bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexible Solar Cells
Authors: Pagliaro Mario , Ciriminna Rosaria , Palmisano Giovanni
Published: October 2008

Thin‐film flexible photovoltaics are paving the way to low‐cost electricity. Organic, inorganic and organic–inorganic solar cells are deposited over flexible substrates by high‐throughput (often roll‐to‐roll printing) technologies to afford lightweight, economic solar modules that can be integrated into, not installed on, various surfaces. Current conversion efficiencies under standard conditions are in the 3–15 % range, but in real applications the overall productivity is high. These new photovoltaic technologies are ready to provide cheap, clean electricity to the 2 billion people who lack access to the grid as well as to energy‐eager companies and families in the developed world facing the increasing costs of electricity generated using fossil fuel resources. This Review focuses on recent achievements in the area of flexible solar cells, highlights the principles behind the main technologies, and discusses future challenges in this area.
Epithelial‐mesenchymal crosstalk in Wolffian duct and fetal testis cord development
Authors: Archambeault Denise R. , Tomaszewski Jessica , Joseph Avenel , Hinton Barry T. , Yao Humphrey Hung‐Chang
Published: October 2008

Interactions between adjacent epithelial and mesenchymal tissues represent a highly conserved mechanism in embryonic organogenesis. In particular, the ability of the mesenchyme to instruct cellular differentiation of the epithelium is a fundamental requirement for the morphogenesis of tubular structures such as those found in the kidneys, lungs, and the developing male reproductive system. Once the tubular structure has formed, it receives signals from the mesenchyme, which can control proliferation, patterning, and differentiation of the epithelium inside the tube. However, the epithelium is not a “silent partner” in this process, and epithelium‐derived factors are often required for proper maintenance of the mesenchymal compartment. Although much emphasis has been placed on the characterization of mesenchymally‐derived signals required for epithelial differentiation, it is important to note that epithelial‐mesenchymal interactions are a two‐way street wherein each compartment requires the presence of the other for proper tubule morphogenesis and function. In this review, we discuss epithelial‐mesenchymal interactions in the processes of Wolffian duct and fetaltestis cord development using the mouse as a model organism and propose inhibin beta A as a conserved mesenchyme‐derived regulator in these two male‐specific tubular structures. genesis 47:40–48, 2009. © 2008 Wiley‐Liss, Inc.
Can NK cells be a therapeutic target in human diseases?
Authors: Chan Christopher J. , Andrews Daniel M. , Smyth Mark J.
Published: October 2008

Our current knowledge of NK‐cell recognition and effector function suggests that it will be possible to design various new NK‐cell‐based immunotherapies against human cancer. The application of NK cells is already showing promise using HLA‐mismatched haematopoietic stem cell transplantation for treatment of haematological malignancies. A better understanding of NK‐cell heterogeneity and function will only broaden the applications for human cancer. Here we review the key developments that will propel this field.
Viral inhibitors of NKG2D ligands: Friends or foes of immune surveillance?
Authors: Jonjić Stipan , Polić Bojan , Krmpotić Astrid
Published: October 2008

NKG2D is a potent activating receptor on NK cells and a co‐stimulatory receptor on CD8+ T cells. Through its ability to recognize a panel of ligands inducible by stress or infection, it plays an important role in the control of viral infections. The viruses have evolved robust mechanisms to counteract NKG2D‐dependent immune response. The functions of these viral inhibitors are well characterized during the early days post‐infection but less so during the chronic viral infection.
Functionally distinct NK‐cell subsets: Developmental origins and biological implications
Authors: Di Santo James P.
Published: October 2008

NK cells were initially identified based on their capacity to destroy susceptible target cells via granule‐mediated cytotoxicity. Subsequently, NK‐cell cytokine production (IFN‐γ, TNF‐α) was shown to be critical in restricting pathogen infection, defining a non‐cytotoxic role for NK cells in host defense. Recently, specialized NK‐cell subsets with biased effector functions have been described in mice and man. This overview will consider the developmental origins and biological implications of this NK‐cell diversification.
Tumor cell recognition by the NK cell activating receptor NKG2D
Authors: Bryceson Yenan T. , Ljunggren Hans‐Gustaf
Published: October 2008

Evidence for increased tumor incidence in NKG2D‐deficient mice has set NKG2D as the first innate immune receptor implicated in immunosurveillance of tumors. In this viewpoint article, we discuss recent genetic insight into NKG2D‐mediated suppression of spontaneous tumor development in the context of NKG2D signaling properties. Moreover, we identify unresolved issues and consider how an understanding of NKG2D‐receptor and ‐ligand biology can facilitate successful therapeutic intervention of human cancer.
NK cells: New issues and challenges
Authors: Colonna Marco
Published: October 2008

NK cells are innate lymphocytes crucial for surveillance against pathogens and tumors. Although the basic mechanisms through which NK cells operate have been established, many questions are still unresolved. Are all NK cells equal or can we identify subsets with distinct developmental origin and function? How do NK cells interact with other components of the immune system, such as DC, effector T cells, and Treg cells to elicit effective immune responses? How do NK cells become tolerant to self and preclude autoimmunity? Finally, can we design novel therapeutic avenues for cancer treatment based on NK cells? The editorial team of the European Journal of Immunology asked the opinion of some of the leading experts in the NK‐cell field regarding the new challenges and opportunities facing this area of research and the thoughts of the experts are presented in this viewpoint series. This introduction to the series brings together some of the novel concepts emerging from the experts' discussions.
Stereoselective Synthesis of Chiral 2,3‐Disubstituted 2,3‐Dihydro‐4(1H)‐pyridones
Authors: Etayo Pablo , Badorrey Ramón , Díaz‐de‐Villegas María D. , Gálvez José A.
Published: October 2008

The alkylation at C‐3 of the easily accessible (R)‐2‐[(S)‐1,2‐bis(benzyloxy)ethyl]‐1‐[(S)‐1‐phenylethyl]‐2,3‐dihydro‐4(1H)‐pyridone with different electrophiles took place with totaltransdiastereoselectivity to afford the corresponding (2R,3S)‐2,3‐disubstituted 2,3‐dihydro‐4(1H)‐pyridones in enantiomerically pure form. The configuration at C‐3 can be inverted by deprotonation and subsequent reprotonation to yield the corresponding (2R,3R)‐2,3‐disubstituted 2,3‐dihydro‐4(1H)‐pyridones in a highly diastereoselective manner.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Thiols in Ugi‐ and Passerini–Smiles‐Type Couplings
Authors: Barthelon Anaëlle , El Kaïm Laurent , Gizolme Marie , Grimaud Laurence
Published: October 2008

The use of the Smiles rearrangement in Ugi‐type couplings with aromatic mercaptans allows for the straightforward, multicomponent formation of α‐arylamino thiocarboxamides. The scope of this new four‐component coupling is further broadened with the use of heterocyclic mercapto derivatives that afford thioamides of high biological interest in one step. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Thermodynamic, Equilibrium and Kinetic Study of the Biosorption of Basic Blue 41 using Bacillus maceran
Authors: Atar N. , Olgun A. , Çolak F.
Published: October 2008

Thermodynamic, kinetic and equilibrium studies during the biosorption of Basic blue 41(BB 41) from aqueous solution using Bacillus macerans were carried out with a focus on pH, contact time, temperature, biomass dosage and initial dye concentration. The maximum adsorption capacity was found to be 89.2 mg/g under optimal conditions of pH (10.0) and temperature (25 °C). The biosorption rates obtained were consistent with the pseudo‐second order kinetic models. The equilibrium data were analyzed using linearized forms of Langmuir and Freundlich isotherms, and the Langmuir isotherm was found to provide the best correlation of the experimental data for the biosorption of BB 41. The equilibrium time for the removal of BB  41 by the biomass was attained within 90 min. Thermodynamic parameters such as free energy (<$>\Delta G<$>), enthalpy (<$>\Delta H<$>), and entropy (<$>\Delta S<$>) were also calculated. The results indicate that biosorption is spontaneous and exothermic in nature. The negative value of entropy confirms the decreased randomness at the solid‐liquid interface during the adsorption of BB 41 onto Bacillus macerans.
A polygenic model for integration of linkage and pathway information
Authors: Lebrec J.J.P. , Nishchenko I. , van der Wijk H.J. , Huizinga T.W. , van Houwelingen H.C.
Published: October 2008

We introduce an approximate model for linkage curves which accommodates the polygenic structure of complex diseases and accounts for the simultaneous action of closely located genes. The model is extended so that information on biological pathways can be integrated. Using data on rheumatoid arthritis, we describe some of the many applications which the model allows: it can be used to test for residual linkage in the presence of already established loci, to derive a global test for linkage, to test for the relevance of a gene list in terms of linkage and to help in candidate gene prioritization by integration of gene‐pathway annotation data. Genet. Epidemiol. 2009. © 2008 Wiley‐Liss, Inc.
The impact of newly identified loci on coronary heart disease, stroke and total mortality in the MORGAM prospective cohorts
Authors: Karvanen Juha , Silander Kaisa , Kee Frank , Tiret Laurence , Salomaa Veikko , Kuulasmaa Kari , Wiklund Per‐Gunnar , Virtamo Jarmo , Saarela Olli , Perret Claire , Perola Markus , Peltonen Leena , Cambien Francois , Erdmann Jeanette , Samani Nilesh J. , Schunkert Heribert , Evans Alun
Published: October 2008

Recently, genome wide association studies (GWAS) have identified a number of single nucleotide polymorphisms (SNPs) as being associated with coronary heart disease (CHD). We estimated the effect of these SNPs on incident CHD, stroke and total mortality in the prospective cohorts of the MORGAM Project. We studied cohorts from Finland, Sweden, France and Northern Ireland (total N=33,282, including 1,436 incident CHD events and 571 incident stroke events). The lead SNPs at seven loci identified thus far and additional SNPs (in total 42) were genotyped using a case‐cohort design. We estimated the effect of the SNPs on disease history at baseline, disease events during follow‐up and classic risk factors. Multiple testing was taken into account using false discovery rate (FDR) analysis. SNP rs1333049 on chromosome 9p21.3 was associated with both CHD and stroke (HR=1.20, 95% CI 1.08–1.34 for incident CHD events and 1.15, 0.99–1.34 for incident stroke). SNP rs11670734 (19q12) was associated with total mortality and stroke. SNP rs2146807 (10q11.21) showed some association with the fatality of acute coronary event. SNP rs2943634 (2q36.3) was associated with high density lipoprotein (HDL) cholesterol and SNPs rs599839, rs4970834 (1p13.3) and rs17228212 (15q22.23) were associated with non‐HDL cholesterol. SNPs rs2943634 (2q36.3) and rs12525353 (6q25.1) were associated with blood pressure. These findings underline the need for replication studies in prospective settings and confirm the candidacy of several SNPs that may play a role in the etiology of cardiovascular disease. Genet. Epidemiol. 2009. © 2008 Wiley‐Liss, Inc.
Understanding the extent of interactions between groundwater and surface water through major ion chemistry and multivariate statistical techniques
Authors: Kumar Manish , Ramanathan Al. , Keshari A. K.
Published: October 2008

The present work examines the possible use of major ion chemistry and multivariate statistical techniques as a rapid and relatively cost‐effective method of identifying the extent of groundwater and surface water (GW–SW) interaction in an urban setting. The original hydrogeochemical dataset consists of groundwater (n = 114), stream water (n = 42) and drain water (n = 24) samples, collected twice in a year for the pre‐ and post‐monsoon seasons, for three successive years along an 8 km reach of the Delhi segment of River Yamuna, India. The dynamic and similar seasonal changes of hydro‐geochemical facies and major ion trends of river, drain and groundwater samples indicate the existence of an empirical relationship between GW and SW. Results of both R‐ and Q‐mode factor and cluster analyses highlight multi‐scale control of the fluid exchange distributions, with distinct seasonal alteration in mode and extent of GW–SW interaction, namely, the influence of the mixing zones between urban river and groundwater and the pattern of groundwater flow through the river bed. Hierarchical cluster analysis (HCA) of sampling locations efficiently illustrates different groups that comprise samples severely influenced by contaminated surface water downstream and the upstream fresh water samples. These results substantiate the strong exchange processes between GW and SW all along the stretch. The study shows that the combination of an empirical and statistical relationship between different ionic species and sampling locations can provide greater confidence in identifying the extent of GW–SW interaction/exchange processes. Copyright © 2008 John Wiley & Sons, Ltd.
Irrigation intervention: a strategy for conserving biodiversity and improving food security in Royal Chitwan National Park buffer zone, Nepal
Authors: Adhikari Keshav R. , Tan Yih‐Chi , Lai Jihn‐Sung , Pant Dhruba
Published: October 2008

Technical interventions have not always led to expected outcomes when attempting to achieve a balanced growth between natural resource development and food production, particularly in the context of Third World countries. In Royal Chitwan National Park (RCNP) buffer zone, Nepal, farmers' perceptions were used to evaluate how irrigation resource development and the method of water sharing have increased household food security and reduced pressure on natural resources of the park. The findings indicate that with some variations between communities, increased water availability and reliability through irrigation development have improved crop diversity, cropping intensity, food sufficiency, and economic return to farmers. Community attributes such as leadership and dynamics were, among others, the decisive factors that determined the degree of success of the government development intervention programme in the buffer zone. Small landholders and low‐income groups in dry areas perceived that they received greater benefits from micro‐groundwater pumping schemes. However, many rural poor inhabitants in the area still lack access to these resource opportunities. We observed that Park and People, a government programme, successfully improved public relations and helped create awareness in this buffer zone. However, grievances persist among other water user groups in the upstream part of the Rapti River where a water‐sharing mechanism needs to be defined between water user associations for crop production and maintenance of biodiversity of the national park. Copyright © 2008 John Wiley & Sons, Ltd.
Multiphoton tissue imaging using high‐NA microendoscopes and flexible scan heads for clinical studies and small animal research
Authors: König Karsten , Weinigel Martin , Hoppert Daniel , Bückle Reiner , Schubert Harald , Köhler Martin J. , Kaatz Martin , Elsner Peter
Published: October 2008

Multiphoton tomographs based on femtosecond laser and GRIN lens technology in combination with flexible scan heads have been developed for clinical high‐resolution tissue imaging and small animal research. The novel tissue tomograph possesses a 0.5 m long flexible mirror arm in combination with piezodriven focusing optics and multiple single photon counting PMT detectors. The photodetectors are in particular useful to obtain information on the extracellular matrix by the simultaneous measurement of the two‐photon autofluorescence of elastin as well as the second harmonic generation of collagen. A major application is the in vivo determination of the skin age index. The rigid two‐photon microendoscope with a high numerical aperture of 0.8 is based on a combination of silver‐doped 1.0 mm rod‐shaped GRIN lens with a hemispheric front optics. It was used in combination with the multiphoton tomograph for clinical studies as well as for inner organ and eye imaging of small animals. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A compact, multidimensional spectrofluorometer exploiting supercontinuum generation
Authors: Manning Hugh B. , Kennedy Gordon T. , Owen Dylan M. , Grant David M. , Magee Anthony I. , Neil Mark A. A. , Itoh Yoshifumi , Dunsby Chris , French Paul M.W.
Published: October 2008

We report a novel, compact and automated multidimensional spectrofluorometer that exploits a fibre‐laser‐pumped ultrafast supercontinuum source to provide resolution with respect to intensity, excitation and emission wavelength, decay time and polarisation. This instrument has been applied to study the photophysics of the phase‐sensitive membrane probe di‐4‐ANEPPDHQ and to characterise protein‐protein interactions via Förster resonance energy transfer. It can be applied toin situmeasurements via a fibre‐optic probe in medical and other contexts and is demonstrated here to provide a comprehensive characterisation of tissue autofluorescence. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Three‐dimensional (3D) backward and forward second harmonic generation (SHG) microscopy of biological tissues
Authors: Bianchini Paolo , Diaspro Alberto
Published: October 2008

In this work we aim to show how it is possible to exploit the second harmonic generation (SHG) signal for producing multimodal microscopic images of biological tissues. SHG microscopy constitutes an important tool for high‐resolution, high‐contrast, three‐dimensional studies of live cell and tissue architectures. The physical origins of SHG within these tissues are addressed and reported in a comprehensive image gallery. Although SHG is a coherent process, the multiple scattering of tissue samples determines the ability to acquire signal in both backward and forward direction. We discuss here some key elements related to the backward and forward SHG signal in terms of acquisition architecture and related microscopic imaging. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Engineering a reversible, high‐affinity system for efficient protein purification based on the cohesin–dockerin interaction
Authors: Karpol Alon , Kantorovich Lia , Demishtein Alik , Barak Yoav , Morag Ely , Lamed Raphael , Bayer Edward A.
Published: October 2008

Efficient degradation of cellulose by the anaerobic thermophilic bacterium, Clostridium thermocellum, is carried out by the multi‐enzyme cellulosome complex. The enzymes on the complex are attached in a calcium‐dependent manner via their dockerin (Doc) module to a cohesin (Coh) module of the cellulosomal scaffoldin subunit. In this study, we have optimized the Coh–Doc interaction for the purpose of protein affinity purification. A C. thermocellum Coh module was thus fused to a carbohydrate‐binding module, and the resultant fusion protein was applied directly onto beaded cellulose, thereby serving as a non‐covalent “activation” procedure. A complementary Doc module was then fused to a model protein target: xylanase T‐6 from Geobacillus stearothermophilus. However, the binding to the immobilized Coh was only partially reversible upon treatment with EDTA, and only negligible amounts of the target protein were eluted from the affinity column. In order to improve protein elution, a series of truncated Docs were designed in which the calcium‐coordinating function was impaired without appreciably affecting high‐affinity binding to Coh. A shortened Doc of only 48 residues was sufficient to function as an effective affinity tag, and highly purified target protein was achieved directly from crude cell extracts in a single step with near‐quantitative recovery of the target protein. Effective EDTA‐mediated elution of the sequestered protein from the column was the key step of the procedure. The affinity column was reusable and maintained very high levels of capacity upon repeated rounds of loading and elution. Reusable Coh–Doc affinity columns thus provide an efficient and attractive approach for purifying proteins in high yield by modifying the calcium‐binding loop of the Doc module. Copyright © 2008 John Wiley & Sons, Ltd.
The effects of focal articular defects on cartilage contact mechanics
Authors: Gratz Kenneth R. , Wong Benjamin L. , Bae Won C. , Sah Robert L.
Published: October 2008

Focal damage to articular cartilage is common in arthroscopy patients, and may contribute to progressive tissue degeneration by altering the local mechanical environment. The effects of a focal defect, which may be oriented at various orientations relative to the subchondral bone, on the dynamics of cartilage contact and deformation are unclear. The objective of this study was to elucidate the effect of experimental full thickness focal defects, oriented at 80° or 100° relative to the subchondral bone, on intratissue strain and surface sliding of opposing cartilage surfaces during compression and stress relaxation. Pairs of intact bovine osteochondral blocks were compressed uniaxially by 20%, and allowed to stress relax. Tissue deformation was recorded by video microscopy. A full‐thickness defect (with either 80° or 100° edges) was created in one block from each pair. Blocks were allowed to reswell and retested. Defect edges were then recut with the opposite orientation, allowed to reswell, and retested again. Stained nuclei were tracked by digital image correlation and used to quantify cartilage strains and surface sliding. The results indicated that loading of intact samples caused axial strain magnitudes that decreased with depth and relatively little sliding. With loading of samples containing defects, strain magnitudes were elevated in cartilage adjacent to, and opposing, defects. For samples with edge orientations of 100°, sliding magnitudes were increased over surfaces adjacent to defects. These local mechanical changes due to full‐thickness articular cartilage defects may contribute to altered chondrocyte metabolism, tissue damage, or accelerated wear. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 584–592, 2009
Noninvasive monitoring of elevated intramuscular pressure in a model compartment syndrome via quantitative fascial motion
Authors: Lynch John E. , Lynch John K. , Cole Steven L. , Carter Jonathan A. , Hargens Alan R.
Published: October 2008

Compartment syndromes, conditions of elevated intramuscular pressure (IMP) resulting from trauma or chronic overuse, frequently require invasive IMP monitoring for accurate diagnosis. Our objective was to test a noninvasive ultrasound technique for estimating IMP based on fascial displacement waveforms from arterial blood pressure pulses. IMP was increased in the legs of 23 healthy adult subjects up to 80 mmHg using two blood pressure cuffs covering the region from the knee to the ankle. Receiver operator characteristic curves and recursive partitioning were used to determine the sensitivity and specificity of diagnosing elevated IMP using fascial displacement. For one curve, in which several ultrasonic measurement parameters were used along with subject body mass index and blood pressure, the sensitivity and specificity for diagnosing normal IMP (below 30 mmHg) from elevated IMP (30 mmHg and up) was 0.61 and 0.94, respectively. Recursive partitioning, in which IMP was divided into three ranges (normal <30 mmHg, midrange of 30–40 mmHg, and elevated ≥50 mmHg), resulted in improved diagnostic sensitivity (0.77) with almost no change in specificity (0.93). © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 489–494, 2009
Interactions between plants in intercropped maize and common bean
Authors: Dawo Mohamed I , Wilkinson J Michael , Pilbeam David J
Published: October 2008

BACKGROUND: Intercropping maize (Zea mays L.) with common bean (Phaseolus vulgaris L.) can give silage yields that are as high as with monocropped maize, but with more crude protein. Interactions between maize and common bean intercropped in the UK were assessed at a range of plant densities (maize 100 000, 75 000 and 50 000 plants ha−1 and beans at a fixed density of 50 000 plants ha−1).

RESULTS: In monoculture, maize yield per plant increased as planting density decreased from 100 000 to 50 000 plants ha−1. At a density of 50 000 maize plants ha−1, both dry weight yield per plant and shoot N concentrations of maize were greater when intercropped with 50 000 Type III (bush‐type) bean plants ha−1 than in monoculture (196.4 g plant−1 and 167.0 g plant−1; 21.6 g N kg−1 dry mass and 17.4 g N kg−1 dry mass, respectively), but intercropping Type IV (climbing) beans at this density combination had no effects on either maize plant weight or shoot N concentration. Invariably, however, the beans grown at 50 000 plants ha−1 were adversely affected by competition with maize at all densities. Weight per plant of both Type III (bush‐type) and Type IV (climbing) beans grown in competition with 50 000 maize plants ha−1 was only about half that of when grown alone. Intercropping gave increased mycorrhizal colonization of both species, especially in unfertilized plots, and gave a higher shoot N concentration in the maize. The beans had more nodules in the intercrop than in the monocrop.

CONCLUSIONS: Intercropping maize with Type III common bean at 50 000 plants of each species ha−1 increases yield per maize plant above that of monoculture maize at 50 000 plants ha−1, despite plant density being doubled. This increase is brought about by increased maize shoot N concentration. Mycorrhizal infection of both species, and bean plant nodulation, are stimulated, and N moves from the beans to the maize. Copyright © 2008 Society of Chemical Industry
Agricultural trajectories in a Mediterranean mountain region (Priorat, NE Spain) as a consequence of vineyard conversion plans
Authors: Cots‐Folch R. , Martínez‐Casasnovas J. A. , Ramos M. C.
Published: October 2008

In mountain regions of Mediterranean European countries, recent economic and technologic changes have involved the intensification of crops, based on heavy land levelling and/or terracing, and the abandonment or marginalization of traditional land use management. These trends have been reinforced by the subsidy policies of the European Union. The objectives of the present research were: (a) to contribute to the understanding of agricultural trajectories and farming systems that are entirely transforming the social and environmental characteristics of Mediterranean mountain areas, focusing on the analysis of the main agricultural trajectories in a sample area of this environment (the Priorat region, NE Spain) over the last 20 years (1986–2005); and (b) to analyse the farming systems that coexist in the region with regard to the landscape impacts they involve and the influence of CAP subsidies in each one. A methodological approach based on the combination of multivariate statistical techniques was used to obtain a better knowledge of the heterogeneity of farming systems on a local scale. The results show that, although most farms cultivate a mosaic of traditional crops and have small mechanized areas, a minority group follows a high intensification and specialization strategy based on new mechanized‐terraced vineyards. This group only comprises 12 per cent of the farmers in the region, but owns 61 per cent of the new vineyard plantations and 42 per cent of the total agricultural land, receiving most of the subsidies from the EU vineyard conversion and restructuring policy (68 per cent of total Common Agricultural Policy (CAP) subsidies assigned to the region). Copyright © 2008 John Wiley & Sons, Ltd.
Threshold wind velocity as an index of soil susceptibility to wind erosion under variable climatic conditions
Authors: de Oro Laura A. , Buschiazzo Daniel E.
Published: October 2008

Wind erosion starts when the threshold wind velocity (µt) is exceeded. We evaluated the sensitivity of µt to determine the wind erosion susceptibility of soils under variable climatic conditions. Three years field data were used to calculate µt by means of the equation µt = ū ‐ σ Φ−1 (γ), where ū is the mean wind speed (m s−1), σ the ū standard deviation (m s−1), γ the saltation activity and Φ the standard normal distribution function of γ. Saltation activity was measured with a piezoelectric sensor (Sensit). Results showed that ū of the whole studied period (3·41 m s−1) was lower than µt (7·53 m s−1), therefore, wind erosion was produced mainly by wind gusts. The µt values ordered in the sequence: Winter (6·10 m s−1) < Spring (8·22 m s−1) = Summer (8·28 m s−1) < Autumn (26·48 m s−1). Higher µt values were related to higher air humidity and lower wind speeds and temperatures. The µt values did not agree with the erosion amounts of each season, which ordered as follows: Summer (12·88 t ha−1) > Spring (3·11 t ha−1) = Winter (0·17 t ha−1) = Autumn (no erosion). Low µt and erosion amounts of Winter were produced by a scarce number of gusts during eroding storms. We concluded that µt is useful as an index of soil susceptibility to wind erosion of different climatic periods. The use of a unique µt value in wind erosion prediction models can lead to erroneous wind erosion calculations. Copyright © 2008 John Wiley & Sons, Ltd.
Arbuscular mycorrhizal fungi in degraded typical steppe of inner Mongolia
Authors: Tian H. , Gai J. P. , Zhang J. L. , Christie P. , Li X. L.
Published: October 2008

Arbuscular mycorrhizal (AM) fungi may have some potential use in the restoration of degraded grassland through beneficial effects on plant growth and soil quality. A field investigation was conducted in three grassland sites of typical steppe in Inner Mongolia. The three plant communities, one of which was undegraded, one moderately degraded and the third severely degraded, were studied by collecting soil samples and samples of four plant species that occurred in all three sites. The percentage of root length colonized by AM fungi was estimated and the species composition and diversity of AM fungus spores recovered from the soil were determined using spore morphological characteristics. Although differences between the sites may have been due partly to other factors, it is likely that the degree of degradation was an important factor. No decline was found in the AM colonization of the roots of the indicator plant species in the moderately or severely degraded plant communities, and two plant species showed higher colonization status in the two degraded areas. Glomus geosporum and Scutellospora calospora were the dominant AM fungi in the undegraded steppe, while G. geosporum and Glomus aggregatum dominated the two degraded sites which also had low spore densities, species richness and diversity indices. However, different AM species showed different distributions among the three plant communities and the results indicate that both biotic and abiotic factors were important in determining the AMF communities, with biotic factors possibly the more important. Copyright © 2008 John Wiley & Sons, Ltd.
Chitosan Molecules Deposited from Supercritical Carbon Dioxide on a Substrate: Visualization and Conformational Analysis
Authors: Gallyamov Marat O. , Chaschin Ivan S. , Gamzazade Arif I. , Khokhlov Alexei R.
Published: October 2008

We deposited single individual macromolecules of chitosan directly from their solutions in supercritical carbon dioxide onto a substrate surface and applied SFM method to analyze the macromolecular conformation. By means of image processing of many different SFM‐contours of the visualized individual macromolecules, we determined the scaling exponent ν, which describes the correlation between mean square end‐to‐end distances and contour lengths of the adsorbed macromolecules. It was revealed, that the macromolecules, deposited from scCO2 and visualized by SFM, tended to adopt rather extended conformation. The scaling exponent ν was found to be in range of 0.78–0.8, which was slightly above the 3/4 value, corresponding to 2D self‐avoiding walk statistics. Good adhesion of chitosan coatings directly deposited from scCO2 is expected.

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Mitochondria‐targeted disruptors and inhibitors of cytochrome c/cardiolipin peroxidase complexes: A new strategy in anti‐apoptotic drug discovery
Authors: Kagan Valerian E. , Bayir Ayse , Bayir Hulya , Stoyanovsky Detcho , Borisenko Grigory G. , Tyurina Yulia Y. , Wipf Peter , Atkinson Jeffrey , Greenberger Joel S. , Chapkin Robert S. , Belikova Natalia A.
Published: October 2008

Thre critical role of mitochondria in programmed cell death leads to the design of mitochondriotropic agents as a strategy in regulating apoptosis. For anticancer therapy, stimulation of proapoptotic mitochondrial events in tumor cells and their suppression in surrounding normal cells represents a promising paradigm for new therapies. Different approaches targeting regulation of components of mitochondrial antioxidant system such as Mn‐SOD demonstrated significant antitumor efficiency, particularly in combination therapy. This review is focused on a newly discovered early stage of mitochondria‐dependent apoptosis – oxidative lipid signaling involving a mitochondria‐specific phospholipid cardiolipin (CL). Cytochrome c (cyt c) acts as a CL‐specific peroxidase very early in apoptosis. At this stage, the hostile events are still secluded within the mitochondria and do not reach the cytosolic targets. CL oxidation process is required for the release of pro‐apoptotic factors into the cytosol. Manipulation of cyt c interactions with CL, inhibition of peroxidase activity, and prevention of CL peroxidation are prime targets for the discovery of anti‐apoptotic drugs acting before the “point‐of‐no‐return” in the fulfillment of the cell death program. Therefore, mitochondria‐targeted disruptors and inhibitors of cyt c/CL peroxidase complexes and suppression of CL peroxidation represent new strategies in anti‐apoptotic drug discovery.
Absorption, metabolism and excretion of Choladi green tea flavan‐3‐ols by humans
Authors: Stalmach Angélique , Troufflard Stéphanie , Serafini Mauro , Crozier Alan
Published: October 2008

Ten healthy human subjects consumed 500 mL of Choladi green tea, containing 648 μmol of flavan‐3‐ols after which plasma and urine were collected over a 24 h period and analysed by HPLC‐MS. Plasma contained a total of ten metabolites, in the form of O‐methylated, sulphated and glucuronide conjugates of (epi)catechin and (epi)gallocatechin, with 29–126 nM peak plasma concentrations (Cmax) occurring 1.6–2.3 h after ingestion, indicative of absorption in the small intestine. Plasma also contained unmetabolised (–)‐epigallocatechin‐3‐gallate and (–)‐epicatechin‐3‐gallate with respective Cmax values of 55 and 25 nM. Urine excreted 0–24 h after consumption of green tea contained 15 metabolites of (epi)catechin and (epi)gallocatechin, but (–)‐epigallocatechin‐3‐gallate and (–)‐epicatechin‐3‐gallate were not detected. Overall flavan‐3‐ol metabolite excretion was equivalent to 8.1% of intake, however, urinary (epi)gallocatechin metabolites corresponded to 11.4% of (epi)gallocatechin ingestion while (epi)catechin metabolites were detected in amounts equivalent to 28.5% of (epi)catechin intake. These findings imply that (epi)catechins are highly bioavailable, being absorbed and excreted to a much greater extent than most other flavonoids. It is also evident that flavan‐3‐ol metabolites are rapidly turned over in the circulatory system and as a consequence Cmax values are not an accurate quantitative indicator of the extent to which absorption occurs.
Performance of some metaheuristic algorithms for localization in wireless sensor networks
Authors: Gopakumar Aloor , Jacob Lillykutty
Published: October 2008

In this paper we propose two novel and computationally efficient metaheuristic algorithms based on tabu search (TS) and particle swarm optimization (PSO) principles for locating the sensor nodes in a distributed wireless sensor network (WSN) environment. The WSN localization problem is formulated as a non‐linear optimization problem with mean squared range error resulting from noisy distance measurement as the objective function. Unlike gradient descent methods, both TS and PSO methods ensure minimization of the objective function without the solution being trapped into local optima. We further implement a refinement phase with error propagation control for improvement of the results. The performance of the proposed algorithms are compared with each other and also against simulated annealing based WSN localization. The effects of range measurement error, anchor node density and uncertainty in the anchor node position on localization performance are also studied through various simulations. The simulation results establish better accuracy, computational efficiency and convergence characteristics for TS and PSO methods. Further, the efficacy of the proposed methods is verified with data collected from an experimental sensor network reported in the literature. Copyright © 2008 John Wiley & Sons, Ltd.
A modified reliable distance algorithm for octree‐encoded objects
Authors: Dyllong Eva , Grimm Cornelius
Published: October 2008

Among other approaches, such as implicit surfaces, constructive solid geometry and boundary representations, octrees provide a powerful technique for the geometric modeling of rigid objects. A multibody system can be modeled with a composition of octrees for efficient collision detection or collision prevention applications. In this paper, we provide an algorithm for a reliable distance calculation of octree‐encoded objects. The algorithm is based on previous algorithms by Dyllong and Luther [2, 3] and has running times that are considerably shorter in different case scenarios. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Direct and inverse modeling for stochastic passive microbead rheology
Authors: Hohenegger Christel , Forest M. Gregory
Published: October 2008

The need in biology to understand the rheological properties of cells, tissues, membranes, and biological liquids, has led to new techniques in microrheology, where passive bead tracking is the fundamental probe of viscoelastic properties. We present stochastic methods for direct and inverse characterization based on noisy time series associated with either one or multiple beads, focusing on the distinctions in bead statistics due to bead‐bead hydrodynamic interactions versus the ratio of bead separation distance and bead radii. Our modeling combines the seminal works of Mason & Weitz for single bead statistics and of Crocker‐Levine‐Lubensky for 2‐bead statistics, together with the recent methods of the authors on direct and inverse simulation tools for generalized Langevin equations. The aim is to develop statistically accurate and fast direct simulation tools for bead‐bead fluctuations, and then inversion methods derived from maximum likelihood methods and the Kalman filter. The application is to support experiments by R. Superfine and D. Hill and for characterization and simulations of transport mechanisms in lung airway surface liquids within the Virtual Lung Project at UNC Chapel Hill. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computing the characteristic values of partial retarded functional differential equations
Authors: Breda Dimitri , Maset Stefano , Vermiglio Rossana
Published: October 2008

The stability of an equilibrium point of a dynamical system is determined by the position in the complex plane of the so‐called characteristic values of the linearization around the equilibrium. This work presents an approach for the computation of characteristic values of partial differential equations of evolution involving time delay, based on a coupled pseudospectral‐spectral method. Convergence of computed values is of infinite order with respect to the pseudospectral discretization and of finite order with respect to the spectral one. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal reclamation of polluted rivers
Authors: Alvarez‐Vázquez L.J. , Martínez A. , Vázquez‐Méndez M.E. , Vilar M.
Published: October 2008

This work uses mathematical modelling and numerical optimization to obtain the optimal purification of a polluted section of a river, by finding the minimum quantity of water to be injected into the river in order to purify it up to a fixed level. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Parameter identification for a two‐scale model of reactive transport in porous media – some first steps
Authors: Meier Sebastian , Böhm Michael
Published: October 2008

We formulate a mathematical setting for recovering microscopic parameters from macroscopic measurements by means of a two‐scale model. The model describes reaction and diffusion of a chemical substance in two phases of a porous medium. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Assimilation of remote sensed data for river hydraulic simulations
Authors: Monnier Jérôme , Honnorat Marc , Lai Xijun , Dimet Francois‐Xavier Le
Published: October 2008

We present variational data assimilation methods applied to river hydraulics, especially when flooding. We consider two kinds of configurations. First, if observations are lagrangian trajectories (either extracted from videos or GPS drifting buoys); second, if observations include one satellite image of flood plain. Numerical results (with synthetic or real data) are presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental validation of a viscoelastic material model for numerical simulation of the extrusion process of rubber blends
Authors: Müllner Herbert W. , Wieczorek André , Petracek Pia I. , Eberhardsteiner Josef
Published: October 2008

The goal of this contribution is the validation of a viscoelastic material model, which allows consideration of the interaction of the typical swelling behavior of viscoelastic fluids and the shear rate dependent viscosity of industrial used rubber blends in the context of an extrusion process. With this knowledge more realistic numerical simulations of the die swell phenomenon and its influence on the resulting profile geometry are possible. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A parallel eigenvalue problem solver for computational nanoelectronics
Authors: Naumov Maxim , Sameh Ahmed
Published: October 2008

A new parallel eigenvalue solver for finding the interior eigenvalues of a standard Hermitian eigenvalue problem arising in atomistic simulations in nanoelectronics is presented. It is based on the Tracemin algorithm which finds the p smallest eigenpairs of a generalized Hermitian eigenvalue problem. The original problem is modified using spectrum folding or a quadratic mapping so that the interior eigenvalues are mapped onto the smallest or the largest, respectively. In the latter case the solution of systems in every iteration of Tracemin is avoided and Chebyshev polynomials are used to speedup convergence. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Criterium for the gradient catastrophe for the non‐isentropic gas dynamics equations in the one dimensional case
Authors: Rozanova Olga
Published: October 2008

A method to describe the motion of non‐isentropic polytropic gas by means of integral functionals is proposed. They are as a matter of fact the integrals of the solution components over a material volume. Included among the functionals are the kinetic and potential energies, impulse, momentum of mass, and a number of specific integrals. These integral functionals are functions of time and satisfy to a system of ODE, which is closed provided we consider a linear velocity field. In 1D case the system can be reduced to a certain nonlinear second order ODE for the first derivative in space of velocity. The problem about the data yielding the gradient catastrophe (the unboundedness of the solution gradients) can be reduced to the problem of blow‐up of the solutions to the latter equation. This problem can be completely solved, so, the criterium of the gradient catastrophe can be obtained. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stabilizing the Burnett fluid dynamics equations
Authors: Söderholm Lars H.
Published: October 2008

Combining multple time expansion and Hilbert expansion, the wellknown difficulties of the Hilbert expansion are overcome. Here it is shown also that the resulting equations to second order in the Knudsen number can be summed and a set of equations are obtained which does not suffer from the Bobylev instability (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A semi‐smooth Newton method for an inverse problem in option pricing
Authors: Düring Bertram
Published: October 2008

We present an optimal control approach using a Lagrangian framework to identify local volatility functions from given option prices. We employ a globalized sequential quadratic programming (SQP) algorithm and implement a line search strategy. The linear‐quadratic optimal control problems in each iteration are solved by a primal‐dual active set strategy which leads to a semi‐smooth Newton method. We present first‐ and second‐order analysis as well as numerical results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Active control of combustion instability using fuel flow modulation
Authors: Guyot Daniel , Bothien Mirko R. , Moeck Jonas P. , Paschereit C. O.
Published: October 2008

Phase‐shift control was applied to an atmospheric premix combustor test rig equipped with a swirl‐stabilized burner by modulating the pilot fuel flow. The employed closed loop control circuit incorporated condenser microphones recording the pressure oscillations inside the combustion chamber and valves controlling the fuel mass flow. The microphone signals were processed and command signals were sent to the valves. The rms of the pressure oscillations was reduced by up to 12 dB, the peak amplitude by up to 20 dB. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the bottom undulation on surface waves in thin film flow
Authors: Heining Christian , Wierschem Andreas , Aksel Nuri
Published: October 2008

We study gravity‐driven viscous thin films flowing down an undulated plane. Applying the integral boundary‐layer method we derive a set of two coupled PDEs for the film thickness and the flow rate. The steady state solution shows linear and nonlinear resonance. Based on this analytical solution we carry out a stability analysis with respect to surface waves and study wave generation and annihilation for time dependent flow. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Linearized description of the flow of a vapor with condensation and evaporation through a micro‐porous membrane
Authors: Loimer Thomas
Published: October 2008

It is shown that a fluid which flows through a micro‐porous membrane and which is in a state of saturated vapor upstream of the porous membrane condenses fully or partially and re‐evaporates further downstream. Several types of flow can occur. Either liquid, a two‐phase mixture or vapor flow through a part or all of the membrane. The dimensionless groups characterizing the flow process are given and a flow map is drawn to show the conditions under which the different types of flow occur. For a specific case, the mass flux is calculated according to the description presented here and a comparison is made with experimental data and with an isothermal description of the flow. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)