bluuebunny/crossref_metadata_2025 huggingface dataset:
Millimeter‐wave six‐port in combined microstrip and substrate‐integrated waveguide technologies
Authors: Boukari Bouraima , Moldovan Emilia , Cojocaru Razvan I. , Wu Ke , Bosisio Renato G. , Ovidiu Tatu Serioja
Published: August 2010

A millimeter‐wave six‐port implementation using combined substrate‐integrated waveguide (SIW) and microstrip technologies, and low‐loss short transition between microstrip and SIW is presented. The six‐port is implemented using SIW hybrid couplers with continuous metalized grooves and Wilkinson power dividers. The proposed circuit is suitable for 77‐GHz radar sensor front ends. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2488–2493, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25538
A 7‐ to 14‐GHz GaAs pHEMT LNA with 1.1 dB noise figure and 26 dB gain
Authors: Peng Yang‐Yang , Lu Ke‐Jie , Sui Wen‐Quan
Published: August 2010

A three‐stage 7‐ to 14‐GHz monolithic low‐noise amplifier (LNA) has been fabricated using 0.15‐μm AlGaAs/GaAs pHEMT technology.To achieve ultra low noise figure and wide operation bandwidth, the proposed LNA uses wideband matching network and negative feedback technique. Measured results from 7 to 14 GHz demonstrate a minimum of 1.1 dB noise figure and 26 dB gain. The input and output return loss exceeded 10 dB across the band. These results demonstrate the best performance of AlGaAs/GaAs pHEMT technology for wideband and low noise applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2615–2617, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25547
High raman gain of dispersion compensation fiber using RZ‐DPSK format for long‐haul DWDM transmission system
Authors: Lin Hsiu‐Sheng , Lai Po‐Chou
Published: August 2010

We investigated the transport of a 16 channels 40 Gb/s dense wavelength division multiplexing (DWDM) system which uses high Raman gain of dispersion compensation fiber (DCF) for long‐haul DWDM transmission. Using the return to zero differential phase shift keying (RZ‐DPSK) modulation format with an optimized dispersion compensation format, we demonstrate DWDM transmission with a capacity of 640 Gb/s with 0.4 nm channel spacing over 4500 km of transmission fiber. The transmission system structure uses 120 km single mode fiber and 30 km DCF for thirty spans in the C band wavelength range and a Raman Amplifier with high Raman gain to achieve long‐haul transmission. We also used enhanced forward error correction for high capacity transmission over several thousand kilometers with the RZ‐DPSK modulation format. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2548–2551, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25552
Max CAPR: High‐resolution 3D contrast‐enhanced MR angiography with acquisition times under 5 seconds
Authors: Haider Clifton R. , Borisch Eric A. , Glockner James F. , Mostardi Petrice M. , Rossman Phillip J. , Young Phillip M. , Riederer Stephen J.
Published: August 2010

High temporal and spatial resolution is desired in imaging of vascular abnormalities having short arterial‐to‐venous transit times. Methods that exploit temporal correlation to reduce the observed frame time demonstrate temporal blurring, obfuscating bolus dynamics. Previously, a Cartesian acquisition with projection reconstruction‐like (CAPR) sampling method has been demonstrated for three‐dimensional contrast‐enhanced angiographic imaging of the lower legs using two‐dimensional sensitivity‐encoding acceleration and partial Fourier acceleration, providing 1mm isotropic resolution of the calves, with 4.9‐sec frame time and 17.6‐sec temporal footprint. In this work, the CAPR acquisition is further undersampled to provide a net acceleration approaching 40 by eliminating all view sharing. The tradeoff of frame time and temporal footprint in view sharing is presented and characterized in phantom experiments. It is shown that the resultant 4.9‐sec acquisition time, three‐dimensional images sets have sufficient spatial and temporal resolution to clearly portray arterial and venous phases of contrast passage. It is further hypothesized that these short temporal footprint sequences provide diagnostic quality images. This is tested and shown in a series of nine contrast‐enhanced MR angiography patient studies performed with the new method. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Visible light‐absorbing biocompatible polymers based on L‐lactide and aminosugars: preparation and characterization
Authors: Skotak Maciej , Larsen Gustavo
Published: August 2010

Two series of polymers with low‐molecular‐weight L‐lactide side‐arms were prepared by ring‐opening polymerization using D‐glucosamine and N‐acetyl‐D‐glucosamine as polymer core molecules, and methanesulfonic acid as solvent and catalyst. This simple synthetic route does not rely on the use of organometallic catalysts, and has also proven useful to the authors for chitosan grafting with lactones. NMR spectroscopy reveals a high degree of substitution (>3), and Fourier transform infrared/NMR spectra suggest the existence of three different lactate tautomers likely to be responsible for coloration. These D‐glucosamine‐based polymers also display glass transition temperatures approximately 10 °C above that of the human body, which points to the potential of these lactone‐grafted aminosugars with tunable amphiphilic character in the design of submicrometer‐sized drug delivery vehicles. They are also viewed as interesting hydrophobic chelating agents for catalytic transition metal centers. Copyright © 2010 Society of Chemical Industry
PHF11 is not a major candidate gene for asthma or eczema in Chinese children
Authors: Sy Hing Y. , Chan Iris H.S. , Hon Ellis K.L. , Kong Alice P.S. , Tang Nelson L.S. , Li Chung Y. , Wong Gary W.K. , Waye Mary M.Y. , Lam Christopher W.K. , Chan Juliana C.N. , Leung Ting F.
Published: August 2010

Positional cloning and candidate gene studies in different Caucasian populations identified the gene encoding plant homeodomain zinc finger protein 11 (PHF11) to be associated with asthma and eczema. Microarray analysis also confirmed increased PHF11 expression in type 1 T‐helper lymphocytes. However, such disease associations are unclear in Asian subjects. This case–control genetic association study investigated the relationship between asthma and eczema phenotypes and tagging single‐nucleotide polymorphisms (SNPs) of PHF11 in Hong Kong Chinese children. Three hundred and nineteen asthmatic children and 236 children with eczema were recruited from hospital clinics and 445 children without any history of allergic disease were recruited as controls from local schools and hospitals. Atopy was defined by the presence of allergen‐specific IgE in plasma or positive skin prick tests with wheal ≥3 mm larger than negative control. Lung function of asthmatics was evaluated by pre‐bronchodilator spirometry. Ten PHF11 SNPs were genotyped by multiplex SNaPshot™ assay. Genotyping call rates were 100% for all SNPs, which also followed Hardy–Weinberg equilibrium. These SNPs were tightly linked in one haplotype block (D′ ≥ 0.95 for nearly all SNP pairs). Physician‐diagnosed asthma was weakly associated with PHF11 +20860 and +22818 (P = 0.032 for both). Atopy was also associated with PHF11 +22398 (P = 0.029). However, none of the PHF11 SNPs was associated with eczema diagnosis and plasma total IgE and spirometric parameters in our patients. Our findings do not support PHF11 to be a major candidate gene for asthma, eczema and aeroallergen sensitization in Chinese children. Pediatr. Pulmonol. © 2010 Wiley‐Liss, Inc.
Use of post‐exercise laryngoscopy to evaluate exercise induced dyspnea
Authors: McNally P. , Greally P.
Published: August 2010

We present the case of a child with asthma who continued to have marked exercise induced dyspnea despite appropriate treatment, and in the face of adequate control of all other asthma symptoms. Spirometry showed a marked truncation of inspiratory flow, and laryngoscopy performed immediately after exercise showed laryngomalacia with dynamic, partial inspiratory obstruction. Exercise induced laryngomalacia (EIL) is a rare cause of exercise induced dyspnea which is diagnosed by post exercise flexible laryngoscopy and may require supraglottoplasty. Pediatr Pulmonol. 2010; 45:1037–1039. © 2010 Wiley‐Liss, Inc.
Attenuation of pulmonary hypertension secondary to left ventricular dysfunction in the rat by Rho‐kinase inhibitor fasudil
Authors: Dai Zen‐Kong , Wu Bin‐Nan , Chen I‐Chen , Chai Chee‐Yin , Wu Jiunn‐Ren , Chou Shah‐Hwa , Yeh Jwu‐Lai , Chen Ing‐Jun , Tan Mian‐Shin
Published: August 2010

Pulmonary hypertension (PH) in left ventricular dysfunction is attributable not only to backward failure of the left ventricle, but also to increased pulmonary vascular resistance (PVR) in some patients. Recently, Rho‐kinase has been known as a potent growth stimulator and mediator of vasoconstriction, and Rho‐kinase inhibitors could ameliorate PVR, little is known about the role of Rho‐kinase in left ventricular dysfunction‐induced PH. We utilized the ascending aortic‐banded rat and assessed the effect of Rho‐kinase inhibitor fasudil on the development of PH secondary to left ventricular dysfunction. Subsequently, in rats subjected to aortic banding for 6 weeks, there were increases in mean pulmonary arterial pressure, pulmonary arteriolar medial thickness, active RhoA, Rho‐kinase II, Rho‐kinase activity, endothelial nitric oxide synthase (eNOS) and endothelin‐1(ET‐1) concomitant with decreased levels in NO and cGMP in the lung. Treatment with fasudil at a dose of 30 mg/kg/day from days 1 to 28 or from days 29 to 42 decreased the mean pulmonary arterial pressure by 57% and 56%, right ventricular hypertrophy by 31% and 30%, pulmonary arteriolar medial thickness by 50% and 50%, and pulmonary expression of Rho‐kinase II by 41% and 28%, respectively, as well as augmented pulmonary expression of eNOS by 16% and 31% and NO by 50% and 76%, respectively, when compared with the vehicle controls. In conclusion, these results suggest that inhibition of Rho‐kinase may provide therapeutic potential for preventing and attenuating the development of PH in left ventricular dysfunction. Further translational study in human is needed to substantiate the findings. Pediatr Pulmonol. 2011; 46:45–59. © 2010 Wiley‐Liss, Inc.
The intermembrane space domain of Tim23 is intrinsically disordered with a distinct binding region for presequences
Authors: de la Cruz Laura , Bajaj Rakhi , Becker Stefan , Zweckstetter Markus
Published: August 2010

Proteins targeted to the mitochondrial matrix are translocated through the outer and the inner mitochondrial membranes by two protein complexes, the translocase of the outer membrane (TOM) and one of the translocases of the inner membrane (TIM23). The protein Tim23, the core component of TIM23, consists of an N‐terminal, soluble domain in the intermembrane space (IMS) and a C‐terminal domain that forms the import pore across the inner membrane. Before translocation proceeds, precursor proteins are recognized by the N‐terminal domain of Tim23, Tim23N (residues 1–96). By using NMR spectroscopy, we show that Tim23N is a monomeric protein belonging to the family of intrinsically disordered proteins. Titrations of Tim23N with two presequences revealed a distinct binding region of Tim23N formed by residues 71–84. In a charge‐hydropathy plot containing all soluble domains of TOM and TIM23, Tim23N was found to be the only domain with more than 40 residues in the IMS that is predicted to be intrinsically disordered, suggesting that Tim23N might function as hub in the mitochondrial import machinery protein network.
Evidence for an association between prostate cancer and chromosome 8q24 and 10q11 genetic variants in African American men: The flint men's health study
Authors: Wang Yunfei , Ray Anna M. , Johnson Emilie K. , Zuhlke Kimberly A. , Cooney Kathleen A. , Lange Ethan M.
Published: August 2010

BACKGROUND

Prostate cancer is the most commonly diagnosed non‐skin cancer in men in the United States and the second leading cause of cancer‐related mortality. African American men have substantially increased risk of both being diagnosed and dying from the disease. Recent genome‐wide genetic association studies have identified a number of common single nucleotide genetic polymorphisms (SNPs) that are associated with prostate cancer in men of European descent. Only a small number of studies have evaluated the association between these genetic variants and prostate cancer in African Americans.

METHODS

We used logistic regression models to assess the association between prostate cancer in African American men and 24 SNPs from regions previously reported to be associated with prostate cancer in men of European descent.

RESULTS

We found nominal evidence (P < 0.05) for association between prostate cancer and three chromosome 8q24 (rs6983561, rs16901979, and rs7000448) and two 10q11 (rs7904463 and rs10740051) SNPs.

CONCLUSIONS

We confirm recent reports that 8q24 variants identified to be associated with prostate cancer in men of European descent are also associated with prostate cancer in African Americans. Our report is the first to find evidence of association between SNPs near MSMB and prostate cancer in African Americans. Of note, rs7000448 is in strong linkage disequilibrium with rs10761581 in NCOA4, a SNP that has been implicated to be independently associated, with respect to the widely reported SNP rs10993994 in the nearby gene MSMB, with prostate cancer in men of European descent. Prostate 71:225–231, 2011. © 2010 Wiley‐Liss, Inc.
Targeting prostate cancer angiogenesis through metastasis‐associated protein 1 (MTA1)
Authors: Kai Li , Wang Jun , Ivanovic Marina , Chung Yeon‐Tae , Laskin William B. , Schulze‐Hoepfner Frank , Mirochnik Yelena , Satcher Robert L. , Levenson Anait S.
Published: August 2010

BACKGROUND

Metastasis‐associated protein 1 (MTA1) is overexpressed in many forms of cancer types but its role in prostate cancer (PCa) progression and metastasis has not been explored. In this study, we addressed the functional and biological role of MTA1 in PCa.

METHODS

Gene expression profiling was used to determine MTA1 overexpression during PCa cell–bone interaction. Immunohistochemistry was used to detect MTA1 on tissue microarrays (TMA) and vascular endothelial growth factor (VEGF), CD31, and Ki67 in xenografts. We used retroviral or lentiviral RNAi transduction of PCa cells to establish MTA1 knockdowns. RT‐PCR, Western blot, invasion, and endothelial cell migration assays were used to characterize the cells in vitro. The role of MTA1 in PCa tumorigenesis was evaluated in mouse xenografts.

RESULTS

We identified MTA1 as a component of bone metastasis signature in PCa, which suggested a possible role for MTA1 in PCa progression and metastasis. MTA1 was expressed at higher levels in PCa cell lines than in normal prostate epithelial cells. Silencing MTA1 significantly suppressed the invasion and angiogenic activity of the cells in vitro and delayed tumor formation and development in mouse xenografts. Tumors that express MTA1 had higher proliferative indices, secreted higher levels of VEGF and were more vascularized. Analysis of the human TMA showed positive correlation between MTA1 nuclear localization/staining intensity and PCa aggressiveness.

CONCLUSIONS

MTA1 pro‐angiogenic and pro‐invasive functions create permissive environment for PCa tumor growth and likely support metastasis. Taken together with its predictive values, MTA1 can be utilized both as a prognostic marker and a therapy target in PCa. Prostate 71:268–280, 2011. © 2010 Wiley‐Liss, Inc.
Long‐Term corticosterone treatment induced lobe‐specific pathology in mouse prostate
Authors: Simanainen Ulla , Lampinen Anita , Henneicke Holger , Brennan Tara C. , Heinevetter Uta , Harwood D. Tim , McNamara Keely , Herrmann Markus , Seibel Markus J. , Handelsman David J. , Zhou Hong
Published: August 2010

BACKGROUND

Glucocorticoids influence prostate development and pathology, yet the underlying mechanisms including possible direct glucocorticoid effect on the prostate are not well characterized.

METHODS

We evaluated the expression of the glucocorticoid receptor (GR) together with the effects of supraphysiological glucocorticoid (corticosterone) on mouse prostate morphology and epithelial proliferation. Mature male mice were treated by weekly subdermal implantation of depot pellets containing either 1.5 mg corticosterone or placebo providing steady‐state release for 4 weeks.

RESULTS

Corticosterone treatment significantly increased dorsolateral and anterior prostate weights as well as prostate epithelial cell proliferation while epithelial apoptosis remained low upon corticosterone treatment. Histological analysis of the anterior lobe demonstrated abnormal, highly disorganized luminal epithelium with frequent formation of bridge‐like structures lined by continuous layer of basal cells not observed following placebo treatment. Molecular analysis revealed corticosterone‐induced increase in expression of stromal growth factor Fgf10 which, together with prominent stromal GR expression, suggest that glucocorticoid modify stromal‐to‐epithelial signaling in the mouse prostate. The mitogenic effects were prostate specific and not mediated by systemic effects on testosterone production suggesting that corticosterone effects were primarily mediated via prostate GR expression.

CONCLUSION

These data demonstrate that murine prostate is significantly and directly influenced by corticosterone treatment via aberrant stromal‐to‐epithelial growth factor signaling. Prostate 71:289–297, 2011. © 2010 Wiley‐Liss, Inc.
Epigenetic silencing of SOCS3 identifies a subset of prostate cancer with an aggressive behavior
Authors: Pierconti Francesco , Martini Maurizio , Pinto Francesco , Cenci Tonia , Capodimonti Sara , Calarco Alessandro , Bassi Pier Francesco , Larocca Luigi Maria
Published: August 2010

BACKGROUND

Chronic inflammation and subsequent tissutal alterations may play a key role in prostate carcinogenesis. In this way, molecular alterations of the suppressor of cytokine signaling 3 (SOCS3), one of the most important inhibitory molecule of inflammatory signal transduction circuitries, could contribute to explain the pleiotropic role of interleukin‐6 (IL‐6) in this type of cancer.

METHODS

We analyzed the methylation status and mRNA expression of SOCS3 in 20 benign prostate hyperplasias (BPH) and in 51 prostate cancer specimens. We analyzed the SOCS3 methylation status using methylation‐specific PCR. Hypermethylation was confirmed by sequencing after subcloning. Epigenetic silencing of this gene was also demonstrated by real‐time PCR and by immunohistochemestry. Results and correlation with clinical data were statistically analyzed.

RESULTS

We found that the promoter of SOCS3 was methylated in 39.2% of prostate cancer. On the contrary, all BPH and normal controls had an unmethylated pattern. Real‐time analysis showed that in methylated cases SOCS3 mRNA expression was reduced by three and four folds as compared to BPH and unmethylated cases, respectively. Interestingly, SOCS3 mRNA level was higher in unmethylated prostate cancer than in BPH. The immunohistochemical staining analysis for SOCS 3 confirmed mRNA results. Moreover, methylation of SOCS3 promoter significantly associated with intermediate–high grade Gleason score (P = 0.0007) and with an unfavorable clinical outcome (P = 0.0019).

CONCLUSIONS

Our data suggest that SOCS3 hypermethylation may be involved in the pathogenesis of prostate cancer and could identify a tumor subset with an aggressive behavior. Prostate 71:318–325, 2011. © 2010 Wiley‐Liss, Inc.
How different from random are docking predictions when ranked by scoring functions?
Authors: Feliu Elisenda , Oliva Baldomero
Published: August 2010

Docking algorithms predict the structure of protein–protein interactions. They sample the orientation of two unbound proteins to produce various predictions about their interactions, followed by a scoring step to rank the predictions. We present a statistical assessment of scoring functions used to rank near‐native orientations, applying our statistical analysis to a benchmark dataset of decoys of protein–protein complexes and assessing the statistical significance of the outcome in the Critical Assessment of PRedicted Interactions (CAPRI) scoring experiment. A P value was assigned that depended on the number of near‐native structures in the sampling. We studied the effect of filtering out redundant structures and tested the use of pair‐potentials derived using ZDock and ZRank. Our results show that for many targets, it is not possible to determine when a successful reranking performed by scoring functions results merely from random choice. This analysis reveals that changes should be made in the design of the CAPRI scoring experiment. We propose including the statistical assessment in this experiment either at the preprocessing or the evaluation step. Proteins 2010. © 2010 Wiley‐Liss, Inc.
The repeat domain of the type III effector protein PthA shows a TPR‐like structure and undergoes conformational changes upon DNA interaction
Authors: Murakami Mário Tyago , Sforça Mauricio Luis , Neves Jorge Luiz , Paiva Joice Helena , Domingues Mariane Noronha , Pereira André Luiz Araujo , de Mattos Zeri Ana Carolina , Benedetti Celso Eduardo
Published: August 2010

Many plant pathogenic bacteria rely on effector proteins to suppress defense and manipulate host cell mechanisms to cause disease. The effector protein PthA modulates the host transcriptome to promote citrus canker. PthA possesses unusual protein architecture with an internal region encompassing variable numbers of near‐identical tandem repeats of 34 amino acids termed the repeat domain. This domain mediates protein–protein and protein–DNA interactions, and two polymorphic residues in each repeat unit determine DNA specificity. To gain insights into how the repeat domain promotes protein–protein and protein–DNA contacts, we have solved the structure of a peptide corresponding to 1.5 units of the PthA repeat domain by nuclear magnetic resonance (NMR) and carried out small‐angle X‐ray scattering (SAXS) and spectroscopic studies on the entire 15.5‐repeat domain of PthA2 (RD2). Consistent with secondary structure predictions and circular dichroism data, the NMR structure of the 1.5‐repeat peptide reveals three α‐helices connected by two turns that fold into a tetratricopeptide repeat (TPR)‐like domain. The NMR structure corroborates the theoretical TPR superhelix predicted for RD2, which is also in agreement with the elongated shape of RD2 determined by SAXS. Furthermore, RD2 undergoes conformational changes in a pH‐dependent manner and upon DNA interaction, and shows sequence similarities to pentatricopeptide repeat (PPR), a nucleic acid‐binding motif structurally related to TPR. The results point to a model in which the RD2 structure changes its compactness as it embraces the DNA with the polymorphic diresidues facing the interior of the superhelix oriented toward the nucleotide bases. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Computational studies of the interaction between the HIV‐1 integrase tetramer and the cofactor LEDGF/p75: Insights from molecular dynamics simulations and the Informational spectrum method
Authors: Tintori Cristina , Veljkovic Nevena , Veljkovic Veljko , Botta Maurizio
Published: August 2010

A crystal structure of the integrase binding domain (IBD) of the lens epithelium‐derived growth factor (LEDGF/p75) in complex with the dimer of the HIV‐1 integrase (IN) catalytic core domain (CCD) provides useful information that might help in the understanding of essential protein‐protein contacts in HIV‐1. However, mutagenic studies indicated that interactions between the full‐length proteins were more extensive than the contacts observed in the co‐crystal structure of the isolated domains. On the other hand, the biochemical characterization of the interaction between full‐length IN and LEDGF/p75 has recently proved that LEDGF/p75 promotes IN tetramerization with two LEDGF/p75 IBD molecules bound to the IN tetramer. This experimental evidence suggests that to obtain a complete structural description of the interactions between the two proteins, the full‐length tetrameric structure of IN should be considered. Our aim was to obtain a detailed picture of HIV‐1 IN interactions with cellular co‐factors that was of general interest, particularly for the development of small molecule IN inhibitors, which mimic the IBD of LEDGF/p75. To this end, we performed bioinformatics analyses to identify protein sequence domains involved in long‐range recognition. Subsequently, we applied molecular dynamics techniques to investigate the detailed interactions between the complete tetrameric form of IN and two molecules of the IBD of LEDGF/p75. Our dynamic picture is in agreement with experimental data and, thereby, provides new details of the IN‐LEDGF/p75 interaction. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Protein loop modeling by using fragment assembly and analytical loop closure
Authors: Lee Julian , Lee Dongseon , Park Hahnbeom , Coutsias Evangelos A. , Seok Chaok
Published: August 2010

Protein loops are often involved in important biological functions such as molecular recognition, signal transduction, or enzymatic action. The three dimensional structures of loops can provide essential information for understanding molecular mechanisms behind protein functions. In this article, we develop a novel method for protein loop modeling, where the loop conformations are generated by fragment assembly and analytical loop closure. The fragment assembly method reduces the conformational space drastically, and the analytical loop closure method finds the geometrically consistent loop conformations efficiently. We also derive an analytic formula for the gradient of any analytical function of dihedral angles in the space of closed loops. The gradient can be used to optimize various restraints derived from experiments or databases, for example restraints for preferential interactions between specific residues or for preferred backbone angles. We demonstrate that the current loop modeling method outperforms previous methods that employ residue‐based torsion angle maps or different loop closure strategies when tested on two sets of loop targets of lengths ranging from 4 to 12. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Simulations of carrier confinement in boron δ‐doped diamond devices
Authors: Fiori Alexandre , Pernot Julien , Gheeraert Etienne , Bustarret Etienne
Published: August 2010

Diamond delta‐doped field effect transistors are expected to combine high speed and high power commutation. Critical parameters for the design of a diamond 2D hole gas were determined. The investigated diamond structures were made of an infinite or semi‐infinite diamond crystal with a low boron concentration and of a thin highly boron‐doped 2D diamond layer called the delta‐layer. The carrier density, wave‐function extension, energy spectrum, and band‐edges along the device depth were calculated depending on the delta‐layer thickness, boron concentration, and device geometry. The simulations showed that the thickness of the delta‐layer and the boron doping concentration were the most important parameters, the fraction of holes delocalized out of the delta‐layer decreasing from 90% for an ideal single atomic plane boron doped at 1021 cm−3 down to 30% for a 3 nm thick layer.
Lamé spheroconal harmonics in atoms and molecules
Authors: Méndez‐Fragoso R. , Ley‐Koo E.
Published: August 2010

Spheroconal harmonics are the natural basis for the description of asymmetric‐molecule rotations (Kramers and Ittmann, Zeitschrift für Physik, 1929, 53, 553; Piña, J Mol Str 1999, 493, 159) and also an alternative to the familiar spherical harmonics as the angular part of the Schrödringer equation eigenfunctions for central potentials (Kalnins et al. SIAM J Appl Math 1976, 30, 360). We have dealt with their properties and matrix evaluation in connection with the rotations of asymmetric molecules (Ley‐Koo and Méndez‐Fragoso, Rev Mex Fís 2008, 54, 162) and the construction of a generating function for the complete wave functions of the Hydrogen atom (Ley‐Koo and Góngora, Int J Quantum Chem 2009, 109, 790). For these cases, the spheroconal harmonics are products of Lamé polynomials Λ(χ1)Λ(χ2) in the respective angular coordinates χ1, χ2, with n1 + n2 = ℓ, the angular momentum label. More recently during the investigations of the Hydrogen atom (Méndez‐Fragoso and Ley‐Koo, Int J Quantum Chem. In press) and the rotations of asymmetric molecules (Méndez‐Fragoso and Ley‐Koo, to be submitted), confined in elliptical cones associated with the spheroconal coordinates in which the respective Schrödinger equations are separable, we have recognized the need to use and to construct quasi‐periodic Lamé functions. In fact, the new boundary conditions require that the angular momentum label becomes noninteger ℓ → λ, and the respective Lamé functions become infinite series. This contribution contains details about the evaluation of the polynomial and quasi‐periodic Lamé functions, and their applications in the free particle confined by an elliptical cone with a spherical cap and the harmonic oscillator confined by an elliptical cone. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Mechanical properties of thin polymer films on stiff substrates
Authors: Silbernagl Dorothee , Cappella Brunero
Published: August 2010

Force–displacement curves have been acquired with a commercial atomic force microscope on thin films of poly(n‐butyl methacrylate) on glass substrates in order to examine the so‐called “mechanical double layer” topic, i.e. the influence of the substrate on the mechanical properties of the film in dependence of the film thickness. The hyperbolic fit, a novel semi‐empirical equation introduced in previous articles, has been further corroborated. The interpretation of this equation has been deepened, yielding a quantitative and demonstrative characterization of the mechanical properties of double layers. Provided that the Young's moduli of bulk polymer and substrate are measured from the deformation curves, this mathematical model permits to fit the deformation–force curves on the double layers and to determine the thickness of the polymer films in wide range (0–200 nm). SCANNING 32: 282–293, 2010. © 2010 Wiley Periodicals, Inc.
B-Myb is Critical for Proper DNA Duplication During an Unperturbed S Phase in Mouse Embryonic Stem Cells
Authors: Lorvellec Maëlle , Dumon Stéphanie , Maya-Mendoza Apolinar , Jackson Dean , Frampton Jon , García Paloma
Published: August 2010

A common feature of early embryo cells from the inner cell mass (ICM) and of ESCs is an absolute dependence on an atypical cell cycle in which the G1 phase is shortened to preserve their self-renewing and pluripotent nature. The transcription factor B-Myb has been attributed a role in proliferation, in particular during the G2/M phases of the cell cycle. Intriguingly, B-Myb levels in ICM/ESCs are greater than 100 times compared with those in normal proliferating cells, suggesting a particularly important function for this transcription factor in pluripotent stem cells. B-Myb is essential for embryo development beyond the preimplantation stage, but its role in ICM/ESCs remains unclear. Using a combination of mouse genetics, single DNA fiber analyses and high-resolution three-dimensional (3D) imaging, we demonstrate that B-Myb has no influence on the expression of pluripotency factors, but instead B-Myb ablation leads to stalling of replication forks and superactivation of replication factories that result in disorganization of the replication program and an increase in double-strand breaks. These effects are partly due to aberrant transcriptional regulation of cell cycle proliferation factors, namely c-Myc and FoxM1, which dictate normal S phase progression. We conclude that B-Myb acts crucially during the S phase in ESCs by facilitating proper progression of replication, thereby protecting the cells from genomic damage. Our findings have particular relevance in the light of the potential therapeutic application of ESCs and the need to maintain their genomic integrity.
Efficient Generation of Functional Dopaminergic Neurons from Human Induced Pluripotent Stem Cells Under Defined Conditions
Authors: Swistowski Andrzej , Peng Jun , Liu Qiuyue , Mali Prashant , Rao Mahendra S. , Cheng Linzhao , Zeng Xianmin
Published: August 2010

Human induced pluripotent stem cells (iPSCs) reprogrammed from somatic cells represent a promising unlimited cell source for generating patient-specific cells for biomedical research and personalized medicine. As a first step, critical to clinical applications, we attempted to develop defined culture conditions to expand and differentiate human iPSCs into functional progeny such as dopaminergic neurons for treating or modeling Parkinson's disease (PD). We used a completely defined (xeno-free) system that we previously developed for efficient generation of authentic dopaminergic neurons from human embryonic stem cells (hESCs), and applied it to iPSCs. First, we adapted two human iPSC lines derived from different somatic cell types for the defined expansion medium and showed that the iPSCs grew similarly as hESCs in the same medium regarding pluripotency and genomic stability. Second, by using these two independent adapted iPSC lines, we showed that the process of differentiation into committed neural stem cells (NSCs) and subsequently into dopaminergic neurons was also similar to hESCs. Importantly, iPSC-derived dopaminergic neurons were functional as they survived and improved behavioral deficits in 6-hydroxydopamine-leasioned rats after transplantation. In addition, iPSC-derived NSCs and neurons could be efficiently transduced by a baculoviral vector delivering episomal DNA for future gene function study and disease modeling using iPSCs. We also performed genome-wide microarray comparisons between iPSCs and hESCs, and we derived NSC and dopaminergic neurons. Our data revealed overall similarity and visible differences at a molecular level. Efficient generation of functional dopaminergic neurons under defined conditions will facilitate research and applications using PD patient-specific iPSCs.
Monodisperse α-Fe2O3 Mesoporous Microspheres: One-Step NaCl-Assisted Microwave-Solvothermal Preparation, Size Control and Photocatalytic Property
Authors: Cao Shao-Wen , Zhu Ying-Jie
Published: August 2010

A simple one-step NaCl-assisted microwave-solvothermal method has been developed for the preparation of monodisperse α-Fe2O3 mesoporous microspheres. In this approach, Fe(NO3)3 · 9H2O is used as the iron source, and polyvinylpyrrolidone (PVP) acts as a surfactant in the presence of NaCl in mixed solvents of H2O and ethanol. Under the present experimental conditions, monodisperse α-Fe2O3 mesoporous microspheres can form via oriented attachment of α-Fe2O3 nanocrystals. One of the advantages of this method is that the size of α-Fe2O3 mesoporous microspheres can be adjusted in the range from ca. 170 to ca. 260 nm by changing the experimental parameters. High photocatalytic activities in the degradation of salicylic acid are observed for α-Fe2O3 mesoporous microspheres with different specific surface areas.
Cent dix ans de renouvellements incessants
Authors: Brian Éric
Published: August 2010

Au cours de ses cent dix ans d’existence la Revue de synthèse a connu des périodes différentes chaque fois caractérisées par des prédilections, des actions et des modes de publication particuliers. Au fil de ce long itinéraire, elle a préservé un lieu de référence pour la réflexion historiographique et pour le dialogue entre les sciences. Elle a aussi été un aiguillon pour l’histoire intellectuelle, l’histoire des sciences et de l’ épistémologie. L’article retrace cet itinéraire et en propose des clés utiles aujourd’hui.
Naming without necessity
Authors: Gingras Yves
Published: August 2010

The recent discussions on the label “historical epistemology” provide us with an interesting example of branding of concepts, ideas and methods. Given this recent interest in the meaning of the expression “historical epistemology”, a detailed analysis of its genealogy and context of emergence may provide some conceptual clarification in a discussion that is often confused and curiously silent on the long tradition of sociology of knowledge. This essay also sheds light on the difficulty with the international and interdisciplinary circulation of ideas.
Wu Youxing 吴有兴 et les épidémies pestilentielles
Authors: Übringer Frédéric
Published: August 2010

Devant la Terrible Mordlié des Épidémies Qui Maiquérent La Fin De La Dynastie Ming (1368-1644) Etoe Peu de Rèssite des Traitements Essayés, Wu Youxing (ca 1580-1660), auteur du Wenyilun 温勒 (Traité des épidémies liées à la tiédeur), achevé en 1642, proposa une nouvelle explication étiologique de ces maladies, avec une attitude très critique pour ses prédécesseurs. La réception de l’ouvrage fut contrastée, rencontrant parfois une opposition due à l’audace des conceptions de Wu Youxing et à un écart probable entre les assertions de l’auteur et les échecs sur le terrain.
Administration, savoir technique et reconnaissance impériale
Authors: Zhao Bing
Published: August 2010

Cet article éclaire la carrière de Tang Ying 唐英 (1682-1756), un des premiers administrateurs impériaux à la cour de Chine, à partir de pièces d'archives du Bureau des travaux du Palais de la Maison impériale chargé de la fabrication d'oeuvres d'art à la commande personnelle des empereurs. L'auteur observe la naissance d'une élite et donne à comprendre pourquoi et comment une expertise technique dans le domaine des arts a servi l'ultime dessein politique des empereurs mandchous.
Proteomics of AML1/ETO Target Proteins: AML1–ETO Targets a C/EBP–NM23 Pathway
Authors: Singh Sheo Mohan , Trivedi Arun Kumar , Lochab Savita , Christopeit Maximilian , Hiddemann Wolfgang , Behre Gerhard
Published: August 2010

Introduction

The rational design of targeted therapies for acute myeloid leukemia (AML) requires the discovery of novel protein pathways in the systems biology of a specific AML subtype. We have shown that in the AML subtype with translocation t(8;21), the leukemic fusion protein AML1–ETO inhibits the function of transcription factors PU.1 and C/EBPα via direct protein–protein interaction. In addition, recently using proteomics, we have also shown that the AML subtypes differ in their proteome, interactome, and post-translational modifications.

Methods

We, therefore, hypothesized that the systematic identification of target proteins of AML1–ETO on a global proteome-wide level will lead to novel insights into the systems biology of t(8;21) AML on a post-genomic functional level. Thus, 6 h after inducible expression of AML1–ETO, protein expression changes were identified by two-dimensional gel electrophoresis and subsequent mass spectrometry analysis.

Results

Twenty-eight target proteins of AML1–ETO including prohibitin, NM23, HSP27, and Annexin1 were identified by MALDI-TOF mass spectrometry. AML1–ETO upregulated the differentiation inhibitory factor NM23 protein expression after 6 h, and the NM23 mRNA expression was also elevated in t(8;21) AML patient samples in comparison with normal bone marrow. AML1–ETO inhibited the ability of C/EBP transcription factors to downregulate the NM23 promoter. These data suggest a model in which AML1–ETO inhibits the C/EBP-induced downregulation of the NM23 promoter and thereby increases the protein level of differentiation inhibitory factor NM23.

Conclusions

Proteomic pathway discovery can identify novel functional pathways in AML, such as the AML1–ETO–C/EBP–NM23 pathway, as the main step towards a systems biology and therapy of AML.
DROUGHT TOLERANCE IN MULBERRY (MORUS SPP.): A PHYSIOLOGICAL APPROACH WITH INSIGHTS INTO GROWTH DYNAMICS AND LEAF YIELD PRODUCTION
Authors: GUHA ANIRBAN , RASINENI GIRISH KUMAR , REDDY ATTIPALLI RAMACHANDRA
Published: August 2010

The present study documents critical analysis of drought-induced physiological responses in mulberry (Morus spp.) with insights into growth dynamics and leaf productivity. The study was performed for two years in a two-phase experimental design combining both field (experiment no. 1) and glasshouse (experiment no. 2) observations. In field assays, we surveyed 15 mulberry genotypes under two irrigation regimes: well-watered (20 to 24 irrigations in each growing season) and water-limited (irrigated once in a fortnight in each growing season). The genotypes were assessed for variation in key leaf gas exchange characteristics: net photosynthetic rates (Pn), stomatal conductance of CO2 (gs), transpiration rates (E) and instantaneous water use efficiency (WUEi). Leaf yield/plant was considered to determine the tolerance index (TI). Drought stress severely down-regulated leaf-level physiological variables in the susceptible genotypes resulting in poor leaf yield. However, genotypes S-13 and V-1 performed better in terms of leaf gas exchange and proved their superiority over other genotypes in drought tolerance. Conversely, genotypes DD and Bogurai were highly susceptible to drought. Under glasshouse conditions, the combined leaf gas exchange/chlorophyll a fluorescence measurements further dissected out stomatal and non-stomatal restrictions to Pn. As internal/ambient CO2 ratio (Ci/Ca) decreased concurrently with gs in non-irrigated stands, it appeared that greater stomatal limitation to Pn was associated with decreased photo-assimilation and leaf yield production. Further, higher leaf temperature (TL) (>35 °C) and down-regulation of maximum quantum yield of photosystem II (Fv/Fm) were apparent in the susceptible compared to the tolerant genotypes, which indicated chronic photoinhibition due to photo-inactivation of photosystem II centres in the susceptible genotypes. Drought-induced trade-offs in biomass allocation were also highlighted. Overall, our results suggest that greater rooting vigour and leaf hydration status, minimal stomatal inhibition and stabilized photochemistry might play major roles in maintaining higher Pn and associated gas exchange functions in drought-tolerant mulberry genotypes under water stress conditions. The higher leaf yield production in tolerant than susceptible genotypes can be attributed to minimal plasticity in foliar gas exchange traits and better quantitative growth characteristics under low water regimes.
THE PURITAN PARADIGM OF ENGLISH POLITICS, 1558–1642
Authors: TYACKE NICHOLAS
Published: August 2010

Traditionally puritanism has been treated as a religious phenomenon that only impinged on the world of that ‘secular’ politics to a limited extent and mainly in relation to church reform. Such an approach, however, is to employ a misleadingly narrow definition which ignores the existence of a much more all-embracing puritan political vision traceable from the mid-sixteenth century. First clearly articulated by some of the Marian exiles, this way of thinking interpreted the Bible as a manifesto against tyranny whether in church or state. Under the successive regimes of Elizabeth I, James I, and Charles I, puritans can be found who continued to judge the actions of government by the same biblical criterion, which also helps to explain among other things their prominence in opposing unparliamentary taxation. Puritan ideology itself was transmitted down the generations partly via a complex of family alliances, underpinned by teaching and preaching, and this in turn provided a basis for political organization. Moreover, the undiminished radical potential of puritanism is evident from responses to the assassination of Buckingham in 1628. Given these antecedents the subsequent resort to Civil War appears less surprising than historians often claim.
THE DEVELOPMENT OF POOR RELIEF IN LANCASHIRE, c. 1598–1680
Authors: HEALEY JONATHAN
Published: August 2010

The development of the poor law has formed a key element of recent discussions of ‘state formation’ in early modern England. There are, however, still few local studies of how formal poor relief, stipulated in the great Tudor statutes, was implemented on the ground. This article offers such a study, focusing on Lancashire, an economically marginal county, far from Westminster. It argues that the poor law developed in Lancashire surprisingly quickly in the early seventeenth century, despite the fact that there is almost no evidence of implementation of statutory relief before 1598, and formal relief mechanisms were essentially in place before the Civil War even if the numbers on relief remained small. After a brief hiatus during the conflict, the poor law was quickly revived in the 1650s. The role of the magistracy is emphasized as a crucial driving force, not just in the enforcement of the statutes, but also in setting relief policy. The thousands of petitions to JPs by paupers, parishes, and townships that survive in the county archives suggests that magistrates were crucial players in the ‘politics of the parish’.
STEPHEN GWYNN AND THE FAILURE OF CONSTITUTIONAL NATIONALISM IN IRELAND, 1919–1921
Authors: REID COLIN
Published: August 2010

The Irish Party, the organization which represented the constitutional nationalist demand for home rule for almost fifty years in Westminster, was the most notable victim of the revolution in Ireland, c. 1916–23. Most of the last generation of Westminster-centred home rule MPs played little part in public life following the party's electoral destruction in 1918. This article probes the political thought and actions of one of the most prominent constitutional nationalists who did seek to alter Ireland's direction during the critical years of the war of independence. Stephen Gwynn was a guiding figure behind a number of initiatives to ‘save’ Ireland from the excesses of revolution. Gwynn established the Irish Centre Party in 1919, which later merged with the Irish Dominion League. From the end of 1919, Gwynn became a leading advocate of the Government of Ireland Bill, the legislation that partitioned the island. Revolutionary idealism – and, more concretely, violence – did much to render his reconciliatory efforts impotent. Gwynn's experiences between 1919 and 1921 also, however, reveal the paralysing divisions within constitutional nationalism, which did much to demoralize moderate sentiment further.
THE PARLIAMENTARY COMMISSIONER FOR ADMINISTRATION, THE FOREIGN OFFICE, AND THE SACHSENHAUSEN CASE, 1964–1968
Authors: O'HARA GLEN
Published: August 2010

This communication follows the evolution, reception, and implications of the parliamentary commissioner's critical 1968 report on Foreign Office ‘maladministration’ regarding compensation for British concentration camp inmates. It explores officials' and ministers' attitude to the investigative techniques associated with this new office, as well as their hostile reaction to the publicity and parliamentary controversy to which his work gave rise. It concludes by exploring the wider implications of the case, especially the inherent problems faced by governments seeking closer and more harmonious relationships with the governed.
Craniopharyngioma – a «Geographical Malignant» Tumour
Authors: Stienen  , Cadosch  , Bilz  , Hildebrandt  , Gautschi
Published: August 2010

Das Kraniopharyngeom (KP) ist ein seltener dysontogenetischer Tumor, der seinen Ursprung entweder von versprengten Ductus-craniopharyngeus-Inseln nimmt oder sich metaplastisch von adenohypophysären Parenchymzellen herleitet. Trotz Klassifizierung als WHO-Klasse-I-Tumor kann sich das histologisch benigne KP hierbei zuweilen sehr aggressiv verhalten. Das KP wird meist vor dem 20. Lebensjahr manifest. Patienten klagen oft über Kopfschmerzen, je nach Lokalisation kann auch ein Chiasmasyndrom auftreten. Eine begleitende Hypophysenvorderlappeninsuffizienz manifestiert sich bei Kindern in der Regel in Form einer Wachstumsverzögerung. Zusätzlich kann bei Kompression des Hypophysenhinterlappens ein Diabetes insipidus oder bei Infiltration des Hypothalamus eine Adipositas auftreten. Therapeutisch kommt sowohl die radikale chirurgische Entfernung als auch die Teilresektion mit adjuvanter Radiotherapie zum Einsatz, bei zystischen Tumoren evtl. auch eine stereotaktische Zystendrainage mit ergänzender Bestrahlung. Die Prognose hängt massgebend von der frühzeitigen Diagnosestellung ab.