef/shoal facies, and occurred vertically as multi-interval patterns in crystalline dolostones on tops of shallowing-upward cycles. Hydrothermal dolomitization was obviously controlled by conduits (e.g., faults, unconformities), along which lenticular reservoirs could develop. [ABSTRACT FROM AUTHOR]

Highlights: [•] A family of aminoalkyl-functionalized blue-, green- and red-emitting polyfluorene derivatives were synthesized. [•] The aminoalkyl-functionalized copolymers exhibited dual functions of efficient light emission and electron injection. [•] Device performances can be optimized by varying the molar ratios of the incorporated aminoalkyl side groups. [Copyright &y& Elsevier]

• MOF-derived porous Co 3 O 4 was obtained. • Simple calcination treatment was used to construct the porous structure. • Nanoporous Co 3 O 4 electrode with high specific capacitance was designed. Supercapacitors with cobalt oxide (Co 3 O 4) electrode are a kind of strong candidates for achieving high-capacity storage energy devices. However, the reported capacitances lower than the theoretical values are undesirable. In this study, a high-performance supercapacitor by using the Co 3 O 4 electrode with a porous nanostructure is enabled by the calcination treatment of metal organic framework ZIF-67. Of note, the resulting Co 3 O 4 electrodes shows high specific capacitance of 1015 F/g under a current density of 1 A/g. Additionally, it exhibits energy density of 36.6 Wh/kg at a power density of 189.5 W/kg and maintains capacitance retention of 78.2% after 5000 cycles at 8 A/g. The strategy proposed here provides a good way to synthesize nanostructured Co 3 O 4 , a candidate for constructing high-capacitance energy storage devices. [ABSTRACT FROM AUTHOR]

The balance of excitatory and inhibitory neurons in the central nervous system is critical for maintaining brain function and sevoflurane, a general anesthetic and an GABA receptor modulator, may change the balance of excitatory and inhibitory neurons in the cortex during early brain development. Herein, we investigated whether prenatal sevoflurane exposure (PSE) disturbs cortical neuronal development and brain function. Pregnant rats at the gestational day 14.5 were subjected to sevoflurane exposure at 3.0% for 3 h and their offspring were studied thereafter. We found a significant increase of parvalbumin-positive neurons, vesicular GABA transporter (VGAT) and GAD67 expression, and GABA neurotransmitter, and a significant decrease of vesicular glutamate transporter 1 (VGLUT1) expression and glutamate in the medial prefrontal cortex (mPFC) of offspring. Pyramidal neurons showed atrophy with shorter dendrites, less branches and lower spine density visualized by Golgi stain and a decrease of excitability with the increased miniature inhibitory postsynaptic current (mIPSC) frequency and amplitude, the decreased miniature excitatory postsynaptic current (mEPSC) frequency and excitation/inhibition (E/I) ratio using whole-cell recording in offspring. There was a significant increase of inhibitory synapse in the mPFC detected by electron microscopy. Furthermore, PSE animals showed hypo-excitatory phenotype including depression-like behaviors and learning deficits. Thus, our studies provide novel evidence that PSE causes the persisted imbalance of excitatory and inhibitory neurons in the mPFC, and this is very likely the mechanisms of the sevoflurane-induced brain functional abnormalities. • Prenatal sevoflurane exposure (PSE) enhanced GABAergic neurotransmission. • PSE resulted in pyramidal neuron atrophy. • PSE changed the E/I balance in the prefrontal cortex. • PSE caused depression-like behaviors and learning deficits. [ABSTRACT FROM AUTHOR]