bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spatial/temporal correlation of BOLD and optical intrinsic signals in humans
Authors: Pouratian Nader , Sicotte Nancy , Rex David , Martin Neil A. , Becker Donald , Cannestra Andrew F. , Toga Arthur W. 
Published: August 2002

AbstractComparing the BOLD signal with electrophysiological maps and other perfusion‐dependent signals, such as the optical intrinsic signal (OIS), within subjects should provide insight into the etiology of the BOLD signal. Tongue activations were compared in five human subjects using BOLD fMRI, 610‐nm OIS, and the electrocortical stimulation map (ESM). Robust fMRI activations centered on the lateral inferior aspect of the central sulcus and extended into pre‐ and post‐central gyri, adjacent to ESM tongue loci. OIS and fMRI maps colocalized, although optical responses were spatially larger (P < .001 across multiple thresholds) and contained more gyral components. The timecourses of the fMRI and OIS signals were similar, appearing within 2.5 s and peaking 6–8 s after task onset. Although many processes contribute to increased 610‐nm reflectance, optical spectroscopy and fluorescent dye imaging suggest that a significant part of this signal is due to a concomitant decrease in deoxyhemoglobin and increase in oxyhemoglobin concentrations. The spatial/temporal correlation of BOLD and the positive 610‐nm response within subjects suggests that the two signals may share similar etiologies. The OIS/fMRI inconsistencies may be due to cell swelling and light‐scattering contributions to OIS and fMRI sensitivity. This study also demonstrates that fMRI maps do not precisely colocalize with ESM, rather they emphasize changes in adjacent venous/sulcal structures. Magn Reson Med 47:766–776, 2002. © 2002 Wiley‐Liss, Inc.
MR temperature measurement in liver tissue at 0.23 T with a steady‐state free precession sequence
Authors: Germain D. , Vahala E. , Ehnholm G.J. , Vaara T. , Ylihautala M. , Savart M. , Laurent A. , Tanttu J. , Saint‐Jalmes H. 
Published: August 2002

AbstractMRI can be used for monitoring temperature during a thermocoagulation treatment of tumors. The aim of this study was to demonstrate the suitability of a 3D steady‐state free precession sequence (3D Fast Imaging with Steady‐State Precession, 3D TrueFISP) for MR temperature measurement at 0.23 T, and to compare it to the spin‐echo (SE) and spoiled 3D gradient‐echo (3D GRE) sequences. The optimal flip angle for the TrueFISP sequence was calculated for the best temperature sensitivity in the image signal from liver tissue, and verified from the images acquired during the thermocoagulation of excised pig liver. Factors influencing the accuracy of the measured temperatures are discussed. The TrueFISP results are compared to the calculated values of optimized SE and 3D GRE sequences. The accuracy of TrueFISP in the liver at 0.23 T, in imaging conditions used during thermocoagulation procedures, is estimated to be ±3.3°C for a voxel of 2.5 × 2.5 × 6 mm3 and acquisition time of 18 s. For the SE and GRE sequences, with similar resolution and somewhat longer imaging time, the uncertainty in the temperature is estimated to be larger by a factor of 2 and 1.2, respectively. Magn Reson Med 47:940–947, 2002. © 2002 Wiley‐Liss, Inc.
Time‐dependent effects of hormone‐deprivation therapy on prostate metabolism as detected by combined magnetic resonance imaging and 3D magnetic resonance spectroscopic imaging
Authors: Mueller‐Lisse Ullrich G. , Swanson Mark G. , Vigneron Daniel B. , Hricak Hedvig , Bessette André , Males Ryan G. , Wood Penelope J. , Noworolski Susan , Nelson Sarah J. , Barken Israel , Carroll Peter R. , Kurhanewicz John 
Published: August 2002

AbstractCombined MRI and 3D spectroscopic imaging (MRI/3D‐MRSI) was used to study the metabolic effects of hormone‐deprivation therapy in 65 prostate cancer patients, who underwent either short, intermediate, or long‐term therapy, compared to 30 untreated control patients. There was a significant time‐dependent loss of the prostatic metabolites choline, creatine, citrate, and polyamines during hormone‐deprivation therapy, resulting in the complete loss of all observable metabolites (total metabolic atrophy) in 25% of patients on long‐term therapy. The amount and time‐course of metabolite loss during therapy significantly differed for healthy and malignant tissues. Citrate levels decreased faster than choline and creatine levels during therapy, resulting in an increase in the mean (choline + creatine)/citrate ratio with duration of therapy. Due to a loss of all MRSI detectable citrate, this ratio could not be used to identify cancer in 69% of patients on long‐term therapy. In the absence of citrate, however, residual prostate cancer could still be detected by elevated choline levels (choline/creatine ratio ≥1.5), or the presence of only choline in the proton spectrum. The loss of citrate and the presence of total metabolic atrophy correlated roughly with decreasing serum prostatic specific antigen levels with increasing therapy. In summary, MRI/3D‐MRSI provided both a measure of residual cancer and a time‐course of metabolic response following hormone‐deprivation therapy. Magn Reson Med 46:49–57, 2001. © 2001 Wiley‐Liss, Inc.
Pharmacokinetics and enhancement patterns of macromolecular MR contrast agents with various sizes of polyamidoamine dendrimer cores
Authors: Sato Noriko , Kobayashi Hisataka , Hiraga Akira , Saga Tsuneo , Togashi Kaori , Konishi Junji , Brechbiel Martin W. 
Published: August 2002

AbstractFour macromolecular contrast agents are synthesized to visualize small vessels by MRI using generation‐3 (G3D), ‐4 (G4D), ‐5 (G5D), and ‐6 (G6D) polyamidoamine dendrimers conjugated to chelated gadolinium (Gd). The pharmacokinetics, enhancement patterns, and the ability of these constructs to visualize fine vessels is evaluated by dynamic MRI in relationship to their size. Gd‐G6D and ‐G5D exhibit a prolonged high vascular (ventricular) signal intensity (SI) with high ventricle‐to‐organ SI ratios. The initial high vascular SI with Gd‐G4D decreases to a value as low as that obtained with Gd‐G3D and Gd‐dimeglumine‐diethylenetriaminepentaacetic acid (Gd‐DTPA). Gd‐G5D, ‐G4D, and ‐G3D show high renal SIs, and Gd‐DTPA prominently enhances the skin. Gd‐G6D and ‐G5D present fine vasculature significantly more clearly than Gd‐G3D and ‐DTPA (P < 0.005). As the molecular size increases, the excretion of the 153Gd‐conjugates is retarded. In conclusion, Gd‐G6D and ‐G5D are retained in the blood and present fine vessels with high quality and detail, and should be adequate for visualizing small tumor vasculature. Magn Reson Med 46:1169–1173, 2001. © 2001 Wiley‐Liss, Inc.
Laboratory diagnosis of metabolic myopathies
Authors: Vladutiu Georgirene D. 
Published: August 2002

AbstractThe metabolic myopathies are a heterogeneous group of disorders inherited by a variety of modes that include gene defects in both the nuclear and mitochondrial genomes. Many factors impact on the expression of the pathogenic mutations that cause these disorders including genetic background, environmental factors, and coexisting disorders. Molecular technology has greatly improved the ability to make definitive diagnoses in many of the metabolic myopathies in the last decade and particularly has demonstrated that the wide diversity in the severity of mutations contributes to understanding genotype–phenotype correlations. In some cases, molecular testing obviates the necessity to perform an invasive muscle biopsy. However, it is also clear that the diagnostic yield from molecular testing is incomplete and particularly low among the mitochondrial myopathies as a group, ranging from ∼6% to 19% in well‐classified high‐risk groups. Therefore, it is often essential to combine clinical, biochemical, histopathologic, and molecular data for each patient in order to arrive at a definitive diagnosis. The approach to the laboratory diagnosis of metabolic myopathies is described emphasizing both noninvasive and invasive testing, highlighting the molecular methodologies with the benefits and disadvantages of each technology, and documenting how to determine whether patients have coexisting disorders. © 2002 Wiley Periodicals, Inc. Muscle Nerve 25: 000–000, 2002
Localization of ulnar neuropathy with conduction block across the elbow
Authors: Herrmann David N. , Preston David C. , McIntosh Kristi A. , Logigian Eric L. 
Published: August 2002

AbstractWe performed short segment incremental stimulation on 13 consecutive patients with ulnar neuropathy across the elbow (UNE) and conduction block. Conduction block occurred proximal to the medial epicondyle in 62%, at the epicondyle in 23%, and below the elbow in 15%. The ulnar nerve may be more prone to external compression above the elbow than previously recognized. Short segment incremental studies are useful to identify conduction block above the elbow in such patients. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 698–700, 2001
Response to high‐intensity eccentric muscle contractions in persons with myopathic disease
Authors: Kilmer David D. , Aitkens Susan G. , Wright Nancy C. , McCrory Megan A. 
Published: August 2002

AbstractAlthough the response to intense eccentric muscle contractions is well described in normal subjects, concern exists about possible untoward effects in persons with myopathic diseases. We investigated 14 subjects with slowly progressive muscular dystrophies including myotonic muscular dystrophy (n = 9), facioscapulohumeral dystrophy (n = 2), limb‐girdle syndrome (n = 2), and Becker muscular dystrophy (n = 1). Control subjects consisted of 18 able‐bodied persons. Subjects performed two sets of eight maximal‐effort eccentric repetitions of the elbow flexors, with measurement of maximal concentric strength, serum creatine kinase, resting and flexed arm angle, arm circumference, and soreness at days 0, 3, and 7. Although the myopathic group had less initial strength, both groups demonstrated a similar response to the protocol over 7 days. Both groups had a significant rise in serum creatine kinase, which was still elevated at 7 days (P < 0.05). The control group demonstrated a slightly greater injury response in terms of soreness, resting and flexed arm angles, and arm swelling. Both groups of subjects appeared to respond similarly to an acute bout of eccentric contractions. However, the potential long‐term effects of this type of exercise in persons with myopathic diseases remains unknown. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1181–1187, 2001
Inflammatory myopathy associated with mixed connective tissue disease and scleroderma renal crisis
Authors: Greenberg Steven A. , Amato Anthony A. 
Published: August 2002

AbstractMixed connective tissue disease is a rheumatological syndrome with neuromuscular manifestations that may include inflammatory myopathy and carpal tunnel syndrome. We report a patient who presented with an inflammatory myopathy and bilateral carpal tunnel syndrome prior to the diagnosis of a connective tissue disorder. Early in the course of treatment, a syndrome of acute renal failure developed. Knowledge of this syndrome, scleroderma renal crisis, and its possible relation to corticosteroid treatment is important to clinicians involved in the management of patients with inflammatory myopathies. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1562–1566, 2001
Isolated brachialis wasting: An unusual presentation of neuralgic amyotrophy
Authors: Watson Bradley V. , Rose‐Innes Andrew , Engstrom John W. , Brown John D. 
Published: August 2002

AbstractAlthough neuralgic amyotrophy can selectively affect discrete components of the brachial plexus including individual peripheral nerves, involvement of an individual nerve fascicle is rare. Discrete fascicular musculocutaneous neuropathy as a manifestation of neuralgic amyotrophy has not previously been reported to our knowledge. We report two cases of otherwise typical neuralgic amyotrophy with isolated brachialis muscle wasting. Abnormal spontaneous activity, motor unit remodeling, or both, was observed only in the brachialis muscle. Lateral antebrachial cutaneous nerve conduction studies were normal. These cases serve to broaden the spectrum of the clinical presentation of neuralgic amyotrophy. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1699–1702, 2001
Solution of the unsaturated soil moisture equation using repeated transforms
Authors: Fityus S. G. , Smith D. W. 
Published: August 2002

AbstractAn alternative method of solution for the linearized ‘theta‐based’ form of the Richards equation of unsaturated flow is developed in two spatial dimensions. The Laplace and Fourier transformations are employed to reduce the Richards equation to an ordinary differential equation in terms of a transformed moisture content and the transform variables, s and ξ. Separate analytic solutions to the transformed equation are developed for initial states which are either in equilibrium or dis‐equilibrium. The solutions are assembled into a finite layer formulation satisfying continuity of soil suction, thereby facilitating the analysis of horizontally stratified soil profiles. Solution techniques are outlined for various boundary conditions including prescribed constant moisture content, prescribed constant flux and flux as a function of moisture change. Example solutions are compared with linearized finite element solutions. The agreement is found to be good. An adaptation of the method for treating the quasilinearized Richards equation with variable diffusivity is also described. Comparisons of quasilinear solutions with some earlier semi‐analytical, finite element and finite difference results are also favourable. Copyright © 2001 John Wiley & Sons, Ltd.
A simple linear time algorithm for finding a maximum independent set of circular arcs using intervals alone
Authors: Manacher Glenn K. , Mankus Terrance A. 
Published: August 2002

AbstractWe exhibit an algorithm for finding a maximum independent set (MIS) for n presorted, unweighted circular arcs in time 0(n). Unlike previous algorithms, this is achieved by means of trivial postprocessing of the output of a straightforward algorithm for finding an MIS for a set of unweighted intervals. © 2002 Wiley Periodicals, Inc.
Minimum linear gossip graphs and maximal linear (Δ, k)‐gossip graphs
Authors: Fraigniaud Pierre , Peters Joseph G. 
Published: August 2002

AbstractGossiping is an information dissemination problem in which each node of a communication network has a unique piece of information that must be transmitted to all other nodes using two‐way communications between pairs of nodes along the communication links of the network. In this paper, we study gossiping using a linear‐cost model of communication which includes a start‐up time and a propagation time which is proportional to the amount of information transmitted. A minimum linear gossip graph is a graph (modeling a network), with the minimum possible number of links, in which gossiping can be completed in minimum time under the linear‐cost model. For networks with an even number of nodes, we prove that the structure of minimum linear gossip graphs is independent of the relative values of the start‐up and unit propagation times. We prove that this is not true when the number of nodes is odd. We present four infinite families of minimum linear gossip graphs. We also present minimum linear gossip graphs for all even numbers of nodes n ≤ 32 except n = 22. A linear (Δ, k)‐gossip graph is a graph with maximum degree Δ in which gossiping can be completed in k rounds with minimum propagation time. We present three infinite families of maximal linear (Δ, k)‐gossip graphs, that is, linear (Δ, k)‐gossip graphs with a maximum number of nodes. We show that not all minimum broadcast graphs are maximal linear (Δ, k)‐gossip graphs. © 2001 John Wiley & Sons, Inc.
The capacitated arc routing problem with intermediate facilities
Authors: Ghiani Gianpaolo , Improta Gennaro , Laporte Gilbert 
Published: August 2002

AbstractThis article introduces the Capacitated Arc Routing with Intermediate Facilities (CARPIF), a variant of the classical Capacitated Arc Routing Problem (CARP) in which the vehicle may unload or replenish at intermediate facilities. Two lower bounds are developed for the CARPIF: The first is based on the Rural Postman Problem (RPP) and the second one uses a relaxation of an integer linear formulation of the problem. Two upper bounds are also developed, based on the solution of an RPP and of a CARP. Computational results on a set of benchmark instances confirm the quality of the proposed bounds. © 2001 John Wiley & Sons, Inc.
GABA influences the development of the ventromedial nucleus of the hypothalamus
Authors: Dellovade Tammy L. , Davis Aline M. , Ferguson Carolyn , Sieghart Werner , Homanics Gregg E. , Tobet Stuart A. 
Published: August 2002

AbstractThe region that becomes the ventromedial nucleus of the hypothalamus (VMH) is surrounded by cells and fibers containing immunoreactive gamma‐aminobutyric acid (GABA) by embryonic day 13 (E13), several days before the nucleus emerges in Nissl stains. As GABA plays many roles during neural development, we hypothesized that it influences VMH development, perhaps by providing boundary information for migrating neurons. To test this hypothesis we examined the VMH in embryonic mice in which the β3 subunit of the GABAA‐receptor, a receptor subunit that is normally highly expressed in this nucleus, was disrupted by gene targeting. In β3 −/− embryos the VMH was significantly larger, and the distribution of cells containing immunoreactive estrogen receptor‐α was expanded compared to controls. Using in vitro brain slices from wild‐type C57BL/6J mice killed at E15 we found that treatment with the GABAA antagonist bicuculline increased the number of cells migrating per video field analyzed in the VMH. In addition, treatment with either bicuculline or the GABAA agonist muscimol altered the orientation of cell migration in particular regions of this nucleus. These data suggest that GABA is important for the organization of cells during VMH formation. © 2001 John Wiley & Sons, Inc. J Neurobiol 49: 264–276, 2001
Short‐ and long‐chain natural polyamines play specific roles in adult cricket neuroblast proliferation and neuron differentiation in vitro
Authors: Cayre Myriam , Malaterre Jordane , Strambi Colette , Charpin Pierre , Ternaux Jean‐Pierre , Strambi Alain 
Published: August 2002

AbstractIn the house cricket (Acheta domesticus) mushroom bodies, neurogenesis still occurs during adulthood. Using in vitro approaches, the respective roles of natural polyamines in neurogenesis were examined. Mushroom body neuroblast proliferation was assayed in organotypic culture using 5‐bromo, 2′‐deoxyuridine labeling. The number of labeled cells was significantly increased when putrescine was added to culture medium, whereas spermidine and spermine supplementation did not alter cell proliferation. Conversely, in vitro morphometric studies on mushroom body neurons cultured in a defined medium showed that putrescine addition failed to alter any morphological character of these interneurons, whereas addition of the long‐chain polyamines, spermidine and spermine, stimulated neuron differentiation. These two polyamines significantly increased total neurite length; moreover, spermidine‐treated cells exhibited more branches than the controls. The present data demonstrate that putrescine has a mitogenic effect on mushroom body neuronal precursors, and that spermidine and spermine, which failed to induce neuroblast proliferation, act on neuronal differentiation, inducing neurite outgrowth. Our results indicate that short‐ and long‐chain polyamines play specific roles during neurogenesis, and provide a basis for further studies on neuronal precursor proliferation and differentiation. © 2001 John Wiley & Sons, Inc. J Neurobiol 48: 315–324, 2001
Computation and presentation of graphs displaying closure hierarchies of Jordan and Kronecker structures
Authors: Elmroth Erik , Johansson Pedher , Kågström Bo 
Published: August 2002

AbstractStratiGraph, a Java‐based tool for computation and presentation of closure hierarchies of Jordan and Kronecker structures is presented. The tool is based on recent theoretical results on stratifications of orbits and bundles of matrices and matrix pencils. A stratification reveals the complete hierarchy of nearby structures, information critical for explaining the qualitative behaviour of linear systems under perturbations. StratiGraph facilitates the application of these theories and visualizes the resulting hierarchy as a graph. Nodes in the graph represent orbits or bundles of matrices or matrix pencils. Edges represent covering relations in the closure hierarchy. Given a Jordan or Kronecker structure, a user can obtain the complete information of nearby structures simply by mouse clicks on nodes of interest. This contribution gives an overview of the StratiGraph tool, presents its main functionalities and other features, and illustrates its use by sample applications. Copyright © 2001 John Wiley & Sons, Ltd.
Sparse self‐stress matrices for the finite element force method
Authors: Soyer E. , Topcu A. 
Published: August 2002

AbstractA basic problem in the finite element force method is that of obtaining a sparse and banded self‐stress matrix and a sparse and banded structure flexibility matrix.Traditionally the self‐stress matrix is obtained through the application of algebraic procedures to the equilibrium matrix. The self‐stress matrix for an indeterminate structure is not unique, and it is possible to obtain another self‐stress matrix from an existing one through algebraic operations and grouping of redundants. The purpose of this paper is to describe and test an algorithm, called REDUC, which combines the vectors of the self‐stress matrix obtained from the LU procedure of the force method. The rows of the transpose of this matrix are combined by using a special form of the Gaussian elimination technique. A plane frame example is presented to demonstrate the algorithm at work. The algorithm REDUC is applied to a plane truss and physical interpretation of the resulting self‐stress matrix highlights the grouping of redundants, improved sparsity and bandwidth. Improvements in the conditioning and bandwidth of the structure flexibility matrix are also observed. The algorithm yields results similar to those of the turn‐back LU procedure, but requires less computation time and programming effort. Copyright © 2001 John Wiley & Sons, Ltd.
Quadrilateral elements for the solution of elasto‐plastic finite strain problems
Authors: César de Sá José M. A. , Areias Pedro M. A. , Natal Jorge Renato M. 
Published: August 2002

AbstractIn this paper two plane strain quadrilateral elements with two and four variables, are proposed. These elements are applied to the analysis of finite strain elasto‐plastic problems. The elements are based on the enhanced strain and B‐bar methodologies and possess a stabilizing term. The pressure and dilatation fields are assumed to be constant in each element's domain and the deformation gradient is enriched with additional variables, as in the enhanced strain methodology. The formulation is deduced from a four‐field functional, based on the imposition of two constraints: annulment of the enhanced part of the deformation gradient and the relation between the assumed dilatation and the deformation gradient determinant. The discretized form of equilibrium is presented, and the analytical linearization is deduced, to ensure the asymptotically quadratic rate of convergence in the Newton–Raphson method. The proposed formulation for the enhanced terms is carried out in the isoparametric domain and does not need the usually adopted procedure of evaluating the Jacobian matrix in the centre of the element. The elements are very effective for the particular class of problems analysed and do not present any locking or instability tendencies, as illustrated by various representative examples. Copyright © 2001 John Wiley & Sons, Ltd.