bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stability, morphology and surface grain size patterns of channel bifurcation in gravel–cobble bedded anabranching rivers
Authors: Burge Leif M. 
Published: March 2006

AbstractThis study presents the first detailed field‐based analysis of the morphology of bifurcations within anabranching cobble–gravel rivers. Bifurcations divide the flow of water and sediment into downstream anabranches, thereby influencing the characteristics of the anabranches and the longevity of river islands. The history, morphology, bed grain size, and flow vectors at five bifurcations on the Renous River, New Brunswick, Canada, were studied in detail. The angles of bifurcations within five anabranching rivers in the Miramichi basin were investigated. The average bifurcation angle was 47°, within the range of values cited for braided river bifurcations. Bifurcation angle decreased when anabranches were of similar length. Shields stresses in channels upstream of bifurcations were lower than reported values for braided rivers. Stable bifurcations displayed lower Shields stresses than unstable bifurcations, contrary to experimental results from braided river bifurcations. Bifurcations in anabranching rivers are stabilized by vegetation that slows channel migration and helps to maintain a uniform upstream flow field. The morphology of stable bifurcations enhances their stability. A large bar, shaped like a shallow ramp that increases in elevation to floodplain level, forms at stable bifurcations. Floodplains at stable bifurcations accrete upstream at rates between 0·9 and 2·5 m a−1. Bars may also form within the entrance of an anabranch downstream of the bifurcation node. These bars are associated with bifurcation instability, forming after a period of stability or an avulsion. Channel abandonment occurs when a bar completely blocks the entrance to one anabranch. The stability of channels upstream of bifurcations and the location of bars at bifurcations influence bifurcation stability and the maintenance of river anabranching in the long term. Copyright © 2006 John Wiley & Sons, Ltd.
Mitochondrial DNA mutations and mitochondrial DNA depletion in breast cancer
Authors: Tseng Ling‐Ming , Yin Pen‐Hui , Chi Chin‐Wen , Hsu Chih‐Yi , Wu Chew‐Wun , Lee Liang‐Ming , Wei Yau‐Huei , Lee Hsin‐Chen 
Published: March 2006

AbstractSomatic mutations in mitochondrial DNA (mtDNA) have been demonstrated in various tumors, including breast cancer. However, it still remains unclear whether the alterations in mtDNA are related to the clinicopathological features and/or the prognosis in the breast cancer. We analyzed somatic mutations in the D‐loop region, the common 4,977‐bp deletion, and the copy number of mtDNA in breast cancer and paired nontumorous breast tissues from 60 Taiwanese patients. We found that 18 of the 60 (30%) breast cancers displayed somatic mutations in mtDNA D‐loop region. The incidence of the 4,977‐bp deletion in nontumorous breast tissues (47%) was much higher than that in breast cancers (5%). The copy number of mtDNA was significantly decreased in 38 of the 60 (63%) breast cancers as compared to their corresponding nontumorous breast tissues (P = 0.0008). The occurrence of D‐loop mutations was associated with an older onset age (≥50 years old, P = 0.042), and tumors that lacked expressions of estrogen receptor and progesterone receptor (P = 0.024). Patients with mtDNA D‐loop mutation and breast cancer had significantly poorer disease‐free survival than those without mutation, when assessed by Kaplan–Meier curves and log‐rank test (P = 0.005). Multivariate Cox regression analysis indicated that a D‐loop mutation is a significant marker that is independent of other clinical variables and that it can be used to assess the prognosis of patients. Our findings suggest that somatic mutations in mtDNA D‐loop can be used as a new molecular prognostic indicator in breast cancer. © 2006 Wiley‐Liss, Inc.
Functional imaging analysis contest (FIAC) analysis according to AFNI and SUMA
Authors: Saad Ziad S. , Chen Gang , Reynolds Richard C. , Christidis Patricia P. , Hammett Kenneth R. , Bellgowan Patrick S.F. , Cox Robert W. 
Published: March 2006

AbstractThe Functional Imaging Analysis Contest (FIAC) datasets were analyzed with the AFNI software package. Two types of linear regression analyses were carried out: “fixed shape” hemodynamic response, where a preselected incomplete gamma function is used to model each brief activation episode, and “variable shape” analysis, where the temporal shape of the response model in each stimulus block class is allowed to vary separately in each voxel. These time series regressions were carried out both in the volume and on the original data projected to individual standardized cortical surface models. Intersubject analyses were carried out voxel‐wise on the regression amplitudes obtained from these time series results, using a multi‐way within‐subject analysis of variance (ANOVA). Group analysis of the block design demonstrated a significant repetition suppression of the BOLD signal within blocks in the superior and middle temporal gyrus. This effect may represent differences in the response to the first stimulus following a period of silence compared to the remaining sentences in the block. Analyzing the event‐related data, Brodmann area 31 showed significant sentence effect and consecutive‐sentence repetition effect. However, no significant speaker effect was found; these results may be consistent with the instructions to the subjects that they would be tested on the sentence content. Sentence by speaker interaction effects were found in bilateral middle temporal gyrus, left inferior frontal, and left inferior temporal gyrus. Hum Brain Mapp, 2006. © 2006 Wiley‐Liss, Inc.
Modelling the effects of saline water use in agriculture
Authors: Kaledhonkar M. J. , Keshari Ashok K. 
Published: March 2006

AbstractUse of saline groundwaters is inevitable in rice–wheat, cotton–wheat, and millet–wheat crop rotations in the northern region of India due to limited canal water supplies. The UNSATCHEM model is calibrated and validated with field data on saline water use for the wheat and cotton crop. The calibrated and validated model has been employed to study different aspects of the salinisation process. The effect of irrigation water quality on the salinisation process is understood with the help of simulations in which irrigation waters of different SAR, SO and Cl− concentrations are used. A linear relation is observed between the weighted average of irrigation water salinity and the root zone. The salinisation process under different conjunctive use practices is understood through simulations. The practices are compared on the basis of temporal changes in root zone salinity with reference to the sensitivity of the wheat crop to salinity for deciding the preference of one conjunctive use practice over another. The preference order, thus prepared, is verified with the published yield data of wheat from conjunctive use field studies. The effect of soil texture on salinisation is studied through simulations. The saturated water content influences the salinisation process more than the hydraulic conductivity. The long‐term simulations as per water quality guidelines for a six‐year period under wheat–cotton rotation are carried out to assess the sustainability of saline water use for crop production. Copyright © 2006 John Wiley & Sons, Ltd.
Validation of the FAO methodology for computing ETo with limited data. Application to south Bulgaria
Authors: Popova Zornitsa , Kercheva Milena , Pereira Luis S. 
Published: March 2006

AbstractThe calculation of reference evapotranspiration ETo with the FAO Penman‐Monteith method (FAO‐PM) requires maximum and minimum air temperature (Tmax and Tmin), actual vapour pressure (ea), net radiation (Rn), namely computed from sunshine duration or short wave solar radiation (Rs), and wind speed at 2 m (u2). However, some of these weather variables, especially solar radiation, are often missing in irrigation practice. To overcome these problems, procedures to estimate ETo with missing climate data are proposed as part of the FAO‐PM methodology and it is important to assess the accuracy of these procedures for different climate conditions. This is the objective of this study relative to the Trace plain, south Bulgaria, where data relative to five meteorological stations in the Trace plain are analysed. All stations are located within a homogeneous physiographic region where the air masses governing the weather are the same. The procedures to estimate the missing radiation data refer to the use of the maximum and the minimum daily temperature differences and data from a neighbouring station. Procedures to estimate missing humidity data relate to the use of minimum temperature data and those for the wind speed data refer to regional average data. The accuracy of all different procedures analysed was assessed by regressing ETo values calculated with the FAO‐PM equation computed with limited data versus ETo values computed with complete data sets. Statistical parameters of the regression through the origin and the computed standard errors of estimates (SEE) were used. It could be concluded that the procedures proposed by FAO are accurate providing small SEE, including when only maximum and minimum temperature data are used, which yields lower SEE than when using the Hargreaves equation, which tends to overestimate ETo for the observed conditions. Copyright © 2006 John Wiley & Sons, Ltd.
Water management tasks in the summer polders of the Nemunas lowland
Authors: Lukianas Antanas , Vaikasas Saulius , Malisauskas Arvydas Povilas 
Published: March 2006

AbstractSurplus water during floods as well as the low level of the soil surface determine the complicated ecological, economic and demographic conditions in the Nemunas delta. Subsequently, it leads to different types and intensity of use of farmland as well as different methods of water regime regulation: summer or winter type polders. The building of 17 summer polders in the 32 500 ha floodplain area was a compromise, seeking to improve farming conditions and maintain the stability of the flood regime and ecology in the delta. Field measurements and mathematical modelling were carried out. As study results have shown, grass yield losses due to flooding depend on the distribution of water levels and flood duration in the summer polders. Relative damage to agriculture is insignificant and makes up only 10–15% of the total amount of flood damage in the Nemunas lowland.The field measurements and hydraulic and mathematical modelling of flow and sediment regime as well as study of flooding and changed farming conditions also show that it is possible to reduce the height of floods and economic and ecological damage. Rearrangement of the system of protective dikes, regulation of the main river canal and water/sedimentation regime with the help of pumping stations, decrease of pollutant migration into the Curonian Lagoon and Baltic Sea, and recreation of natural meadows are important in that case. Copyright © 2006 John Wiley & Sons, Ltd.
Photopolymerization of biomaterials: issues and potentialities in drug delivery, tissue engineering, and cell encapsulation applications
Authors: Baroli Biancamaria 
Published: March 2006

AbstractPhotopolymerization is a widely explored technology that has recently been recognized to have also great potentialities in the biomedical field. This paper aims to provide a general overview of this technology by briefly describing materials and methods used to produce linear or crosslinked polymer networks for drug delivery, tissue engineering and cell encapsulation. In addition, potentialities and areas of investigation that are not fully explored but that could provide solutions for better control over the technology when applied to the biomedical field will be indicated as well. Copyright © 2006 Society of Chemical Industry
The effect of selected parameters of formation on properties of alginate/Ca2+/oligochitosan capsules
Authors: Bartkowiak Artur , Lisiecki Sławomir , Orive Gorka , Pedraz Jose Luis 
Published: March 2006

AbstractOptimization of the technological parameters affecting the mechanical properties and permeability of capsules is essential to produce capsules with improved properties for cell immobilization. In the present paper, the effect of different parameters on the technological properties of alginate/Ca2+/oligochitosan capsules has been investigated. The correct adjustment of the alginate concentration in the polymer matrix and the oligochitosan molar mass, concentration and coating time, have been found to be key parameters in obtaining porous and mechanically stable alginate/Ca2+/oligochitosan capsules. Results showed that an increase in the coating time and concentration of the alginate generated more stable capsules with a reduced membrane cut‐off. Furthermore, we have established some correlations between capsule properties and the effectiveness of chitosan binding within the capsule's membrane. Data addressed herein could be a valid tool to fabricate optimized alginate/Ca2+/oligochitosan capsules with a potential for use in cell immobilization technology. Copyright © 2006 Society of Chemical Industry
Thermodynamics of the encapsulation by cyclodextrins
Authors: Charumanee Suporn , Titwan Aurawan , Sirithunyalug Jakkapan , Weiss‐Greiler Petra , Wolschann Peter , Viernstein Helmut , Okonogi Siriporn 
Published: March 2006

AbstractMolecular encapsulation on a molecular basis can be performed by cyclodextrins. The inclusion of organic molecules into the interior changes the properties of these molecules, which may be used for a broad variety of applications. The affinity of guest molecules for the cavities of various cyclodextrins depends on the stereochemistry and on the interaction forces of the molecules involved. Calculations of the thermodynamic parameters show that the reaction entropy is highly important for the inclusion reaction. Completely different reaction mechanisms are observed for various types of cyclodextrins as some of these reactions show enthalpy–entropy compensation. Others are supported by the reaction entropy or are even entropically controlled. Protonation and deprotonation reactions contribute significantly to the inclusion reaction, as first of all the solubility of the compounds in water is strongly influenced by the acidity of the solution, and, moreover, all tautomeric forms of the compounds show different affinities to various cyclodextrins. Copyright © 2006 Society of Chemical Industry
EPRI to estimate the in vivo intracerebral reducing ability in adolescent rats subjected to neonatal isolation
Authors: Yokoyama Hidekatsu , Morinobu Shigeru , Ueda Yuto 
Published: March 2006

AbstractPurposeTo estimate the in vivo intracerebral reducing ability after acute stress in adolescent rats subjected to early neonatal isolation (NI), by performing temporal electron paramagnetic resonance imaging (EPRI) of the brain.Materials and MethodsAn EPRI system operating at an EPR frequency of 700 MHz was used. The intracerebral reducing ability was estimated based on the halflife of the EPR signal of the blood–brain barrier (BBB)‐permeable nitroxide radical. The NI treatment was performed for a period of one hour per day over postnatal days 2–9. Six‐week‐old rats were exposed to acute stress (immobilization for 90 minutes) prior to the EPRI study.ResultsDepletion of the intracerebral reducing ability caused by the acute stress was observed; however, this depletion phenomenon did not occur in animals that were not subjected to NI.ConclusionThe results obtained in this study prove that NI induces cerebral vulnerability to acute stress in adolescence. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Multislice multiecho T2* cardiovascular magnetic resonance for detection of the heterogeneous distribution of myocardial iron overload
Authors: Pepe Alessia , Positano Vincenzo , Santarelli Maria Filomena , Sorrentino Fortunato , Cracolici Eliana , De Marchi Daniele , Maggio Aurelio , Midiri Massimo , Landini Luigi , Lombardi Massimo 
Published: March 2006

AbstractPurposeTo assess the tissue iron concentration of the left ventricle (LV) using a multislice, multiecho T2* MR technique and a segmental analysis.Materials and MethodsT2* multiecho MRI was performed in 53 thalassemia major patients. Three short‐axis views of the LV were obtained and analyzed with custom‐written software. The myocardium was automatically segmented into 12 segments. The T2* value on each segment as well as the global T2* value were calculated. Cine dynamic images were also obtained to evaluate biventricular function parameters by quantitative analysis.ResultsFor the T2* global value, the coefficient of variation (CoV) for intra‐/interobserver and interstudy reproducibility was 3.9% (r = 0.98), 5.5% (r = 0.98), and 4.7% (r = 0.99) respectively. Three groups were identified based on analysis of myocardial T2*: homogeneous (21%), heterogeneous (38%), and no myocardial iron overload (41%). The mean serum ferritin, liver iron concentration, and urinary iron excretion were significantly different among the groups. We did not find significant differences among groups in biventricular function. There was a correlation between the global T2* value and the T2* value in the mid‐ventricular septum (r = 0.95, P < 0.0001).ConclusionMultislice multiecho T2* MRI provides a noninvasive, fast, reproducible means of assessing myocardial iron distribution. The single measurement of mid‐septal T2* correlated well with the global T2* value. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Breath‐hold 3D steady‐state free precession coronary MRA compared with conventional X‐ray coronary angiography
Authors: Cheng Liuquan , Gao Yuangui , Guaricci Andrea I. , Mulukutla Suresh , Sun Wei , Sheng Fugeng , Foo Thomas K. , Prince Martin R. , Wang Yi 
Published: March 2006

AbstractPurposeTo evaluate the use of breath‐hold three‐dimensional (3D) steady‐state free precession (SSFP) coronary magnetic resonance angiography (MRA) in patients with coronary artery disease (CAD) in comparison with conventional coronary x‐ray angiography (XRA).Materials and MethodsTwenty‐eight patients with suspected CAD were examined with the use of a breath‐hold 3D‐SSFP‐MRA sequence and conventional XRA. To assess the accuracy of MRA, two clinicians who were blinded to patient information independently reviewed the MRA and XRA data, which were presented in a randomized order. To identify discrepancies between MRA and XRA, and assess features of coronary lesions on MRA, two additional clinicians examined MRA and XRA data that were presented side by side, divided into proximal, mid, and distal segments, and compared them segment by segment.ResultsThe sensitivity and specificity for diagnosing significant coronary stenoses (>50% diameter narrowing) were 64% and 94%, respectively. At sites of coronary lesions identified on XRA, bright signals and enlarged vessel profiles, in addition to the characteristic narrow lumen, were frequently observed on MRA.ConclusionBreath‐hold SSFP coronary MRA has good specificity but inconclusive sensitivity in diagnosing significant coronary stenoses, and provides important image features for depicting coronary lesions. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
The multiple pathways of high performing groups: the interaction of social networks and group processes
Authors: Shah Priti Pradhan , Dirks Kurt T. , Chervany Norman 
Published: March 2006

AbstractThis study examines how both strong and weak relationship groups (groups with numerous, intense internal friendship ties and few, less intense internal friendship ties respectively) achieve high performance when utilizing strategies that capitalize on the strengths and minimizing the weaknesses associated with their internal social structure. We examine the interactions of groups' internal friendship networks with their external network structures (external ties) and internal intragroup conflict (constructive controversy). The results of a study using survey, archival and interview data on 35 groups of MBA students indicated that internal friendship networks interacted with constructive controversy and external networks to determine when groups would achieve superior performance. High performing strong relationship groups engaged in greater constructive controversy than low performing strong relationship groups, while constructive controversy appeared to have minimal effect on the performance of weak relationship groups. High performing weak relationship groups had fewer external bridging ties to other groups when compared to low performing weak relationship groups, while external bridging ties appeared to have minimal effect on the performance of strong relationship groups. Copyright © 2006 John Wiley & Sons, Ltd.
Work performance, affective commitment, and work motivation: the roles of pay administration and pay level
Authors: Kuvaas Bård 
Published: March 2006

AbstractThe purpose of this study was to investigate employee attitudes and behaviors among knowledge workers under different forms of pay administration and pay levels. To examine these issues, I collected data from two business units in a large Norwegian multinational company with pay plans combining individual and collective performance and behaviors as the foundations for individual bonuses; one with two collective components (profit and behavior of the unit and the organization) and one with an individual component in addition to the two collective components. After controlling for organizational tenure, education, gender, perceived unit support, perceptions of distributive and procedural justice, and type of pay plan, the key findings are that base pay level, but not bonus level, was positively related to both self‐reported work performance and affective unit commitment, and that these relationships were partly mediated by intrinsic motivation. Furthermore, moderation analyses revealed that the relationships between bonus level and the outcome variables were not affected by type of pay plan. Implications and directions for future research on pay in knowledge intensive organizations are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Evidence for influence of anthropogenic surface processes on lower tropospheric and surface temperature trends
Authors: De Laat A. T. J. , Maurellis A. N. 
Published: March 2006

AbstractIn de Laat and Maurellis (2004), a new framework was introduced in the form of a spatial‐thresholding trend technique for analyzing the correlation between anthropogenic surface processes (e.g. changes in land use, albedo, soil moisture, groundwater levels, solar absorption by soot or energy consumption) and lower tropospheric and surface temperature trends for the period 1979–2001. In situ measured surface and satellite‐measured lower tropospheric temperature trends were shown to be higher in the vicinity of industrialized regions, while such higher trends were not found in enhanced greenhouse gas (GHG) climate model simulations of temperature. It was suggested that surface and lower tropospheric temperature trends appeared to be influenced by anthropogenic non‐GHG processes on the earth's surface.In this paper, we verify the robustness of the thresholding technique and confirm our earlier conclusions on the basis of an extended analysis and two additional data sets. We confirm the presence of a temperature change–industrialization correlation by analyzing the data with an additional statistical method and further confirm the absence of the above correlation in climate model simulations of enhanced GHG warming. Our findings thus provide an important test of climate model performance on regional scales.These findings suggest that over the last two decades non‐GHG anthropogenic processes have also contributed significantly to surface temperature changes. We identify one process that potentially could contribute to the observed temperature patterns, although there certainly may be other processes involved. Copyright © 2006 Royal Meteorological Society.