bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Design and Synthesis of Dansyl‐Containing Cyclic Pseudopeptides
Authors: Angelici Gaetano , Tresanchez Carrera Roger , Luppi Gianlugi , Tomasini Claudia 
Published: June 2008

AbstractSix cyclic pseudopeptides with the general formula cyclo‐(L‐AA‐D‐Oxd)n [where AA is an α‐amino acid, D‐Oxd is trans‐(4R,5S)‐4‐carboxy‐5‐methyloxazolidin‐2‐one and n = 3, 4] have been designed and efficiently synthesized in the liquid phase in good overall yields. The crucial step is the macrocyclization, which always occurs in satisfactory yields regardless of the cycle dimension and the nature of various functional groups in the side‐chain. Moreover, a dansyl (dansyl = 5‐dimethylamino‐1‐naphthylsulfonyl) unit was introduced into the side‐chain with the aim of preparing a labelled cyclopeptide that can be easily located in a biological environment. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Photoinduced Electron Transfer in Branched Bis(ferrocenylacetylene)‐C60Systems: Influence of the Nature of Conjugation
Authors: Pérez Laura , Shafiqul Islam D.‐M. , Araki Yasuyuki , de la Cruz Pilar , Cardinali François , Ito Osamu , Langa Fernando 
Published: June 2008

AbstractFour new branched 3,4‐ and 3,5‐bis(ferrocenylacetylene)phenyl‐C60molcules, in which the bis‐ferrocene donor moieties and C60acceptor moiety are covalently linked with phenylacetylene linkage through pyrrolidino and pyrazolino rings on the C60moiety, as abbreviated to be (Fc)2≡Ph‐NMPC60(o‐ andm‐) and (Fc)2≡Ph‐PzC60(o‐ andm‐), respectively, have been prepared in multistep procedures using microwave irradiation, as source of energy. The HOMO–LUMO gaps smaller than 1.25 eV were experimentally determined by cyclic voltammetry (CV) and Osteryoung square‐wave voltammetry (OSWV) for (Fc)2≡Ph‐PzC60and (Fc)2≡Ph‐NMPC60. In both polar and non‐polar solvents, a photoinduced charge‐separation (CS) process efficiently takes place in (Fc)2≡Ph‐NMPC60and (Fc)2≡Ph‐PzC60from the singlet excited state of C60(1C60*), as confirmed by picosecond‐time‐resolved emission spectroscopy. The CS states were confirmed by nanosecond‐transient absorption spectroscopy. The lifetimes of the CS states were evaluated to be ca. 10 ns, which are shorter than those of the similar dyads with phenylenevinylene linkage, suggesting higher electron‐hole conductivity through the phenylacetylene linkage.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The Effect of Lewis Acids on the Stereochemistry in the Ugi Three‐Component Reaction with D‐lyxo‐Pyrroline
Authors: Bonger Kimberly M. , Wennekes Tom , Filippov Dmitri V. , Lodder Gerrit , van der Marel Gijsbert A. , Overkleeft Herman S. 
Published: June 2008

AbstractA library of polyhydroxylated pyrrolidines was obtained by performing a tandem Staudinger/aza‐Wittig/Ugi three‐component reaction on a L‐ribose‐derived 4‐azido aldehyde. In this paper we describe the effect of Lewis acids on the diastereoselectivity of the final Ugi three‐component reaction step that the intermediate (D‐lyxo‐pyrroline) cyclic imine undergoes. When the Ugi reaction was performed in methanol almost exclusively pyrrolidines with a 2,3‐cis relationship were formed. However, a significant amount of 2,3‐trans product was formed upon addition of Lewis acids to the Ugi reaction mixture. The scope of this effect is explored by evaluating a diverse set of Lewis acids in combination with variation of other reaction parameters and the carboxylic acid/isocyanide component. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Uncertainty assessment of a soil quality index using geostatistics
Authors: Castrignanò A. , Buondonno A. , Odierna P. , Fiorentino C. , Coppola E. 
Published: June 2008

AbstractThe soil quality in the Asa–Picentino–Tusciano rivers basin (Campania region, southern Italy) was assessed through a novel synthetic, highly informative numerical index. The study area is characterized by a wide spatial heterogeneity. A combined approach, based on geostatistics linked with GIS techniques, was applied to estimate the spatial index and also provide an assessment of estimation uncertainty. The geostatistics‐based approach, described in this work, might be advantageously used to direct sampling and/or delineate fertility capability zones in decision making and land use planning. Copyright © 2008 John Wiley & Sons, Ltd.
Detailed characterization of a homozygously deleted region corresponding to a candidate tumor suppressor locus at 21q11‐21 in human lung cancer
Authors: Yamada Hideki , Yanagisawa Kiyoshi , Tokumaru Shogo , Taguchi Ayumu , Nimura Yuji , Osada Hirotaka , Nagino Masato , Takahashi Takashi 
Published: June 2008

AbstractThe frequent presence of loss of heterozygosity (LOH) at 21q21 in lung cancer suggests the existence of putative tumor suppressor genes in this genomic region. Furthermore, the identification of a homozygous deletion in this region has lent further support for its potential involvement in pathogenesis. In the present study, extensive screening of a large panel of lung cancer cell lines resulted in the identification of a homozygous deletion at 21q21.1 in the large cell lung carcinoma cell line Calu‐6. Subsequent detailed characterization allowed us to narrow down the extent of the shortest region of overlap of homozygous deletions at 21q21.1 to 3.4 Mbp. Together with existing information showing a relationship with the shortest region of overlap and LOH in lung cancer, the overlapping 1.8‐Mbp region was suggested to be a prime candidate for a genomic region that may harbor putative tumor suppressor genes. We found frequent downregulation of two coding genes, SAMSN1 and USP25, as well as of three miRNA genes, miR‐99a, let‐7c, and miR‐125b‐2, which reside in the commonly deleted region in human lung cancer. In addition, initial attempts were made to investigate their potential alterations and functional involvements in the development of lung cancer. © 2008 Wiley‐Liss, Inc.
An approach to catchment‐scale groundwater nitrate risk assessment from diffuse agricultural sources: a case study in the Upper Bann, Northern Ireland
Authors: Wang J. L. , Yang Y. S. 
Published: June 2008

AbstractDRASTIC has drawbacks in groundwater risk assessment that are important in guiding activities to prevention agricultural diffuse groundwater pollution. This paper presents an improved and GIS‐based D‐DRASTIC approach for groundwater nitrate risk assessment from diffuse agricultural sources based on DRASTIC. D‐DRASTIC considers the risk concept, nitrate loading, pollutant transport with runoff, depth to water, net recharge, aquifer media, soil media, topography, impact of the vadose zone media, and the hydraulic conductivity of the aquifer. D‐DRASTIC was developed within an ArcGIS environment and applied to the Upper Bann Catchment, Northern Ireland as a case study. D‐DRASTIC shows that ‘very high’ and ‘high’ zones of groundwater nitrate risk occupy 5% and 11% of the case study area, respectively. When considering groundwater pollution sources and pathways, the results using D‐DRASTIC are helpful in guiding the activities of groundwater pollution prevention at the catchment scale in the context of better implementation of the EU Water Framework Directive. Copyright © 2008 John Wiley & Sons, Ltd.
Estimating parameters of groundwater recharge model in frequency domain: Karst springs Jadro and Žrnovnica
Authors: Jukić Damir , Denić‐Jukić Vesna 
Published: June 2008

AbstractThe spectral method is based on the assumption of exponential forms of autocorrelation functions of the input and output time series. The results of practical applications of the spectral method on several karst springs in Croatia show that this assumption cannot always be reliably applied to the time series of rainfall and spring discharge, especially if short time periods are analysed. For this reason, the method is modified. The scale factor between the transfer function of total rainfall and the transfer function of groundwater recharge is considered as an additional model parameter which is determined in the optimization procedure. In addition to the theoretical background, this paper also presents the results of application of the modified spectral method on the springs Jadro and Žrnovnica located in the Dinaric karst area in Croatia. The parameters of groundwater recharge model are determined separately for both the springs and the obtained values are discussed and compared with the results of previous investigations. The values of the scale factors determined in the optimization procedure are compared to the values calculated using the theoretical equation. The comparison shows that the theoretical equation underestimates the optimal values of the scale factor. The underestimations are especially evident for periods of one year. Finally, the characteristics of rainfall–runoff relations of two springs are compared using the identified transfer functions and the results of simulations of the periodogram of observed discharge by the parametric periodogram. Copyright © 2008 John Wiley & Sons, Ltd.
Recent studies on surface water–groundwater relationships at hydro‐projects in India using environmental isotopes
Authors: Kumar U. Saravana , Sharma Suman , Navada S.V. 
Published: June 2008

AbstractEnvironmental isotopes (2H or D, 18O, 3H), along with geology, hydrochemistry and in situ physicochemical parameters (EC, T, DO, pH) were employed to study surface water (reservoir, lake)–groundwater (spring) relationships at (1) Nagewadi, a minor irrigation project in the State of Maharashtra, Western India; (2) Kanhirapuzha reservoir in the State of Kerala, Southern India and (3) Ghatghar Pumped Storage Hydroelectric Project in the State of Maharashtra, Western India for the purpose of understanding the seepage/leakage and its associated problems. The studies concluded that the springs found downstream of the Nagewadi project originate from the reservoir and not from the abutments or shallow aquifers. The Kanhirapuzha reservoir receives a substantial base‐flow component compared to riverine inputs. The reason for the water‐logging problem at a nearby downstream village during the non‐summer periods is due to the change in the upstream groundwater flow direction under reservoir filling conditions and is not due to reservoir leakage. Most of the springs in the approach tunnel to the underground power house of the Ghatghar Project originate from the lower reservoir and not from the upper reservoir or the overburden rock matrix. The above case studies illustrate the diversity of environmental isotope applications in surface water (reservoir, lake)–groundwater (spring) relationships related to sustainability of hydro‐projects. Copyright © 2008 John Wiley & Sons, Ltd.
A comparison of three methods for determining vineyard evapotranspiration in the arid desert regions of northwest China
Authors: Li Sien , Kang Shaozhong , Zhang Lu , Li Fusheng , Zhu Zhilin , Zhang Baozhong 
Published: June 2008

AbstractAccurate measurement and estimation of crop evapotranspiration (ET) plays an important role in understanding field soil water cycle and managing water‐saving irrigation in the arid regions. This study compares three methods for estimating ET: field Water Balance (WB), Eddy Covariance (EC) and Bowen Ratio‐Energy Balance (BREB). The experiment was conducted in a vineyard in the arid desert regions of northwest China. Results indicate that the three methods provided similar estimate of total ET. Compared to total ET measured by WB (ETWB) during the whole growing stage, total ET estimated by EC (ETEC) was 1·57% lower, and total ET estimated by BREB (ETBREB) was 5·19% higher. Variations of ETEC and ETBREB are similar at hourly or daily timescale, but the values are slightly different. At sunrise or sunset, ETBREB increases or decreases more rapidly than ETEC. The difference between ETBREB and ETEC is linearly related to the residual of the energy balance for EC and the two methods yielded close estimates when the residual was small. This study showed that the three methods provided accurate estimates of ET at daily and seasonal timescales and the methods can be used to estimate ET from vineyards in arid environments. Copyright © 2008 John Wiley & Sons, Ltd.
Spatial variation of isotope composition in precipitation in a tropical environment: a case study from the Deduru Oya river basin, Sri Lanka
Authors: Jayasena H.A.H. , Chandrajith Rohana , Dissanayake C.B. 
Published: June 2008

AbstractThe stable isotope composition (18O and 2H) in the tropical precipitation collected from 18 locations throughout the Deduru Oya river basin in Sri Lanka, has been studied during August and September 2001, in order to characterize the isotopic composition of precipitation in the dry and intermediate climatic zones of Sri Lanka. The isotope compositions are described with respect to the distance from the coast and the altitude. The analyses show that δ18O vary from − 5·11 to 1·39‰ and δD vary from − 35·71 to 12·55‰. The d‐excess values range from − 0·65 to 13·17 with an average value of ∼7. Regression for the δ18O − δD is y = 6·8x + 4·9 (R2 = 0·9) which is compatible with the precipitation in other tropical regions. The lower slope in the regression line and the lower d‐excess value indicate high temperature events which were possibly aided by concentration through successive evaporation within the atmosphere. The spatial variation of isotope composition indicates two different cloud contributions for the rain events, of which one may be linked to the Indian Ocean contribution and the other to the high altitude condensation. Copyright © 2008 John Wiley & Sons, Ltd.
Fast segmentation algorithms for long hydrometeorological time series
Authors: Aksoy Hafzullah , Gedikli Abdullah , Unal N. Erdem , Kehagias Athanasios 
Published: June 2008

AbstractA time series with natural or artificially created inhomogeneities can be segmented into parts with different statistical characteristics. In this study, three algorithms are presented for time series segmentation; the first is based on dynamic programming and the second and the third—the latter being an improved version of the former—are based on the branch‐and‐bound approach. The algorithms divide the time series into segments using the first order statistical moment (average). Tested on real world time series of several hundred or even over a thousand terms the algorithms perform segmentation satisfactorily and fast. Copyright © 2008 John Wiley & Sons, Ltd.
Effect of seeding technique and scaffold material on bone formation in tissue‐engineered constructs
Authors: Schliephake H. , Zghoul N. , Jäger V. , van Griensven M. , Zeichen J. , Gelinsky M. , Wülfing T. 
Published: June 2008

AbstractThe aim of the present study was to test the hypothesis that both scaffold material and the type of cell culturing contribute to the results of in vivo osteogenesis in tissue‐engineered constructs in an interactive manner. CaCO3 scaffolds and mineralized collagen scaffolds were seeded with human trabecular bone cells at a density of 5 × 106 cells/cm3 and were left to attach under standard conditions for 24 h. Subsequently, they were submitted to static and dynamic culturing for 14 days (groups III and IV, respectively). Dynamic culturing was carried out in a continuous flow perfusion bioreactor. Empty scaffolds and scaffolds that were seeded with cells and kept under standard conditions for 24 h served as controls (groups I and II, respectively). Five scaffolds of each biomaterial and from each group were implanted into the gluteal muscles of rnu rats for 6 weeks. Osteogenesis was assessed quantitatively by histomorphometry and expression of osteocalcin (OC) and vascular endothelial growth factor (VEGF) was determined by immunohistochemistry. CaCO3 scaffolds exhibited 15.8% (SD 3.1) of newly formed bone after static culture and 22.4% (SD 8.2) after dynamic culture. Empty control scaffolds did not show bone formation, and scaffolds after 24 h of standard conditions produced 8.2% of newly formed bone (SD 4.0). Differences between the controls and the scaffolds cultured for 14 days were significant, but there was no significant difference between static and dynamic culturing. Mineralized collagen scaffolds did not show bone formation in any group. There was a significant difference in the expression of OC within the scaffolds submitted to static versus dynamic culturing in the CaCO3 scaffolds. VEGF expression did not show significant differences between static and dynamic culturing in the two biomaterials tested. It is concluded that within the limitations of the study the type of biomaterial had the dominant effect on in vivo bone formation in small tissue‐engineered scaffolds. The culture period additionally affected the amount of bone formed, whereas the type of culturing may have had a positive effect on the expression of osteogenic markers but not on the quantity of bone formation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Effects of physiological mechanical strains on the release of growth factors and the expression of differentiation marker genes in human osteoblasts growing on Ti‐6Al‐4V
Authors: Kokkinos Petros A. , Zarkadis Ioannis K. , Kletsas Dimitris , Deligianni Despina D. 
Published: June 2008

AbstractMechanical loading factors at the bone‐implant interface are critical for the osseointegration and clinical success of the implant. The aim of the present investigation was to study the effects of mechanical strain on the orthopedic biomaterial Ti‐6Al‐4V/osteoblast interface, using an in vitro model. Homogeneous strain was applied to human bone marrow derived osteoblasts (HBMDOs) cultured on Ti‐6Al‐4V, at physiological levels (strain magnitudes 500 microstrain (με) and 1000 με, at frequencies of load application 0.5 Hz and 1 Hz), by a mechanostimulatory system, based on the principle of four‐point bending. Semi‐quantitative reverse transcription‐polymerase chain reaction (sqRT‐PCR) was used to determine the mRNA expression of Cbfa1 and osteocalcin at different loading conditions. The release of growth factors as a response to stretch was also investigated by transferring stretch‐conditioned media to nonstretched cells and by measuring their effect on the regulation of DNA synthesis. Mechanical loading was found to contribute to the regulation of osteoblast differentiation by influencing the level of the osteoblast‐specific transcription factor Cbfa1, both at the mRNA and protein level, and also the level of osteocalcin, which is regarded as the most osteoblast‐specific gene. Both genes were differentially expressed shortly after the application of different mechanical stimuli, in terms of strain frequency, magnitude, and time interval. Media conditioned from mechanically stressed HBMDOs stimulate DNA synthesis more intensely compared to media conditioned from unstressed control cultures, indicating that mechanical strain induces the release of a mitogenic potential that regulates cell proliferation. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Histomorphometric evaluation of immediately loaded SSII implants of different surface treatments in a dog model
Authors: Jeon Woo‐Jin , Kim Su‐Gwan , Lim Sung‐Chul , Ong Joo L. , Oh Daniel Sunho 
Published: June 2008

AbstractThis study compared splint (experimental) and nonsplint (control) methods for immediately loaded implants and examined the bone–implant contact rate for smooth, oxidized, and resorbable blast medium (RBM) surfaces. The first through fourth mandibular premolars were extracted from six young adult dogs. Twelve weeks after extraction, implantation was performed at the extraction sites. The SSII OSSTEM implant had one of three surface treatments: smooth, oxidized, or RBM. Sixteen weeks after implantation, the dogs were euthanized; the hemimandibles were obtained and processed histologically to obtain nondecalcified sections. Longitudinal sections were made for each implant and analyzed using light microscopy. Independent of the splinting method, a significantly higher bone–implant contact was observed for implants with oxidized and RBM surfaces when compared with implants with smooth surfaces. Irrespective of the splinting method, immediately loaded implants with oxidized and RBM surfaces may result in higher bone–implant integration when compared with implants with smooth surfaces. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Subproteomic analysis of the mitochondrial proteins in rats 24 h after partial hepatectomy
Authors: Sun Qingju , Miao Mingyong , Jia Xuan , Guo Wei , Wang Lianghua , Yao Zhenzhen , Liu Chunli , Jiao Binghua 
Published: June 2008

AbstractA 70% partial hepatectomy (70%PHx) induces cell proliferation until the original mass of the liver is restored. Mitochondria are involved directly in the process of liver regeneration (LR); however, their role in the early phase of LR is not clear. In an attempt to identify mitochondrial proteins that are correlated with the early phase of LR, we obtained a mitochondrial fraction via Nycodenz® density gradient centrifugation and subcellular proteomic analysis was performed. The mitochondrial proteins were separated by two‐dimensional gel electrophoresis and identified by mass spectrometry. Compared to the sham‐operation control group, 3 proteins were up‐regulated and 22 proteins were down‐regulated at 24 h after 70%PHx. We identified 22 differentially expressed proteins that were associated with carbohydrate metabolism, lipid metabolism, the respiratory chain and oxidation–phosphorylation, biotransformation and other metabolic pathways. Prohibitin, a proliferation‐regulating protein that was down‐regulated at 24 h after PHx, was analyzed by applying RNAi (PHBi) with BRL‐3A. This demonstrated a decreased mitochondrial membrane potential, implying a potential role in maintaining mitochondrial integrity. These results indicated that hepatic mitochondrial adaptations to LR after 70%PHx affect various cellular metabolic pathways, which advances our knowledge of the role of mitochondria in the early phase of LR. J. Cell. Biochem. 105: 176–184, 2008. © 2008 Wiley‐Liss, Inc.
Virus infection activates thyroid stimulating hormone synthesis in intestinal epithelial cells
Authors: Varghese Shaun , Montufar‐Solis Dina , Vincent Bryce H. , Klein John R. 
Published: June 2008

AbstractThe small intestine has been shown to be an extra‐pituitary site of thyroid stimulating hormone (TSH) production, and previous in vivo studies have shown that TSH synthesis localizes within areas of enteric virus infection within the small intestine; however, the cellular source of intestinal TSH has not been adequately determined. In the present study, we have used the murine MODE‐K small intestinal epithelial cell line to demonstrate both at the transcriptional level and as a secreted hormone, as measured in a TSHβ‐specific enzyme‐linked assay, that epithelial cells in fact respond to infection with reovirus serotype 3 Dearing strain by upregulating TSH synthesis. Moreover, sequence analysis of a PCR‐amplified TSHβ product from MODE‐K cells revealed homology to mouse pituitary TSHβ. These findings have direct functional implications for understanding a TSH immune‐endocrine circuit in the small intestine. J. Cell. Biochem. 105: 271–276, 2008. © 2008 Wiley‐Liss, Inc.