bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavior of Clustered State above the Curie Temperature in La0.78Ca0.22MnO3 Single Crystal
Authors: Ryzhov V.A. , Lazuta A.V. , Smirnov O.P. , Khavronin V.P. , Molkanov P.L. , Mukovskii Y.M. , Chichkov V.I.
Published: December 2010

The results of structural neutron diffraction study and the data on the transport and magnetic properties (the linear and nonlinear (second and third order) susceptibilities) are presented for the La0.88Ca0.22MnO3 single crystal. This compound has the orthorhombic Pbnm space group, showing no structural transformations between 90 K and 300 K. It exhibits the paramagnet-ferromagnet (P-F) (TC  186 K) and insulator – metal (I-M) (ТIM  201 K > TC) phase transitions. The measurements of the second harmonic of the magnetization in the parallel ac and dc H magnetic fields, M2(H,T), showed that below T* 252 K, the FM clusters appear in the PI matrix undergoing the second-order transition. The concentration of the FM clusters increases with cooling so that it is above the percolative threshold value below TIM, and the sample exhibits metallic behavior. The M2(H) hysteresis loops possess a high sensitivity to the I-M transition. Their usual central symmetry is broken in the vicinity of TIM and the loops become asymmetric. This effect is attributed to cluster link nucleation-and-growth process.
Concentration Dependence of Localized Magnetic Moments of Hybridized Electron States at the Impurities of Transition Elements in Semiconductors
Authors: Okulov V.I. , Pamyatnykh E.A. , Zabaznov Y.V.
Published: December 2010

Based on a simple model, theoretical description of localized spins of hybridized electron states of donor impurities in the conduction band of asemiconductor has been developed. Equations are formulated and solved numerically that describe the concentration dependence of localized spins. It is shown that they can exist and reach maximal values in a certain interval of impurity concentration in the vicinity of its value, at which the Fermi energy of the electronic system coincides with the energy level of the donor impurity. The conclusions obtained are compared with the results of Anderson’s theory.
Magnetooptics of Fe/Cr Superlattices
Authors: Lobov I.D. , Kirillova M.M. , Makhnev A.A. , Romashev L.N. , Ustinov V.V.
Published: December 2010

The magnetooptical and optical properties, and giant magnetoresistance (GMR) of MBE-grown Fe(tx, Å)/Cr10 Å (tx=0.3-30 Å) superlattices and nanostructured multilayers are studied. The data obtained are used for characterization of magnetic clusters in structures with ultrathin Fe layers (tFe<6.6 Å) and for estimation of interfacial electron scattering parameters in GMR superlattices.
Magnetooptical Studies of Nanoparticle-Containing Borate Glasses
Authors: Edelman I.S. , Ivanova O.S. , Ivantsov R.D.
Published: December 2010

Faraday rotation (FR) and magnetic circular dichroism (MCD) of nanocomposite structures based on potassium-aluminum-germanium-boron glasses co-doped with Fe and rare earth (RE) or Y+Bi oxides have been studied. Formation of magnetic nanoparticles as a result of the glass heat treatment ensures them magnetic and magneto-optical properties typical of magnetically ordered substances. At the same time, glasses keep transparence in visual spectral range owing to low paramagnetic oxides concentration. FR and MCD spectra of the heat treated glasses are shown to be very close to those of γ-Fe2O3 and practically independent of the RE element nature for the light wave energies lower than 22000 cm-1. For higher energies, the MCD spectrum shape depends strongly on RE what evidences the different origin of magneto-optical effects in two spectral ranges.
Magnetoresistivity and Hall Effect in Mixed and Normal States of Electron-Doped Superconductor Nd2-XCexCuO4+δ with Nonstoichiometric Disorder
Authors: Charikova T.B. , Shelushinina N.G. , Harus G.I. , Petukhov D.S. , Sochinskaya O.E. , Ivanov A.A.
Published: December 2010

Magnetoresistivity and Hall effect measured in magnetic fields up to B=9T (B ║ c, J ║ ab) in electron-doped Nd2−xCexCuO4+δ single crystal films with x = 0.15 and different oxygen content (δ) were studied in a temperature range of 0.4-4.2 K. The resistivity and Hall coefficient behaviors in the mixed state are discussed in the framework of flux-flow model with the inclusion of the back-flow of vortices owing to the pinning forces.
Faraday Rotation Caused by Mixed Valence Centers in Magnetic Crystals
Authors: Falkovskaya L.D. , Fishman Anatoly Yakovlevich , Mitrofanov Valentin Yakovlevich , Tsukerblat B.S.
Published: December 2010

The peculiarities of the Faraday rotation in the imperfect garnet-type crystals for which the lattice irregularities are represented by the mixed valence clusters of transition metal ions are analyzed. The model takes into account the cubic and low symmetry crystal fields acting on the metal ions and migration of the “extra” hole. The electric dipole transitions in these types of clusters with migrating hole coupled to the spin core through the double exchange mechanism are shown to lead to a significant magnetooptical activity in the visible range of spectrum. The intensity of these transitions can be comparable or higher than those for the magnetic dipole ones in the same range of frequencies.
Optical Anisotropy of RMnO3 Manganites in the Range of 4f-4f Transitions
Authors: Loshkareva Natalia N. , Mostovshchikova Elena V. , Moskvin A.S. , Naumov Sergey V. , Kostromitina Natalia V. , Balbashov A.M.
Published: December 2010

Optical absorption of orthorhombic and hexagonal manganites RMnO3 (R= Pr3+, Gd3+, Sm3+, Eu3+, Ho3+, Tm3+, Er3+, and Yb3+) were studied in polarized light in the near- and mid-infrared range for the temperature range 80 - 300 K. Several spectral features associated with 4f-4f transitions of R3+ ions were found in the transparency window of RMnO3. Anisotropy of the absorption spectra in the range of multiplet 4f-4f transitions and changes in populations of the multiplet levels with temperature were observed.
Effect of Severe Plastic Deformation by Torsion on Structure and Properties of Ni54Mn21Ga25 and Ni54Mn20Fe1Ga25
Authors: Kourov N.I. , Pushin Vladimir , Korolev A.V. , Marchenkov V. , Marchenkova E. , Kazantsev V.A. , Weber H.W.
Published: December 2010

We report on the effect of severe plastic deformation by torsion under the Bridgman anvil pressure (SPDT) on structure and physical properties of the Ni54Mn21Ga25 and Ni54Mn20Fe1Ga25 alloys. Two types of samples were studied: ordered (cast) samples and nanocrystalline samples disordered by SPDT. The thermal expansion, thermo EMF, electro- and magnetoresistivity, Hall effect, and magnetization were measured from 4.2 to 800 K and in magnetic fields of up to 15T. We show that the deviation from the stoichiometric Ni50Mn25Ga25 composition shifts the temperatures of the martensitic transition TM and the magnetic (Curie) transition TC to room temperature. Large changes in the physical properties near TM and TC were discovered. The alloys become amorphous and nanocrystalline after the SPDT treatment. This process is accompanied by the disappearance of the martensitic transformations and of the nanocrystalline modulated substructures and, consequently, by the suppression of the magnetic shape-memory effect. The physical properties of the disordered alloys are also strongly changed. Subsequent annealing at Т ≥ 700 K leads to a practically full restoration of the structure and all properties characteristic of the initial cast alloys.
Influence of Glass Matrix on Magneto-Optical Activity of f-f Transitions in Dy3+ Ion
Authors: Sukhachev A.L. , Strokova A.Y. , Malakhovskii A.V.
Published: December 2010

The absorption and magnetic circular dichroism spectra of f-f transitions 6H15/2 → 6F3/2, 6F5/2 , 6(F7/2 +H5/2) and 6(F9/2+H7/2) in Dy3+ ion were studied in the glasses: Dy2O3-P2O5-SiO2-GeO2 and Dy2O3-La2O3-Al2O3-B2O3-SiO2-GeO2 with different concentrations of Dy3+ ions in temperature range 100-300 K. Basing on this data, absolute values and temperature dependences of the paramagnetic magneto-optical activity (MOA) of the transitions were determined. The origin of the MOA of f-f transitions was analyzed with the help of two models. In the first model, MOA is considered as a consequence of admixture of states with opposite parity by odd components of crystal field. The second approach is based on the Judd-Ofelt theory. The same f-f transitions reveal different values and temperature dependences in different glasses, what testifies to a different symmetry of the nearest environment of Dy3+ ions in these glasses.
Effect of Short Antiferromagnetic Correlations on the Normal and Superconducting Properties in Copper Oxides
Authors: Ovchinnikov S.G. , Korshunov M.M. , Shneyder E.I.
Published: December 2010

The abnormal “normal” state and origin of high temperature superconductivity in cuprates are still not clear [1, 2]. The strong electron correlations (SEC) are known to be one of the main difficulties for the theory of high- cuprates. The conventional LDA (local density approximation) approach to the band structure fails in the regime of SEC. Various realistic multiband models of a layer at low energy result in the effective Hubbard or models [3 7]. The hybrid LDA+GTB scheme [8] generates the low-energy effective model with all parameters calculated ab initio.
Nonlinear Spin Dynamics in Magnetic Mesostructures Induced by Spin Polarized Autoemission
Authors: Chinenkov Maksim , Popkov A.F. , Korneev V.I. , Mazurkin N.A. , Dyuzhev N.A.
Published: December 2010

The work is devoted to the discussion of magnetic dynamics features in mesoscopic magnetic structures under the action of spin transport and spin-torque transfer in the nanopillar structures. Tunneling magnetic structure consisting of autoemission cathode and patterned magnetic anode is considered. Main bifurcation changes in the states of a dynamical system, that models mesoscopic structure, are discussed for varied spin polarized current and an external magnetic field.
Autoresonance Parametric Excitation of the Magnetic Breather in a Uniaxial Ferromagnet
Authors: Nazarov V.N. , Kalyakin L.A. , Shamsutdinov M.A.
Published: December 2010

The paper investigates the autoresonance parametric method of excitation of a magnetization breather in a uniaxial ferromagnet by an external alternating magnetic field. The breather excitation threshold has been determined, as well as its dependence on the material quality factor.
EBV Lytic-Phase Protein BGLF5 Contributes to TLR9 Downregulation during Productive Infection
Authors: van Gent Michiel , Griffin Bryan D. , Berkhoff Eufemia G. , van Leeuwen Daphne , Boer Ingrid G. J. , Buisson Marlyse , Hartgers Franca C. , Burmeister Wim P. , Wiertz Emmanuel J. , Ressing Maaike E.
Published: December 2010

Viruses use a wide range of strategies to modulate the host immune response. The human gammaherpesvirus EBV, causative agent of infectious mononucleosis and several malignant tumors, encodes proteins that subvert immune responses, notably those mediated by T cells. Less is known about EBV interference with innate immunity, more specifically at the level of TLR-mediated pathogen recognition. The viral dsDNA sensor TLR9 is expressed on B cells, a natural target of EBV infection. Here, we show that EBV particles trigger innate immune signaling pathways through TLR9. Furthermore, using an in vitro system for productive EBV infection, it has now been possible to compare the expression of TLRs by EBV− and EBV+ human B cells during the latent and lytic phases of infection. Several TLRs were found to be differentially expressed either in latently EBV-infected cells or after induction of the lytic cycle. In particular, TLR9 expression was profoundly decreased at both the RNA and protein levels during productive EBV infection. We identified the EBV lytic-phase protein BGLF5 as a protein that contributes to downregulating TLR9 levels through RNA degradation. Reducing the levels of a pattern-recognition receptor capable of sensing the presence of EBV provides a mechanism by which the virus could obstruct host innate antiviral responses.
A Human NK Cell Activation/Inhibition Threshold Allows Small Changes in the Target Cell Surface Phenotype To Dramatically Alter Susceptibility to NK Cells
Authors: Holmes Tim D. , El-Sherbiny Yasser M. , Davison Adam , Clough Sally L. , Blair G. Eric , Cook Graham P.
Published: December 2010

NK cell activation is negatively regulated by the expression of target cell MHC class I molecules. We show that this relationship is nonlinear due to an NK cell activation/inhibition threshold. Ewing’s sarcoma family tumor cell monolayers, which were highly susceptible to NK cells in vitro, developed a highly resistant phenotype when cultured as three-dimensional multicellular tumor spheroid structures. This suggested that tumor architecture is likely to influence the susceptibility to NK cells in vivo. Resistance of the multicellular tumor spheroid was associated with the increased expression of MHC class I molecules and greatly reduced NK cell activation, implying that a threshold of NK cell activation/inhibition had been crossed. Reducing MHC class I expression on Ewing’s sarcoma family tumor monolayers did not alter their susceptibility to NK cells, whereas increased expression of MHC class I rendered them resistant and allowed the threshold point to be identified. This threshold, as defined by MHC class I expression, was predictive of the number of NK-resistant target cells within a population. A threshold permits modest changes in the target cell surface phenotype to profoundly alter the susceptibility to NK cells. Whereas this allows for the efficient detection of target cells, it also provides a route for pathogens and tumors to evade NK cell attack.
Autophagy Regulates Endoplasmic Reticulum Homeostasis and Calcium Mobilization in T Lymphocytes
Authors: Jia Wei , Pua Heather H. , Li Qi-Jing , He You-Wen
Published: December 2010

Macroautophagy (hereafter referred to as autophagy) is an evolutionarily conserved intracellular bulk degradation pathway that plays critical roles in eliminating intracellular pathogens, presenting endogenous Ags, and regulating T lymphocyte survival and proliferation. In this study, we have investigated the role of autophagy in regulating the endoplasmic reticulum (ER) compartment in T lymphocytes. We found that ER content is expanded in mature autophagy-related protein (Atg) 7-deficient T lymphocytes. Atg7-deficient T cells stimulated through the TCR display impaired influx, but not efflux, of calcium, and ER calcium stores are increased in Atg7-deficient T cells. Treatment with the ER sarco/ER Ca2+-ATPase pump inhibitor thapsigargin rescues the calcium influx defect in Atg7-deficient T lymphocytes, suggesting that this impairment is caused by an intrinsic defect in ER. Furthermore, we found that the stimulation-induced redistribution of stromal interaction molecule-1, a critical event for the store-operated Ca2+ release-activated Ca2+ channel opening, is impaired in Atg7-deficient T cells. Together, these findings indicate that the expanded ER compartment in Atg7-deficient T cells contains increased calcium stores, and the inability of these stores to be depleted causes defective calcium influx in these cells. Our results demonstrate that autophagy plays an important role in maintaining ER and calcium homeostasis in T lymphocytes.
Senescent CD14+CD16+ Monocytes Exhibit Proinflammatory and Proatherosclerotic Activity
Authors: Merino Ana , Buendia Paula , Martin-Malo Alejandro , Aljama Pedro , Ramirez Rafael , Carracedo Julia
Published: December 2010

In elderly subjects and in patients with chronic inflammatory diseases, there is an increased subset of monocytes with a CD14+CD16+ phenotype, whose origin and functional relevance has not been well characterized. In this study, we determined whether prolonged survival of human CD14++CD16− monocytes promotes the emergence of senescent cells, and we analyzed their molecular phenotypic and functional characteristics. We used an in vitro model to prolong the life span of healthy monocytes. We determined cell senescence, intracellular cytokine expression, ability to interact with endothelial cells, and APC activity. CD14+CD16+ monocytes were senescent cells with shortened telomeres (215 ± 37 relative telomere length) versus CD14++CD16− cells (339 ± 44 relative telomere length; p < 0.05) and increased expression of β-galactosidase (86.4 ± 16.4% versus 10.3 ± 7.5%, respectively; p = 0.002). CD14+CD16+ monocytes exhibited features of activated cells that included expression of CD209, release of cytokines in response to low-intensity stimulus, and increased capacity to sustain lymphocyte proliferation. Finally, compared with CD14++CD16− cells, CD14+CD16+ monocytes showed elevated expression of chemokine receptors and increased adhesion to endothelial cells (19.6 ± 8.1% versus 5.3 ± 4.1%; p = 0.033). In summary, our data indicated that the senescent CD14+CD16+ monocytes are activated cells, with increased inflammatory activity and ability to interact with endothelial cells. Therefore, accumulation of senescent monocytes may explain, in part, the development of chronic inflammation and atherosclerosis in elderly subjects and in patients with chronic inflammatory diseases.
Lung Cancer-Derived Galectin-1 Mediates Dendritic Cell Anergy through Inhibitor of DNA Binding 3/IL-10 Signaling Pathway
Authors: Kuo Po-Lin , Hung Jen-Yu , Huang Shau-Ku , Chou Shah-Hwa , Cheng Da-En , Jong Yuh-Jyh , Hung Chih-Hsing , Yang Chih-Jen , Tsai Ying-Ming , Hsu Ya-Ling , Huang Ming-Shyan
Published: December 2010

Lung cancer, one of the leading causes of death worldwide, is often associated with a state of immune suppression, but the molecular and functional basis remains enigmatic. Evidence is provided in this paper supporting the role of lung cancer-derived soluble lectin, galectin-1, as a culprit in dendritic cell (DC) anergy. We have shown that galectin-1 is highly expressed in lung cancer cell lines, together with the serum and surgical samples from lung cancer patients. Functionally, lung cancer-derived galectin-1 has been shown to alter the phenotypes of monocyte-derived DCs (MdDCs) and impair alloreactive T cell response, concomitant with the increase of CD4+CD25+FOXP3+ regulatory T cells. The regulatory effect of galectin-1 is mediated, in part, through its ability to induce, in an Id3 (inhibitor of DNA binding 3)-dependent manner, the expression of IL-10 in monocytes and MdDCs. This effect is inhibited by the addition of lactose, which normalizes the phenotypic and functional alterations seen in MdDCs. Of note, significant upregulation of IL-10 was seen in tumor-infiltrating CD11c+ DCs in human lung cancer samples. This was also noted in mice transplanted with lung cancer cells, but not in those receiving tumor cells with galectin-1 knockdown. Furthermore, a significant reduction was noted in lung cancer incidence and in the levels of IL-10–expressing, tumor-infiltrating DCs, in mice receiving galectin-1–silenced tumor cells. These results thus suggest that the galectin-1/IL-10 functional axis may be crucial in lung cancer-mediated immune suppression, and that galectin-1 may serve as a target in the development of lung cancer immunotherapy.
Cutting Edge: NLRC5-Dependent Activation of the Inflammasome
Authors: Davis Beckley K. , Roberts Reid A. , Huang Max T. , Willingham Stephen B. , Conti Brian J. , Brickey W. June , Barker Brianne R. , Kwan Mildred , Taxman Debra J. , Accavitti-Loper Mary-Ann , Duncan Joseph A. , Ting Jenny P.-Y.
Published: December 2010

The nucleotide-binding domain leucine-rich repeat-containing proteins, NLRs, are intracellular sensors of pathogen-associated molecular patterns and damage-associated molecular patterns. A subgroup of NLRs can form inflammasome complexes, which facilitate the maturation of procaspase 1 to caspase 1, leading to IL-1β and IL-18 cleavage and secretion. NLRC5 is predominantly expressed in hematopoietic cells and has not been studied for inflammasome function. RNA interference-mediated knockdown of NLRC5 nearly eliminated caspase 1, IL-1β, and IL-18 processing in response to bacterial infection, pathogen-associated molecular patterns, and damage-associated molecular patterns. This was confirmed in primary human monocytic cells. NLRC5, together with procaspase 1, pro–IL-1β, and the inflammasome adaptor ASC, reconstituted inflammasome activity that showed cooperativity with NLRP3. The range of pathogens that activate NLRC5 inflammasome overlaps with those that activate NLRP3. Furthermore, NLRC5 biochemically associates with NLRP3 in a nucleotide-binding domain-dependent but leucine-rich repeat-inhibitory fashion. These results invoke a model in which NLRC5 interacts with NLRP3 to cooperatively activate the inflammasome.
CD1d-Restricted IFN-γ–Secreting NKT Cells Promote Immune Complex-Induced Acute Lung Injury by Regulating Macrophage-Inflammatory Protein-1α Production and Activation of Macrophages and Dendritic Cells
Authors: Kim Ji Hyung , Chung Doo Hyun
Published: December 2010

Immune complex-induced acute lung injury (IC-ALI) has been implicated in various pulmonary disease states. However, the role of NKT cells in IC-ALI remains unknown. Therefore, we explored NKT cell functions in IC-ALI using chicken egg albumin and anti-chicken egg albumin IgG. The bronchoalveolar lavage fluid of CD1d−/− and Jα18−/− mice contained few Ly6G+CD11b+ granulocytes, whereas levels in B6 mice were greater and were increased further by α-galactosyl ceramide. IFN-γ and MIP-1α production in the lungs was greater in B6 than CD1d−/− mice. Adoptive transfer of wild type (WT) but not IFN-γ–, MIP-1α–, or FcγR-deficient NKT cells into CD1d−/− mice caused recruitment of inflammatory cells to the lungs. Moreover, adoptive transfer of IFN-γR–deficient NKT cells enhanced MIP-1α production and cell recruitment in the lungs of CD1d−/− or CD1d−/−IFN-γ−/− mice, but to a lesser extent than WT NKT cells. This suggests that IFN-γ–producing NKT cells enhance MIP-1α production in both an autocrine and a paracrine manner. IFN-γ–deficient NKT cells induced less IL-1β and TNF-α production by alveolar macrophages and dendritic cells in CD1d−/− mice than did WT NKT cells. Taken together, these data suggest that CD1d-restricted IFN-γ–producing NKT cells promote IC-ALI by producing MIP-1α and enhancing proinflammatory cytokine production by alveolar macrophages and dendritic cells.
Glycogen Synthase Kinase-3 Is an Early Determinant in the Differentiation of Pathogenic Th17 Cells
Authors: Beurel Eléonore , Yeh Wen-I , Michalek Suzanne M. , Harrington Laurie E. , Jope Richard S.
Published: December 2010

CD4+ T cells are critical for host defense but are also major drivers of immune-mediated diseases. The classical view of Th1 and Th2 subtypes of CD4+ T cells was recently revised by the identification of the Th17 lineage of CD4+ T cells that produce IL-17, which have been found to be critical in the pathogenesis of autoimmune and other diseases. Mechanisms controlling the differentiation of Th17 cells have been well described, but few feasible targets for therapeutically reducing Th17 cells are known. The generation of Th17 cells requires IL-6 and activation of STAT3. During polarization of CD4+ T cells to Th17 cells, we found that inhibition of glycogen synthase kinase-3 (GSK3) blocked IL-6 production, STAT3 activation, and polarization to Th17 cells. Polarization of CD4+ T cells to Th17 cells increased by 10-fold the expression of GSK3β protein levels in Th17 cells, whereas GSK3β was unaltered in regulatory T cells. Diminishing GSK3 activity either pharmacologically or molecularly blocked Th17 cell production, and increasing GSK3 activity promoted polarization to Th17 cells. In vivo inhibition of GSK3 in mice depleted constitutive Th17 cells in intestinal mucosa, blocked Th17 cell generation in the lung after Francisella tularensis infection, and inhibited the increase in spinal cord Th17 cells and disease symptoms in the experimental autoimmune encephalomyelitis mouse model of multiple sclerosis. These findings identify GSK3 as a critical mediator of Th17 cell production and indicate that GSK3 inhibitors provide a potential therapeutic intervention to control Th17-mediated diseases.
Relationship between Fibroblast Growth Factor-23 and Mineral Metabolism in Chronic Kidney Disease
Authors: Nitta Kosaku
Published: December 2010

Fibroblast growth factor- (FGF-)23 is a recently discovered regulator of calcium-phosphate metabolism. FGF-23 appears to decrease in synthesis and accelerated degradation of 1,25(OH)2D. Together with its cofactor Klotho, FGF-23 maintains serum phosphate levels within the normal range by increasing renal phosphate excretion. In chronic kidney disease (CKD), FGF-23 levels rise in parallel with the decline in renal function long before a significant increase in serum phosphate concentration occurs. Both Klotho and FGF-23, linked by a receptor mechanism, affect vitamin D synthesis and parathyroid hormone (PTH) secretion. Previous studies have shown a close association between reduced FGF-23 or Klotho activities and vascular calcification. The possible association of FGF-23 and left ventricular hypertrophy or vascular dysfunction has been proposed. Finally, prospective studies have shown that high serum FGF-23 concentrations predict more rapid disease progression in CKD patients who were not on dialysis and increased mortality in patients on maintenance hemodialysis. FGF-23 may therefore prove to be an important therapeutic target for the management of CKD.
Molecular Adaptation of Modern Human Populations
Authors: Shi Hong , Su Bing
Published: December 2010

Modern humans have gone through varied processes of genetic adaptations when their ancestors left Africa about 100,000 years ago. The environmental stresses and the social transitions (e.g., emergence of the Neolithic culture) have been acting as the major selective forces reshaping the genetic make-up of human populations. Genetic adaptations have occurred in many aspects of human life, including the adaptation to cold climate and high-altitude hypoxia, the improved ability of defending infectious diseases, and the polished strategy of utilizing new diet with the advent of agriculture. At the same time, the adaptations once developed during evolution may sometimes generate deleterious effects (e.g., susceptibility to diseases) when facing new environmental and social changes. The molecular (especially the genome-wide screening of genetic variations) studies in recent years have detected many genetic variants that show signals of Darwinian positive selection in modern human populations, which will not only provide a better understanding of human evolutionary history, but also help dissecting the genetic basis of human complex diseases.
Inflammatory Mechanisms of Neurodegeneration in Toxin-Based Models of Parkinson's Disease
Authors: Litteljohn Darcy , Mangano Emily , Clarke Melanie , Bobyn Jessica , Moloney Kerry , Hayley Shawn
Published: December 2010

Parkinson's disease (PD) has been associated with exposure to a variety of environmental agents, including pesticides, heavy metals, and organic pollutants; and inflammatory processes appear to constitute a common mechanistic link among these insults. Indeed, toxin exposure has been repeatedly demonstrated to induce the release of oxidative and inflammatory factors from immunocompetent microglia, leading to damage and death of midbrain dopamine (DA) neurons. In particular, proinflammatory cytokines such as tumor necrosis factor-αand interferon-γ, which are produced locally within the brain by microglia, have been implicated in the loss of DA neurons in toxin-based models of PD; and mounting evidence suggests a contributory role of the inflammatory enzyme, cyclooxygenase-2. Likewise, immune-activating bacterial and viral agents were reported to have neurodegenerative effects themselves and to augment the deleterious impact of chemical toxins upon DA neurons. The present paper will focus upon the evidence linking microglia and their inflammatory processes to the death of DA neurons following toxin exposure. Particular attention will be devoted to the possibility that environmental toxins can activate microglia, resulting in these cells adopting a “sensitized” state that favors the production of proinflammatory cytokines and damaging oxidative radicals.
Cellular Senescence as a Target in Cancer Control
Authors: Vergel Mar , Marin Juan J. , Estevez Purificacion , Carnero Amancio
Published: December 2010

Somatic cells show a spontaneous decline in growth rate in continuous culture. This is not related to elapsed time but to an increasing number of population doublings, eventually terminating in a quiescent but viable state termedreplicative senescence. These cells are commonly multinucleated and do not respond to mitogens or apoptotic stimuli. Cells displaying characteristics of senescent cells can also be observed in response to other stimuli, such as oncogenic stress, DNA damage, or cytotoxic drugs and have been reported to be foundin vivo. Most tumors show unlimited replicative potential, leading to the hypothesis that cellular senescence is a natural antitumor program. Recent findings suggest that cellular senescence is a natural mechanism to prevent undesired oncogenic stress in somatic cells that has been lost in malignant tumors. Given that the ultimate goal of cancer research is to find the definitive cure for as many tumor types as possible, exploration of cellular senescence to drive towards antitumor therapies may decisively influence the outcome of new drugs. In the present paper, we will review the potential of cellular senescence to be used as target for anticancer therapy.
Effectiveness of a Worksite Telephone-Based Weight Management Program
Authors: Terry Paul E. , Seaverson Erin L. D. , Grossmeier Jessica , Anderson David R.
Published: December 2010

Purpose.

Examine the long-term impact of a telephone-based weight management program among participants recruited from worksite settings.

Design.

Pre/post quasi-experimental design comparing weight loss and related behaviors between program completers and noncompleters.

Setting.

Ten large private-sector and public-sector employers.

Subjects.

Overweight or obese participants (n = 1298) enrolled in a telephone-based weight management program.

Intervention.

Individually tailored telephone-based weight management coaching program that included up to five calls over a median of 250 days.

Measures.

Weight, body mass index, and lifestyle behaviors assessed via health risk assessment at baseline and 1-year follow-up.

Analysis.

Chi-square and one-way analysis of variance procedures were used to assess between-group differences in weight and associated behaviors, with criterion for significance set at p < .05.

Results.

Among weight management program participants, 48% of program completers and 47% of noncompleters lost weight, but program completers averaged 2.6 times more weight loss than noncompleters. Improvements in physical activity, eating habits, and overall health status were reported for completers.

Conclusion.

The weight loss attained among participants who lost weight, along with the improvements in physical activity and nutrition practices, suggests that a telephone-based weight management program of modest intensity can have a positive impact on the health of obese or overweight worksite participants. (Am J Health Promot 2011;25[3]:186–189.)
Active Commuting and Habit Strength: An Interactive and Discriminant Analyses Approach
Authors: de Bruijn Gert-Jan , Gardner Benjamin
Published: December 2010

Purpose.

Habits may be a mechanism linking environmental variables with active commuting. This study investigated the role of habit strength in the explanation of active commuting across profiles based on current active commuting, motivation, and habit strength within the framework of the theory of planned behavior (TPB).

Design.

Cross-sectional survey using validated questionnaires.

Setting.

Undergraduate students who participated for course credits.

Subjects.

Five hundred and thirty-eight students (mean age = 21.19 [SD = 2.57]; 28.45% males; response rate = 86.36%).

Measures.

Questionnaire included TPB items, underlying beliefs, and a validated measure of habit strength. Active commuting was assessed with relevant items from the International Physical Activity Questionnaire.

Analysis.

Hierarchical regression and interaction analyses, discriminant function analysis, and analyses of variance.

Results.

Habit strength was the strongest correlate of active commuting and interacted with intention: at low and medium levels of habit strength, the intention–bicycle use relationship was more than twice as strong as at high levels. Beliefs regarding situational barriers were amongst the most discriminating beliefs, whereas beliefs regarding health benefits did not distinguish profiles.

Conclusions.

Stronger active commuting habits are associated with a lower association between intention and bicycle use. Persuasive health campaigns might more usefully instill a sense of confidence in various commuting situations rather than merely emphasizing health benefits of active commuting. (Am J Health Promot 2011;25[3]:e27–e36.)
Corporate governance, corporate social responsibility and corporate performance
Authors: Huang Chi-Jui
Published: December 2010

Previous research has analyzed and debated corporate governance (CG) and corporate social responsibility (CSR) independently. This paper aims to empirically explore the interrelationship between CG, CSR, financial performance (FP) and Corporate Social Performance (CSP) using a sample of 297 electronics companies operating in Taiwan, a newly industrialized Asian economy. The results show that a CG model which includes independent outside directors and which has specific ownership characteristics has a significantly positive impact on both FP and CSP, whereas FP itself does not influence CSP. The presence of independent outside directors in the firm has the greatest impact on the social performance of the firm's worker, customer, supplier, community and society dimensions. Government shareholders enhance a firm's social performance extraordinarily because government shareholders will be more likely to request that companies fulfill their social responsibilities. Only government shareholders positively and significantly relate to a firm's environmental performance. Furthermore, foreign institutional stockholders help to increase worker and supplier performance by paying more attention to employee policies and supply chain relationships. Finally, independent outside directors, foreign institutional stockholders and domestic financial institutional stockholders are shown to improve financial performance.
A qualitative analysis of intellectual capital in social service non-profit organisations: A theory–practice divide
Authors: Kong Eric , Ramia Gaby
Published: December 2010

The paper contributes to debates on non-profit strategy, first by arguing that intellectual capital (IC) can be utilised as a non-profit strategic management conceptual framework and second by highlighting nuances in the meaning and significance of IC. In responding to the public management agendas of government, non-profit organisations (NPOs) have had to commercialise their strategies. On the basis of data from in-depth interviews with 35 senior non-profit managers across 22 large Australian social service non-profit organisations (SSNPOs), the analysis confirms that IC assists SSNPOs in managing the social–commercial divide, but that managers' understandings of the IC concept are often different to those contained in the IC literature. IC scholars suggest that IC is synergetic with its components being inter-dependent. The managers perceived that very few inter-relationships existed between IC components. Implications of the theory—practice divide for non-profit strategy are discussed. Research limitations and future research direction are presented in the paper.
Enhancing learning outcomes through group work in an internationalised undergraduate business education context
Authors: Hunter James D , Vickery Jo , Smyth Robyn
Published: December 2010

Employers of business graduates require them to be effective communicators and team members in twenty-first century work environments. As a means of developing these skills, we believe group work is important to an undergraduate business teaching pedagogy preparing graduates for the challenges of modern workplaces. Student responses to a series of qualitative and quantitative focus group activities highlighted the ‘big issues’ encountered in group activities involving an increasingly internationalised and diverse cohort of students. These issues related mainly to communication within the group and the fear of social-loafers. These insights established the basis on which proactive strategies were introduced in a subsequent teaching period to nurture and advance the quality of the learning experience within a tertiary undergraduate business education setting. Given that reduced Government funding to Australian universities has prompted the management of institutions to look to full-fee paying international students to offset shortfalls in their operating budgets, this paper explores the particular impact of increasing numbers of English as a Second Language (ESL) students on the quality of, and student receptiveness to, group based study activities.
Research in strategy–structure–performance construct: Review of trends, paradigms and methodologies
Authors: Amitabh Manu , Gupta Rajen K
Published: December 2010

With rising unpredictability of the business environment, the strategy–structure–performance construct is being questioned afresh. But cutting edge research evidence is still difficult to come by. One of the possible reasons is that few researchers are adopting new and innovative methodologies. This paper carries out a paradigmatic and methodological review of research on the topic for the last 10 years after classifying published research into three broad categories of enquiry. The study finds that contrary to expectations, the logical positivistic/empiricist paradigm of enquiry into the one way linear causality in the strategy–structure–performance relationship was still the favorite among researchers and may explain the lack of breakthrough contribution of recent research. This paper makes a case for more research on the challenging two-way causality using innovative designs and archival data, and suggests some future directions for research.
A 5-Year Follow-Up of Antioxidant Supplementation in Type 2 Diabetic Retinopathy
Authors: Garcia-Medina Jose Javier , Pinazo-Duran Maria Dolores , Garcia-Medina Manuel , Zanon-Moreno Vicente , Pons-Vazquez Sheila
Published: December 2010

Purpose

This study was designed to evaluate the effect of antioxidant supplementation on diabetic retinopathy (DR) over a 5-year follow-up period. To our knowledge, this is the first such clinical trial performed.

Methods

We recruited 105 type 2 diabetic patients with nonproliferative DR. A complete ophthalmic checkup and a plasma determination of oxidative (malonyldialdehyde [MDA]) and antioxidant parameters (total antioxidant status [TAS]) were obtained as the baseline. One part of the cohort was randomly assigned to oral antioxidant supplementation at nutritional doses. The same examinations were performed with 97 diabetic patients who completed the 5-year follow-up period. The best-corrected visual acuity, DR score, MDA, and TAS values were compared at the beginning and the end of the follow-up.

Results

Best-corrected visual acuity did not change during the follow-up, irrespective of supplementation. However, the retinopathy stage showed a retardation of progression in the subgroup with supplementation, but worsened in the subgroup with no antioxidant supplementation. Furthermore, the antioxidant supplementation group maintained its antioxidant plasma status levels, which was related to decreased oxidative plasma activity.

Conclusions

Oral antioxidant supplementation could be a useful adjunctive long-term therapy in the treatment of nonproliferative DR.
Some Monotonicity Properties of Gamma and q-Gamma Functions
Authors: Gao Peng
Published: December 2010

We prove some monotonicity properties of functions involving gamma and q-gamma functions.
Variable Forgetting Factor LS Algorithm for Polynomial Channel Model
Authors: Kohli Amit Kumar , Rai Amrita , Patel Meher Krishna
Published: December 2010

Variable forgetting factor (VFF) least squares (LS) algorithm for polynomial channel paradigm is presented for improved tracking performance under nonstationary environment. The main focus is on updating VFF when each time-varying fading channel is considered to be a first-order Markov process. In addition to efficient tracking under frequency-selective fading channels, the incorporation of proposed numeric variable forgetting factor (NVFF) in LS algorithm reduces the computational complexity.
An Efficient Catalytic Chromium‐Mediated Iodocyclopropanation Reaction: Stereoselective Synthesis of Iodocyclopropanecarboxamides
Authors: Concellón José M. , Rodríguez‐Solla Humberto , Blanco Elena G. , García‐Granda Santiago , Díaz and M. Rosario
Published: December 2010

A catalytic chromium‐mediated novel synthesis of iodocyclopropanecarboxamides is reported. This reaction can be carried out on aromatic (E)‐ or (Z)‐α,β‐unsaturated amides in which the CC double bond is di‐ or trisubstituted. This process takes place with total stereospecificity and the new CI stereogenic center is generated with high stereoselectivity. Some synthetic applications of the obtained iodocyclopropanecarboxamides are also reported. The structures of the iodocyclopropanes and derivatives were established by X‐ray analysis.
Evidence for acute neurotoxicity after chemotherapy
Authors: Petzold Axel , Mondria Tjeerd , Kuhle Jens , Rocca Maria A. , Cornelissen Jan , te Boekhorst Peter , Lowenberg Bob , Giovannoni Gavin , Filippi Massimo , Kappos Ludwig , Hintzen Rogier
Published: December 2010

Objective

Chronic neurotoxicity is a recognized long‐term complication following chemotherapy in a range of diseases. Neurotoxicity adversely affects patients' quality of life. The objective of this study is to examine whether there is evidence of acute neurotoxicity.

Methods

This prospective study included patients with secondary progressive multiple sclerosis (SPMS‐BMT, n = 14) and hematological malignancies (HM‐BMT, n = 17) receiving chemotherapy as preconditioning for bone marrow transplant. The control groups included SPMS patients matched for demographic and clinical data (SPMS‐PL, n = 14) and healthy controls (n = 14). Neurodegeneration was assessed at baseline and longitudinally (months 1, 2, 3, 6, 9, 12, 24, and 36), combining a clinical scale for disability (Expanded Disability Status Scale [EDSS]), a serum protein biomarker for neurodegeneration (neurofilaments, NfH‐SMI35), and brain atrophy measures (magnetic resonance imaging).

Results

Disability progression was significantly more acute and severe following chemotherapy compared to placebo. Immediately after starting chemotherapy, serum NfH‐SMI35 levels increased in 79% (p< 0.0001) of SPMS‐BMT patients and 41% (p< 0.01) of HM‐BMT patients compared to 0% of SPMS‐PL patients or healthy controls. In SPMS‐BMT serum NfH‐SMI35 levels were > 100‐fold higher 1 month after chemotherapy (29.73ng/ml) compared to baseline (0.28ng/ml,p< 0.0001). High serum NfH‐SMI35 levels persisting for at least 3 months were associated with sustained disability progression on the EDSS (p< 0.05). Brain atrophy rates increased acutely in SPMS‐BMT (−2.09) compared to SPMS‐PL (−1.18,p< 0.05).

Interpretation

Neurotoxicity is an unwanted acute side effect of aggressive chemotherapy. ANN NEUROL 2010
The authorship lottery: An impediment to research collaboration?
Authors: Kaufmann Petra , Annis Christine , Griggs Robert C. ,   and the Muscle Study Group Executive Committee
Published: December 2010

Authorship of scientific publications holds great importance for basic and clinical researchers. Academic appointments and promotions, grant funding, and salary support depend to some extent on published recognition through authorship. Peer‐recognition and personal satisfaction are additional incentives for authorship. Some current “rules” and conventions for assigning authorship are based on largely unwritten but widely‐accepted arbitrary decisions. We hypothesize that the inherent uncertainties about assigning “credit where credit is due” serve as a disincentive for clinicians considering an academic career and may discourage or at least impede the collaborations essential to address most translational and clinical research issues. Surveys of the New England Journal of Medicine and the Annals of Neurology suggest that neurologists have been slow to adopt ways of sharing “credit” appropriately. We recommend that authorship of reports of the primary results of multicenter or multidisciplinary studies should be in the name of the group of investigators collaborating on the work. Given the availability of digital methods that could apportion credit quantitatively, academic leaders, including funding agencies and promotions committees, should consider challenging outmoded authorship conventions. Authorship is too important to be left to chance. Ann Neurol 2010;
ChemInform Abstract: New Intermetallics YbAu2In4 and Yb2Au3In5.
Authors: Sebastian C. Peter , Salvador James , Martin Joshua B. , Kanatzidis Mercouri G.
Published: December 2010

Single crystals of the new title compounds are prepared in high yields from the elements using excess In as a flux (1000 °C, 5—72 h).
ChemInform Abstract: Crystal Structure and Physical Properties of Quaternary Clathrates Ba8ZnxGe46‐x‐ySiy, Ba8(Zn,Cu)xGe46‐x and Ba8(Zn,Pd)xGe46‐x.
Authors: Nasir Navida , Grytsiv Andriy , Melnychenko‐Koblyuk Nataliya , Rogl Peter , Bednar Ingeborg , Bauer Ernst
Published: December 2010

Semiconducting clathrate‐type I compounds are of considerable interest for thermoelectric materials.
ChemInform Abstract: High‐Yield Synthesis of Ultralong and Ultrathin Zn2GeO4 Nanoribbons Toward Improved Photocatalytic Reduction of CO2 into Renewable Hydrocarbon Fuel.
Authors: Liu Qi , Zhou Yong , Kou Jiahui , Chen Xiaoyu , Tian Zhongping , Gao Jun , Yan Shicheng , Zou Zhigang
Published: December 2010

Single‐crystalline nanobelts of the title compound with lengths of hundreds of micrometers, thickness as small as ≈7 nm, and aspect ratios of up to 10000 are solvothermally synthesized in high yields from a mixture of GeO2 and Zn(OAc)2 in an en/H2O (2:1) mixed solvent (autoclave, 180 °C, 24 h).
ChemInform Abstract: Exopericyclic Stereocontrol in Johnson—Claisen Rearrangements of Allylic Sulfides.
Authors: Craig Donald , Harvey John W. , O'Brien Alexander G. , White Andrew J. P.
Published: December 2010

The selectivity of the Johnson—Claisen rearrangement of allylic sulfides is highly dependent on the allylic substitution pattern.
ChemInform Abstract: Development of a New Lewis Base‐Tolerant Chiral LBA and Its Application to Catalytic Asymmetric Protonation Reaction.
Authors: Cheon Cheol Hong , Imahori Tatsushi , Yamamoto Hisashi
Published: December 2010

The new system efficiently catalyzes the asymmetric protonation of silyl enol ethers of 2‐substituted cyclic ketones.
ChemInform Abstract: Air‐Stable Iron Catalyst for the Oppenauer‐Type Oxidation of Alcohols.
Authors: Moyer Sara A. , Funk Timothy W.
Published: December 2010

Secondary alcohols are efficiently transformed under the optimized conditions to produce the carbonyl compounds in good to excellent yields.
ChemInform Abstract: Mild and Efficient Method for Synthesis of Enaminones Using Ytterbium Triflate as Catalyst.
Authors: Chen Rener , Li Ping , Li Jianjun , Su Weike
Published: December 2010

The scope of the title reaction is studied.
ChemInform Abstract: Cyanation of Arenes via Iridium‐Catalyzed Borylation.
Authors: Liskey Carl W. , Liao Xuebin , Hartwig John F.
Published: December 2010

The first copper‐mediated oxidative cyanation of arylboronate esters [freshly prepared by borylation of the arenes (I)] or of arylboronic acids such as (IV) or (VI) is reported to proceed with great functional group tolerance.