bluuebunny/crossref_metadata_2025 huggingface dataset:
Monte Carlo analysis of dynamic characteristics and high‐frequency noise performances of nanoscale double‐gate MOSFETs
Authors: Chen Yongbo , Jo Michael , Mohamed Mohamed , Xu Ruimin
Published: March 2013

In this paper, a full‐band Monte Carlo simulator is employed to study the dynamic characteristics and high‐frequency noise performances of a double‐gate (DG) metal–oxide–semiconductor field‐effect transistor (MOSFET) with 30 nm gate length. Admittance parameters (Y parameters) are calculated to characterize the dynamic response of the device. The noise behaviors of the simulated structure are studied on the basis of the spectral densities of the instantaneous current fluctuations at the drain and gate terminals, together with their cross‐correlation. Then the normalized noise parameters (P, R, and C), minimum noise figure (NFmin), and so on are employed to evaluate the noise performances. To show the outstanding radio‐frequency performances of the DG MOSFET, a single‐gate silicon‐on‐insulator MOSFET with the same gate length is also studied for comparison. The results show that the DG structure provides better dynamic characteristics and superior high‐frequency noise performances, owing to its inherent short‐channel effect immunity, better gate control ability, and lower channel noise. Copyright © 2012 John Wiley & Sons, Ltd.
Galleria mellonella hemocytes destruction after infection with Pseudomonas aeruginosa
Authors: Mizerska‐Dudka Magdalena , Andrejko Mariola
Published: March 2013

The influence of infection with an entomopathogenic strain of Pseudomonas aeruginosa on Galleria mellonella hemocytes was investigated. Extensive bacteriaemia developed 18 h after infection. This was correlated with significant changes in morphology, viability and the spreading ability of immunocompetent hemocytes, namely granulocytes and plasmatocytes. Since bacteriaemia developed, membrane blebbing, cytoplasm vacuolization, cell and organelle swelling, and chromatin condensation were observed among others. These features are typical for apoptotic and autophagal cell death. A gradually increasing level of procaspase and its activation as well as lack of DNA degradation were also detected. Propidium iodide and acridine orange staining indicated that hemocytes become dead ultimately. Infection of G. mellonella larvae with P. aeruginosa also caused significant changes in the arrangement of the actin cytoskeleton in the hemocytes, which might be correlated with their restricted spreading ability.
Assessment of the utility of the 2‐µ thulium laser in surgical removal of intracranial meningiomas
Authors: Passacantilli Emiliano , Anichini Giulio , Lapadula Gennaro , Salvati Maurizio , Lenzi Jacopo , Santoro Antonio
Published: March 2013

Background and Objective

Since the 1960s, lasers have been used in neurosurgery for surgical removal of intracranial tumors. Because of its limited penetration (2 mm) through tissues and its wavelength, which is useful in water medium, the 2‐µ thulium laser has been applied primarily in urology. Its features are attractive for application under microscope magnification during neurosurgical procedures. The aim of this study was to evaluate the usefulness of the 2‐µ thulium laser during microsurgical removal of intracranial meningiomas.

Materials and Methods

Twenty patients with a diagnosis of intracranial meningiomas were treated with surgical intervention using a 2‐µ thulium laser together with bipolar forceps, cavitron ultrasonic surgical aspirator (CUSA) and traditional microdissection instruments. Surgical removal was divided in four phases: (1) dissection from the external structures; (2) coagulation and debulking; (3) dissection from the deep structures; and (4) coagulation and removal of the basal implant. During all these steps, we evaluated the percentage of usage of the 2‐µ thulium laser comparing them with bipolar forceps and ultrasonic aspirator and blunt dissection.

Results

Thulium laser was used mainly during phases 2 and 4 for 43% and 48.7% of the total removal, respectively. Although also useful during phases 1 and 3, it was only used for 2.2% and 31.3%, respectively: traditional dissection with scissors and forceps was preferred.

Conclusions

Thulium laser seems to be a useful aid in the surgery of intracranial meningiomas, especially to debulk, shrink, and coagulate the mass and the basal implant. Lasers Surg. Med. 45: 148–154, 2013. © 2013 Wiley Periodicals, Inc.
Buffer‐Stable Chitosan–Polyglutamic Acid Hybrid Nanoparticles for Biomedical Applications
Authors: Malhotra Astha , Zhang Xiaolei , Turkson James , Santra Swadeshmukul
Published: March 2013

In spite of their attractive features, widespread biomedical applications of CS nanoparticles are yet to be realized due to their poor stability in physiological conditions, such as in buffer system at pH 7.4. Buffer‐stable chitosan‐based hybrid NPs (HNPs) are reported and characterized. Buffer stability is achieved by introducing polyglutamic acid to chitosan. The effect of PGA to CS molar ratio and crosslinking on HNP integrity, buffer stability, and biodegradability are studied. Preliminary in vitro studies are carried out to evaluate targeted uptake efficiency of folate conjugated HNPs. Successful demonstration of buffer stability and cancer cell targeting by HNPs achieves important milestones for chitosan‐based nanoparticle technology.

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UV‐Induced Frontal Polymerization of a Pt‐Catalyzed Hydrosilation Reaction
Authors: Sangermano Marco , Marchi Sophie , Ligorio Davide , Meier Patrick , Kornmann Xavier
Published: March 2013

The bis(acetylacetonato)platinum(II) is a common thermal catalyst for the hydrosilation reaction, and it is reported to serve also as a photoactivated catalyst for hydrosilation addition of silanes to alkenes and alkynes. In this paper, it is demonstrated that the UV‐activation of hydrosilation reaction proceeds via a thermal‐frontal mechanism. UV light activates the polymerization on the surface of the sample and, subsequently, the heat released by hydrosilation generates a thermal front, converting the UV‐generated homogeneous catalyst to a Pt0 heterogeneous catalyst. The UV‐induced frontal polymerization mechanism can exhaustively explain the dark‐curing process observed in the UV‐activated hydrosilation reaction.

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Modeling the Transition from Enhanced Oil Recovery to Geologic Carbon Sequestration
Authors: Bandza Alexander J. , Vajjhala Shalini P.
Published: March 2013

Policy debates suggest a future role for geologic carbon sequestration. As geologic sequestration (GS) evolves from enhanced oil recovery operations to an emissions‐mitigation option, regulations must evolve to manage the risks of carbon dioxide (CO2) migration. We develop an engineering‐economic model to understand the key deployment pathways in this transition. Major results reveal that dedicated CO2 storage in aquifers is associated with the greatest net revenues under only a limited number of scenarios. This finding suggests that regulators should anticipate GS operations in reservoirs that were not initially intended as GS operations and, therefore, may have higher leakage rates. Copyright © 2013 John Wiley & Sons, Ltd.
Response of serum and red blood cell folate concentrations to folic acid supplementation depends on methylenetetrahydrofolate reductase C677T genotype: Results from a crossover trial
Authors: Anderson Cheryl A. M. , Beresford Shirley A. A. , McLerran Dale , Lampe Johanna W. , Deeb Samir , Feng Ziding , Motulsky Arno G.
Published: March 2013

Scope

By increasing blood folate concentrations, folic acid supplementation reduces risk for neural tube defect‐affected pregnancies, and lowers homocysteine concentrations. We assessed response of red blood cell (RBC) and serum folate to folic acid supplementation, and examined association of response with the genetic polymorphism C677T of the methylenetetrahydrofolate NAD(P)H (MTHFR) gene.

Methods and results

Randomized, controlled, crossover trial with two folic acid supplement treatment periods and a 30‐week washout period. The primary outcome is blood folate (serum and RBC) concentrations. Volunteers (n = 142) aged 18–69 were randomized to two of three doses (0, 200, and 400 μg) of folic acid for 12 weeks. Serum folate response depended on treatment period with significant responses to 200 μg seen only in the second treatment periods (4.4 ng/mL or 3.4 ng/mL). Additionally, serum folate increased as folic acid dose increased to 400 μg (p < 0.01) and response was greater after the washout period (8.7 ng/mL), than after a 6‐week run‐in (2.3 ng/mL). The differential change attributable to a daily supplement of 400 μg compared to 200 μg was 96.8 ng/mL; while the change attributable to 400 μg compared to 0 μg was 121.4. Increases in RBC folate concentrations with 400 μg occurred within MTHFR gene mutation (C677T); and in the African American group.

Conclusion

Serum folate concentration is responsive to modest increases in folic acid intake. RBC folate increases only with higher additional doses of folic acid supplementation, and this is true for each MTHFR C677T genotype.
Premicellar interaction of PEO–PPO–PEO triblock copolymers with partially hydrophobic alcohols: NMR study
Authors: Kříž Jaroslav , Dybal Jiří
Published: March 2013

The interactions of three alcohols, namely, 2‐butanol (BuOH), 3‐methyl‐2‐butanol (MeBuOH), and 3,3‐dimethyl‐2‐butanol (Me2BuOH) with propylene oxide octamer (PO8) and the copolymers (EO)8(PO)13(EO)8 (L35) and (EO)13(PO)30(EO)13 (L64) in D2O were studied using 13C NMR spectra and relaxations and 1H PFG NMR diffusion measurements. For L64, it was shown that the temperature at which the PO chain starts to change its conformation under dehydration decreases by 6 K for each additional methyl group in the alcohol molecule (i.e. with increasing its hydrophobicity), and the analogous conformation states are attained at temperatures approximately 10 K lower compared using ketonic analogs of the alcohols under the same conditions. Also, the first signs of L64 aggregation, according to the normalized diffusion coefficients, are at temperatures 7, 10, and 13 K lower for BuOH, MeBuOH, and Me2BuOH, respectively. These effects are much weaker for (PO)13 in L35 or nonexistent for (PO)8 in PO8, thus showing the role of cooperativity in dehydration and aggregation processes. According to diffusion measurements, the molar fraction of the alcohol hydrogen bonded to L64 increases with its hydrophobicity and, in an apparent conflict with thermodynamics, with increasing temperature at which also higher NOE can be observed. Strong hydrogen bond interaction, which is in cooperation with hydrophobic interaction, does not preclude the exchange between bound and free states of the alcohol, however. Using 13C transverse relaxation, its correlation time is shown to be of the order of 10 ms. Copyright © 2013 John Wiley & Sons, Ltd.
Long‐term safety, tolerability and efficacy of flexible‐dose fesoterodine in elderly patients with overactive bladder: Open‐label extension of the SOFIA trial
Authors: Wagg Adrian , Khullar Vik , Michel Martin C. , Oelke Matthias , Darekar Amanda , Bitoun Caty Ebel
Published: March 2013

Aims

To assess the long‐term safety, tolerability, and efficacy of flexible‐dose fesoterodine in elderly patients with OAB.

Methods

Patients aged ≥65 years who completed a 12‐week, randomized, double‐blind, placebo‐controlled trial were eligible for the 12‐week, open‐label (OL) extension phase. Patients who received double‐blind placebo started on fesoterodine 4 mg and could increase to 8 mg after 4 or 8 weeks of OL treatment, while fesoterodine‐treated patients continued on their double‐blind dose; only one dose escalation or de‐escalation was permitted. Discontinuations and adverse events (AEs) were monitored, and patients completed 3‐day bladder diaries and patient‐reported outcomes at the beginning and end of the 12‐week OL phase.

Results

Six hundred fifty‐four patients entered the 12‐week OL extension (mean age 72 years; 52% women). AEs were reported by 30.7% and 48.1% of patients who had received double‐blind fesoterodine and placebo, respectively; 1.9% and 9.4%, discontinued due to AEs, respectively. Patients who received double‐blind fesoterodine maintained their efficacy response. After 12 weeks of OL treatment, efficacy outcomes in patients who received double‐blind placebo were similar to those who had received double‐blind fesoterodine. On average, the efficacy response was maintained for the duration of the study.

Conclusions

Fesoterodine was well tolerated and improvements in OAB symptoms and quality of life measures were not diminished with longer‐term treatment of patients aged ≥65 years. Neurourol. Urodynam. 33:106–114, 2014. © 2013 Wiley Periodicals, Inc.
Perfusion deficits in patients with mild traumatic brain injury characterized by dynamic susceptibility contrast MRI
Authors: Liu Wei , Wang Binquan , Wolfowitz Rachel , Yeh Ping‐Hong , Nathan Dominic E. , Graner John , Tang Haiying , Pan Hai , Harper Jamie , Pham Dzung , Oakes Terrence R. , French Louis M. , Riedy Gerard
Published: March 2013

Perfusion deficits in patients with mild traumatic brain injury (TBI) from a military population were characterized by dynamic susceptibility contrast perfusion imaging. Relative cerebral blood flow (rCBF) was calculated by a model‐independent deconvolution approach from the tracer concentration curves following a bolus injection of gadolinium diethylenetriaminepentaacetate (Gd‐DTPA) using both manually and automatically selected arterial input functions (AIFs). Linear regression analysis of the mean values of rCBF from selected regions of interest showed a very good agreement between the two approaches, with a regression coefficient of R = 0.88 and a slope of 0.88. The Bland–Altman plot also illustrated the good agreement between the two approaches, with a mean difference of 0.6 ± 12.4 mL/100 g/min. Voxelwise analysis of rCBF maps from both approaches demonstrated multiple clusters of decreased perfusion (p < 0.01) in the cerebellum, cuneus, cingulate and temporal gyrus in the group with mild TBI relative to the controls. MRI perfusion deficits in the cerebellum and anterior cingulate also correlated (p < 0.01) with neurocognitive results, including the mean reaction time in the Automated Neuropsychological Assessment Metrics and commission error and detection T‐scores in the Continuous Performance Test, as well as neurobehavioral scores in the Post‐traumatic Stress Disorder Checklist–Civilian Version. In conclusion, rCBF calculated using AIFs selected from an automated approach demonstrated a good agreement with the corresponding results using manually selected AIFs. Group analysis of patients with mild TBI from a military population demonstrated scattered perfusion deficits, which showed significant correlations with measures of verbal memory, speed of reaction time and self‐report of stress symptoms. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Complexity and approximability of the maximum flow problem with minimum quantities
Authors: Thielen Clemens , Westphal Stephan
Published: March 2013

We consider the maximum flow problem with minimum quantities (MFPMQ), which is a variant of the maximum flow problem where the flow on each arc in the network is restricted to be either zero or above a given lower bound (a minimum quantity), which may depend on the arc. This problem has recently been shown to be weakly NP ‐complete even on series–parallel graphs. In this article, we provide further complexity and approximability results for MFPMQ and several special cases. We first show that it is strongly NP ‐hard to approximate MFPMQ on general graphs (and even bipartite graphs) within any positive factor. On series–parallel graphs, however, we present a pseudo‐polynomial time dynamic programming algorithm for the problem. We then study the case that the minimum quantity is the same for each arc in the network and show that, under this restriction, the problem is still weakly NP ‐complete on general graphs, but can be solved in strongly polynomial time on series–parallel graphs. On general graphs, we present a
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‐approximation algorithm for this case, where λ denotes the common minimum quantity of all arcs. © 2013 Wiley Periodicals, Inc. NETWORKS, 2013
A posteriori error estimates in quantities of interest for the finite element heterogeneous multiscale method
Authors: Abdulle Assyr , Nonnenmacher Achim
Published: March 2013

We present an “a posteriori” error analysis in quantities of interest for elliptic homogenization problems discretized by the finite element heterogeneous multiscale method. The multiscale method is based on a macro‐to‐micro formulation, where the macroscopic physical problem is discretized in a macroscopic finite element space, and the missing macroscopic data are recovered on‐the‐fly using the solutions of corresponding microscopic problems. We propose a new framework that allows to follow the concept of the (single‐scale) dual‐weighted residual method at the macroscopic level in order to derive a posteriori error estimates in quantities of interests for multiscale problems. Local error indicators, derived in the macroscopic domain, can be used for adaptive goal‐oriented mesh refinement. These error indicators rely only on available macroscopic and microscopic solutions. We further provide a detailed analysis of the data approximation error, including the quadrature errors. Numerical experiments confirm the efficiency of the adaptive method and the effectivity of our error estimates in the quantities of interest. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
Two‐grid methods for semilinear interface problems
Authors: Holst Michael , Szypowski Ryan , Zhu Yunrong
Published: March 2013

In this article, we consider two‐grid finite element methods for solving semilinear interface problems in d space dimensions, for d = 2 or d = 3. We consider semilinear problems with discontinuous diffusion coefficients, which includes problems containing subcritical, critical, and supercritical nonlinearities. We establish basic quasioptimal a priori error estimates for Galerkin approximations. We then design a two‐grid algorithm consisting of a coarse grid solver for the original nonlinear problem, and a fine grid solver for a linearized problem. We analyze the quality of approximations generated by the algorithm and show that the coarse grid may be taken to have much larger elements than the fine grid, and yet one can still obtain approximation quality that is asymptotically as good as solving the original nonlinear problem on the fine mesh. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
An orthogonal subspace minimization method for finding multiple solutions to the defocusing nonlinear Schrödinger equation with symmetry
Authors: Wang Changchun , Zhou Jianxin
Published: March 2013

An orthogonal subspace minimization method is developed for finding multiple (eigen) solutions to the defocusing nonlinear Schrödinger equation with symmetry. As such solutions are unstable, gradient search algorithms are very sensitive to numerical errors, will easily break symmetry, and will lead to unwanted solutions. Instead of enforcing a symmetry by the Haar projection, the authors use the knowledge of previously found solutions to build a support for the minimization search. With this support, numerical errors can be partitioned into two components, sensitive versus insensitive to the negative gradient search. Only the sensitive part is removed by an orthogonal projection. Analysis and numerical examples are presented to illustrate the method. Numerical solutions with some interesting phenomena are captured and visualized by their solution profile and contour plots. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
A morphometric study of the human fetal heart on post‐mortem 3‐tesla magnetic resonance imaging
Authors: Sandaite Inga , De Catte Luc , Moerman Philippe , Gewillig Marc , Fedele Luigi , Deprest Jan , Claus Filip
Published: March 2013

Objective

To report on the feasibility of assessing cardiac structures on post‐mortem 3‐tesla MRI (pmMRI) and to provide morphometric data in fetuses without cardiac abnormalities.

Methods

Retrospective single center study on 3T pmMRI of 39 consecutive fetuses without cardiac abnormalities (13–38 weeks of gestation). Fetal cardiac anatomy was assessed and measurements of cardiac structures were performed on T2‐weighted 3D multiplanar reconstructed images. Linear regression analysis was performed to examine changes of cardiac dimensions during gestation.

Results

The four‐chamber view of the fetal heart could be obtained and the measurements of cardiac chambers and ventricular walls could be performed in all 39 cases. The aorta and the pulmonary artery were visualized and their diameters were measured in 38 (97.4%) fetuses, ductus arteriosus in 32 (82%). All measurements showed strong linear correlation with gestational age. The relationship of the diameters of the pulmonary artery, aorta, and ductus arteriosus remained constant over pregnancy. All these observations are consistent with what is known from prenatal ultrasound.

Conclusions

The present study proves the feasibility of visualizing normal cardiac structures on 3‐tesla pmMRI in fetuses beyond 14 weeks. We provide morphometric data that may enable diagnostic evaluation of cardiac abnormalities on pmMRI. © 2013 John Wiley & Sons, Ltd.
A two‐dimensional proteome map of the aflatoxigenic fungus Aspergillus flavus
Authors: Pechanova Olga , Pechan Tibor , Rodriguez Jose M. , Paul Williams W. , Brown Ashli E.
Published: March 2013

The filamentous fungus Aspergillus flavus is an opportunistic soil‐borne pathogen that produces aflatoxins, the most potent naturally occurring carcinogenic compounds known. This work represents the first gel‐based profiling analysis of A. flavus proteome and establishes a 2D proteome map. Using 2DE and MALDI‐TOF‐MS/MS, we identified 538 mycelial proteins of the aflatoxigenic strain NRRL 3357, the majority of which were functionally annotated as related to various cellular metabolic and biosynthetic processes. Additionally, a few enzymes from the aflatoxin synthesis pathway were also identified.
Tissue proteomics of the low‐molecular weight proteome using an integrated cLC‐ESI‐QTOFMS approach
Authors: Alvarez MeiHwa Tanielle Bench , Shah Dipti Jigar , Thulin Craig D. , Graves Steven W.
Published: March 2013

Analysis of the protein/peptide composition of tissue has provided meaningful insights into tissue biology and even disease mechanisms. However, little has been published regarding top down methods to investigate lower molecular weight (MW) (500–5000 Da) species in tissue. Here, we evaluate a tissue proteomics approach involving tissue homogenization followed by depletion of large proteins and then cLC‐MS (where c stands for capillary) analysis to interrogate the low MW/low abundance tissue proteome. In the development of this method, sheep heart, lung, liver, kidney, and spleen were surveyed to test our ability to observe tissue differences. After categorical tissue differences were demonstrated, a detailed study of this method's reproducibility was undertaken to determine whether or not it is suitable for analyzing more subtle differences in the abundance of small proteins and peptides. Our results suggest that this method should be useful in exploring the low MW proteome of tissues.
Vaginal discharge: recommended management in general practice
Authors: Colver Helen , Malu Manoj
Published: March 2013

Vaginal discharge is usually physiological or caused by infection, and most cases can be treated in primary care. Our Drug review considers the choice of treatments available followed by a review of prescription data.
Assessing the benefits and risks of stopping antiepileptic drugs
Authors: Gallagher Paul , Leach John Paul
Published: March 2013

Our series on stopping drugs provides practical advice on why, when and how to withdraw drug therapy. Here the authors discuss the issues arising from discontinuing antiepileptic medication.
Azilsartan (Edarbi): a new ARB for treating hypertension
Authors: Chaplin Steve , McInnes Gordon
Published: March 2013

Azilsartan medoxomil (Edarbi) is a new angiotensin‐II receptor blocker for use in the treatment of hypertension. In our New products review, Steve Chaplin presents the clinical data relating to its efficacy and adverse events and Professor Gordon McInnes discusses its place in treatment.
Houston's Emerging Exposure between African Americans and Whites: Evidence of Spatial Assimilation or Place Stratification?
Authors: Waren Warren
Published: March 2013

The persistent finding of a racial gap in residential attainment between African Americans and whites has led to a critique, which argues that spatial assimilation theory does not explain the residential segregation of African Americans, even though it explains segregation for other groups. That critique is typically based on analyses of cross‐sectional data, which do not take into account demographic context. In this paper, I examine demographically adjusted exposure scores for educational categories of race and ethnic groups in Houston, Texas, between 1970 and 2000. I find that starting in 1980 higher status African Americans achieved greater spatial assimilation. My findings suggest that analyses that rely on demographically appropriate measures and trend data indicate that spatial assimilation theory is relevant to changes in the residential mobility of African Americans. Copyright © 2013 John Wiley & Sons, Ltd.
Non‐Fermi‐liquid instabilities in non‐centrosymmetric heavy‐fermion CePtSi: A low‐temperature study
Authors: Strydom A. M. , Snyman J. L. , Britz D.
Published: March 2013

CePtSi is a known heavy‐fermion compound with no magnetic ordering. It forms in a tetragonal non‐centrosymmetric crystal structure. Pronounced Kondo features at elevated temperatures originate from magnetic Ce+3 ions. Towards low temperatures coherence develops in the electronic scattering and a Kondo lattice forms below 30 K. At the same temperature scale the electronic specific heat steeply escalates to CP/T ≃ 0.7 J mol−1 K−2. Considerable effort has been devoted in previous studies to find the origin for the observed low‐temperature divergences in thermal properties in CePtSi and in particular for the putative non‐Fermi‐liquid behaviour. To date however, a coherent description of the physics of CePtSi remains to be found. In this work we present low‐temperature results of χ(T), CP(T), and ρ(T). A picture of the low‐temperature nature of this compound is forwarded that is consistent across the thermal properties. We illustrate how a non‐Fermi‐liquid state intervenes between the high‐temperature incoherent Kondo region and Kondo lattice ground state of CePtSi. The non‐Fermi‐liquid region effectively mediates a crossover from the high‐temperature paramagnetic state in CePtSi to its Fermi‐liquid ground state. We argue that magnetic ordering is avoided through a small but intrinsic dissimilarity between nearest‐neighbour Ce atoms.
Static and dynamic susceptibility in the putative ferromagnetic quantum critical system YbNi4P2 probed by 31P NMR
Authors: Sarkar Rajib , Khuntia Panchanan , Spehling Johannes , Krellner Cornelius , Geibel Christoph , Klauss Hans‐Henning , Baenitz Michael
Published: March 2013

The ferromagnetic (FM) quantum critical system YbNi4P2 has been investigated by means of 31P‐NMR. This is a newly discovered heavy fermion system which shows a FM transition at a very low TC = 170 mK. The present reported result is the extension of our previous work published in Ref. 11. 31P NMR results suggest the validity of the Korringa law in the presence of strong FM correlations. 31P NMR spectra have shown the anisotropic nature. The local magnetization derived from our NMR spectra is presented as a function of field at selected temperatures. The obtained spin‐lattice relaxation rate 31(1/T1T) follows a weak power‐law as T−0.75 in a wide field range down to T = 1.8 K. Possible scenarios for this unusual power‐law behavior are discussed. Additionally, 31(1/T1T) is nicely scaled with the observed (C/T)2 ∼ T−0.8 power law in the temperature range 1.8–10 K within the framework of renormalized Landau Fermi Liquid theory.
Disorder in order: silicon versus graphene
Authors: Popescu Mihai , Sava Florinel , Lőrinczi Adam , Velea Alin
Published: March 2013

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The topological transition from order to disorder in crystalline silicon was investigated by a computer simulation procedure. The gradually introduction of topological Wooten–Winer–Weaire defect states makes the crystal change in a more and more disordered assembly of atoms. The characterization of deformation energy around a single defect state is analyzed. The topological transition from graphene structure to an amorphous carbon layer, by introduction of a high number of Stone–Wales defect‐type states was evidenced. The comparison of the disordered structure in tetrahedrally bonded semiconductors (silicon) and a two‐dimensional network based on graphene structure was made.
A comparison of bootstrap approaches for estimating uncertainty of parameters in linear mixed‐effects models
Authors: Thai Hoai‐Thu , Mentré France , Holford Nicholas H.G. , Veyrat‐Follet Christine , Comets Emmanuelle
Published: March 2013

A version of the nonparametric bootstrap, which resamples the entire subjects from original data, called the case bootstrap, has been increasingly used for estimating uncertainty of parameters in mixed‐effects models. It is usually applied to obtain more robust estimates of the parameters and more realistic confidence intervals (CIs). Alternative bootstrap methods, such as residual bootstrap and parametric bootstrap that resample both random effects and residuals, have been proposed to better take into account the hierarchical structure of multi‐level and longitudinal data. However, few studies have been performed to compare these different approaches. In this study, we used simulation to evaluate bootstrap methods proposed for linear mixed‐effect models. We also compared the results obtained by maximum likelihood (ML) and restricted maximum likelihood (REML). Our simulation studies evidenced the good performance of the case bootstrap as well as the bootstraps of both random effects and residuals. On the other hand, the bootstrap methods that resample only the residuals and the bootstraps combining case and residuals performed poorly. REML and ML provided similar bootstrap estimates of uncertainty, but there was slightly more bias and poorer coverage rate for variance parameters with ML in the sparse design. We applied the proposed methods to a real dataset from a study investigating the natural evolution of Parkinson's disease and were able to confirm that the methods provide plausible estimates of uncertainty. Given that most real‐life datasets tend to exhibit heterogeneity in sampling schedules, the residual bootstraps would be expected to perform better than the case bootstrap. Copyright © 2013 John Wiley & Sons, Ltd.
New results in robust functional state estimation using two sliding mode observers in cascade
Authors: Kee Chew Yee , Tan Chee Pin , Ng Kok Yew , Trinh Hieu
Published: March 2013

This paper presents a functional observer scheme using two sliding mode observers in cascade. A coordinate transformation is performed on the system such that existing sliding mode observer theory can be directly applied to achieve functional state estimation. The necessary and sufficient existence conditions for the scheme (in terms of the original system matrices) are also investigated, and they are found to be less stringent than earlier work on functional state estimation using one sliding mode observer; this could have benefits in terms of cost and simplicity. A numerical example verifies the effectiveness of the scheme. Copyright © 2013 John Wiley & Sons, Ltd.
Between–within models for survival analysis
Authors: Sjölander Arvid , Lichtenstein Paul , Larsson Henrik , Pawitan Yudi
Published: March 2013

A popular way to control for confounding in observational studies is to identify clusters of individuals (e.g., twin pairs), such that a large set of potential confounders are constant (shared) within each cluster. By studying the exposure–outcome association within clusters, we are in effect controlling for the whole set of shared confounders. An increasingly popular analysis tool is the between–within (BW) model, which decomposes the exposure–outcome association into a ‘within‐cluster effect’ and a ‘between‐cluster effect’. BW models are relatively common for nonsurvival outcomes and have been studied in the theoretical literature. Although it is straightforward to use BW models for survival outcomes, this has rarely been carried out in practice, and such models have not been studied in the theoretical literature. In this paper, we propose a gamma BW model for survival outcomes. We compare the properties of this model with the more standard stratified Cox regression model and use the proposed model to analyze data from a twin study of obesity and mortality. We find the following: (i) the gamma BW model often produces a more powerful test of the ‘within‐cluster effect’ than stratified Cox regression; and (ii) the gamma BW model is robust against model misspecification, although there are situations where it could give biased estimates. Copyright © 2013 John Wiley & Sons, Ltd.
Robust Synthesis of Gold Cubic Nanoframes through a Combination of Galvanic Replacement, Gold Deposition, and Silver Dealloying
Authors: Wan Dehui , Xia Xiaohu , Wang Yucai , Xia Younan
Published: March 2013

A facile, robust approach to the synthesis of Au cubic nanoframes is described. The synthesis involves three major steps: 1) preparation of Au–Ag alloyed nanocages using a galvanic replacement reaction between Ag nanocubes and HAuCl4; 2) deposition of thin layers of pure Au onto the surfaces of the nanocages by reducing HAuCl4 with ascorbic acid, and; 3) formation of Au cubic nanoframes through a dealloying process with HAuCl4. The key to the formation of Au cubic nanoframes is to coat the surfaces of the Au–Ag nanocages with sufficiently thick layers of Au before they are dealloyed. The Au layer could prevent the skeleton of a nanocage from being fragmented during the dealloying step. The as‐prepared Au cubic nanoframes exhibit tunable localized surface plasmon resonance peaks in the near‐infrared region, but with much lower Ag content as compared with the initial Au–Ag nanocages.
Genomic analysis reveals the biotechnological ability of Enterococcus italicus to produce glutathione
Authors: Borgo Francesca , Carpen Aristodemo , Ferrario Chiara , Iametti Stefania , Fortina Maria Grazia
Published: March 2013

Through the analysis of the recently available genome shotgun sequence of Enterococcus italicus DSM 15952T type strain (Accession PRJNA61487, ID 61487), we found the presence of a gene encoding a bifunctional enzyme, termed γ-GCS-GS or GshF, involved in glutathione production and not influenced by feedback inhibition. The gshF gene exhibited high nucleotide and amino acid sequence similarity to other reported sequences from the Enterococcus genus and was constitutively expressed both in osmotic shock or in common cultural conditions. Several experimental studies concerning the culture medium, physiological stress, cell extract obtainment, and scaling-up showed that in selected conditions E. italicus was able to accumulate up to 250 μM of intracellular glutathione, which represented the main thiol group present into the cells. This is the first report regarding the production of glutathione by E. italicus, a species that could be used as a safe adjunct culture for glutathione-enriched dairy foods.
Aggregation and Phase Separation Phenomenon of Amitriptyline Hydrochloride Under the Influence of Pharmaceutical Excipients
Authors: Rub Malik Abdul , Asiri Abdullah M. , Sheikh Mohmad Shafi , Azum Naved , Khan Anish , Khan Aftab Aslam Parwaz , Rahman Mohammed M. , Kabir‐ud‐Din
Published: March 2013

The interaction between the amphiphilic drug amitriptyline hydrochloride (AMT) and the nonionic surfactants used in drug delivery has been investigated. Herein, we report the micellization behavior of AMT in presence of ethoxylated alkyl phenols in aqueous medium and the clouding phenomenon in the absence and presence of different nonionic surfactants in buffer solution. The values of critical micelle concentration (CMC) of AMT obtained using the conductivity method, decrease as nonionic surfactant concentration increases. With an increase in temperature, the CMC first increases and then decreases. At 303.15 K, the maximum CMC values were obtained with or without nonionic surfactant. The results obtained indicate attractive interactions (synergism) between the two mixing amphiphiles in solution. The experimentally obtained critical micelle concentration (CMC) values are always lower than ideal CMC values. Micellar mole fraction (X1) values, calculated by different proposed models, show the contribution of nonionic surfactant concentration. At a fixed drug concentration (50 mmol kg−1) and pH (=6.7) nonionic surfactants show continuous increase in cloud point (CP). Increase in drug concentration and pH, in the presence of fixed amounts of nonionic surfactant, increases and decreases the CP, respectively.
Ozonation of Anionic and Non‐ionic Surfactants in Aqueous Solutions: Impact on Aquatic Toxicity
Authors: Lechuga Manuela , Fernández‐Arteaga Alejandro , Fernández‐Serrano Mercedes , Jurado Encarnación , Burgos Alejandro , Ríos Francisco
Published: March 2013

The objective of this study was to investigate the influence of ozonation of anionic and non‐ionic surfactants on their aquatic toxicity. Toxicity values of various commercially important anionic and non‐ionic surfactants have been determined using the luminescent bacterium Vibrio fischeri. Surface tension measurements were made to study the interfacial activity. The behavior depends on the chemical structure. Some intermediate ozonation products were found to be more toxic than the base surfactant and others were found to be less. Surfactants with aromatic rings such as linear alkyl benzene sulfonates, or surfactants with glycosidic groups such as alkylpolyglucosides, exhibit a lower toxicity after ozonation. On the other hand, ether groups present in the fatty‐alcohol ethoxylates and ether carboxylic derivative surfactants, and carboxylic acid derivates present in the ether carboxylic derivative surfactants lead to increasing toxicity after ozonation. Surfactants with ether groups probably formed short‐chain polyethoxylated compounds and carboxylic acids, which are possibly responsible for the surface‐tension decrease that promotes the toxicity increase.
Plasticity of Mouse Brain Docosahexaenoic Acid: Modulation by Diet and Age
Authors: Moriguchi Toru , Harauma Akiko , Salem Norman
Published: March 2013

Decreases in brain docosahexaenoic acid (DHA) have been associated with losses in brain function leading to an interest in the conditions which lead to such brain decreases, and such variables as age. Also of relevance would be the rate of repletion of DHA when the n‐3 dietary deficiency is reversed. This experiment describes dietary deficiency in n‐3 fatty acids induced in weanling (3 week) and young adult (7 week) mice. There was an immediate and continuous loss of brain DHA with similar rates in the two age groups. Serum DHA declined more rapidly in younger animals with respect to similarly treated adults. Brain and serum docosapentaenoic acid (DPAn‐6) increased more rapidly and to higher levels in the younger animals. A second experiment determined the rates of normalization of brain fatty acid profiles when alpha‐linolenic acid was added to the diets of n‐3 deficient mice. Brain DHA recovery occurred at a faster rate (half‐time,T1/2= 1.4 weeks) when begun at weaning relative to young adult mice (T1/2= 3.5 weeks). Correspondingly, brain DPAn‐6 recovered faster in the younger animals; the adult group had a half‐time of more than twice that of the 3‐week old group. This study therefore demonstrates that the young adult mouse brain DHA is somewhat plastic and can be partially depleted via a low n‐3 fatty acid diet and subsequently restored when dietary n‐3 fatty acids are repleted. Relevance of these findings for human nutrition is discussed.
Clinical classification of cardiovascular tumors and tumor-like lesions, and its incidences
Authors: Amano Jun , Nakayama Jun , Yoshimura Yasuo , Ikeda Uichi
Published: March 2013

Tumors of the heart and the great vessels are very rare disease, and there are many disorders such as tumors originated from the heart and great vessels, metastatic tumors, and tumor-like lesions which do not fit into the usual concept of tumor or neoplasm; thus, it is very difficult to classify these tumors. We proposed a new classification of cardiovascular tumors for clinical use based on the accumulated biological analyses and clinical data of the reported literatures and our own study as benign tumors, malignant tumors, ectopic hyperplasia/ectopic tumors/others, and tumors of great vessels, with reference to the series of Atlas of tumor pathology of the Armed Forces Institute of Pathology and the recent World Health Organization classification of cardiac tumors issued in 2004. More than 50 disorders have been reported as tumors originated from the cardiovascular system, and various metastatic tumors from nearby organs, distant lesions, and intravascular extension tumors to the heart were reported. Based on the new classification, we reviewed epidemiology and incidence of cardiovascular tumors. Metastatic tumors are more frequent than tumors originated from the heart and great vessels, and cardiac myxoma is the most frequent tumors in all cardiac tumors.
Unique functional roles for class I and class II histone deacetylases in central nervous system development and function
Authors: Morris Michael J. , Monteggia Lisa M.
Published: March 2013

Non‐specific pharmacological inhibition of the histone deacetylase (HDAC) family of enzymes has largely beneficial effects in a variety of diverse contexts including cancer, cognitive function, and neurodegeneration. This review will discuss the role of individual HDAC isoforms in brain function during development and in the adult. Importantly class I and class II HDACs exhibit distinct cellular and subcellular expression patterns and utilize different signaling pathways to influence their substrates. Moreover, dissociable phenotypic outcomes emerge following manipulation of individual HDACs in the brain. To date, pharmacological inhibitors capable of targeting individual HDACs have proven difficult to develop, an obstacle that must be overcome to unlock the substantial clinical promise of manipulating endogenous HDAC isoforms in the central nervous system.
Epigenetic regulation of neural stem cell fate during corticogenesis
Authors: MuhChyi Chai , Juliandi Berry , Matsuda Taito , Nakashima Kinichi
Published: March 2013

The cerebral cortex comprises over three quarters of the brain, and serves as structural basis for the sophisticated perceptual and cognitive functions. It develops from common multipotent neural stem cells (NSCs) that line the neural tube. Development of the NSCs encompasses sequential phases of progenitor expansion, neurogenesis, and gliogenesis along with the progression of developmental stages. Interestingly, NSCs steadfastly march through all of these phases and give rise to specific neural cell types in a temporally defined and highly predictable manner. Herein, we delineate the intrinsic and extrinsic factors that dictate the progression and tempo of NSC differentiation during cerebral cortex development, and how epigenetic modifications contribute to the dynamic properties of NSCs.
Quillen model categories
Authors: Hovey Mark
Published: March 2013

We provide a brief description of the mathematics that led to Daniel Quillen's introduction of model categories, a summary of his seminal work “Homotopical algebra”, and a brief description of some of the developments in the field since.
Modelling potential β-carotene intake and cyanide exposure from consumption of biofortified cassava
Authors: Katz Josh M. , La Frano Michael R. , Winter Carl K. , Burri Betty J.
Published: March 2013

Vitamin A (VA) deficiency causes disability and mortality. Cassava can be crossbred to improve its β-carotene (BC) content; typical white cassava contains negligible amounts of BC. However, cassava contains cyanide and its continued consumption may lead to chronic disability. Our objective was to estimate the risk–benefit of consuming BC-enhanced cassava to increase VA intake. A total of ten American women were fed white and BC-enhanced cassava. BC and cyanide data from the feeding study were combined with African cassava consumption data to model the potential daily BC, VA and cyanide intakes of African women. If BC-enhanced cassava replaced white cassava in the diets, it could theoretically meet recommended VA intakes for the following percentages of individuals from six African countries that consume cassava as a staple crop: Angola (95 %), Central African Republic (95 %), Congo (about 100 %), Ghana (99 %), Mozambique (99 %) and Nigeria (92 %). Cyanide intake after minimal preparation of cassava could be thirteen to thirty-two times the reference dose (RfD), a toxicological exposure reference, but could be completely removed by extensive soaking. This study demonstrates that consumption of BC-enhanced cassava, processed to maintain BC and remove cyanide, theoretically increases VA intakes for African populations and other areas of the world where cassava is a staple crop.
Le mythe fondateur de l’empirisme : le donné épistémologique
Authors: BANDINI AUDE
Published: March 2013

La critique sellarsienne du «mythe du donné» touche en son cœur le projet empiriste fondationnaliste, dont elle entend néanmoins sauvegarder les intuitions épistémologiques et ontologiques saines. Pour ce faire, les difficultés dirimantes soulevées par l’usage de la notion de donné doivent être d’abord clairement identifiées, puis désamorcées. Ceci aboutit à la fois à une redéfinition précautionneuse du donné comme un concept non épistémologique, et à une révision de la conception traditionnelle du rapport entre observation et théorie, connaissance directe et connaissance inférentielle.