bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lipid content in the musculature of the lower leg assessed by fat selective MRI: Intra‐ and interindividual differences and correlation with anthropometric and metabolic data
Authors: Machann Jürgen , Bachmann Oliver P. , Brechtel Klaus , Dahl Dominik B. , Wietek Beate , Klumpp Bernhard , Häring Hans‐U. , Claussen Claus D. , Jacob Stephan , Schick Fritz 
Published: February 2003

AbstractPurposeTo assess the muscular lipid content (LC) in different muscle groups of the lower leg by a magnetic resonance imaging technique working with chemical shift selective excitation, and comparison with anthropometric and metabolic data.Materials and MethodsExaminations were performed in 67 volunteers (54 male/13 female, age 29 ± seven years) on a 1.5 T whole body imager, applying a highly selective spectral‐spatial technique for fat selective MRI. LC was measured in six calf muscles and correlated with body mass index (BMI), percent body fat (PFAT), and insulin sensitivity (IS) of the subjects.ResultsMean muscular LC of all subjects was between 2.0% (Tibialis posterior [TP]) and 3.8% (Peroneus muscles) with female subjects showing a significantly higher LC in all muscle groups (P < 0.05 each). LCs correlated moderately with BMI (R between 0.39 [TP] and 0.53 [GM]) and with PFAT (R between 0.38 [TP] and 0.62 [GM]). Insulin‐resistant subjects showed slightly but not significantly increased LC compared to insulin‐sensitive subjects in BMI‐matched subgroups.ConclusionThe fat‐selective MRI technique allows a reliable non‐invasive measure of muscular lipids – even in muscle groups with inherent low LC – within a relatively short measurement time of about three minutes. The presented data reveal interesting interrelationships between LC and anthropometric and metabolic data, and therefore provide new insight into muscular fat metabolism. J. Magn. Reson. Imaging 2003;17:350–357. © 2003 Wiley‐Liss, Inc.
Time‐resolved contrast‐enhanced pulmonary MR angiography using sensitivity encoding (SENSE)
Authors: Ohno Yoshiharu , Kawamitsu Hideaki , Higashino Takanori , Takenaka Daisuke , Watanabe Hirokazu , van Cauteren Marc , Fujii Masahiko , Hatabu Hiroto , Sugimura Kazuro 
Published: February 2003

AbstractPurposeTo evaluate the relationship between gadolinium concentration and signal‐to‐noise ratio (SNR) on sensitivity encoding (SENSE) images, and determine the appropriate bolus injection protocol for visualizing pulmonary circulation.Materials and MethodsEighteen different gadolinium concentration phantoms (0, 0.01, 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5, 2.0, 5.0, 10.0, 20.0, 30.0, 50.0, and 100.0 mmol/L) were analyzed to determine the relationship between gadolinium concentration and SNR on SENSE images in a phantom study. In an in vivo study, 3 mL (protocol A) or 6 mL (protocol B) of Gd‐DTPA BMA at 3 mL/second, and 5 mL of Gd‐DTPA BMA at 5 mL/second (protocol C) were administered to eight normal volunteers for contrast‐enhanced (CE) pulmonary MR angiography (MRA) with SENSE. The peak SNRs of pulmonary parenchyma and the difference in SNR between pulmonary artery (PA) and pulmonary vein (PV) at peak SNR in the PA were statistically evaluated.ResultsFor each flip angle at each gadolinium concentration, the SNRs and contrast‐to‐noise ratios (CNRs) of the SENSE images were significantly lower than those acquired with a nonparallel imaging technique (P < 0.05). The peak SNR of the pulmonary parenchyma, and differences in SNR between the PA and PV at the peak SNR of the PA obtained with a 5‐mL/second bolus injection protocol were found to be significantly higher than those obtained with other protocols (P < 0.05).Conclusion3D‐CE‐MRA using SENSE demonstrated linearity between gadolinium concentration and SNR, and resulted in MRA with high spatial and temporal resolution with the aid of a sharp bolus injection protocol. J. Magn. Reson. Imaging 2003;17:330–336. © 2003 Wiley‐Liss, Inc.
Normal human left and right ventricular dimensions for MRI as assessed by turbo gradient echo and steady‐state free precession imaging sequences
Authors: Alfakih Khaled , Plein Sven , Thiele Holger , Jones Tim , Ridgway John P. , Sivananthan Mohan U. 
Published: February 2003

AbstractPurposeTo establish normal ranges of left ventricular (LV) and right ventricular (RV) dimensions as determined by the current pulse sequences in cardiac magnetic resonance imaging (MRI).Materials and MethodsSixty normal subjects (30 male and 30 female; age range, 20–65) were examined; both turbo gradient echo (TGE) and steady‐state free precession (SSFP) pulse sequences were used to obtain contiguous short‐axis cine data sets from the ventricular apex to the base of the heart. The LV and RV volumes and LV mass were calculated by modified Simpson's rule.ResultsNormal ranges were established and indexed to both body surface area (BSA) and height. There were statistically significant differences in the measurements between the genders and between TGE and SSFP pulse sequences. For TGE the LV end‐diastolic volume (EDV)/BSA (mL/m2) in males was 74.4 ± 14.6 and in females was 70.9 ± 11.7, while in SSFP in males it was 82.3 ± 14.7 and in females it was 77.7 ± 10.8. For the TGE the LV mass/BSA (g/m2) in males was 77.8 ± 9.1 and in females it was 61.5 ± 7.5, while in SSFP in males it was 64.7 ± 9.3 and in females it was 52.0 ± 7.4. For TGE the RV EDV/BSA (mL/m2) in males was 78.4 ± 14.0 and in females it was 67.5 ± 12.7, while in SSFP in males it was 86.2 ± 14.1 and in females it was 75.2 ± 13.8.ConclusionWe have provided normal ranges that are gender specific as well as data that can be used for age‐specific normal ranges for both SSFP and TGE pulse sequences. J. Magn. Reson. Imaging 2003;17:323–329. © 2003 Wiley‐Liss, Inc.
Investigating the stimulus‐dependent temporal dynamics of the BOLD signal using spectral methods
Authors: Müller Karsten , Mildner Toralf , Lohmann Gabriele , von Cramon D. Yves 
Published: February 2003

AbstractPurposeTo compare several spectral parameters using different durations of visual hemifield stimulation in order to explore the different temporal behavior of the blood oxygenation‐level dependent (BOLD) signal in various brain regions.Materials and MethodsSpectral methods were applied to three different groups of subjects with visual stimulation lasting 6, 12, and 30 seconds. Furthermore, diffusion weighting was applied in an interleaved way. The core of the data processing was the computation of the spectral density matrix using the multidimensional weighted covariance estimate. Spectral parameters of coherence and phase shift were computed.ResultsThe correlation between signal changes and phase shifts was dependent on the duration of the visual stimulation. The shorter the duration of visual stimulation, the stronger the correlation between percentage signal change and phase shift.ConclusionThe experiments with short and long stimuli differed mainly in the distribution of the activated voxels in the plane of percentage signal change and phase shift. It was revealed that the height of the signal change depends on the phase shift, whereas the diffusion weighting has no influence. J. Magn. Reson. Imaging 2003;17:375–382. © 2003 Wiley‐Liss, Inc.
Imaging the physical and morphological properties of a multi‐zone young articular cartilage at microscopic resolution
Authors: Xia Yang , Moody Jonathan B. , Alhadlaq Hisham , Hu Jiani 
Published: February 2003

AbstractPurposeTo characterize a number of physical and morphologic properties of young articular cartilage. These properties include the anisotropy of T2relaxation, optical retardation, orientation of the collagen fibrils, total thickness of the tissue, number of histologic sub‐zones in the tissue, width of individual sub‐zones, and correlation between the depths of the local T2maxima and the local retardation minima.Materials and MethodsMicroscopic magnetic resonance imaging (μMRI) and polarized light microscopy (PLM) were used to examine three side‐by‐side specimens from a humeral head of a three‐month‐old beagle that exhibited a unique topographic heterogeneity from three‐zones centrally to multi‐zone peripherally.ResultsThe centrally located specimen showed that the collagen fibrils across the tissue depth have a pattern of the classic three histologic sub‐zones (tangential, transitional, and radial). A much more complicated multi‐zone structure was found in the specimen located peripherally, with a second transitional zone and a second tangential zone located at the deep part of the tissue. We also showed that the orientation of the collagen fibrils that form the cocoon‐shaped territorial matrix surrounding the clusters of chondrocytes can be imaged by our PLM technique.ConclusionThe results from the young animal in this report, together with our observations from older animals, demonstrate that MRI and PLM can be used to study the epiphyseal expansion of cartilage in young animals during its growth and subsequent loss in older animals. An illustrative model for the structure of collagen fibrils in a humeral head is suggested as an extension to the classic three‐zone model for young articular cartilage. J. Magn. Reson. Imaging 2003;17:365–374. © 2003 Wiley‐Liss, Inc.
1H magnetic resonance spectroscopy in human hydrocephalus
Authors: Braun Kees P.J. , Gooskens Rob H.J.M. , Vandertop W. Peter , Tulleken Cees A.F. , van der Grond Jeroen 
Published: February 2003

AbstractPurposeTo evaluate cerebral metabolism in clinical hydrocephalus with 1H magnetic resonance spectroscopy (MRS).Materials and MethodsIn 24 children and adults with progressive, arrested, or normal pressure hydrocephalus, long‐echo time 1H MR spectra were acquired from periventricular white matter and intraventricular cerebrospinal fluid (CSF). Metabolite ratios, and the presence of lactate, were compared with 38 age‐matched controls.ResultsMetabolite ratios of patients were within the 95% confidence interval (CI) of controls. A small lactate resonance was detected in 20% of control and hydrocephalic subjects. Lactate was consistently visible in CSF spectra, though lactate concentrations were normal. The CSF lactate T2 was long in comparison with the known intracellular metabolite T2 relaxation times. In three neonates with hydrocephalus and spina bifida, 3‐hydroxybutyrate was detected in CSF in vivo.ConclusionWithin the limits of the present methods, 1H MRS could not detect cerebral metabolic abnormalities in human hydrocephalus and provided no additional diagnostic information. The long T2 of lactate in CSF explains its high visibility. Hence, the detection of lactate in spectra acquired from voxels that contain CSF does not necessarily imply cerebral ischemia. J. Magn. Reson. Imaging 2003;17:291–299. © 2003 Wiley‐Liss, Inc.
BOLD‐fMRI response vs. transcranial magnetic stimulation (TMS) pulse‐train length: Testing for linearity
Authors: Bohning Daryl E. , Shastri Ananda , Lomarev Mikhail P. , Lorberbaum Jeffrey P. , Nahas Ziad , George Mark S. 
Published: February 2003

AbstractPurposeTo measure motor and auditory cortex blood oxygenation level‐dependent (BOLD) functional magnetic resonance imaging (fMRI) response to impulse‐like transcranial magnetic stimulation (TMS) pulses as a function of train length.Materials and MethodsInterleaved with fMRI at 1.5 T, TMS pulses 0.3‐msec long were applied at 1 Hz to the motor cortex area for thumb. Six subjects were studied in a TR = 1 second session administering trains of 1, 2, 4, 8, and 16 pulses, and a TR = 3 seconds session administering trains of 1, 2, 4, 8, 16, and 24 pulses. A simple hemodynamic model with finite recovery and saturation was used to quantitatively characterize the BOLD‐fMRI response as a function of train length.ResultsIn both the activations directly induced in motor cortex by TMS and the indirect activations in auditory cortex caused by the sound of the TMS coil firing, the BOLD‐fMRI responses to multiple pulses were well described by a summation of single‐pulse impulse functions.ConclusionUp to 24 discrete pulses, BOLD‐fMRI response to 1 Hz TMS in both motor cortex and auditory cortex were consistent with a linear increase in amplitude and length with train length, possibly suggesting that stimuli of 1 to 2 seconds may be too long to represent impulses. J. Magn. Reson. Imaging 2003;17:279–290. © 2003 Wiley‐Liss, Inc.
Does job insecurity lead to impaired well‐being or vice versa? Estimation of cross‐lagged effects using latent variable modelling
Authors: Hellgren Johnny , Sverke Magnus 
Published: February 2003

AbstractAlthough research suggests that job insecurity is associated with impaired employee well‐being, there is insufficient empirical evidence to draw any causal inferences since most studies are cross‐sectional and thus do not control for previous levels of health symptoms. We used longitudinal questionnaire data to investigate the direction of the relationship between job insecurity and health complaints. After controlling for prior levels of mental and physical health complaints and five other variables that could potentially confound the results (gender, age, organizational tenure, family status, and education), the results of latent variable modelling showed that the cross‐lagged effect of job insecurity on mental health complaints, one year later, was significant whereas the reversed effects of mental and physical health complaints on subsequent insecurity were non‐significant. However, there was no significant cross‐lagged effect of job insecurity on physical health complaints. The results provide empirical support for the theoretical notion that job insecurity leads to health complaints, and imply that prior levels of health should be taken into consideration in order to explain the relative effect of perceived job insecurity on the physical and mental health of the workforce. Copyright © 2003 John Wiley & Sons, Ltd.
Where intrinsic job satisfaction fails to work: national moderators of intrinsic motivation
Authors: Huang Xu , Van De Vliert Evert 
Published: February 2003

AbstractThis study sought for national characteristics that moderate the individual‐level relationship between job characteristics and job satisfaction. Data from two distinct questionnaire surveys administered to 107,292 employees in 49 countries was analyzed by employing multilevel modeling. Results showed that the link between intrinsic job characteristics and job satisfaction is stronger in richer countries, countries with better governmental social welfare programs, more individualistic countries, and smaller power distance countries. By contrast, extrinsic job characteristics are strongly and positively related to job satisfaction in all countries. In addition, we found that intrinsic job characteristics tend to produce motivating satisfaction in countries with good governmental social welfare programs irrespective of the degree of power distance, while they do not tend to work so in countries with poor governmental social welfare programs as well as a large power distance culture. Socio‐economic and cultural approaches to explaining cross‐national variation in work motivation are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Experimental study of SAR reduction on commercial products and shielding materials in mobile phone applications
Authors: Fung L. C. , Leung S. W. , Chan K. H. 
Published: February 2003

AbstractThere has been a recent increase in public concern regarding human safety due to the exposure of humans to radio frequency (RF) electromagnetic energy radiated by mobile phone handsets. This paper presents an experimental study of the effectiveness of various commercially available specific absorption rate (SAR) reduction products and shielding materials that can be externally attached to the handsets. The results have indicated that the effectiveness of both the SAR reduction products and the shielding materials in reducing SARs are generally below 10%. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 419–422, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10780
A printed diversity dual‐band monopole antenna for WLAN operation in the 2.4‐ and 5.2‐GHz bands
Authors: Wu Tzuenn‐Yih , Fang Shyh‐Tirng , Wong Kin‐Lu 
Published: February 2003

AbstractA novel printed diversity dual‐band monopole antenna integrated on a PCMCIA network card for WLAN operation in the 2.4‐ and 5.2‐GHz bands is proposed. The antenna comprises two substantially orthogonal printed monopoles with a straight strip of longer length for the lower‐mode operation (2.4‐GHz band) and a protruded strip of shorter length for the upper‐mode operation (5.2‐GHz band). In addition, the two monopoles are placed symmetrically with respect to a protruded ground plane of double‐T shape, which leads to good isolation obtained between the antenna's two feeding ports. With the system switching between the antenna's two ports, maximum signal strength for WLAN operation can be obtained, and system performance can be enhanced. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 436–439, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10784
Initial coding results with a millimeter‐wave six‐port QPSK receiver
Authors: Song Zhiyan , Tatu Serioja , Soleymani Mohammad Reza , Wu Ke , Bosisio Renato G. 
Published: February 2003

AbstractIn this paper, error‐control coding is used with a six‐port direct‐digital QPSK receiver [1] in an AWGN channel. The direct‐conversion wideband six‐port millimeter wave receiver proposed herein meets the needs of MMIC mass‐market wireless communications. Convolutional code and Turbo code are used as the channel codes for the first time in this type of receiver. The BER results for the convolutional code, turbo code, and the uncoded system in the six‐port receiver, are presented at a bit rate of 1 Mbps. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 465–467, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10791
Multiple‐frequency photonic bandgap microstrip structures based on defects insertion
Authors: Griol A. , Mira D. , Martinez A. , Marti J. 
Published: February 2003

AbstractIn this paper, microstrip photonic bandgap structures based on etching a nonperiodic pattern of circles in the ground plane of a microstrip line are investigated. Three topologies based on placing two defects in a periodic circle pattern, with a different spacing between them for each structure, are considered and their responses are compared. Multiple‐frequency and bandwidth‐tuned bandgaps are obtained. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 479–481, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10795
A fast synthesis algorithm of adaptive beams for smart antennas
Authors: Li Jinhua , Jin Ronghong , Sheng Yanci 
Published: February 2003

AbstractAn amplitude approaching algorithm (AAA) for the pattern synthesis of adaptive arrays is presented in this paper. Furthermore, the algorithm is amended by the Newton downhill method. Simulations show that the main lobe and side lobe can be controlled efficiently, and the algorithm converges more quickly and steadily. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 503–507, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10804
Identification of estrogen‐regulated genes in the mouse uterus using a delayed‐implantation model
Authors: Lee Sukwon , Lee Seung‐Ah , Shim Chanseob , Khang Inkoo , Lee Kyung‐Ah , Park Young‐Mee , Kang Byung‐Moon , Kim Kyungjin 
Published: February 2003

AbstractGonadal steroid hormones are known to modulate the implantation of the blastocyst, but how the controlling genetics are regulated remains largely unknown. Using a delayed‐implantation model, we examined estrogen‐regulated genes (ERGs) in the mouse uterus using the differential‐display reverse transcription‐polymerase chain reaction (DD RT‐PCR). Pregnant mice were ovariectomized and injected daily with progesterone (P, 1 mg/mouse), followed by a single injection of estrogen (E, 200 ng/mouse); 24 or 48 hr later, total RNA was extracted from the uterus. Reverse Northern analysis verified the expression patterns of 36 clones out of thousands of RNA species. Only five clones had mRNA levels that were modified, whereas other mRNAs were unchanged or not detectable. Sequence analysis of these, using the Basic Local Alignment Search Tool (BLAST) service, revealed that four of these clones were novel; one clone, designated ERG10, was found to be the mouse homologue of that deleted in oral cancer DOC‐1. DOC‐1 mRNA was detected all tissues examined, but only in the uterus and cervix was markedly increased 12 hr after E administration, it returned to basal level by 48 hr. One of the novel genes, designated ERG8, had three different forms of mRNAs and was expressed ubiquitously in all examined tissues. In the uterus, the mRNA level of ERG8 also increased 12 hr after E administration. These results suggest that during the implantation process, E differentially regulates several genes depending on cell type. Uterine‐specific induction of newly found genes, such as ERG8 and 10, by E appears to be important for the early implantation process. Mol. Reprod. Dev. 64: 405–413, 2003. © 2003 Wiley‐Liss, Inc.
Alterations and reversibility in the chromatin, cytoskeleton and development of pig oocytes treated with roscovitine
Authors: Ju Jyh‐Cherng , Tsay Chih , Ruan Chi‐Wai 
Published: February 2003

AbstractGerminal vesicle (GV) breakdown in mammalian oocytes is regulated by the activation of maturation promoting factor (MPF). We investigated a specific cdc2 kinase inhibitor, roscovitine, to maintain pig oocytes in the GV stage. Cumulus‐oocyte complexes (COCs) were aspirated from slaughterhouse ovaries and cultured for 44 hr in NCSU#23 medium containing different levels of roscovitine (0, 10, 20, 30, 40, 50 μM in Experiment 1 and 0, 40, 60, 80, 100, 120 μM in Experiment 2). The COCs were cultured for another 44 hr after removal of the chemical. Twenty oocytes in each group were fixed at 44 hr for immunocytochemical labeling of the cytoskeleton and the rest (∼20/group) were fixed at the end of 88 hr after culture. Results showed that the inhibition of the oocyte in the GV stage was not effective when 10–50 μM (Experiment 1) of roscovitine were used (19–34%). When oocytes were released from the inhibitor, similar proportions (70–83%) of oocytes were observed in the MII or advanced stages among treatments. However, when higher concentrations of roscovitine were used (Experiment 2), significantly greater inhibitory effect was observed at the levels of 80–120 μM with 83–91% oocytes being blocked in the GV stage when compared to the control (9%) and the 40–60 μM (27–43%) groups (P < 0.05). Although 15–21% of the oocytes showed abnormal MII morphology with aberrant meiotic spindles and/or formation of cytoplasmic microtubules, a substantial number of oocytes resumed meiosis and reached MII stage at 44 hr after removal of this chemical. In Experiment 3, different concentrations of roscovitine (0, 20, 40, and 80 μM) were tested to examine the length of intervals (0, 11, 22, 33, and 44 hr) for an effective inhibition. Results showed that the inhibitory effect was significantly more prominent at 22 hr than that at 33 and 44 hr after roscovitine treatment in all treatment groups (P < 0.05). This study demonstrated that roscovitine‐treated oocytes resumed meiosis after removal of the inhibitor. This could provide flexibility for studying porcine oocyte development and embryo cloning and may have application in other species. Mol. Reprod. Dev. 64: 482–491, 2003. © 2003 Wiley‐Liss, Inc.