bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sexual dimorphism in the neuronal circuits of the quail preoptic and limbic regions
Authors: Panzica Giancarlo , Viglietti‐Panzica Carla , Balthazart Jacques 
Published: August 2002

AbstractA sexually dimorphic nucleus is located in the preoptic area of Japanese quail and plays a key role in the activation of male copulatory behavior. The medial preoptic nucleus (POM) is significantly larger in adult male than in adult female quail. Its volume is steroid‐sensitive in adulthood and consequently decreases after castration but is restored to normal levels by a treatment with exogenous testosterone. This volumetric difference appears to result only from a sex difference in the adult hormonal milieu and is not affected by embryonic treatments that permanently modify sexual behavior (no organizational effects). In contrast, some cytoarchitectonic features of the POM such as the size of neurons in the dorso‐lateral part of nucleus appear to be irreversibly affected by embryonic steroids. The POM is characterized by the presence of a wide variety of neurotransmitters, neuropeptides, and receptors and can be specifically identified by the presence of a dense cluster of aromatase‐immunoreactive cells, by a high density of neurotensin‐immunoreactive cells and fibers and by a dense vasotocinergic innervation. Some of these neurochemical markers of the dimorphic nucleus are themselves modulated by steroids. Many of these neurochemical changes appear to play a causal role in the control of male sexual behavior. The quail POM thus represents an excellent model for the analysis of steroid‐induced brain plasticity in a behaviorally relevant context. Microsc. Res. Tech. 54:364–374, 2001. © 2001 Wiley‐Liss, Inc.
Phylogeny of natural cytotoxicity: Cytotoxic activity of coelomocytes of the purple sea urchin, Arbacia punctulata
Authors: Lin Wenyu , Zhang Haiyan , Beck Gregory 
Published: August 2002

AbstractCoelomocyte‐mediated nonspecific cell cytotoxic activity against human and murine target cells by the purple sea urchin Arbacia punctulata was investigated in vitro. Cytotoxic activity toward target cells was shown to be mediated by different coelomocyte populations isolated by discontinuous density gradient centrifugation. The population of phagocytic amebocytes showed the strongest cytotoxic activity and the highest binding to human NK markers by cytometry analysis. Our immunophenotypic studies showed that A. punctulata phagocytic amebocytes are CD14+, CD56+, CD158b+, CD3–, CD4–, CD8–, and CD16–. The cytotoxic activity was independent of experimental incubation temperatures, required viable effector cells, and required cell‐cell contact between the effector and target cells. Sodium azide significantly decreased coelomocyte cytotoxicity, indicating that cytotoxicity is metabolically dependent, and EDTA reduction of cytotoxic activity is consistent with the involvement of divalent cations in the cytotoxic process. These data describe a population of sea urchin coelomocytes (the phagocytic amebocyte) that are CD14+, CD56+, and CD158b+, with cytotoxic activities. J. Exp. Zool. 290:741–750, 2001. © 2001 Wiley‐Liss, Inc.
Landau's inequalities for tournament scores and a short proof of a theorem on transitive sub‐tournaments
Authors: Brualdi Richard A. , Shen Jian 
Published: August 2002

AbstractAo and Hanson, and Guiduli, Gyárfás, Thomassé and Weidl independently, proved the following result: For any tournament score sequence S = (s1, s2, … ,sn) with s1≤s2 ≤ … ≤ sn, there exists a tournament T on vertex set {1,2, …, n} such that the score of each vertex i is si and the sub‐tournaments of T on both the even and the odd indexed vertices are transitive in the given order; that is, i dominates j whenever i > j and i ≡ j (mod 2). In this note, we give a much shorter proof of the result. In the course of doing so, we show that the score sequence of a tournament satisfies a set of inequalities which are individually stronger than the well‐known set of inequalities of Landau, but collectively the two sets of inequalities are equivalent. © 2001 John Wiley & Sons, Inc. J Graph Theory 38: 244–254, 2001
Utopianism in psychology: The case of Wilhelm Reich
Authors: Pietikainen Petteri 
Published: August 2002

AbstractThis article examines utopian elements in Wilhelm Reich's writings in his American phase (1939–1957) in order to illustrate utopian sources of dynamic psychology. Although there are scholars who have used the term “psychological utopia” and applied it to individual thinkers (Reich, Marcuse, Fromm) and to specific psychological disciplines (psychoanalysis, behaviorism, cognitive psychology), the term itself has remained elusive and vague. Furthermore, there have been few attempts to systematically examine utopian elements in twentieth‐century psychology in general and the basic assumptions of psychological utopianism in particular. While pointing out that Reich's orgonomic theories have no scientific merit, this article argues for the relevancy of his ideas for understanding the nature of utopianism in dynamic psychology. © 2002 Wiley Periodicals, Inc.
Enterprise across the digital divide: information systems and rural microenterprise in Botswana
Authors: Duncombe Richard , Heeks Richard 
Published: August 2002

AbstractThis paper focuses on the role of information and information‐handling technologies within the many rural microenterprises that currently lack access to ICTs. On the basis of field research in Botswana, it finds that poor rural entrepreneurs rely heavily on informal, social and local information systems. While highly appropriate in many ways, these systems can also be constrained and insular. Priorities for breaking this insularity will be greater access to shared telephone services. ICTs may play a supplementary role. They will need to be based in intermediary organizations that can provide complementary inputs of finance, skills, knowledge and other resources. Copyright © 2002 John Wiley & Sons, Ltd.
Reproducibility of left ventricular mass measurement using a half‐Fourier black‐blood single‐shot fast spin‐echo sequence within a single breath hold: Comparison with a conventional multiple breath‐hold segmented gradient echo technique in patients
Authors: Vignaux Olivier , Duboc Denis , Coste Joel , Argaud Christophe , Carlier Pierre , Le Roux Patrick , Weber Simon , Legmann Paul 
Published: August 2002

AbstractPurposeTo compare the reproducibility of left ventricular (LV) mass measurements using a black‐blood half‐Fourier single‐shot fast spin‐echo (SSFSE) and a segmented gradient echo magnetic resonance (MR) pulse sequence.Material and MethodsBreath‐hold SSFSE and segmented gradient echo cardiac MR examinations were performed twice in 32 patients and manual detection of the LV endocardium and epicardium was applied by two blinded reviewers. The SSFSE pulse sequence allowed whole‐heart coverage in a single breath hold, while multiple breath holds were required using the segmented gradient echo sequence. Spatial presaturation slabs were used with the SSFSE pulse sequence to reduce the field of view (FOV) and thereby achieve higher spatial resolution.ResultsIntraclass correlation coefficients were higher with the SSFSE pulse sequence than with the segmented gradient echo pulse sequence: intraobserver reproducibility reached 0.999 vs. 0.991; interobserver reproducibility: 0.997 vs. 0.981; and interstudy reproducibility: 0.998 vs. 0.936. These higher levels of reproducibility were confirmed on Bland and Altman plots.ConclusionLV mass measurements can be assessed more reproducibly with the single breath‐hold SSFSE technique than with the standard multiple breath‐hold segmented gradient echo method. J. Magn. Reson. Imaging 2002;15:654–660. © 2002 Wiley‐Liss, Inc.
Measurement of vessel wall strain using cine phase contrast MRI
Authors: Wedding Kristin L. , Draney Mary T. , Herfkens Robert J. , Zarins Christopher K. , Taylor Charles A. , Pelc Norbert J. 
Published: August 2002

AbstractPurposeTo determine the feasibility of using magnetic resonance imaging (MRI) to non‐invasively measure strain in the aortic wall.Materials and MethodsCine phase contrast MRI was used to measure the velocity of the aortic wall and calculate changes in circumferential strain over the cardiac cycle. A deformable vessel phantom was used for initial testing and in vitro validation. Ultrasonic sonomicrometer crystals were attached to the vessel wall and used as a gold standard.ResultsIn the in vitro validation, MRI‐calculated wall displacements were within 0.02 mm of the sonomicrometer measurements when maximal displacement was 0.28 mm. The measured maximum strain in vitro was 0.02. The in vivo results were on the same order as prior results using ultrasound echo‐tracking.ConclusionResults of in vivo studies and measurement of cyclic strain in human thoracic and abdominal aortas demonstrate the feasibility of the technique.J. Magn. Reson. Imaging 2002;15:418–428. © 2002 Wiley‐Liss, Inc.
TrueFISP: Assessment of accuracy for measurement of left ventricular mass in an animal model
Authors: Fieno David S. , Jaffe Wyatt C. , Simonetti Orlando P. , Judd Robert M. , Finn J. Paul 
Published: August 2002

AbstractPurposeTo test the accuracy of a high performance true fast imaging with steady‐state precession (TrueFISP) pulse sequence for the assessment of left ventricular (LV) mass in a large animal model on 1.5‐T scanners.Materials and MethodsWe imaged dogs (N = 10) on a clinical 1.5‐T clinical scanner using electrocardiogram (ECG)‐gated TrueFISP. In all animals, contiguous segmented k‐space cine images were acquired from base to apex (in‐plane resolution 1 × 1 mm2, slice thickness 5 mm, TR = 4.8 msec, TE = 1.6 msec) during repeated breath‐holds. In nine of the 10 animals, single‐shot images gated to end‐diastole were also acquired from base to apex in a single breath‐hold (in‐plane resolution 1 × 1 mm2, slice thickness 5 mm, TR = 3.2 msec, TE = 1.6 msec). After imaging, animals were killed, the left ventricle was isolated, and the true mass of the left ventricle (free wall and septum) was determined. Independently, two observers blinded to the post‐mortem results computed LV masses based on analysis of the magnetic resonance (MR) images.ResultsComparison of the computed LV mass using TrueFISP to the actual mass showed excellent agreement. Cine‐systole was the most accurate technique (mass = 98.6% ± 4.5% actual, bias = 1.2 ± 3.4 g) followed by cine‐diastole (mass = 97.9% ± 5.3% actual, bias = 1.8 ± 4.1 g) and single shot (mass = 94.7% ± 7.9% actual, bias = 4.2 ± 6.3 g). Inter‐ and intra‐observer variabilities were low (5.8% ± 7.1% and 0.4% ± 4.8%, respectively).ConclusionWe conclude that TrueFISP imaging is an accurate, rapid method to determine ventricular mass. In single‐shot mode, TrueFISP requires only one breath‐hold to estimate the mass of the heart within 6% of the actual value, whereas the segmented k‐space implementation measured LV mass to within 3% of the true value. J. Magn. Reson. Imaging 2002;15:526–531. © 2002 Wiley‐Liss, Inc.
Short echo time MR spectroscopic imaging of the lung parenchyma
Authors: Gold Garry E. , Pauly John M. , Leung Ann N. , Block Walter F. , Meyer Craig H. , Sze Raymond , Macovski Albert , Stark Paul 
Published: August 2002

AbstractPurposeTo perform short echo time MR spectroscopic imaging of the lung parenchyma on normal volunteers.Materials and MethodsA short echo time projection‐reconstruction spectroscopic imaging sequence was implemented on a commercial 1.5T whole body MRI scanner. Images and spectra of the lung parenchyma were obtained from five normal volunteers. Breath‐held spectroscopic imaging was also performed.ResultsSpectroscopic imaging of short‐T2* species allows visualization of different anatomic structures based upon their frequency shifts. A characteristic peak from the parenchyma was seen at three ppm from water frequency.ConclusionShort echo time MR spectroscopic imaging of the lung parenchyma was demonstrated in normal volunteers. This method may improve proton imaging of the lungs and add specificity to the diagnosis of pulmonary disease. J. Magn. Reson. Imaging 2002;15:679–684. © 2002 Wiley‐Liss, Inc.
A comparison of conventional spin‐echo and fast spin‐echo in the detection of multiple sclerosis
Authors: Patola Wayne B. , Coulter Bruce A. , Chipperfield Patricia M. , Lingawi Sattam S. 
Published: August 2002

AbstractFast spin‐echo (FSE) pulse sequences enable T2‐weighted imaging in a fraction of the time required for T2‐weighted conventional spin‐echo (CSE) imaging. Due to concerns that the altered contrast characteristics of FSE may interfere with the visualization of multiple sclerosis (MS) lesions, the sensitivity of T2‐weighted FSE sequences was compared to comparably weighted CSE sequences in the imaging of the brain in 100 patients with clinically suspected MS. The proton‐density FSE sequence revealed more MS lesions than its CSE counterpart, while the T2‐weighted CSE sequences were found to be more sensitive than the T2‐weighted FSE sequence. Contrast‐to‐noise ratios and signal‐to‐noise ratios compared favorably between sequences. Overall, there was little difference in the specificity between FSE and CSE in the diagnosis of MS. The higher sensitivity and the reduction in time attainable through the use of FSE warrants its replacement of CSE when imaging the brain in patients with clinically suspected MS. J. Magn. Reson. Imaging 2001;13:657–667. © 2001 Wiley‐Liss, Inc.
Visualization of flow patterns distal to aortic valve prostheses in humans using a fast approach for cine 3D velocity mapping
Authors: Kozerke Sebastian , Hasenkam J. Michael , Pedersen Erik M. , Boesiger Peter 
Published: August 2002

AbstractThe fluid dynamic performance of mechanical heart valves differs from normal valves and thus is considered related to late clinical complications in patients. Since flow patterns evolving around heart valves are complex in space and time, flow visualization based on time‐resolved 3D velocity data might add important information regarding the performance of specific valve designs in vivo. However, previous cine 3D techniques for three‐directional phase‐contrast velocity mapping suffer from long scan duration and therefore might hamper assessment in patients. A hybrid 3D phase‐contrast sequence combining segmented k‐space acquisition with short EPI readout trains is presented with its validation in vitro. The technique was applied to study flow patterns downstream from a bileaflet aortic prosthesis in six patients. Navigator echoes were incorporated for respiratory motion compensation. Before flow visualization, spurious phase errors due to concomitant gradient fields and eddy currents were corrected. Flow visualization was based on particle paths and animated velocity vector plots. Dedicated algorithms for particle path integration were implemented to account for the considerable motion of the ascending aorta during the cardiac cycle. A distinct flow pattern reflecting the valve design was observed closest to the valve during early flow acceleration. Reverse flow occurred adjacent to high velocity jets and above the hinge housings. Later in systole, flow became confined to the central vessel area and reverse flow along the inner aortic curvature developed. Further downstream from the valve, flow patterns varied considerably among patients, indicating the impact of varying aortic anatomy in vivo. It is concluded that MR velocity mapping is a potential tool for studying 3D flow patterns evolving around heart valve prostheses in humans. J. Magn. Reson. Imaging 2001;13:690–698. © 2001 Wiley‐Liss, Inc.
Combined MR imaging and CFD simulation of flow in the human descending aorta
Authors: Wood Nigel B. , Weston Simon J. , Kilner Philip J. , Gosman A. David , Firmin David N. 
Published: August 2002

AbstractA combined MR and computational fluid dynamics (CFD) study is made of flow in the upper descending thoracic aorta. The aim was to investigate further the potential of CFD simulations linked to in vivo MRI scans. The three‐dimensional (3D) geometrical images of the aorta and the 3D time‐resolved velocity images at the entry to the domain studied were used as boundary conditions for the CFD simulations of the flow. Despite some measurement uncertainties, comparisons between simulated and measured flow structures at the exit from the domain demonstrated encouraging levels of agreement. Moreover, the CFD simulation allowed the flow structure throughout the domain to be examined in more detail, in particular the flow separation region in the distal aortic arch and its influence on the downstream flow during late systole. Additional information such as relative pressure and wall shear stress, which could not be measured via MRI, were also extracted from the simulation. The results have encouraged further applications of the methods described. J. Magn. Reson. Imaging 2001;13:699–713. © 2001 Wiley‐Liss, Inc.
Successful treatment of recurrent vulvar intraepithelial neoplasia resistant to interferon and isotretinoin with cidofovir
Authors: Koonsaeng Suphannee , Verschraegen Claire , Freedman Ralph , Bossens Michel , Kudelka Andrzej , Kavanagh John , Sittisomwong Tul , DeClercq Erik , Snoeck Robert 
Published: August 2002

AbstractVulvar intraepithelial neoplasias are difficult to eradicate completely without extensive surgical intervention. Cidofovir, a deoxycytidine monophosphate analog, may have a therapeutic role in this disease. A 43‐year‐old woman with a 20‐year history of genital warts presented with extensive vulvar intraepithelial neoplasia III, and refused surgical resection. Topical cidofovir 1% in Beeler base completely eradicated the lesion. Successive treatment applications, however, were necessary. Cidofovir is a promising topical antiviral compound for HPV induced vulvar intraepithelial neoplasia. J. Med. Virol. 64:195–198, 2001. © 2001 Wiley‐Liss, Inc.
Screening for possible failure of herpes simplex virus PCR in cerebrospinal fluid for the diagnosis of herpes simplex encephalitis
Authors: Puchhammer‐Stöckl Elisabeth , Presterl Elisabeth , Croÿ Cornelia , Aberle Stefan , Popow‐Kraupp Therese , Kundi Michael , Hofmann Hanns , Wenninger Ursula , Gödl Irene 
Published: August 2002

AbstractThe objectives of this study were to evaluate the reliability of herpes simplex virus (HSV) PCR testing in cerebrospinal fluid (CSF) for the detection of herpes simplex encephalitis. This was done by examining retrospectively the clinical follow‐up of a large group of patients tested routinely by HSV‐PCR. In addition, an attempt was made to assess the incidence of herpes simplex encephalitis in a central European population. CSF samples from 1,427 patients from all Vienna hospitals were submitted for HSV‐PCR testing during a period of 4 years and 8 months. Herpes simplex encephalitis was detected by PCR in 12 cases and by serological methods in one additional patient. Retrospective analysis of the course of disease, which was possible in 799 PCR‐negative patients, led to the identification of three additional cases in which herpes simplex encephalitis appears to have occurred despite negative PCR results. Failure of the PCR in these patients is most likely due to the time of obtaining CSF during the course of disease. A high specificity of the assay was demonstrated by the lack of false positive results in any of the 708 cases in which other causes for the neurological symptoms had been identified in the follow‐up. The incidence of herpes simplex encephalitis in the population of Vienna was between 1 case/469,000–577,000 individuals/year. The highest annual incidence was detected in the age group between 3 months and 3 years, which, however, could not be confirmed statistically. J. Med. Virol. 64:531–536, 2001. © 2001 Wiley‐Liss, Inc.
Detection and genotyping of human papillomavirus DNA by SPF10 and MY09/11 primers in cervical cells taken from women attending a colposcopy clinic
Authors: Perrons Chris , Kleter Bernhard , Jelley Rosanne , Jalal Hamid , Quint Wim , Tedder Richard 
Published: August 2002

AbstractHuman papillomavirus (HPV) is the main etiological agent of cervical cancer. There is a large number of HPV genotypes and therefore a need to distinguish the high risk HPV genotypes associated with invasive cancer from the low risk. Because persistence of high risk HPV infection is necessary for progression of a pre‐invasive cervical change one needs to identify the individual genotype to see if it persists. PCR amplification of HPV DNA is described using two consensus primer systems from cervical cells. Amplified HPV DNA was genotyped using a reverse hybridization line probe assay (LiPA). HPV DNA was amplified from 42% of samples by MY09/11 and from 80% by SPF10. In 42 samples HPV DNA was detected by both primer sets and in 38 samples only the SPF10 primers detected HPV DNA. The LiPA detected 21 different HPV genotypes (13 high risk) in this cohort of samples. Forty‐three percent contained a single HPV genotype and 24% contained multiple infections (2–5 genotypes). Overall, high risk HPV genotypes were detected in 48% of the cervical samples, the most frequent types were 16, 18, 31, and 51. The proportion of high risk HPV genotypes increased with more severe cytological abnormalities. This study demonstrates that the SPF10 primer set is more sensitive than the MY09/11 primer set and that genotyping by LiPA tells us if the HPV infection is caused by a high risk type and if the infection is mixed. Additionally LiPA provides information about the individual genotype when looking for persistence of infection. HPV DNA detection and genotyping is therefore a useful tool in the colposcopy clinic, used in conjunction with cytology. J. Med. Virol. 67:246–252, 2002. © 2002 Wiley‐Liss, Inc.
Optical, electrical and thermal analysis for GaN semiconductor lasers
Authors: Hatakoshi Gen‐ichi , Onomura Masaaki , Ishikawa Masayuki 
Published: August 2002

AbstractDevice characteristics of GaN‐based semiconductor lasers have been analysed by numerical calculation. Anti‐guide‐like behaviour of the waveguide mode appears in InGaN laser structures where the cladding layers have insufficient thickness. Such phenomena are peculiar to laser structures with GaN material systems. The layer structure should be designed so as to suppress the anti‐guide mode. Carrier overflow is also a significant problem for GaN lasers. A high acceptor concentration for the p‐type cladding layer and the reduction of the active layer volume have a large effect on the reduction of such carrier overflow. In regard to the temperature characteristics, one of the restricting factors is the use of sapphire substrates which have relatively high thermal resistivity. The maximum operation temperature has been calculated based on the analysis for the thermal resistance of the device. It was shown that reduction in the stripe width as well as reduction in threshold current density and operation voltage is very important for improving the temperature characteristics of GaN semiconductor lasers. Copyright © 2001 John Wiley & Sons, Ltd.