bluuebunny/crossref_metadata_2025 huggingface dataset:
Strategy for 14C‐labeling of a series of bis(heteroaryl)piperazines
Authors: Arjomandi Omid Khalili , Saemian Nader , Shirvani Gholamhossein , Javaheri Mohsen , Esmailli Kameh
Published: May 2011

Four bis(heteroaryl)piperazines labeled with carbon‐14 in the 2‐position of imidazole moiety were prepared as part of a 4‐step (or 5‐step) sequence from 5‐hydroxymethyl‐2‐mercapto‐1‐benzylimida‐zole‐[2‐14C] as a key synthetic intermediate which has been synthesized from potassium [14C]‐thiocyanate. Copyright © 2011 John Wiley & Sons, Ltd.
Probing the paramagnetic interactions between the unpaired electronic spins of carbon atoms and the nuclear spins of hydrogen molecules with Raman spectroscopy
Authors: Centrone Andrea
Published: May 2011

Carbon materials typically have a high density of unpaired electronic spins but the exact nature of the defect sites that give rise to their magnetic properties are not yet well understood. In this work, the paramagnetic interactions between the unpaired electronic spins of carbon atoms and the nuclear spins of hydrogen molecules were probed with Raman spectroscopy by monitoring the relative population of H2 rotational states. For H2, the symmetries of nuclear spin and rotational wave functions are correlated. Because of the weak interactions between H2 nuclear spins, the transitions between odd and even rotational states are normally hindered. The magnetic field generated by unpaired electronic spins relaxes the selection rules and promotes transitions between H2 rotational levels of different symmetry. This affects the rotational levels' relaxation kinetics toward equilibrium and makes H2 molecules useful to study unpaired electrons in paramagnetic materials. It is suggested that simultaneous electron paramagnetic resonance and Raman measurements on carbon materials interacting with hydrogen molecules could result in a better understanding of the nature of paramagnetic defects in carbon materials, which could have a substantial impact on Li‐ion batteries or for understanding the graphene electronic properties. Copyright © 2011 John Wiley & Sons, Ltd.
New opportunities offered by compact sub‐nanosecond supercontinuum sources in ultra‐broadband multiplex CARS microspectroscopy
Authors: Leproux P. , Couderc V. , de Angelis A. , Okuno M. , Kano H. , Hamaguchi H.
Published: May 2011

We report, to the best of our knowledge, the first turn‐key and compact dual‐output sub‐nanosecond supercontinuum source applicable to ultrabroadband multiplex coherent anti‐Stokes Raman scattering microspectroscopy of biological samples. The light source design and the microspectroscopy setup are described in details. Easy multicolour imaging of Caenorhabditis elegans nematode is operated successfully and discussed. Copyright © 2011 John Wiley & Sons, Ltd.
Reorientation dynamics in liquid alcohols from Raman spectroscopy
Authors: Lin Ke , Hu Naiyin , Zhou Xiaoguo , Liu Shilin , Luo Yi
Published: May 2011

Polarized Raman spectroscopy has been employed to study the reorientational, or more specifically the translational relaxation dynamics, of alcohol molecules in pure liquids and aqueous solutions. It is found from the spectral width measurements that alcohol molecules in pure liquids have typically translational relaxation times on the order of picoseconds, following the order methanol < ethanol < i‐propanol < n‐propanol. Temperature‐dependent measurements show that hydrogen‐bonding (HB) and hydrophobic interactions control the translational motion. The hydrophobic interaction reduces the relaxation time more apparently in view of the CH3 group than the skeleton motion. For alcohol–water mixtures, the increase of water concentration generally slows down the relaxation process in a non‐monotonic behavior. However, the trend stops at a certain point and the motion of alcohol molecules becomes faster when the alcohol concentration further drops. Different mechanisms have been proposed to interpret these observations, which might be helpful to gain deeper insight into the HB networks of alcohols with water. Our study strongly illustrates that Raman spectroscopy can be applied to the study of fast translational motion of molecules in HB systems. Copyright © 2011 John Wiley & Sons, Ltd.
Simultaneous acquisition of all four forms of circular polarization Raman optical activity: results for α‐pinene and lysozyme
Authors: Li Honggang , Nafie Laurence A.
Published: May 2011

A new circularly polarized (CP) Raman spectrometer is described that demonstrates simultaneous acquisition of all four forms of circular polarization Raman optical activity (ROA). The instrument is a design extension of a commercially available back scattering circular polarization (SCP) ROA spectrometer. Circular polarization of the incident beam is introduced with a quarter‐wave plate, and a half‐wave plate alternately positioned in and out of the beam controls the modulation between right circular polarization (RCP) or left circular polarization (LCP) states. Combining this modulation with the simultaneous detection of RCP and LCP scattered Raman radiation allows the measurement of incident circular polarization (ICP), SCP, in‐phase dual circular polarization(DCPI) and out‐of‐phase DCPII‐ROA. In addition, three different forms of backscattered Raman spectra, namely unpolarized, highly polarized, and depolarized Raman spectra, as well as a degree of circularity spectrum are obtained. The performance of the new all‐CP ROA spectrometer is evaluated with neat α‐pinene and aqueous hen lysozyme solution. Copyright © 2011 John Wiley & Sons, Ltd.
A Model for Red Blood Cells in Simulations of Large‐scale Blood Flows
Authors: Melchionna Simone
Published: May 2011

Red blood cells (RBCs) are an essential component of blood. A method to include the particulate nature of blood is introduced here with the goal of studying circulation in large‐scale realistic vessels. The method uses a combination of the Lattice Boltzmann method (LBM) to account for the plasma motion, and a modified molecular dynamics scheme for the cellular motion. Numerical results illustrate the quality of the model in reproducing known rheological properties of blood as much as revealing the effect of RBC structuring on the wall shear stress, with consequences on the development of cardiovascular diseases.

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Three Routes to the Friction Matrix and Their Application to the Coarse‐Graining of Atomic Lattices
Authors: Kauzlarić David , Español Pep , Greiner Andreas , Succi Sauro
Published: May 2011

The calculation of the friction matrix in the coarse‐grained (CG) description of an atomistic system is a crucial issue, in order to properly account for the dissipative effects inherent to any reduced representation of the atomistic dynamics. Within the Mori‐Zwanzig projection operator approach to CG, there are several possibilities for the definition of the friction matrix, depending on the projector that is being used. In this paper, the connection of two of these projectors (Mori's and Zwanzig's) is discussed and the corresponding merits and limitations are analysed. Moreover, three different ways of computing the friction matrix in the Mori's framework are presented, along with a discussion of their mutual connections. By the example of CG centre of mass blob variables in the graphene lattice, it is shown that, even though the three approaches are equivalent from a theoretical viewpoint, they may differ considerably in terms of practical implementation for computer simulation purposes. In the given example, which is representative for atomic lattices, it turns out that a linear regression of the velocity–velocity correlation function, inspired by the Einstein–Helfand approach, is the least error‐prone against disturbances from optical modes.

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Effects of medium and pore‐fluid compressibility on chemical‐dissolution front instability in fluid‐saturated porous media
Authors: Zhao Chongbin , Hobbs Bruce E. , Ord Alison
Published: May 2011

Theoretical analysis and computational simulations have been carried out to investigate how medium and pore‐fluid compressibility affects the chemical‐dissolution front propagation, which is associated with a fully‐coupled nonlinear problem between porosity, pore‐fluid pressure, pore‐fluid density and reactive chemical‐species transport within a deformable and fluid‐saturated porous medium. When the fully‐coupled nonlinear system is in a subcritical state, some analytical solutions have been derived for a special case, in which the ratio of the equilibrium concentration to the solid molar density of the chemical species is approaching zero. To investigate the effect of either medium compressibility or pore‐fluid compressibility on the evolutions of chemical dissolution fronts in supercritical chemical dissolution systems, numerical algorithms and procedures have been also proposed. The related theoretical and numerical results have demonstrated that: (i) not only can pore‐fluid compressibility affect the propagating speeds of chemical dissolution fronts in both subcritical and supercritical systems, but also it can affect the growth and amplitudes of irregular chemical dissolution fronts in supercritical systems; (ii) medium compressibility may have a little influence on the propagating speeds of chemical dissolution fronts, but it can have significant effects on the growth and amplitudes of irregular chemical dissolution fronts in supercritical systems; and (iii) both medium and pore‐fluid compressibility may stabilize irregular chemical‐dissolution‐fronts in supercritical chemical dissolution systems. Copyright © 2011 John Wiley & Sons, Ltd.
The human urothelium consists of multiple clonal units, each maintained by a stem cell
Authors: Gaisa Nadine T , Graham Trevor A , McDonald Stuart AC , Cañadillas‐Lopez Sagrario , Poulsom Richard , Heidenreich Axel , Jakse Gerhard , Tadrous Paul J , Knuechel Ruth , Wright Nicholas A
Published: May 2011

Little is known about the clonal architecture of human urothelium. It is likely that urothelial stem cells reside within the basal epithelial layer, yet lineage tracing from a single stem cell as a means to show the presence of a urothelial stem cell has never been performed. Here, we identify clonally related cell areas within human bladder mucosa in order to visualize epithelial fields maintained by a single founder/stem cell. Sixteen frozen cystectomy specimens were serially sectioned. Patches of cells deficient for the mitochondrially encoded enzyme cytochrome c oxidase (CCO) were identified using dual‐colour enzyme histochemistry. To show that these patches represent clonal proliferations, small CCO‐proficient and ‐deficient areas were individually laser‐capture microdissected and the entire mitochondrial genome (mtDNA) in each area was PCR amplified and sequenced to identify mtDNA mutations. Immunohistochemistry was performed for the different cell layers of the urothelium and adjacent mesenchyme. CCO‐deficient patches could be observed in normal urothelium of all cystectomy specimens. The two‐dimensional length of these negative patches varied from 2–3 cells (about 30 µm) to 4.7 mm. Each cell area within a CCO‐deficient patch contained an identical somatic mtDNA mutation, indicating that the patch was a clonal unit. Patches contained all the mature cell differentiation stages present in the urothelium, suggesting the presence of a stem cell. Our results demonstrate that the normal mucosa of human bladder contains stem cell‐derived clonal units that actively replenish the urothelium during ageing. The size of the clonal unit attributable to each stem cell was broadly distributed, suggesting replacement of one stem cell clone by another. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Haem oxygenase‐1 dictates intrauterine fetal survival in mice via carbon monoxide
Authors: Zenclussen Maria Laura , Casalis Pablo Ariel , El‐Mousleh Tarek , Rebelo Sofia , Langwisch Stefanie , Linzke Nadja , Volk Hans‐Dieter , Fest Stefan , Soares Miguel Parreira , Zenclussen Ana Claudia
Published: May 2011

Pregnancy establishment implies the existence of a highly vascularized and transient organ, the placenta, which ensures oxygen supply to the fetus via haemoproteins. Haem metabolism, including its catabolism by haem oxygenase‐1 (HO‐1), should be of importance in maintaining the homeostasis of haemoproteins and controlling the deleterious effects associated with haem release from maternal or fetal haemoglobins, thus ensuring placental function and fetal development. We demonstrate that HO‐1 expression is essential to promote placental function and fetal development, thus determining the success of pregnancy. Hmox1 deletion in mice has pathological consequences for pregnancy, namely suboptimal placentation followed by intrauterine fetal growth restriction (IUGR) and fetal lethality. These pathological effects can be mimicked by administration of exogenous haem in wild‐type mice. Fetal and maternal HO‐1 is required to prevent post‐implantation fetal loss through a mechanism that acts independently of maternal adaptive immunity and hormones. The protective HO‐1 effects on placentation and fetal growth can be mimicked by the exogenous administration of carbon monoxide (CO), a product of haem catabolism by HO‐1 that restores placentation and fetal growth. In a clinical relevant model of IUGR, CO reduces the levels of free haem in circulation and prevents fetal death. We unravel a novel physiological role for HO‐1/CO in sustaining pregnancy which aids in understanding the biology of pregnancy and reveals a promising therapeutic application in the treatment of pregnancy pathologies. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Neutrophils promote motility of cancer cells via a hyaluronan‐mediated TLR4/PI3K activation loop
Authors: Wu Yan , Zhao Qiyi , Peng Chen , Sun Lin , Li Xue‐Feng , Kuang Dong‐Ming
Published: May 2011

Inflammation is a component of tumour progression mechanisms. Neutrophils are a common inflammatory infiltrate in many tumours, but their regulation and functions in neoplasia are not understood. We recently demonstrated that pro‐inflammatory IL‐17‐producing cells recruited blood neutrophils into the peritumoural stroma of hepatocellular carcinoma by epithelium‐derived CXC chemokines. Here we show that a substantial population of neutrophils accumulates in the peritumoural stroma of hepatocellular, cervical, colorectal, and gastric carcinomas, and that this correlates with metastases in hepatocellular and gastric carcinomas. Exposure of neutrophils to culture supernatants from several types of solid tumour cells (TSN) resulted in sustained survival and pro‐tumourigenic effects of cells. Kinetic experiments reveal that, shortly after exposure to TSN, neutrophils began to provoke activation and then produced significant inflammatory cytokines and expressed more anti‐apoptotic Mcl‐1 but less pro‐apoptotic Bax. These long‐lived neutrophils effectively enhanced the cancer cell motility via a contact‐dependent mechanism; this effect, together with early activation and subsequent longevity of TSN‐exposed neutrophils, could be reversed by blocking the activation of PI3K/Akt signalling in neutrophils. Moreover, we found that hyaluronan (HA) fragments constitute a common factor produced by various tumours that mimics the effect of TSN to induce long‐lived neutrophils and subsequent malignant cell migration. The effects of TSN were inhibited by function blocking interactions between HA and its receptor TLR4 on neutrophils, suggesting that this is a key signalling pathway involved. These results indicate that HA derived from malignant cells educates neutrophils to adopt an activated phenotype, and in that way stimulates the metastasis of malignant cells, which represents a positive regulatory loop between tumours and their stroma during neoplastic progression. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Simultaneously assessing intended and unintended treatment effects of multiple treatment options: a pragmatic “matrix design”
Authors: Rassen Jeremy A. , Solomon Daniel H. , Glynn Robert J. , Schneeweiss Sebastian
Published: May 2011

Purpose

A key aspect of comparative effectiveness research is the assessment of competing treatment options and multiple outcomes rather than a single treatment option and a single benefit or harm. In this commentary, we describe a methodological framework that supports the simultaneous examination of a “matrix” of treatments and outcomes in non‐randomized data.

Methods

We outline the methodological challenges to a matrix‐type study (matrix design). We consider propensity score matching with multiple treatment groups, statistical analysis, and choice of association measure when evaluating multiple outcomes. We also discuss multiple testing, use of high‐dimensional propensity scores for covariate balancing in light of multiple outcomes, and suitability of available software.

Conclusion

The matrix design study methods facilitate examination of the comparative benefits and harms of competing treatment choices, and also provides the input required for calculating the numbers needed to treat and for a broader benefit/harm assessment that weighs endpoints of varying severity. Copyright © 2011 John Wiley & Sons, Ltd.
Analytical treatment of Trivich–Flinn and Shockley–Queisser photovoltaic efficiency limits using polylogarithms
Authors: Green Martin A.
Published: May 2011

Solutions for the Trivich–Flinn and Shockley–Queisser formulations of the limiting efficiency of photovoltaic conversion are derived in terms of polylogarithms. Earlier Trivich–Flinn limits are shown to be zero temperature limits of the Shockley–Queisser approach. The limiting efficiency of an infinite stack of tandem cells was also investigated with an analytically based solution derived, the limit on photovoltaic conversion for a time‐symmetric system, which is compared to the time‐asymmetric limit. Copyright © 2011 John Wiley & Sons, Ltd.
Identification of β2‐microglobulin as a urinary biomarker for chronic allograft nephropathy using proteomic methods
Authors: Johnston Olwyn , Cassidy Hilary , O'Connell Séin , O'Riordan Aisling , Gallagher William , Maguire Patricia B. , Wynne Kieran , Cagney Gerard , Ryan Michael P. , Conlon Peter J. , McMorrow Tara
Published: May 2011

Purpose: Chronic allograft nephropathy (CAN) remains the leading cause of renal graft loss after the first year following renal transplantation. This study aimed to identify novel urinary proteomic profiles, which could distinguish and predict CAN in susceptible individuals.

Experimental design: The study included 34 renal transplant patients with histologically proven CAN and 36 patients with normal renal transplant function. High‐throughput proteomic profiles were generated from urine samples with three different ProteinChip arrays by surface‐enhanced laser‐desorption/ionization time‐of‐flight mass spectrometry (SELDI‐TOF‐MS). Following SELDI, a biomarker pattern software analysis was performed which led to the identification of a novel biomarker pattern that could distinguish patients with CAN from those with normal renal function.

Results: An 11.7 kDa protein identified as β2 microglobulin was the primary protein of this biomarker pattern, distinguishing CAN from control patients (receiver operator characteristic [ROC]=0.996). SELDI‐TOF‐MS comparison of purified β2 microglobulin protein and CAN urine demonstrated identical 11.7 kDa protein peaks. Significantly, higher concentrations of 2 microglobulin were found in the urine of patients with CAN compared with the urine of normal renal function transplant recipients (p<0.001).

Conclusions and clinical relevance: Although further validation in a larger more diverse patient population is required to determine if this β2 microglobulin protein biomarker will provide a potential means of diagnosing CAN by noninvasive methods in a clinical setting, this study clearly shows a capability to stratify control and disease patients.
Multi‐Objective Optimization of Interior Ballistic Performance Using NSGA‐II
Authors: Li Kejing , Zhang Xiaobing
Published: May 2011

This paper investigates an interior ballistic design with equal and unequal web thicknesses of seven‐perforation propellant grains using optimization methods. In order to reveal the influence of the web thickness of the propellant grains on the overall interior ballistic performance, burning seven‐perforation propellant grains with both equal and unequal web thickness is modeled. A currently popular evolution algorithm (EA) is used to compare two charge shapes, and to seek which one could achieve the optimal ballistic performance. Complete optimization of the interior ballistic performance is a complex process in view of the conflicting objectives to be achieved and a solution to such problems is sought by converting them into a single composite objective and using many tedious measurements. In this paper, a true multi‐objective optimization of the interior ballistic charging design is carried out by considering three objectives simultaneously. The non‐dominated sorting genetic algorithm version II (NSGA‐II) is used to solve this multi‐objective optimization problem (MOP). In order to check its implementation, both the conventional optimization algorithm‐hill climbing method (HCM) and NSGA‐II are used to solve the same single objective problem. The NSGA‐II used to capture the full Pareto‐optimal front is capable of identifying the trade‐off among the conflicting objectives thereby providing alternative useful designs for a designer. Furthermore, for seven‐perforation propellant grains, the results of using equal web thickness are compared with those of unequal web thickness, and it is shown that the two charge shapes produce no distinct difference in the interior ballistic performance.
Minimal length and black hole area quantization
Authors: Dvali G. , Gomez C.
Published: May 2011

In this talk we discuss implications of the concept of the minimal length, the Planck length, for black hole physics, and argue, that it naturally leads to quantization of black hole area in Planck units.
On the equivalence of string vacua
Authors: Faraggi A.E.
Published: May 2011

The heterotic‐string models in the free fermionic formulation are among the most realistic string vacua constructed to date, which motivates their detailed exploration. Classification of free fermionic heterotic‐string vacua revealed a duality under exchange of spinor and vector representations of the SO(10) GUT symmetry. The spinor–vector duality was subsequently demonstrated in a Z2 × Z2 × Z2 orbifold, in which the map is realised as exchange of discrete torsions. Analysis of the orbifold partition function shows that the duality map preserves the number of massless twisted states. While the dual vacua are distinct from the point of view of the low energy field theory it is suggested that they are equivalent from the string point of view and may be connected by continuous and discrete transformations.
Warped 5D standard model consistent with EWPT
Authors: Cabrer J. , v. Gersdorff G. , Quirós M.
Published: May 2011

For a 5D Standard Model propagating in an AdS background with an IR localized Higgs, compatibility of bulk KK gauge modes with EWPT yields a phenomenologically unappealing KK spectrum (mKK< 12.5 TeV) and leads to a “little hierarchy problem”. For a bulk Higgs the solution to the hierarchy problem reduces the previous bound only by ∼ $^{1 \over 2}$. As a way out, models with an enhanced bulk gauge symmetry SU(2)R × U(1)B‐L were proposed. In this note we describe a much simpler (5D Standard) Model, where introduction of an enlarged gauge symmetry is no longer required. It is based on a warped gravitational background which departs from AdS at the IR brane and a bulk propagating Higgs. The model is consistent with EWPT for a range of KK masses within the LHC reach.
Recent news and results in the computation of NLO processes with new techniques
Authors: Pittau R.
Published: May 2011

I illustrate new techniques and recently obtained results in the computation of perturbative QCD processes at the NLO accuracy.
Towards classification of SO(10) heterotic string vacua
Authors: Rizos J.
Published: May 2011

We report some recent progress towards classification of phenomenologically appealing heterotic string models in the Free Fermionic Formulation. We focus on a class of Z2× Z2 models with SO(10) space‐time gauge symmetry and study their main phenomenological aspects. We further consider reducing the gauge symmetry to the Pati–Salam gauge group SU(4) × SU(2) L × SU(2)R and impose a series of phenomenological constraints including the existence of gauge symmetry breaking Higgs particles and the elimination of exotic fractionally charged states.
Loop QCD
Authors: Papadopoulos C.G.
Published: May 2011

In this lecture I briefly review the extraordinary developments, over the last few years, of QCD calculations beyond the leading approximation. The new reduction techniques have been paved the way for many calculations, that most people believed impossible before. In particular the OPP method is discussed along with the description of the HELAC‐NLO system. A couple of its applications are briefly presented.
Ingredients of supergravity
Authors: Freedman D. , Van Proeyen A.
Published: May 2011

These notes give a summary of lectures given in Corfu in 2010 on basic ingredients in the study of supergravity. It also summarizes initial chapters of a forthcoming book ‘Supergravity’ by the same authors.
Flavour violating up‐squark decays at LHC
Authors: Eberl H. , Bartl A. , Herrmann B. , Hidaka K. , Majerotto W. , Porod W.
Published: May 2011

We study the effect of squark generation mixing on squark production and decays at the LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the effect can be very large despite the very strong constraints on quark flavour violation (QFV) from experimental data on B mesons. We find that the two lightest up‐type squarks

can have large branching ratios for the decays into

and

at the same time, leading to QFV signals ‘

+ missing‐ET + X′ with a significant rate. The observation of this remarkable signature would provide a powerful test of supersymmetric QFV at LHC. This could have a significant impact on the search for squarks and the determination of the underlying MSSM parameters.
Recent developments in non‐Abelian T‐duality in string theory
Authors: Sfetsos K.
Published: May 2011

Synopsis: We briefly review the essential points of our recent work in non‐Abelian T‐duality. In particular, we show how non‐Abelian T‐duals can effectively describe infinitely high spin sectors of a parent theory and how to implement the transformation in the presence of non‐vanishing Ramond fields in type‐II supergravity.
Labour Market and Economic Impacts of International Working Holiday Temporary Migrants to Australia
Authors: Tan Yan , Lester Laurence H.
Published: May 2011

This paper contributes to the scant literature on the labour market and on the economic consequences of temporary migrants to Australia under the Working Holiday Maker (WHM) programme. Data from two large surveys in 2008, one of WHMs and one of firms that employed WHMs, were used to evaluate the labour market and the economic impacts of WHMs by the application of descriptive analysis and econometric modelling. The analysis demonstrates that the net impact of WHMs is positive for the Australian economy and for employment by increasing the demand for Australian workers because WHMs spend more than they earn while in Australia. We estimate that every 100 WHM arrivals created about five net full‐time equivalent jobs in Australia. Moreover, the supply of WHM labour is of particular importance to employers in regional areas, especially agricultural enterprises who employ them to supply farm labour. More than half of WHM jobs in Australia were in two industries: ‘accommodation’ and ‘agriculture’. Nonetheless, the majority of jobs in which WHMs worked are low skilled, low paid, and in urban areas. In these jobs, WHMs compete with the local low‐skilled labour force and with local youth who seek similar types of jobs. To manage effectively Australia's migration and labour trends and to place the WHM programme in context, it is necessary to understand the increasing demand for short‐term casual labour and the associated lack of supply, especially in regional primary and urban hospitality industry. This paper adds to current understanding by examining these issues in detail. Copyright © 2011 John Wiley & Sons, Ltd.
The microscopic response method: Theory of transport for systems with both topological and thermal disorder
Authors: Zhang MingLiang , Drabold D. A.
Published: May 2011

In this paper, we review and substantially develop the recently proposed “Microscopic Response Method,” which has been devised to compute transport coefficients and especially associated temperature dependence in complex materials. The conductivity and Hall mobility of amorphous semiconductors (ASs) and semiconducting polymers are systematically derived, and shown to be more practical than the Kubo formalism. The effect of a quantized lattice (phonons) on transport coefficients is fully included and then integrated out, providing the primary temperature dependence for the transport coefficients. For higher‐order processes, using a diagrammatic expansion, one can consistently include all important contributions to a given order and directly write out the expressions of transport coefficients for various processes.
Structural and electronic properties of Fe3O4/graphene/Ni(111) junctions
Authors: Dedkov Yu. S. , Generalov A. , Voloshina E. N. , Fonin M.
Published: May 2011

The Fe3O4(111)/graphene/Ni(111) trilayer is proposed to be used as an ideal spin‐filtering sandwich where the half‐metallic properties of magnetite are used. Thin magnetite layers on graphene/Ni(111) were prepared via successive oxidation of a thin iron layer predeposited on graphene/Ni(111) and the formed system was investigated by means of low‐energy electron diffraction and photoelectron spectroscopy. The electronic structure and structural quality of the graphene film sandwiched between two ferromagnetic layers remain unchanged upon magnetite formation as confirmed by experimental data.

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Preparation of the HMF/graphene/FM junction.

(© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Physico‐chemical and functional properties of starch isolated from ginger spent
Authors: Madeneni Madhava Naidu , Faiza Sheema , Ramaswamy Ravi , Guha Manisha , Pullabhatla Srinivas
Published: May 2011

Studies were carried out on starch isolated from ginger spent, obtained after the extraction of oleoresin, to explore the possibility of its use as a food ingredient. AM content was found to be 25.5%. SEM showed the granules were disc‐shaped as well as ovoid with a smooth surface. The average granule size was 22.5 ± 3.5 µ in length and 16.9 ± 4.8 µ in width with thickness of ∼3 µ. Ginger spent starch exhibited a high gelatinization temperature (88°C), peak viscosity (678 Brabender units (BU)) and cold paste viscosity (777 BU). It also possessed low paste clarity and higher freeze–thaw stability. Dynamic rheological properties of ginger spent flour, measured using parallel plate geometry showed that the storage modulus (G′) increased and loss modulus (G″) decreased as a function of frequency. Starch from ginger spent flour with high gelatinization temperature and low in vitro starch digestibility (45%) is suitable to use for development of speciality food formulations.
Effect of storage temperature on starch retrogradation of bread staling
Authors: Aguirre Juan Francisco , Osella Carlos Alberto , Carrara Carlos Roberto , Sánchez Hugo Diego , Buera María del Pilar
Published: May 2011

The objective of the present work was to study the effect of bread storage temperature on starch retrogradation, using water activity measurement and X‐ray diffractometry technique to analyse the changes produced in the crumb firmness such as recrystallization. When storing bread with crust, the crust tends to trap moisture from the crumb, resulting in a dehydration of the crumb with faster staling. For storage temperatures of 25 and 4°C, water activity decreases as a function of storage time whereas at −18°C it is maintained at an almost constant level for 23 days. During storage, the starch molecules are reassociated and generate a new crystalline order which has a typical XRD pattern: the B‐type structure. The peak at 17.4° is indicative of this structure and is related to bread aging. As observed with the recrystallization kinetics, at −18°C only crystal growth may occur, whereas at 25 and 4°C there would be not only growth but also formation of new crystals. At 4°C the rate of starch retrogradation is the highest for the studied conditions.
Interpolation techniques for building a continuous map from discrete wireless sensor network data
Authors: Hammoudeh Mohammad , Newman Robert , Dennett Christopher , Mount Sarah
Published: May 2011

Wireless sensor networks (WSNs) typically gather data at a discrete number of locations. However, it is desirable to be able to design applications and reason about the data in more abstract forms than in points of data. By bestowing the ability to predict inter‐node values upon the network, it is proposed that it will become possible to build applications that are unaware of the concrete reality of sparse data. This interpolation capability is realised as a service of the network. In this paper, the ‘map’ style of presentation has been identified as a suitable sense data visualisation format. Although map generation is essentially a problem of interpolation between points, a new WSN service, called the map generation service, which is based on a Shepard interpolation method, is presented. A modified Shepard method that aims to deal with the special characteristics of WSNs is proposed. It requires small storage, can be localised and integrates the information about the application domain to further reduce the map generation cost and improve the mapping accuracy. Empirical analysis has shown that the map generation service is an accurate, a flexible and an efficient method. Copyright © 2011 John Wiley & Sons, Ltd.
EFFORT: energy‐efficient opportunistic routing technology in wireless sensor networks
Authors: Hung Michael Chien‐Chun , Lin Kate Ching‐Ju , Chou Cheng‐Fu , Hsu Chih‐Cheng
Published: May 2011

The utilization of limited energy in wireless sensor networks (WSNs) is the critical concern, whereas the effectiveness of routing mechanisms substantially influence energy usage. We notice that two common issues in existing specific routing schemes for WSNs are that (i) a path may traverse through a specific set of sensors, draining out their energy quickly and (ii) packet retransmissions over unreliable links may consume energy significantly.

In this paper, we develop an energy‐efficient routing scheme (called EFFORT) to maximize the amount of data gathered in WSNs before the end of network lifetime. By exploiting two natural advantages of opportunistic routing, that is, the path diversity and the improvement of transmission reliability, we propose a new metric that enables each sensor to determine a suitable set of forwarders as well as their relay priorities. We then present EFFORT, a routing protocol that utilizes energy efficiently and prolongs network lifetime based on the proposed routing metric. Simulation results show that EFFORT significantly outperforms other routing protocols. Copyright © 2011 John Wiley & Sons, Ltd.
A 121Sb and 151Eu Mössbauer Spectroscopic Investigation of EuCd2X2 (X = P, As, Sb) and YbCd2Sb2
Authors: Schellenberg Inga , Pfannenschmidt Ulrike , Eul Matthias , Schwickert Christian , Pöttgen Rainer
Published: May 2011

The pnictides EuCd2X2 (X = P, As, Sb) and YbCd2Sb2 were synthesized from the elements or a EuCd2 precursor in tantalum tubes. The samples were characterized by powder X‐ray diffraction. The structure of EuCd2As2 was refined on the basis of single‐crystal X‐ray diffractometer data: CaAl2Si2 type, P$\bar{3}$m1, a = 444.99(9), c = 735.0(1) pm, wR2 = 0.0372, 200 F2 values and 10 variables. The two‐dimensional [Cd2X2] networks consist of edge‐sharing CdX4/4 tetrahedra. The networks are separated and charge‐balanced by the europium and ytterbium atoms. Redetermination of the magnetic properties revealed divalent europium and ytterbium. YbCd2Sb2 is diamagnetic. For the europium compounds only one magnetic phase transition is evident, i.e. TC = 11.6 K for EuCd2P2, TN = 9.5 K for EuCd2As2, and TN = 7.4 K for EuCd2Sb2. 151Eu Mössbauer spectra show full magnetic hyperfine field splitting at 4.2 K. A transferred hyperfine field of 7.1 T is evident in the 4.2 K 121Sb spectrum of EuCd2Sb2.
Seasonal dynamics of soil CO2 efflux in a conventional tilled wheat field of the Loess Plateau, China
Authors: Zhang Hongxing , Zhou Xiaoping , Lu Fei , Pang Junzhu , Feng Zongwei , Liu Wenzhao , Ouyang Zhiyun , Wang Xiaoke
Published: May 2011

An automated chamber system was employed to measure the soil CO2 efflux (SCE) in situ for 2 years in a conventional wheat field of the Loess Plateau, China under semi‐arid conditions. The annual mean SCE values were 2.44 ± 2.52 μmol m−2 s−1 in 2006 and 2.37 ± 2.33 μmol m−2 s−1 in 2007. Distinct seasonality in the SCE was observed, with significant differences occurring among four periods divided by harvesting, tillage and sowing. In the period from tillage to sowing, the mean SCE values were 2.82 and 2.69 times the annual mean values in 2006 and 2007, respectively, and SCE accounted for 39% and 48% of the annual total within 14% and 18% of the days of the years. Although there were significant exponential correlations between the SCE and soil temperature, and significant linear correlations between the SCE and soil moisture for measurements conducted in the periods before tillage and after sowing each year, the SCE from tillage to sowing was significantly beyond the correlation curves. These findings indicated that seasonal variation in the SCE in a conventional field was controlled not only by soil temperature and moisture, but also by tillage practice. The confounding effects of climate and practice on SCE should be considered when developing ways to mitigate soil carbon loss in conventional cropland in semi‐arid regions.
Concentration of Stearidonic Acid in Free Fatty Acid and Fatty Acid Ethyl Ester Forms from Modified Soybean Oil by Winterization
Authors: Vázquez Luis , Akoh Casimir C.
Published: May 2011

The concentration of stearidonic acid (SDA, 18:4 ω‐3) in free fatty acid (FFA) and fatty acid ethyl ester (FAEE) forms by low temperature crystallization (winterization) was studied. For this purpose, modified soybean oil (initial SDA content, ~23%) was transformed into its corresponding FFA and FAEE by chemical hydrolysis and ethanolysis, respectively. In the first study, the FFA and FAEE were used as starting material for winterization and variables such as winterization time, type of solvent, and the oil:solvent ratio were evaluated until optimization of the process was achieved. In the second study, changes in the winterization procedure were introduced to obtain a remarkable improvement on the SDA purity of the final products. Since winterization of FAEE was not efficient due to its low melting points, the second study focused on FFA. The best relationship between SDA purity (59.8%) and SDA yield (82.3%) was attained by performing winterization of FFA with hexane at 10% oil:solvent ratio for 24 h. Scaled‐up processes were also performed to obtain 59 g of FFA (purity 59.6%; yield 82.6%) enriched in SDA. The products obtained can be used as starting materials for the production of functional lipids and for clinical trials.
Nutrition of beef breeder cows in the dry tropics. 1. Effects of nitrogen supplementation and weaning on breeder performance
Authors: Dixon R. M. , Playford C. , Coates D. B.
Published: May 2011

The effects of two dry season management strategies consisting of timing of weaning and/or nitrogen (N) supplementation on the body reserves, nutritional status and reproductive performance were, commencing in the early dry season, examined in Bos indicus × Bos taurus breeder cows (n = 122) grazing native pasture in the seasonally dry tropics. Cows were early-weaned in April in the early dry season or late-weaned in September in the late dry season. The supplement consisted of loose mineral mix which provided on average 14 g N/day, principally as non-protein N. In the early dry season in April 1997 all of the cows had been lactating for 3–5 months, averaged 363 kg (s.d. = 28) conceptus-free liveweight (CF.LW) and 4.7 (s.d. = 0.6) body condition score (9-point scale), and 53% were pregnant. In addition, from April to June 1997 10/26 non-pregnant lactating cows, and 24/31 non-pregnant non-lactating (i.e. early-weaned) cows became pregnant so that 81% of cows were pregnant by June. Predictions of diet from near-infrared spectroscopy of faeces indicated that the forage diet selected during the dry season (April–November) by the cows contained on average 9% (s.d. = 2) non-grass dicotyledonous plants and 4.4% (s.d. = 0.38) crude protein (CP), while DM digestibility was 51.1% (s.d. = 1.3). The diet CP concentration, the ratio of CP to metabolisable energy (ME) in the diet (mean 5.7, s.d. = 0.53, g CP/MJ ME) and faecal N concentration (mean 1.05, s.d. = 0.097, % N) all indicated that unsupplemented cows were deficient in dietary N during the dry season. Microbial CP synthesis in unsupplemented non-lactating cows decreased from 360 to 107 g microbial CP/day, or from 6.5 to 2.4 g microbial CP/MJ ME intake, as the dry season progressed from May to September 1997. Net endogenous N transfer to the rumen of up to 2 g CP/MJ ME apparently occurred from May to August. Microbial CP synthesis was 25% higher (P < 0.001) in lactating than in non-lactating cows. From April to September cow CF.LW was improved by 0.35 kg/day (P < 0.001) by early weaning, and by 0.11 kg/day (P < 0.10) by N supplementation, but there was no interaction (P > 0.10) between these treatments. From April to June 1997 calf LW gain averaged 0.79 kg/day, but from June to September was only 0.10 kg/day in unsupplemented paddocks and 0.13 kg/day in N-supplemented paddocks. Pregnant cows calved from November 1997 to March 1998. During subsequent mating 96% of non-lactating cows, but only 17% of lactating cows became pregnant. During the 1997–98 wet season there was compensatory LW gain of lower CF.LW non-lactating cows but not of lactating cows. In conclusion, weaning early in the dry season had a much greater effect than a non-protein N-based supplement to conserve breeder cow body reserves, and the effects of the two management strategies were additive.
Iodine supplementation to a diet containing Leucaena leucocephala leaf meal: consequences on nutrient metabolism, clinical chemistry and immunity of goats
Authors: Pattanaik Ashok K. , Khan Sardar Ayub , Goswami Tapas K.
Published: May 2011

The present study was aimed at investigating the metabolic effects of iodine supplementation in goats when fed on a diet containing Leucaena leucocephala, intended to create mild iodine deficiency. Two groups of indigenous adult goats were fed on a leucaena leaf meal-based diet without (CON) or with 0.1 mg iodine per day per animal (EXP) for a period of 180 days. Dry matter intake and dry matter digestibility were higher (P < 0.05) in the EXP group. The retention of nitrogen and phosphorus was higher (P < 0.05) in the EXP group. Retention of calcium was also higher (P = 0.082) in the EXP group. The net loss of bodyweight in the CON group (−1.21 kg) was reversed in EXP goats, which showed a net gain (+1.79 kg). The serum metabolic profile reflected a positive influence of iodine supplementation, which also induced greater (P < 0.001) circulating thyroxine concentration. The cell-mediated immune response was higher (P < 0.05) in the EXP group, whereas humoral immunity remained unaltered. The results suggested that supplementation with extra iodine could be used as an effective strategy to counteract functional disorders of the thyroid and associated adverse effects induced in goats by feeding of leucaena leaf meal.
Ruminant enteric methane mitigation: a review
Authors: Cottle D. J. , Nolan J. V. , Wiedemann S. G.
Published: May 2011

In Australia, agriculture is responsible for ~17% of total greenhouse gas emissions with ruminants being the largest single source. However, agriculture is likely to be shielded from the full impact of any future price on carbon. In this review, strategies for reducing ruminant methane output are considered in relation to rumen ecology and biochemistry, animal breeding and management options at an animal, farm, or national level. Nutritional management strategies have the greatest short-term impact. Methanogenic microorganisms remove H2 produced during fermentation of organic matter in the rumen and hind gut. Cost-effective ways to change the microbial ecology to reduce H2 production, to re-partition H2 into products other than methane, or to promote methanotrophic microbes with the ability to oxidise methane still need to be found. Methods of inhibiting methanogens include: use of antibiotics; promoting viruses/bacteriophages; use of feed additives such as fats and oils, or nitrate salts, or dicarboxylic acids; defaunation; and vaccination against methanogens. Methods of enhancing alternative H2 using microbial species include: inoculating with acetogenic species; feeding highly digestible feed components favouring ‘propionate fermentations’; and modifying rumen conditions. Conditions that sustain acetogen populations in kangaroos and termites, for example, are poorly understood but might be extended to ruminants. Mitigation strategies are not in common use in extensive grazing systems but dietary management or use of growth promotants can reduce methane output per unit of product. New, natural compounds that reduce rumen methane output may yet be found. Smaller but more permanent benefits are possible using genetic approaches. The indirect selection criterion, residual feed intake, when measured on ad libitum grain diets, has limited relevance for grazing cattle. There are few published estimates of genetic parameters for feed intake and methane production. Methane-related single nucleotide polymorphisms have yet to be used commercially. As a breeding objective, the use of methane/kg product rather than methane/head is recommended. Indirect selection via feed intake may be more cost-effective than via direct measurement of methane emissions. Life cycle analyses indicate that intensification is likely to reduce total greenhouse gas output but emissions and sequestration from vegetation and soil need to be addressed. Bio-economic modelling suggests most mitigation options are currently not cost-effective.