bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spedding Award Lecture. Exploratory Synthesis of Reduced Rare‐Earth‐Metal Halides, Chalcogenides, Intermetallics. New Compounds, Structures, and Properties
Authors: Corbett John D. 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Candida antarctica Lipase B: An Ideal Biocatalyst for the Preparation of Nitrogenated Organic Compounds
Authors: Gotor‐Fernandez Vicente , Busto Eduardo , Gotor Vicente 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Organocatalytic Direct Asymmetric α‐Heteroatom Functionalization of Aldehydes and Ketones
Authors: Marigo Mauro , Joergensen Karl Anker 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Excitonic Coupling in Covalently Linked Multiporphyrin Systems by Matrix Diagonalization
Authors: Yoon Zin Seok , Yoon Min‐Chul , Kim Dongho 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Rational Design of Molecular Switches and Sensors from Their Basic Building Blocks
Authors: Moonen Nicolle N. P. , Flood Amar H. , Fernandez Juan M. , Stoddart J. Fraser 
Published: August 2006

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structural and functional growth in self‐reproducing cellular automata
Authors: Bilotta Eleonora , Pantano Pietro 
Published: August 2006

AbstractIn this article, we analyze the dynamics of change in two‐dimensional self‐reproducers, identifying the processes that drive their evolution. We show that changes in self‐reproducers structure and behavior depend on their genetic memory. This consists of distinct yet interlinked components determining their form and function. In some cases these components degrade gracefully, changing only slightly; in others the changes destroy the original structure and function of the self‐reproducer. We sketch these processes at the genotype and the phenotype level—showing that they follow distinct trajectories within mutation space and quantifying the degree of change produced by different trajectories. We show that changes in structure and behavior depend on the interplay between the genotype and the phenotype. This determines universal structures, from which it is possible to construct a great number of self‐reproducing systems, as we observe in biology. Creative processes of change produce divergent and/or convergent methods for the generation of self‐reproducers. Divergence involves the creation of completely new information convergence involves local change and specialization of the structures concerned. © 2006 Wiley Periodicals, Inc. Complexity 11: 12–29, 2006
From plasmacytoid to dendritic cell: Morphological and functional switches during plasmacytoid pre‐dendritic cell differentiation
Authors: Soumelis V. , Liu Y‐J. 
Published: August 2006

AbstractPlasmacytoid dendritic cell precursors (pDC/IPC) are the major producers of type I interferon and have the unique ability to link innate and adaptive immunity. After producing large amounts of type I IFN in response to microbial stimulation, they can differentiate into DC capable of stimulating naive T cells and modulate the adaptive immune response. In this review, we focus on the transition between these two highly specialized cell types, which is accompanied by major morphological, structural and functional changes, many of which remain to be fully characterized. We propose that the plasmacytoid and dendritic morphologies correspond to distinct differentiation states and effector functions.
Use of the Connectivity of Runoff Model (CRUM) to investigate the influence of storm characteristics on runoff generation and connectivity in semi‐arid areas
Authors: Reaney S. M. , Bracken L. J. , Kirkby M. J. 
Published: August 2006

AbstractMuch attention has been given to the surface controls on the generation and transmission of runoff in semi‐arid areas. However, the surface controls form only one part of the system; hence, it is important to consider the effect that the characteristics of the storm event have on the generation of runoff and the transmission of flow across the slope. The impact of storm characteristics has been investigated using the Connectivity of Runoff Model (CRUM). This is a distributed, dynamic hydrology model that considers the hydrological processes relevant to semi‐arid environments at the temporal scale of a single storm event. The key storm characteristics that have been investigated are the storm duration, rainfall intensity, rainfall variability and temporal structure. This has been achieved through the use of a series of defined storm hydrographs and stochastic rainfall. Results show that the temporal fragmentation of high‐intensity rainfall is important for determining the travel distances of overland flow and, hence, the amount of runoff that leaves the slope as discharge. If the high‐intensity rainfall is fragmented, then the runoff infiltrates a short distance downslope. Longer periods of high‐intensity rainfall allow the runoff to travel further and, hence, become discharge. Therefore, storms with similar amounts of high‐intensity rainfall can produce very different amounts of discharge depending on the storm characteristics. The response of the hydrological system to changes in the rainfall characteristics can be explained using a four‐stage model of the runoff generation process. These stages are: (1) all water infiltrating, (2) the surface depression store filling or emptying without runoff occurring, (3) the generation and transmission of runoff and (4) the transmission of runoff without new runoff being generated. The storm event will move the system between the four stages and the nature of the rainfall required to move between the stages is determined by the surface characteristics. This research shows the importance of the variable‐intensity rainfall when modelling semi‐arid runoff generation. The amount of discharge may be greater or less than the amount that would have been produced if constant rainfall intensity is used in the model. Copyright © 2006 John Wiley & Sons, Ltd.
A review of the National Groundwater Monitoring Network in Korea
Authors: Lee Jin‐Yong , Yi Myeong‐Jae , Yoo Young‐Kwon , Ahn Kyung‐Hwan , Kim Gyoo‐Bum , Won Jong‐Ho 
Published: August 2006

AbstractThe drastic expansion of cities and the rapid economic growth in Korea have caused dramatic increases to demand from groundwater supplies for drinking, domestic, agricultural and industrial water usage. The Ministry of Construction and Transportation and the Korea Water Resources Corporation have constructed and operated the National Groundwater Monitoring Network (NGMN) throughout the country since 1995. The NGMN, an official project establishing a total of 320 groundwater monitoring stations, was completed in 2005. Each national groundwater monitoring station serves as a baseline and primary station to monitor long‐term general trends in water‐level fluctuations and in groundwater quality. The present NGMN and its monitoring capabilities were evaluated to enhance the efficiency of groundwater monitoring and to meet the new societal conditions. Based on reviews and evaluations, some suggestions and recommendations are made with regard to improvements of the national network, including the installation of rainfall gauges in groundwater monitoring stations, gathering groundwater data every hour instead of every 6 h as at present, involving major cations and anions in the regular and periodic chemical analyses, regular periodic analyses of collected groundwater data, and construction of 199 additional groundwater monitoring stations to supplement the existing groundwater monitoring network. Copyright © 2006 John Wiley & Sons, Ltd.
Cytoskeletal response of microvessel endothelial cells to an applied stress force at the submicrometer scale studied by atomic force microscopy
Authors: Ma Wanyun , Sun Yunxu , Han Dong , Chu Weiguo , Lin Danying , Chen Dieyan 
Published: August 2006

AbstractCytoskeleton fibers form an intricate three‐dimensional network to provide structure and function to microvessel endothelial cells. During accommodation to blood flowing, stress fiber bundles become more prominent and align with the direction of blood flow. This network either mechanically resists the applied shear stress (lateral force) or, if deformed, is dynamically remodeled back to a preferred architecture. However, the detailed response of these stress fiber bundles to applied lateral force at submicrometer scales are as yet poorly understood. In our in vitro study, the tip, topography probe in lateral force microscopy of atomic force microscopy, acted as a tool for exerting quantitative vertical and lateral force on the filaments of the cytoskeleton. Moreover, the authors developed a formula to calculate the value of lateral force exerted on every point of the filaments. The results show that cytoskeleton fibers of healthy tight junctions in rat cerebral microvessel endothelial cells formed a cross‐type network, and were reinforced and elongated in the direction of scanning under lateral force of 15–42 nN. Under peroxidation (H2O2 of 300 μmol/L), the cytoskeleton remodeled at intercellular junctions, and changed over the meshwork structures into a dense bundle, that redistributed the stress. Once mechanical forces were exerted on an area, the cells shrank and lost morphologic tight junctions. It would be useful in our understanding of certain pathological processes, such as cerebral ischemia/reperfusion injury, which maybe caused by biomechanical forces and which are overlooked in current disease models. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Real‐time automated tracking and trapping system for sperm
Authors: Z. Shi Linda , Nascimento Jaclyn , Chandsawangbhuwana Charlie , Berns Michael W. , Botvinick Elliot L. 
Published: August 2006

AbstractWe have developed a microscope system for real‐time single sperm tracking with an automated laser tweezers escape power assay. Phase contrast images of swimming sperm are digitized to the computer at video rate. The custom algorithm creates a region of interest centered about a sperm in response to a mouse click and performs all subsequent tasks autonomously. Microscope stage movement responds to feedback from video analysis of swimming sperm to center the sperm with respect to the field of view. For escape power assays, sperm are automatically relocated to the laser trap focus where they are held for a user‐defined duration at fixed power, or held as laser power is gradually reduced. The sperm's position is automatically monitored to measure the laser power at which the sperm escapes the trap. Sperm are tracked for extended durations before and after laser trap experiments. Motility measurements including the curvilinear velocity and the absolute position of the sperm relative to the cell chamber are calculated and written to the hard drive at video rate. Experimental throughput is increased over 30 times compared to off‐line data analysis. The efficacy of the “track and trap” algorithm is validated through examples and comparisons with the manually collected data. Microsc. Res. Tech., 2006. © 2006 Wiley‐Liss, Inc.
Blood attenuation with SSFP‐compatible saturation (BASS)
Authors: Lin Hung‐Yu , Dale Brian M. , Flask Chris A. , Duerk Jeffrey L. 
Published: August 2006

AbstractPurposeTo investigate a rapid flow‐suppression method for improving the contrast‐to‐noise ratio (CNR) between the vessel wall and the lumen for cardiovascular imaging applications.Materials and MethodsIn this study a new dark‐blood steady‐state free precession (SSFP) sequence utilizing two excitation pulses per TR was developed. The first pulse is applied immediately adjacent to the slice of interest, while the second is a conventional slice‐selective pulse designed to excite an SSFP signal for the static spins in the slice of interest. The slice‐selective pulse is followed by fully refocused gradients along all three imaging axes over each TR. The signal amplitude (SA) from the moving spins excited by the “saturation” pulse is attenuated since they are not fully refocused at the TE.ResultsThis work provides confirmation, by both simulation and experiments, that modest adaptations of the basic True‐FISP structure can limit unwanted “bright blood” signal within the vessels while simultaneously preserving the contrast and speed advantages of this well‐established rapid imaging method.ConclusionAnimal imaging trials confirm that dark‐blood contrast is achieved with the BASS sequence, which substantially reverses the lumen‐to‐muscle CNR of a conventional True‐FISP “bright blood” acquisition from 14.77 (bright blood) to −13.96 (dark blood) with a modest increase (24.2% of regular TR of SSFP for this implementation) in acquisition time to accommodate the additional slab‐selective excitation pulse and gradient pulses. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
In vivo R1‐enhancement mapping of canine myocardium using ceMRI with Gd(ABE‐DTTA) in an acute ischemia‐reperfusion model
Authors: Kiss P. , Suranyi P. , Simor T. , Saab‐Ismail N.H. , Elgavish A. , Hejjel L. , Elgavish G.A. 
Published: August 2006

AbstractPurposeTo demonstrate the usefulness of normalized ΔR1 (ΔR1n) mapping in myocardial tissue following the administration of the contrast agent (CA) Gd(ABE‐DTTA).Materials and MethodsIschemia‐reperfusion experiments were carried out in 11 dogs. The method exploited the relatively long tissue lifetime of Gd(ABE‐DTTA), and thus no fast R1 measurement technique was needed. Myocardial perfusion was determined with colored microspheres (MP).ResultsWith varying extent of ischemia, impaired wall motion (WM) and lower ΔR1n values were detected in the ischemic sectors, as opposed to the nonischemic sectors where normal WM and higher ΔR1n were observed. Based on the ΔR1n, data from the myocardial perfusion assay and the ΔR1n maps were compared in the ischemic sectors. A correlation analysis of these two parameters demonstrated a significant correlation (R = 0.694, P < 0.005), validating the ΔR1n‐mapping method for the quantitation of ischemia. Similarly, pairwise correlations were found for the MP, ΔR1n, and wall thickening (WT) values in the same areas. Based on the correlation between ΔR1n and MP, ΔR1n maps calculated with a pixel‐by‐pixel resolution can be converted to similarly high‐resolution myocardial perfusion maps.ConclusionThese results suggest that the extent of the severity of ischemia can be quantitatively represented by ΔR1n maps obtained in the presence of our CA. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Model‐free parameters from dynamic contrast‐enhanced‐MRI: Sensitivity to EES volume fraction and bolus timing
Authors: Jesberger John A. , Rafie Niusha , Duerk Jeffrey L. , Sunshine Jeffrey L. , Mendez Matthew , Remick Scot C. , Lewin Jonathan S. 
Published: August 2006

AbstractPurposeTo quantify the unknown relative sensitivities of semiquantitative measures from dynamic contrast‐enhanced (DCE) MRI to variations in the volume fraction Ve of the extravascular extracellular space (EES), and the duration of the contrast injection.Materials and MethodsTissue‐uptake curves were simulated across various values of F, PS, Ve, and bolus timings, with and without additive noise and at different image reacquisition rates. From each, the peak of the first derivative (Gpeak), the total uptake after the rapid first phase (CE), and the IAUC were calculated and plotted against F for each experimental condition. Relationships between each measure and the corresponding quantitative measure Ktrans were also examined, particularly for linearity.ResultsThe highest sensitivity to flow was achieved for shorter bolus timings for Gpeak, CE, and IAUC. Gpeak and IAUC were most linearly related to Ktrans. The sensitivity to Ve was lowest for Gpeak, followed by IAUC and CE. Long sampling intervals resulted in severe underestimation of Gpeak, while IAUC was unaffected provided that the limits of integration were properly applied. Gpeak could not be properly calculated in the presence of noise without a prior smoothing of the acquired curves, while IAUC was again unaffected by noise.ConclusionGpeak and IAUC are both useful model‐free analogs of blood flow (i.e., Ktrans) for pre‐ and posttreatment comparisons. Gpeak may be the better choice in cases where larger changes in Ve are likely, but only if sufficient noise reduction and fast image sampling are applied. If Ve is expected to remain stable, IAUC is superior to Gpeak by virtue of its stability in the face of noise and more reliable estimation over a wider range of sampling rates. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Longitudinal assessment of Alzheimer's β‐amyloid plaque development in transgenic mice monitored by in vivo magnetic resonance microimaging
Authors: Braakman Niels , Matysik Jörg , van Duinen Sjoerd G. , Verbeek Fons , Schliebs Reinhard , de Groot Huub J.M. , Alia A. 
Published: August 2006

AbstractPurposeTo assess the development of β‐amyloid (Aβ) plaques in the brain with age in the transgenic mouse model of Alzheimer's disease (AD) pathology by in vivo magnetic resonance microimaging (μMRI).Materials and MethodsLive transgenic mice (Tg2576) and nontransgenic littermates (control) were studied at regular intervals between the ages of 12 and 18 months. Plaques were visualized using a T2‐weighted rapid acquisition with relaxation enhancement (RARE) sequence. Changes in T2 relaxation times were followed using a multislice multiecho (MSME) sequence. Plaque load and numerical density in MR images were calculated using SCIL image software.ResultsAβ plaques were clearly detected with the T2‐weighted RARE sequence in the hippocampal and cortical regions of the brain of Tg2576 mice but not in control mice. Following the plaque development in the same animals with age showed that plaque area, number, and size increased markedly, while T2 relaxation time showed a decreasing trend with age.ConclusionThese results demonstrate that μMRI is a viable method for following the development of Aβ plaques in vivo, and suggest that this method may be feasible for assessing the effect of therapeutic interventions over time in the same animals. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Dobutamine cardiovascular magnetic resonance: A review
Authors: Mandapaka Sangeeta , Hundley William Gregory 
Published: August 2006

AbstractDobutamine cardiovascular magnetic resonance (DCMR) is useful for identifying myocardial ischemia and viability in patients with known or suspected coronary artery disease (CAD). This article reviews the performance and utility of DCMR, its association with dobutamine stress echocardiography (DSE), and areas of active investigative research. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Development of a novel optimized breathhold technique for myocardial T2 measurement in thalassemia
Authors: He Taigang , Gatehouse Peter D. , Anderson Lisa J. , Tanner Mark , Keegan Jennifer , Pennell Dudley J. , Firmin David N. 
Published: August 2006

AbstractPurposeTo develop a reproducible fast spin‐echo (FSE) technique for accurate myocardial T2 measurement with application to iron overload assessment in thalassemia.Materials and MethodsAn FSE sequence was developed to permit acquisition of multiple TE images in one breathhold (BH‐FSE). A dynamic black‐blood scheme was introduced to better cancel blood signal. A nonselective refocusing train was also adopted to suppress stimulated echoes. The optimized technique was tested on phantoms and then applied to 10 normal volunteers and 10 thalassemia patients. Interstudy reproducibility was measured on all the 20 subjects.ResultsThe mean difference in T2 values was 1.7% from phantom experiments between BH‐FSE and the conventional spin‐echo (SE) technique. High contrast BH‐FSE images were acquired from human subjects, with minimal stimulated echoes and effective blood suppression (P = 0.0005). The coefficient of variation for interstudy reproducibility was 4.3%. T2 values from thalassemia patients were substantially lower than those from the normal subjects (45.2 ± 26.1 msec vs. 56.9 ± 8.4ms, P = 0.02).ConclusionThe dynamic black‐blood T2 sequence is a fast reproducible acquisition that compares favorably with conventional techniques, is robust to motion artifacts, and yields high blood‐myocardium contrast. This technique may provide a useful tool in thalassemia and other scenarios requiring myocardial T2 quantification. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Adaptive bilateral breast MRI using projection reconstruction time‐resolved imaging of contrast kinetics
Authors: Ramsay E. , Causer P. , Hill K. , Plewes D. 
Published: August 2006

AbstractPurposeTo introduce a bilateral implementation of an adaptive imaging technique in which both dynamic and high resolution breast MR images are acquired simultaneously.Materials and MethodsAdaptive three‐dimensional bilateral breast imaging in the sagittal plane was achieved by combining two elements: a projection reconstruction time‐resolved imaging of contrast kinetics (PR‐TRICKS) k‐space trajectory and a slab interleaved sequence that imaged alternate breasts every TR. A pilot study was performed to evaluate image quality and contrast uptake behavior, using eight patients with previously identified benign lesions.ResultsAdaptive reconstruction demonstrated breast lesions in all eight women with similar image quality and signal‐to‐noise ratio (SNR) to Cartesian images with comparable imaging parameters. Contrast enhancement curves covering the entire postinjection time period were obtained from the dynamic images and in one case compared to previous enhancement profiles from a conventional Cartesian trajectory.ConclusionBilateral dynamic and high spatial resolution images with high SNR can be achieved in a clinically feasible manner, providing both kinetic and morphologic analysis with a single data set. This may obviate the need for multiple MRI examinations for a thorough breast MRI workup. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.