bluuebunny/crossref_metadata_2025_split huggingface dataset:
Individual variation in body burden, lipid status, and reproductive investment is related to maternal transfer of a brominated diphenyl ether (BDE-99) to eggs in the zebra finch
Authors: Eng Margaret L. , Elliott John E. , Letcher Robert J. , Williams Tony D. 
Published: October 2012

Abstract
Avian eggs are exposed to hydrophobic contaminants through maternal transfer. How maternal transfer of contaminants within a species is influenced by individual variation in characteristics such as body burden, yolk precursor levels, or reproductive investment is not understood. The authors investigated sources of variation in the maternal transfer of 2,2′,4,4′,5-pentabromodiphenyl ether (BDE-99) in zebra finches (Taeniopygia guttata). The authors dosed adult female zebra finches with levels of BDE-99 relevant to exposure in wild birds (0, 33.7 or 173.8 ng/g body wt/d) for three weeks prior to pairing. Maternal BDE-99 and very-low-density lipoprotein (VLDL) in plasma were measured during egg formation and at clutch completion, and BDE-99 was measured in the corresponding egg. The lipid-normalized egg-to-maternal tissue BDE-99 relationship decreased with increasing maternal burden. Individual variation in maternal VLDL was related to BDE-99 transfer to the eggs when BDE-99 was at background levels in control birds, but not when BDE-99 was elevated in dosed birds. The decrease in maternal plasma BDE-99 over the laying period was only significant (p &lt; 0.05) in the high-dose birds. Finally, the decrease in BDE-99 in maternal plasma during egg-laying was significantly positively correlated with clutch mass in the high-dose group. These results suggest that the relationship between maternal and egg contaminant levels can be highly variable. This has significant implications for using eggs as indicators of adult or environmental concentrations. Environ. Toxicol. Chem. 2013;32:345–352. © 2012 SETAC
Wireless MIMO switching: network‐coded MMSE relaying and user group selection
Authors: Wang Fanggang 
Published: October 2012

ABSTRACTA wireless relay that forms a one‐to‐one mapping from the inputs (uplinks) to the outputs (downlinks) is called a multiple‐input multiple‐output (MIMO) switch. The MIMO switch carries outprecode‐and‐forward, where all users send their signals in the uplink, and then, the MIMO switch precodes the received vector signal for broadcasting in the downlink. Ideally, each user employs a receive filter to recover its desired signal from one other user with no or little interference from other users. We first propose a joint design of the precoder and the receive filters to achieve the minimum‐mean‐ square‐error (MMSE), where network coding technique is incorporated, assuming that full channel state information is available at the relay. When the number of relay antennas is smaller than the number of source users, that is, the users that need to transmit signals, we investigate user group selection algorithms for the proposed MMSE relaying schemes. Our results indicate that the proposed MMSE relaying scheme outperforms the existing zero‐forcing/MMSE schemes. In addition, the results validate the efficiency of the proposed user group selection algorithms. Copyright © 2012 John Wiley & Sons, Ltd.
Recent Progress in the Synthesis and Structural Clarification of Thermotropic Cubic Phases
Authors: Kutsumizu Shoichi 
Published: October 2012

AbstractThis review article focuses on recent advances and challenges in the field of thermotropic cubic phases of the bicontinuous type (Cubbi) formed by low molecular mass molecules. In the Cubbi phases, the constituent molecules self‐organize into 3D network structures, although local molecular diffusional motions are preserved to some extent. This review illustrates which types of molecules form such structures, and summarizes the latest developments in structural characterization. Moreover, their phase behaviors, and analogies and differences in comparison with other related systems such as lyotropic liquid crystals and block copolymers are discussed. Finally, potential applications utilizing the dynamically ordered 3D network structures are presented.
Stress effect on bone remodeling and osseointegration on dental implant with novel nano/microporous surface functionalization
Authors: Cheng Han‐Yi , Chu Kuo‐Tien , Shen Fa‐Chih , Pan Yung‐Ning , Chou Hsin‐Hua , Ou Keng‐Liang 
Published: October 2012

AbstractThe objective of this study was to investigate the stress distributions of a surface‐treated dental implant and bone tissue under physiological loading. For ensuring success of dental implant treatment, one must examine the magnitude and location of the maximum stresses. Stress analysis models were constructed from computer tomography data. Although several studies have investigated finite element models of dental implants, none have used an implant model with a nanoporous layer in a biomimetic geometrical mandible model. The novel implant surface used in this study, comprised of a microlevel porous containing a nanolevel porous structure, was complex and it was difficult to present due to the limitation of computer efficiency. However, this complex geometry was simplified using a film, to further investigate stresses resulting from 0 nm, 50 nm, 500 nm, 5 μm, and 50 μm surface treatment thicknesses. Results indicated that the stresses transferred more uniformly in implants with nanoporous surface treatments, and that the stresses decreased with increasing layer thickness. Our study showed that this could be potentially beneficial for understanding the stress properties of surface‐treated layers for dental implants. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Bone tissue engineering of induced pluripotent stem cells cultured with macrochanneled polymer scaffold
Authors: Jin Guang‐Zhen , Kim Tae‐Hyun , Kim Joong‐Hyun , Won Jong‐Eun , Yoo So‐Young , Choi Seong‐Jun , Hyun Jung Keun , Kim Hae‐Won 
Published: October 2012

AbstractA reliable source of osteogenic cells is an essential factor for bone tissue engineering. In this study, human‐induced pluripotent stem cells (hiPSCs) without an embryoid body step were cultured in macrochanneled poly(caprolactone) (PCL) scaffolds prepared using a robotic dispensing technique, after which osteogenesis was promoted by the addition of exogenous osteogenic factors. The osteogenesis of the hiPSCs was demonstrated based on the detection of osteogenic molecules, such as osteopontin, using flow cytometry analysis, quantitative polymerase chain reaction and western blotting. Thereafter, the cell‐scaffold constructs were transplanted into the subcutaneous site of male athymic mice. At 4 weeks after implantation, histological assays (hematoxylin & eosin staining, Alizarin red staining, and osteocalcin immunostaining) were conducted to determine the bone induction of hiPSCs. The results indicated a production of pronounced levels of extracellular matrices and their mineral deposition within the cell‐scaffold implant, suggesting possible in vivo bone induction by the hiPSCs‐based tissue engineering approach. The results presented here provide useful information regarding the tissue engineering of bone utilizing hiPSCs in conjunction with cell‐supporting scaffolds. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Comparative studies of polyethylenimine–doxorubicin conjugates with pH‐sensitive and pH‐insensitive linkers
Authors: Dong Da‐Wen , Tong Shu‐Wen , Qi Xian‐Rong 
Published: October 2012

AbstractDoxorubicin (DOX) was conjugated to polyethylenimine (PEI) in several synthetic ways and created PEI–succinic anhydride (SUC)–DOX, PEI–N‐succinimidyl 3‐maleimidopropionate (SMP)–DOX and PEI–3‐maleimidopropionic acid hydrazide (MPH)–DOX conjugates using pH‐insensitive linkage (amide bond) or pH‐sensitive linkage (hydrazone bond). The effects of the conjugates on anticancer therapy against human breast cancer cells were investigated for in vitro release under different pH, cellular uptake, intracellular localization and antiproliferative activity. DOX release from PEI–MPH–DOX formed via hydrazone bonds occurred in an acid‐triggered manner and increased with decreasing pH. But PEI–SUC–DOX and PEI–SMP–DOX formed via amide bonds were quite stable and released negligible DOX under both neutral and acidic conditions. The results from flow cytometry and confocal laser scanning microscopy analysis showed that conjugates uptakes were PEI–SUC–DOX > PEI–SMP–DOX > PEI–MPH–DOX, which was consistent with the primary amine content and more efficient than free DOX due to the intense nonspecific interaction between the positively charged conjugates and the negatively charged cell surface proteoglycans. PEI–MPH–DOX showed higher antiproliferative activity than that of PEI–SUC–DOX and PEI–SMP–DOX. The antiproliferative activity of PEI–MPH–DOX was achieved through the endocytosis, nuclear entry of released DOX and interaction with the DNA. However, PEI–SUC–DOX and PEI–SMP–DOX showed more endocytosis but less nuclear entry leading to lower antiproliferative activity. According to the measurements, we determined that enhanced endocytosis and pH‐sensitive drug release were the critical processes in determining anticancer therapy of drug–polymer conjugate. The PEI–MPH–DOX conjugate could be sifted to use as a prodrug for cancer therapy and also as a novel delivery carrier to codelivery DOX and gene in further research. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
In vitro cytotoxicity and in vivo osseointergration properties of compression‐molded HDPE‐HA‐Al2O3 hybrid biocomposites
Authors: Tripathi Garima , Gough Julie E. , Dinda Amit , Basu Bikramjit 
Published: October 2012

AbstractThe aim of this study was to investigate the in vivo biocompatibility in terms of healing of long segmental bone defect in rabbit model as well as in vitro cytotoxicity of eluates of compression‐molded High density polyethylene (HDPE)–hydroxyapatite (HA)‐aluminum oxide (Al2O3) composite‐based implant material. Based on the physical property in terms of modulus and strength properties, as reported in our recent publication, HDPE‐40 wt % HA and HDPE‐20 wt % HA‐20 wt % Al2O3 hybrid composites were used for biocompatibility assessment. Osteoblasts cells were cultured in conditioned media, which contains varying amount of composite eluate (0.01, 0.1, and 1.0 wt %). In vitro, the eluates did not exhibit any significant negative impact on proliferation, mineralization or on morphology of human osteoblast cells. In vivo, the histological assessment revealed neobone formation at the bone/implant interface, characterized by the presence of osteoid and osteoblasts. The observation of osteoclastic activity indicates the process of bone remodeling. No inflammation to any noticeable extent was observed at the implantation site. Overall, the combination of in vitro and in vivo results are suggestive of potential biomedical application of compression‐molded HDPE‐ 20 wt % HA‐ 20 wt % Al2O3 composites to heal long segmental bone defects without causing any toxicity of bone cells. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
How water molecules modulate the hydration of CO2 in water solution: Insight from the cluster‐continuum model calculations
Authors: Wang Binju , Cao Zexing 
Published: October 2012

AbstractThe hydration of CO2 in water solution was investigated by the cluster‐continuum model calculations with n = 1–8 water molecules. For n = 1–4 water molecules, all the reactions follow a concerted pathway to the hydration product directly. For n = 5–8 water molecules, all the reactions follow a stepwise mechanism and a labile H3O+ intermediate is involved in reaction. The surrounding water molecules from the bulk solvent play a key role in the proton relay process, which can stabilize the charged transition state and the H3O+ intermediate in reaction. Furthermore, if the proton transfer from H3O+ to the carbonyl oxygen occurs, the hydration pathway will be followed. If there is a proton transfer from H3O+ to the outer water phase through the water bridge, the dissociation product of HCO3− will be formed. The predicted reaction energetics by current cluster‐continuum model calculations shows good agreement with the experimental values. Present calculations strongly suggest the suitable cluster‐continuum model including more explicit water molecules highly required for reasonable and unbiased description of the proton relay mechanism for proton transfer related reactions in water solution. © 2012 Wiley Periodicals, Inc.
Natural bond orbital analysis in the ONETEP code: Applications to large protein systems
Authors: Lee Louis P. , Cole Daniel J. , Payne Mike C. , Skylaris Chris‐Kriton 
Published: October 2012

AbstractFirst principles electronic structure calculations are typically performed in terms of molecular orbitals (or bands), providing a straightforward theoretical avenue for approximations of increasing sophistication, but do not usually provide any qualitative chemical information about the system. We can derive such information via post‐processing using natural bond orbital (NBO) analysis, which produces a chemical picture of bonding in terms of localized Lewis‐type bond and lone pair orbitals that we can use to understand molecular structure and interactions. We present NBO analysis of large‐scale calculations with the ONETEP linear‐scaling density functional theory package, which we have interfaced with the NBO 5 analysis program. In ONETEP calculations involving thousands of atoms, one is typically interested in particular regions of a nanosystem whilst accounting for long‐range electronic effects from the entire system. We show that by transforming the Non‐orthogonal Generalized Wannier Functions of ONETEP to natural atomic orbitals, NBO analysis can be performed within a localized region in such a way that ensures the results are identical to an analysis on the full system. We demonstrate the capabilities of this approach by performing illustrative studies of large proteins—namely, investigating changes in charge transfer between the heme group of myoglobin and its ligands with increasing system size and between a protein and its explicit solvent, estimating the contribution of electronic delocalization to the stabilization of hydrogen bonds in the binding pocket of a drug‐receptor complex, and observing, in situ, the n → π* hyperconjugative interactions between carbonyl groups that stabilize protein backbones. © 2012 Wiley Periodicals, Inc.
GRID: A high‐resolution protein structure refinement algorithm
Authors: Chitsaz Mohsen , Mayo Stephen L. 
Published: October 2012

AbstractThe energy‐based refinement of protein structures generated by fold prediction algorithms to atomic‐level accuracy remains a major challenge in structural biology. Energy‐based refinement is mainly dependent on two components: (1) sufficiently accurate force fields, and (2) efficient conformational space search algorithms. Focusing on the latter, we developed a high‐resolution refinement algorithm called GRID. It takes a three‐dimensional protein structure as input and, using an all‐atom force field, attempts to improve the energy of the structure by systematically perturbing backbone dihedrals and side‐chain rotamer conformations. We compare GRID to Backrub, a stochastic algorithm that has been shown to predict a significant fraction of the conformational changes that occur with point mutations. We applied GRID and Backrub to 10 high‐resolution (≤ 2.8 Å) crystal structures from the Protein Data Bank and measured the energy improvements obtained and the computation times required to achieve them. GRID resulted in energy improvements that were significantly better than those attained by Backrub while expending about the same amount of computational resources. GRID resulted in relaxed structures that had slightly higher backbone RMSDs compared to Backrub relative to the starting crystal structures. The average RMSD was 0.25 ± 0.02 Å for GRID versus 0.14 ± 0.04 Å for Backrub. These relatively minor deviations indicate that both algorithms generate structures that retain their original topologies, as expected given the nature of the algorithms. © 2012 Wiley Periodicals, Inc.
Structure and spectroscopic aspects of water‐halide ion clusters: A study based on a conjunction of stochastic and quantum chemical methods
Authors: Neogi Soumya Ganguly , Chaudhury Pinaki 
Published: October 2012

AbstractIn this article, we propose a stochastic search based method, namely genetic algorithm in conjunction with density functional theory to evaluate structures of water‐halide microclusters, with the halide ion being Cl−, Br−, and I−. Once the structures are established, we evaluate the infrared spectroscopic modes, vertical detachment energies and natural population analysis based charges. We compare our results with available experimental and theoretical results. © 2012 Wiley Periodicals, Inc.
A Pilot Study and Randomized Controlled Trial of the Mindful Self‐Compassion Program
Authors: Neff Kristin D. , Germer Christopher K. 
Published: October 2012

ObjectivesThe aim of these two studies was to evaluate the effectiveness of the Mindful Self‐Compassion (MSC) program, an 8‐week workshop designed to train people to be more self‐compassionate.MethodsStudy 1 was a pilot study that examined change scores in self‐compassion, mindfulness, and various wellbeing outcomes among community adults (N = 21; mean [M] age = 51.26, 95% female). Study 2 was a randomized controlled trial that compared a treatment group (N = 25; M age = 51.21; 78% female) with a waitlist control group (N = 27; M age = 49.11; 82% female).ResultsStudy 1 found significant pre/post gains in self‐compassion, mindfulness, and various wellbeing outcomes. Study 2 found that compared with the control group, intervention participants reported significantly larger increases in self‐compassion, mindfulness, and wellbeing. Gains were maintained at 6‐month and 1‐year follow‐ups.ConclusionsThe MSC program appears to be effective at enhancing self‐compassion, mindfulness, and wellbeing.
Combat Exposure and Suicide Risk in Two Samples of Military Personnel
Authors: Bryan Craig J. , Hernandez Ann Marie , Allison Sybil , Clemans Tracy 
Published: October 2012

ObjectiveIn light of increased suicidal behaviors among military personnel and veterans since the initiation of combat operations in Afghanistan and Iraq, questions have been raised about the potential causal role of combat. The objective of the current study was to identify any direct or indirect effects of combat exposure on suicide risk through depression symptom severity, posttraumatic stress disorder (PTSD) symptom severity, thwarted belongingness, perceived burdensomeness, and fearlessness about death, consistent with the interpersonal‐psychological theory of suicide (Joiner, 2005).MethodStructural equation modeling was utilized with two separate samples of deployed military personnel, 1 nonclinical (n = 348; 89.7% male, mean age = 24.50) and 1 clinical (n = 219; 91.8% male, mean age = 27.88), to test the effects of combat exposure on suicide risk.ResultsGreater combat exposure was directly associated with fearlessness about death and PTSD symptom severity in both samples, but failed to show either a direct or indirect effect on suicide risk. PTSD symptom severity was strongly associated with depression symptom severity, which in turn was related to suicide risk directly (in the nonclinical sample) or indirectly through low belongingness and perceived burdensomeness (in the clinical sample).ConclusionsIn both samples of deployed active duty military personnel, combat exposure was either unrelated to suicide risk or was too distally related to have a measurable effect. Results do not support the interpersonal‐psychological theory's hypothesis that combat exposure should be indirectly related to suicide risk through acquired fearlessness of death.
Evaluation of the alcoholic fermentation kinetics of enzymatic hydrolysates from sugarcane bagasse (Saccharum officinarum L.)
Authors: Ramos de Andrade Rafael , Cândida Rabelo Sarita , Maugeri Filho Francisco , Maciel Filho Rubens , Carvalho da Costa Aline 
Published: October 2012

AbstractBackgroundThe efficient production of bioethanol by Saccharomyces cerevisiae using lignocellulosic biomass as raw material depends on the fermentability of the hydrolysates. In this work the evaluation of the kinetics of ethanol production by S. cerevisiae using enzymatic hydrolysates was performed and compared with the kinetics of diluted sugarcane molasses fermentation.ResultsA term for inhibition by acetic acid was added to a previous model, the kinetic parameters were re‐estimated and the model has been shown to describe accurately new experiments with distinct hydrolysates proportions as fermentative media. Among all the kinetic parameters, a great reduction in μmax (from 0.437 to 0.37 h−1, at 34°C), and increment in Ypx (from 9.89 to 16.63 kg kg−1, at 34°C) were noted, which strongly affected the kinetics of fermentation.ConclusionsThe kinetic parameters obtained for hydrolysates differed very significantly from those obtained using molasses, which shows that models developed to describe the kinetics of first generation ethanol production need to be reformulated and adapted to describe the kinetics of second generation ethanol fermentation. The productivities achieved were between 1 and 3 kg m‐3 h−1, which are considered acceptable for alcoholic fermentations in batch mode, showing the good fermentability of hydrolysates even without detoxification. © 2012 Society of Chemical Industry
Cornification in reptilian epidermis occurs through the deposition of keratin‐associated beta‐proteins (beta‐keratins) onto a scaffold of intermediate filament keratins
Authors: Alibardi Lorenzo 
Published: October 2012

AbstractThe isolation of genes for alpha‐keratins and keratin‐associated beta‐proteins (formerly beta‐keratins) has allowed the production of epitope‐specific antibodies for localizing these proteins during the process of cornification epidermis of reptilian sauropsids. The antibodies are directed toward proteins in the alpha‐keratin range (40–70 kDa) or beta‐protein range (10–30 kDa) of most reptilian sauropsids. The ultrastructural immunogold study shows the localization of acidic alpha‐proteins in suprabasal and precorneous epidermal layers in lizard, snake, tuatara, crocodile, and turtle while keratin‐associated beta‐proteins are localized in precorneous and corneous layers. This late activation of the synthesis of keratin‐associated beta‐proteins is typical for keratin‐associated and corneous proteins in mammalian epidermis (involucrin, filaggrin, loricrin) or hair (tyrosine‐rich or sulfur‐rich proteins). In turtles and crocodilians epidermis, keratin‐associated beta‐proteins are synthesized in upper spinosus and precorneous layers and accumulate in the corneous layer. The complex stratification of lepidosaurian epidermis derives from the deposition of specific glycine‐rich versus cysteine‐glycine‐rich keratin‐associated beta‐proteins in cells sequentially produced from the basal layer and not from the alternation of beta‐ with alpha‐keratins. The process gives rise to Oberhäutchen, beta‐, mesos‐, and alpha‐layers during the shedding cycle of lizards and snakes. Differently from fish, amphibian, and mammalian keratin‐associated proteins (KAPs) of the epidermis, the keratin‐associated beta‐proteins of sauropsids are capable to form filaments of 3–4 nm which give rise to an X‐ray beta‐pattern as a consequence of the presence of a beta‐pleated central region of high homology, which seems to be absent in KAPs of the other vertebrates. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.