bluuebunny/crossref_metadata_2025 huggingface dataset:
Soil organic carbon stock for reclaimed minesoils in northeastern Ohio
Authors: Shukla M. K. , Lal R.
Published: July 2005

Reclamation of disturbed soils is done with the primary objective of restoring the land for agronomic or forestry land use. Reclamation followed by sustainable management can restore the depleted soil organic carbon (SOC) stock over time. This study was designed to assess SOC stocks of reclaimed and undisturbed minesoils under different cropping systems in Dover Township, Tuscarawas County, Ohio (40°32·33′ N and 81°33·86′ W). Prior to reclamation, the soil was classified as Bethesda Soil Series (loamy‐skeletal, mixed, acid, mesic Typic Udorthent). The reclaimed and unmined sites were located side by side and were under forage (fescue—Festuca arundinacea Schreb. and alfa grass—Stipa tenacissima L.), and corn (Zea mays L.)—soybean (Glycine max (L.) Merr.) rotation. All fields were chisel plowed annually except unmined forage, and fertilized only when planted to corn. The manure was mostly applied on unmined fields planted to corn, and reclaimed fields planted to forage and corn. The variability in soil properties (i.e., soil bulk density, pH and soil organic carbon stock) ranged from moderate to low across all land uses in both reclaimed and unmined fields for 0–10 and 10–20 cm depths. The soil nitrogen stock ranged from low to moderate for unmined fields and moderate to high in some reclaimed fields. Soil pH was always less than 6·7 in both reclaimed and unmined fields. The mean soil bulk density was consistently lower in unmined (1·27 mg m−3 and 1·22 mg m−3) than reclaimed fields (1·39 mg m−3 and 1·34 mg m−3) planted to forage and corn, respectively. The SOC and total nitrogen (TN) concentrations were higher for reclaimed forage (33·30 g kg−1; 3·23 g kg−1) and cornfields (21·22 g kg−1; 3·66 g kg−1) than unmined forage (17·47 g kg−1; 1·98 g kg−1) and cornfield (17·70 g kg−1; 2·76 g kg−1). The SOC stocks in unmined soils did not differ among forage, corn or soybean fields but did so in reclaimed soils for 0–10 cm depth. The SOC stock for reclaimed forage (39·6 mg ha−1 for 0–10 cm and 28·6 mg ha−1 for 10–20 cm depths) and cornfields (28·3 mg ha−1; 32·2 mg ha−1) were higher than that for the unmined forage (22·7 mg ha−1; 17·6 mg ha−1) and corn (21·5 mg ha−1; 26·8 mg ha−1) fields for both depths. These results showed that the manure application increased SOC stocks in soil. Overall this study showed that if the reclamation is done properly, there is a large potential for SOC sequestration in reclaimed soils. Copyright © 2005 John Wiley & Sons, Ltd.
Simulated rainfall evaluation of revegetation/mulch erosion control in the Lake Tahoe basin: 2. Bare soil assessment
Authors: Grismer M. E. , Hogan M. P.
Published: July 2005

Slopes that have been disturbed through roadway, ski slope or other construction often produce more sediment than less disturbed sites. Reduction or elimination of sediment loading from such disturbed slopes to adjacent streams is critical in the Lake Tahoe basin. Here, use of a portable rainfall simulator (RS), described in the first paper of this series, is used to evaluate slope effects on erosion from bare volcanic and granitic soils (road cut and ski run sites) common in the basin in order to establish a basis upon which revegetation treatment comparisons can be made. Rainfall simulations (60 mm h−1, approximating a 100‐year, 15‐minute storm) at each site included multiple replications of bare soil plots as well as some adjacent ‘native’, or relatively undisturbed soils below trees where available. Field measurements of time to runoff, infiltration, runoff, sediment discharge rates, and average sediment concentration were obtained. Laboratory measurements of particle‐size distributions using sieve and laser counting methods indicated that the granitic soils had larger grain sizes than the volcanic soils and that road cut soils of either type also had larger grain sizes than their ski run counterparts. Particle‐size‐distribution‐based estimates of saturated hydraulic conductivity were 5–10 times greater than RS‐determined steady infiltration rates. RS‐measured infiltration rates were similar, ranging from 33–50 mm h−1 for disturbed volcanic soils and 33–60 mm h−1 for disturbed granitic soils. RS‐measured runoff rates and sediment yields from the bare soils were significantly correlated with plot slope with the exception of volcanic road cuts due to the narrow range of road cut slopes encountered. Sediment yields from bare granitic soils at slopes of 28 to 78 per cent ranged from ∼1 to 12 g m−2 mm−1, respectively, while from bare volcanic soils at slopes of 22 to 61 per cent they ranged from ∼3 to 31 g m−2 mm−1, respectively. Surface roughness did not correlate with runoff or erosion parameters, perhaps also as a result of a relatively narrow range of roughness values. The volcanic ski run soils and both types of road cut soils exhibited nearly an order of magnitude greater sediment yield than that from the corresponding native, relatively undisturbed, sites. Similarly, the granitic ski run soils produced nearly four‐times greater sediment concentration than the undisturbed areas. A possible goal of restoration/erosion control efforts could be recreation of ‘native’‐like soil conditions. Copyright © 2005 John Wiley & Sons, Ltd.
C1‐Symmetric Heterocyclic Zirconocenes as Catalysts for Propylene Polymerization, 2
Authors: Resconi Luigi , Guidotti Simona , Camurati Isabella , Frabetti Riccardo , Focante Francesca , Nifant'ev Ilya E. , Laishevtsev Ilya P.
Published: July 2005

Summary: Sixteen C1‐symmetric zirconocene and one hafnocene complexes bearing the 2,5‐R2‐7H‐cyclopenta[1,2‐b:4,3‐b′]dithiophene ligand (R = H, Me, Et, Ph) linked to a substituted indenyl ligand have been synthesized and tested in propylene polymerization. Most of the C1‐symmetric zirconocenes of this type are highly active in propylene polymerization at low MAO/Zr ratios and produce poly(propylene)s (PP) in a broad range of isotacticity and melting points. The molecular weight and crystallinity of the PPs are strongly dependent upon the type of substituents on the indenyl moiety: PPs with Tm between 75 and 156 °C and viscosity average molecular weights between 100 000 and 400 000 have been obtained at 50–70 °C in liquid propylene.

General formula of the indenyl‐based zirconocenes.

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General formula of the indenyl‐based zirconocenes.
Back Cover: Macromol. Rapid Commun. 14/2005
Authors: Lü Kangbo , Yang Decai
Published: July 2005

Back Cover: A bright‐field electron micrograph and its corresponding electron diffraction pattern of recrystallized Cr‐coated (or carbon‐coated) high density polyethylene single crystals, with a heat‐treated temperature as high as 200 °C, indicate that the particle‐coated single crystals can retain their crystal structure after complete melting and subsequent recrystallization. This phenomenon is attributed to a surface fixing effect of vacuum‐evaporated particles on the single crystals. Further details can be found in the Communication by K. Lü and D. Yang on page 1159.
Rheology of Polydisperse Star Polymer Melts: Extension of the Parameter‐Free Tube Model of Milner and McLeish to Arbitrary Arm‐Length Polydispersity
Authors: Slot Johan J. M. , Steeman Paul A. M.
Published: July 2005

Summary: This paper considers the extension of the parameter‐free tube model of Milner and McLeish for stress relaxation in melts of monodisperse star polymers to star polymers whose arms have a continuous molecular weight distribution such as the Flory distribution in the case of star‐nylons and star‐polyesters. Exact expressions are derived for the relaxation spectrum and the relaxation modulus for star polymers having an arbitrary continuous arm‐length distribution. For a Flory distribution a comparison is made with results of dynamic measurements on a melt of 8‐arm poly(ε‐caprolactone) (PCL) stars. An excellent quantitative agreement over a large frequency range is found, however, only if one treats, in contrast with the original parameter‐free tube model approach, the entanglement molecular weight that determines the relaxation spectrum as a fitting parameter independent of the entanglement molecular weight of the linear PCL. This discrepancy is not in anyway related to the polydispersity in arm‐length, but a consequence of the thermorheological complexity of the PCL stars. A similar discrepancy has been observed for hydrogenated polybutadiene stars, as described by Levine and Milner.

Measured and calculated storage moduli G′ as a function of frequency ω.

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Measured and calculated storage moduli G′ as a function of frequency ω.
Relationship between hallucinations, delusions, and rapid eye movement sleep behavior disorder in Parkinson's disease
Authors: Pacchetti Claudio , Manni Raffaele , Zangaglia Roberta , Mancini Francesca , Marchioni Enrico , Tassorelli Cristina , Terzaghi Michele , Ossola Maria , Martignoni Emilia , Moglia Arrigo , Nappi Giuseppe
Published: July 2005

Psychotic symptoms are the main and the most disabling “nonmotor” complications of Parkinson's disease (PD), the pathophysiology of which is poorly recognized. Polysomnographic studies have shown a relationship between visual hallucinations and rapid eye movement (REM) sleep. The objective of this study is to clarify the relationship between psychotic symptoms and REM sleep behavior disorder (RBD) in PD. In a Parkinson's disease outpatient unit, 289 consecutive subjects with idiopathic PD were administered (in the period from January to December 2002) a multiple‐choice questionnaire and structured interview on sleep and mental disorders. RBD was diagnosed in accordance with the minimal diagnostic criteria of the International Classification of Sleep Disorders. Hallucinations and delusional disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders‐IV criteria. The presence or absence of psychotic symptoms, of RBD, and of daytime sleepiness, as well as motor status, cognitive status, and mood were assessed. Approximately 32% (n = 92) of the subjects presented with psychotic disorders; 30% (n = 86) had experienced hallucinations; 2% (n = 6) had delusions without hallucinations. Sixty‐two (72%) hallucinators reported nocturnal hallucinations. A total of 6.6% (n = 19) of the subjects complained of a delusional disorder. There were 26.6% (n = 77) of subjects who presented with RBD: 28 (36%) with onset before and 49 (63%) with onset after PD diagnosis. The presence of RBD was associated with an increased risk of manifesting hallucinations and delusions (odds ratio [OR], 2.73). Other independent clinical factors found to have an effect on psychotic disorders were cognitive impairment (OR, 3.92), disease duration (OR, 2.46), advanced age (OR, 2.34), and severity of motor symptoms (OR, 2.06). These results suggest that RBD is widely associated with psychosis in PD. © 2005 Movement Disorder Society
Concurrent fMRI and optical measures for the investigation of the hemodynamic response function
Authors: Kennerley Aneurin J. , Berwick Jason , Martindale John , Johnston David , Papadakis Nikos , Mayhew John E.
Published: July 2005

Functional magnetic resonance imaging (fMRI) signal variations are based on a combination of changes in cerebral blood flow (CBF) and volume (CBV), and blood oxygenation. We investigated the relationship between these hemodynamic parameters in the rodent barrel cortex by performing fMRI concurrently with laser Doppler flowmetry (LDF) or optical imaging spectroscopy (OIS), following whisker stimulation and hypercapnic challenge. A difference between the positions of the maximum blood oxygenation level‐dependent (BOLD) and CBV changes was observed in coronal fMRI maps, with the BOLD region being more superficial. A 6.5% baseline blood volume fraction in this superficial region dropped to 4% in deeper cortical layers (corresponding to total hemoglobin baseline volumes Hbt0 = 110 μM and 67 μM, respectively), as inferred from maps of ΔR. Baseline volume profiles were used to parameterize the Monte Carlo simulations (MCS) to interpret the 2D OIS. From this it was found that the optical blood volume measurements (i.e., changes in total hemoglobin) equated with CBV‐MRI measurements when the MRI data were taken from superficial cortical layers. Optical measures of activation showed a good spatial overlap with fMRI measurements taken in the same plane (covering the right hemisphere surface). Changes in CBV and CBF followed the scaling relationship CBV = CBFα, with mean α = 0.38 ± 0.06. Magn Reson Med 54:354–365, 2005. © 2005 Wiley‐Liss, Inc.
Influence of gradient acoustic noise on fMRI response in the human visual cortex
Authors: Zhang Nanyin , Zhu Xiao‐Hong , Chen Wei
Published: July 2005

A paired‐stimuli paradigm combined with fMRI was utilized to study the effect of gradient acoustic noise on fMRI response in the human primary visual cortex (V1) in terms of the auditory‐visual cross‐modal neural interaction. The gradient noise generated during the fMRI acquisition was used as the primary stimulus, and a single flashing light was used as the secondary stimulus. An interstimulus interval (ISI) separated the two. Six tasks were designed with different ISIs ranging from 50 to 700 ms. Both BOLD signal intensity and the number of activated pixels in V1 were analyzed and examined, and they showed a significant reduction when the gradient noise preceded the flashing light by ∼300 ms. These results indicate that the gradient acoustic noise generated during fMRI acquisitions does interfere with neural behavior and the BOLD signal in the human visual cortex. This interference is modulated by the delay between the gradient noise and visual stimulation, and it can be studied quantitatively when the stimulation paradigm is designed appropriately. This study provides evidence of the auditory–visual interaction during fMRI studies, and the results should have an impact on fMRI applications. Magn Reson Med 54:258–263, 2005. © 2005 Wiley‐Liss, Inc.
How does DWI correlate with white matter structures?
Authors: Ronen Itamar , Ugurbil Kamil , Kim Dae‐Shik
Published: July 2005

Diffusion‐weighted MRI (DWI) is widely used to characterize brain white matter (WM), particularly through the use of diffusion tensor imaging (DTI). In this study the spatial characteristics of DWI in WM of cat visual cortex were investigated at 9.4T at very high resolution. It is shown that the spatial extent of the WM tract as measured from the DWI images depends highly on theb‐value. In particular, when the diffusion gradient is applied perpendicular to the main direction of the fiber tract, the estimated thickness of the tract at the commonly usedb‐value of 1000 s/mm2exceeds by 50% the thickness as it appears on aT2‐weighted image. Only atb‐values greater than 6000 s/mm2does the thickness of the tract approach the thickness characterized by theT2‐weighted image and that observed on histological slices of the same area. Further analysis of these results indicates that the choice ofb‐value of 1000 s/mm2may not be optimal for the demarcation of anisotropic WM structures. DWI at highb‐value may contain spatial information that is more specific to WM tracts. Magn Reson Med 54:317–323, 2005. © 2005 Wiley‐Liss, Inc.
Estimation of renal extraction fraction based on postcontrast venous and arterial differential T1 values: An error analysis
Authors: Levin Yakir S. , Chow Lawrence C. , Pelc Norbert J. , Sommer F. Graham , Spielman Daniel M.
Published: July 2005

An error analysis for quantifying single kidney extraction fraction (EF) via differential T1 measurements in the renal vein (RV) and renal artery (RA) is presented. Sources of error include blood flow effects, the effect of a short repetition time (TR), and the impact of uncertainties in the T1 estimates on the final EF calculations. Blood flow effects were investigated via simulation. For a range of blood velocities in the renal vein that may be found in kidney disease, incomplete refreshment of blood between readouts results in significant errors in T1 estimation. For a .5‐cm slice, 110‐ms sampling interval, and T1 of 600 ms, T1 estimation to within 5% of true T1 requires an average through‐plane velocity of 6.75 cm/s for parabolic flow, and 3.5 cm/s for plug flow. Improvement can be achieved by accurately estimating the fraction of blood that has not refreshed between readouts (fold), while the quality of the T1 estimate varies with the accuracy of fold estimation. Shortening of the TR was investigated using phantom and in vivo studies. T1 was estimated to within 3% of the true value on phantoms, and within 5% of the true value for flowing blood for TR = 2T1. The estimated EF is shown to be very sensitive to the difference between T1RA and T1RV. To achieve 10% or 20% uncertainty in the EF estimate, T1 in the renal vein and renal artery must be estimated to within approximately 1% or 2%. Because of limitations on measurement accuracy and precision, this method appears to be impractical at this time. Magn Reson Med 54:309–316, 2005. © 2005 Wiley‐Liss, Inc.
Quantification of cerebral arterial blood volume and cerebral blood flow using MRI with modulation of tissue and vessel (MOTIVE) signals
Authors: Kim Tae , Kim Seong‐Gi
Published: July 2005

Regional cerebral arterial blood volume (CBVa) and blood flow (CBF) can be quantitatively measured by modulation of tissue and vessel (MOTIVE) signals, enabling separation of tissue signal from blood. Tissue signal is selectively modulated using magnetization transfer (MT) effects. Blood signal is changed either by injection of a contrast agent or by arterial spin labeling (ASL). The measured blood volume represents CBVa because the contribution from venous blood was insignificant in our measurements. Both CBVa and CBF were quantified in isoflurane‐anesthetized rats at 9.4T. CBVa obtained using a contrast agent was 1.1 ± 0.5 and 1.3 ± 0.6 ml/100 g tissue (N = 10) in the cortex and caudate putamen, respectively. The CBVa values determined from ASL data were 1.0 ± 0.3 ml/100 g (N = 10) in both the cortex and the caudate putamen. The match between CBVa values determined by both methods validates the MOTIVE approach. In ASL measurements, the overestimation in calculated CBF values increased with MT saturation levels due to the decreasing contribution from tissue signals, which was confirmed by the elimination of blood with a contrast agent. Using the MOTIVE approach, accurate CBF values can also be obtained. Magn Reson Med 54:333–342, 2005. © 2005 Wiley‐Liss, Inc.
Novel method to estimate and display cerebral cortical degeneration using diffusion‐weighted magnetic resonance imaging
Authors: Yoshiura Takashi , Mihara Futoshi , Tanaka Atsuo , Noguchi Tomoyuki , Togao Osamu , Kuwabara Yasuo , Honda Hiroshi
Published: July 2005

Previous studies have shown that diffusion‐weighted imaging (DWI) is useful for detecting microstructural degradation of neuronal tissue in neurodegenerative diseases. Mapping of cortical degeneration by DWI is potentially useful, but is extremely difficult, mainly because of the partial volume effect resulting from the surrounding cerebrospinal fluid (CSF). In this study a novel method to map and display the cortical damage in neurodegenerative diseases using DWI is proposed. Instead of measuring the cortical diffusivity, the diffusivity of white matter directly beneath the cortex, where neuronal fibers enter or exit the overlying cortex, was measured and mapped onto the cortical surface. The map was viewed in a form of three‐dimensional (3D) rendering. Patients with Alzheimer's disease (AD) showed cortical damage in the temporal and parietal cortices, and a patient with frontotemporal dementia showed damage in the frontal lobe, consistent with the typical topographical distribution of histopathological cortical damage in each of these diseases. The results suggest that subcortical diffusivity closely reflects cortical damage, and that the current mapping technique is a promising tool for evaluating neurodegenerative diseases. Magn Reson Med 54:455–459, 2005. © 2005 Wiley‐Liss, Inc.
Optimizing brain tissue contrast with EPI: A simulated annealing approach
Authors: Ikonomidou Vasiliki N. , van Gelderen Peter , de Zwart Jacco A. , Fukunaga Masaki , Duyn Jeff H.
Published: July 2005

A new magnetization preparation and image acquisition scheme was developed to obtain high‐resolution brain images with optimal tissue contrast. The pulse sequence was derived from an optimization process using simulated annealing, without prior assumptions with regard to the number of radiofrequency (RF) pulses and flip angles. The resulting scheme combined two inversion pulses with the acquisition of three images with varying contrast. The combination of the three images allowed separation of gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) based on T1, contrast. It also enabled the correction of small errors in the initial T1 estimates in postprocessing. The use of three‐dimensional (3D) sensitivity‐encoded (SENSE) echo‐planar imaging (EPI) for image acquisition made it possible to achieve a 1.153 mm3 isotropic resolution within a scan time of 10 min 21 s. The cortical GM signal‐to‐noise ratio (SNR) in the calculated GM‐only image varied between 30 and 100. The novel technique was evaluated in combination with blood oxygen level‐dependent (BOLD) functional magnetic resonance imaging (fMRI) on human subjects, and provided for excellent coregistration of anatomical and functional data. Magn Reson Med 54:373–385, 2005. Published 2005 Wiley‐Liss, Inc.
64‐channel array coil for single echo acquisition magnetic resonance imaging
Authors: McDougall Mary Preston , Wright Steven M.
Published: July 2005

A 64‐channel array coil for magnetic resonance imaging (MRI) has been designed and constructed. The coil was built to enable the testing of a new imaging method, single echo acquisition (SEA) MRI, in which an independent full image is acquired with every echo. This is accomplished by entirely eliminating phase encoding and instead using the spatial information obtained from an array of very narrow, long, parallel coils. The planar pair element design proved to be key in achieving well‐localized field sensitivity patterns and isolated elements, the crucial requirements for performing SEA. The matching and tuning of the array elements were accomplished on the coil array printed circuit board using varactor diodes biased over the RF lines. The array was successfully used to obtain SEA images as well as conventional partially parallel images at unprecedented acceleration factors. Magn Reson Med 54:386–392, 2005. © 2005 Wiley‐Liss, Inc.
Improved quantitative dynamic regional oxygen‐enhanced pulmonary imaging using image registration
Authors: Naish Josephine H. , Parker Geoffrey J. M. , Beatty Paul C. , Jackson Alan , Young Simon S. , Waterton John C. , Taylor Chris J.
Published: July 2005

Oxygen‐enhanced MR imaging has been demonstrated in a number of recent studies as a potential method to visualize regional ventilation in the lung. A quantitative pixel‐by‐pixel analysis is hampered by motion and volume change due to breathing. In this study, image registration via active shape modeling is shown to produce significant improvements in the regional analysis of both static and dynamic oxygen‐enhanced pulmonary MRI for five normal volunteers. The method enables the calculation of regional change in relaxation rate between breathing air and 100% oxygen, which is proportional to the change in regional oxygen concentration, and regional oxygen wash‐in and wash‐out time constants. Registration‐corrected mapping of these parameters is likely to provide improved information in the regional assessment of a range of lung diseases. Magn Reson Med 54:464–469, 2005. © 2005 Wiley‐Liss, Inc.
Limitations of apparent diffusion coefficient‐based models in characterizing non‐gaussian diffusion
Authors: Liu Chunlei , Bammer Roland , Moseley Michael E.
Published: July 2005

Diffusion in complex heterogeneous structures, for example, the neural fiber system, is non‐gaussian. Recently, several methods have been introduced to address the issue of non‐gaussian diffusion in multifiber systems. Some are based on apparent diffusion coefficient (ADC) analysis; and some are based onq‐space analysis. Here, using a simple mathematic derivation, ADC‐based models are shown to be mathematically self‐inconsistent in the presence of non‐gaussian diffusion. Monte Carlo simulation on restricted diffusion is applied to demonstrate the poor data fitting that can result from ADC‐based models. Specific comparisons are performed between two generalized diffusion tensor imaging methods: one of them is based on ADC analysis, and the other is shown to be consistent withq‐space formalism. The issue of imaging asymmetric microstructures is also investigated. Signal phase and spin exchange are necessary to resolve multiple orientations of an asymmetric structure. Magn Reson Med 54:419–428, 2005. © 2005 Wiley‐Liss, Inc.
Common SENSE (sensitivity encoding using hardware common to all MR scanners): A new method for single‐shot segmented echo planar imaging
Authors: Carmichael David W. , Priest Andrew N. , De Vita Enrico , Ordidge Roger J.
Published: July 2005

A new method is presented that enables image acquisition to be segmented into two readouts. This is achieved using a new pulse sequence that creates two components of magnetization with different spatial profiles. Each component of the magnetization is measured in one of the readouts. This produces two images with complimentary “sensitivity profiles” and near identical contrast. The images can be acquired with a reduced data matrix that corresponds to shorter periods of data acquisition. The reduced matrix images are then combined to produce a full matrix image using reconstruction methods previously applied to images from multiple RF coils in the sensitivity encoding (SENSE) technique.

The most promising application for this technique is in improving the performance of echo planar imaging (EPI) at high field. In this application, common SENSE obtains two segments of data in a single excitation of the magnetization (i.e., two readouts are performed per shot). The combination of these segments in image space avoids the difficulties normally associated with segmented EPI methods, namely, increased ghosting from discontinuities in the k‐space data. The main advantages are a reduction in distortion and blurring. Common SENSE is compatible with parallel imaging and partial Fourier methods. Magn Reson Med 54:402–410, 2005. © 2005 Wiley‐Liss, Inc.
Noise removal in magnetic resonance diffusion tensor imaging
Authors: Chen Bin , Hsu Edward W.
Published: July 2005

Although promising for visualizing the structure of ordered tissues, MR diffusion tensor imaging (DTI) has been hampered by long acquisition time and low spatial resolution associated with its inherently low signal‐to‐noise ratio (SNR). Moreover, the uncertainty in the DTI measurements has a direct impact on the accuracy of structural renderings such as fiber streamline tracking. Noise removal techniques can be used to improve the SNR of DTI without requiring additional acquisitions, albeit most low‐pass filtering methods are accompanied by undesirable image blurring. In the present study, a modified vector‐based partial‐differential‐equation (PDE) filtering formalism was implemented for smoothing DTI vector fields. Using an image residual‐energy criterion to equate the degree of smoothing and error metrics empirically derived from DTI data to quantify the relative performances, the effectiveness in denoising DTI data is compared among image‐based and vector‐based PDE and fixed and adaptive low‐passk‐space filtering. The results demonstrate that the edge‐preservation feature of the PDE approach can be highly advantageous in enhancing DTI measurements, particularly for vector‐based PDE filtering in applications relying on DTI directional information. These findings suggest a potential role for the postprocessing enhancement technique to improve the practical utility of DTI. Magn Reson Med 54:393–407, 2005. © 2005 Wiley‐Liss, Inc.
High‐resolution nuclear magnetic resonance spectroscopy of biological tissues using projected magic angle spinning
Authors: Martin Rachel W. , Jachmann Rebecca C. , Sakellariou Dimitris , Nielsen Ulla Gro , Pines Alexander
Published: July 2005

High‐resolution NMR spectra of materials subject to anisotropic broadening are usually obtained by rotating the sample about the magic angle, which is 54.7° to the static magnetic field. In projected magic angle spinning (p‐MAS), the sample is spun about two angles, neither of which is the magic angle. This provides a method of obtaining isotropic spectra while spinning at shallow angles. The p‐MAS experiment may be used in situations where spinning the sample at the magic angle is not possible due to geometric or other constraints, allowing the choice of spinning angle to be determined by factors such as the shape of the sample, rather than by the spin physics. The application of this technique to bovine tissue samples is demonstrated as a proof of principle for future biological or medical applications. Magn Reson Med 54:253–257, 2005. © 2005 Wiley‐Liss, Inc.
Modeling and suppression of respiration‐related physiological noise in echo‐planar functional magnetic resonance imaging using global and one‐dimensional navigator echo correction
Authors: Barry Robert L. , Menon Ravi S.
Published: July 2005

A major source of noise in functional magnetic resonance imaging (fMRI) arises from modulations in the local magnetic field in the head due to motion of the subject's chest through the respiratory cycle, and this physiologic noise can nullify the gains in statistical power expected by the use of higher magnetic fields for fMRI. In particular, fMRI data acquired using echo‐planar imaging (EPI) are very sensitive to these spatially and temporally varying respiration‐induced frequency offsets. In this study, accurate 3D magnetic field maps in the head were measured and used to determine the frequency offsets at the two extremes of the respiratory cycle. From these maps, spatially dependent frequency variations from about −1.0 Hz to +1.5 Hz were measured in the brain through the respiratory cycle. Simulations of a typical axial EPI fMRI experiment acquired in the presence of this measured field variation were performed, demonstrating regional image intensity variations between 1 and 5% in single pixel time series. The inadequacy of either global or 1D navigator echo corrections to measure and suppress respiratory‐induced noise in fMRI time series is demonstrated. The nature of the spatial variations observed suggests that 2D approaches should be considered. Magn Reson Med 54:411–418, 2005. © 2005 Wiley‐Liss, Inc.
Biodegradable polymers based on renewable resources. IX. Synthesis and degradation behavior of polycarbonates based on 1,4:3,6‐dianhydrohexitols and tartaric acid derivatives with pendant functional groups
Authors: Yokoe Makito , Aoi Keigo , Okada Masahiko
Published: July 2005

Novel polycarbonates, with pendant functional groups, based on 1,4:3,6‐dianhydrohexitols and L‐tartaric acid derivatives were synthesized. Solution polycondensations of 1,4:3,6‐dianhydro‐bis‐O‐(p‐nitrophenoxycarbonyl)hexitols and 2,3‐di‐O‐methyl‐L‐threitol or 2,3‐O‐isopropylidene‐L‐threitol afforded polycarbonates having pendant methoxy or isopropylidene groups, respectively, with number average molecular weight (Mn) values up to 3.61 × 104. Subsequent acid‐catalyzed deprotection of isopropylidene groups gave well‐defined polycarbonates having pendant hydroxyl groups regularly distributed along the polymer chain. Differential scanning calorimetry (DSC) demonstrated that all the polycarbonates were amorphous with glass transition temperatures ranging from 57 to 98 °C. Degradability of the polycarbonates was assessed by hydrolysis test in phosphate buffer solution at 37 °C and by biochemical oxygen demand (BOD) measurements in an activated sludge at 25 °C. In both tests, the polycarbonates with pendant hydroxyl groups were degraded much faster than the polycarbonates with pendant methoxy and isopropylidene groups. It is noteworthy that degradation of the polycarbonates with pendant hydroxyl groups was remarkably fast. They were completely degraded within only 150 min in a phosphate buffer solution and their BOD‐biodegradability reached nearly 70% in an activated sludge after 28 days. The degradation behavior of the polycarbonates is discussed in terms of their chemical and physical properties. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3909–3919, 2005
Synthesis, morphology, and viscoelastic properties of cyanate ester/polyhedral oligomeric silsesquioxane nanocomposites
Authors: Liang Kaiwen , Toghiani Hossein , Li Guizhi , Pittman Charles U.
Published: July 2005

Cyanate ester (PT‐15, Lonza Corp) composites containing the inorganic–organic hybrid polyhedral oligomeric silsesquioxane (POSS) octaaminophenyl(T8)POSS [1; (C6H4NH2)8(SiO1.5)8] were synthesized. These PT‐15/POSS‐1 composites (99/1, 97/3, and 95/5 w/w) were characterized by X‐ray diffraction (XRD), transmission election microscopy (TEM), dynamic mechanical thermal analysis, solvent extraction, and Fourier transform infrared. The glass‐transition temperatures (Tg's) of the composite with 1 wt % 1 increased sharply versus the neat PT‐15, but 3 and 5 wt % 1 in these cyanate ester composites depressed Tg. All the PT‐15/POSS composites exhibited higher storage modulus (E′) values (temperature > Tg) than the parent resin, but these values decreased from 1 to 5 wt % POSS. The loss factor peak intensities decreased and their widths broadened upon the incorporation of POSS. XRD, TEM, and IR data were all consistent with the molecular dispersion of 1 due to the chemical bonding of the octaamino POSS‐1 macromer into the continuous cyanate ester network phase. The amino groups of 1 reacted with cyanate ester functions at lower temperatures than those at which cyanate ester curing by cyclotrimerization occurred. In contrast to 1, 3‐cyanopropylheptacyclopentyl(T8)POSS [2; (C5H9)7(SiO1.5)8CH2CH2CH2CN] had low solubility in PT‐15 and did not react with the resin below or at the cure temperature. Thus, phase‐separated aggregates of 2 were found in samples containing 1–10 wt % 2. Nevertheless, the Tg and E′ values (temperature > 285 °C) of these composites increased regularly with an increase in 2. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3887–3898, 2005
Cover Picture: Plasma Process. Polym. 6/2005
Authors: Rebrov Aleksei K. , Sharafudinov Rustam S. , Shishkin Andrey V. , Timoshenko Nikolai I.
Published: July 2005

Cover: The pictures on the cover show PTFE‐like structures produced by a supersonic jet of products of PTFE thermal decomposition down to the monomer state. The structures are obtained at different substrate temperatures: at 50 °C (top) and 300 °C (bottom). Further details can be found in the Full Paper by A. K. Rebrov,* R. S. Sharafudinov, A. V. Shishkin, and N. I. Timoshenko on page 464.
DFT investigation of the mechanism of CH2CO + O(3P) reaction
Authors: Sun Hao , Tang Yi‐Zhen , Wang Zhan‐Liang , Pan Xiu‐Mei , Li Ze‐Sheng , Wang Rong‐Shun
Published: July 2005

A detailed theoretical survey of the potential energy surface (PES) for the CH2CO + O(3P) reaction is carried out at the QCISD(T)/6‐311+G(3df,2p)//B3LYP/6‐311+G(d,p) level. The geometries, vibrational frequencies, and energies of all stationary points involved in the reaction are calculated at the B3LYP/6‐311+G(d,p) level. More accurate energy information is provided by single‐point calculations at the QCISD(T)/6‐311+G(3df,2p) level. Relationships of the reactants, transition states, intermediates, and products are confirmed by the intrinsic reaction coordinate (IRC) calculations. The results suggest that P1(CH2+CO2) is the most important product. This study presents highlights of the mechanism of the title reaction. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Signaling pathways of magnolol‐induced adrenal steroidogensis
Authors: Chen Yung-Chia , Chang Ming-Fong , Chen Ying , Wang Seu-Mei
Published: July 2005

This study focused on identifying the signalling mediating the effect of magnolol on corticosterone production. Magnolol‐induced corticosterone production was completely inhibited by mitogen‐activated protein kinase kinase (MEK)‐inhibitor PD98059, tyrosine kinase (TK)‐inhibitor genistein or Janus tyrosine kinase 2 (JAK2)‐inhibitor AG490, suggesting that extracellular signal‐regulated kinase (ERK) and JAK2 are both involved in this signaling cascade. Further, magnolol induced the transient phosphorylation of MEK, ERK, cAMP response‐element binding protein (CREB) and the expression of 32 and 30 kDa steroidogenic acute regulatory protein (StAR) in a time‐dependent manner. Inhibition of TK or JAK2 activities blocked magnolol‐induced phosphorylation of MEK and ERK, again supporting the upstream role of JAK2. The activation of JAK2 or MEK apparently mediated the magnolol‐induced phosphorylation of CREB and the upregulation of StAR. These findings demonstrate a novel pathway for magnolol to induce the expression of StAR, which regulates the rate‐limiting step in sterodiogenesis.
Superoxide determines nitric oxide uptake rate by vascular smooth muscle cells
Authors: Huang Kuang-Tse , Yin Chi-Chau , Wu Joung-Hwa , Huang Hsing-Hsiung
Published: July 2005

Nitric oxide (NO) is generated in endothelial cells, which diffuses to vascular smooth muscle cells (SMCs), activates soluble guanylyl cyclase, and leads to blood vessel dilation. However, this scenario does not explain how SMCs are capable of competing with erythrocytic hemoglobin for NO in vivo. Here, we have developed a competition experiment to determine the NO uptake rate by SMCs and demonstrated that the SMC‐NO uptake rate is positively dependent on intracellular superoxide levels. In addition, the superoxide‐elicited NO influx is able to enhance cGMP production in SMCs. Our findings imply that vascular SMCs, in vivo, may use superoxide to compete with erythrocytic hemoglobin for NO and obtain the NO bioactivity.
Raver2, a new member of the hnRNP family
Authors: Kleinhenz Berenike , Fabienke Manuela , Swiniarski Sascha , Wittenmayer Nina , Kirsch Joachim , Jockusch Brigitte M. , Arnold Hans Henning , Illenberger Susanne
Published: July 2005

Raver2 was identified as a novel member of the hnRNP family based on sequence homology within three RNA recognition motifs and its general domain organization reminiscent of the previously described raver1 protein. Like raver1, raver2 contains two putative nuclear localization signals and a potential nuclear export sequence, and also displays nucleo‐cytoplasmic shuttling in a heterokaryon assay. In glia cells and neurons, raver2 localizes to the nucleus. Moreover, the protein interacts with polypyrimidine tract binding protein (PTB) suggesting that it may participate in PTB‐mediated nuclear functions. In contrast to ubiquitously expressed raver1, raver2 exerts a distinct spatio‐temporal expression pattern during embryogenesis and is essentially restricted to brain, lung, and kidney in the adult mouse.
Effect of temperature and food availability on reproductive investment of first-time spawning male Atlantic cod, Gadus morhua
Authors: Yoneda Michio , Wright Peter J.
Published: July 2005

This study demonstrates how temperature and food availability affect growth, maturation, and sperm production in first-time spawning male cod in captivity. Cod, prior to the onset of maturation, were held under four different varying temperature and feeding regimes between November 2002 and March 2003. Lower food availability resulted in poor growth and body condition. Decreasing temperature partly led to slower growth in fish that matured during the experiment. Low temperature resulted in lesser proportions of mature fish relative to the higher temperature treatments. Higher temperature and food availability resulted in higher sperm production (testicular weight and gonadosomatic index). Our findings suggest that variation in food availability would mainly affect the growth and condition and the level of gamete production whilst variation in temperature would affect the proportion of males that mature. These results are contrasted with similar data for female cod.
A Primer on Genetic Testing
Authors: Constantin Carolyn M. , Faucett Andrew , Lubin Ira M.
Published: July 2005

Use of genetic tests in the clinical practice setting is a current reality, and an increasing number of patients are asking about and requesting genetic testing. The push to translate genetic research findings and technological innovations into clinical practice will continue as our understanding of the genetic basis of disease increases. Special consideration is required when ordering genetic tests, beyond that of other laboratory tests, and an understanding of the unique aspects involved will help optimize clinical outcomes. The purpose of this primer is to provide a basic understanding of genetic testing, discuss current issues related to the use of tests, and outline practical steps for critically using genetic tests in clinical practice.
Newborn Screening and Genetic Testing
Authors: Kenner Carole , Moran Maribeth
Published: July 2005

New screening techniques and diagnostic tests for genetic diseases available for newborn screening can provide information about many diseases long before they are clinically detected. However, this information creates complex questions and ethical dilemmas regarding which newborns should be tested, when testing should occur, availability and costs of tests, and how families should be counseled. There is no national policy regarding newborn screening, which leads to great variation among states'newborn screening programs. This article reviews newborn genetic testing and provides a blueprint for clinicians to improve practice by incorporating into their care knowledge of new developments in newborn testing and screening.
Genetic Competencies Essential for Health Care Professionals in Primary Care
Authors: Engstrom Janet L. , Sefton Marlene G. S. , Matheson Jolie Kim , Healy Kristine M.
Published: July 2005

The completion of the sequencing of the human genome in 2003 signaled the onset of the genomic era in health care. The knowledge gleaned from the Human Genome Project has led to the understanding that every health problem has a genetic component and that clinicians should include the application of genetic information in all aspects of health care. This article describes the genetic competencies essential for all health care professionals in primary care. Health care professionals should augment their current practice by obtaining a multigenerational genetic family history for each patient, assessing all patients for potentially heritable conditions, providing referrals to genetic health professionals as needed, offering genetic testing when indicated, and considering an individual's genetic makeup in the selection of medications and treatments for that person. Finally, all health care professionals ought to be prepared to address the complex personal, cultural, theological, ethical, legal, and social issues associated with genetic testing and other genetic issues commonly encountered in clinical practice.
Speaking the Language of Genetics: A Primer
Authors: Wolpert Chantelle M. , Singer Margaret L. , Speer Marcy C.
Published: July 2005

Genetic research advances will continue to result in clinical applications for genetics in primary care settings. Fluency with the evolving genetic terminology will enable primary care providers to provide better clinical care to their patients, particularly when helping patients understand genetic concepts. This article will help clinicians use genetic terminology with greater precision.
Cochlear Changes in Patients with Type 1 Diabetes Mellitus
Authors: Fukushima Hisaki , Cureoglu Sebahattin , Schachern Patricia A. , Kusunoki Takeshi , Oktay Mehmet F. , Fukushima Naomi , Paparella Michael M. , Harada Tamotsu
Published: July 2005

OBJECTIVE:

To evaluate the effects of diabetes on cochlear elements in human beings.

STUDY DESIGN AND SETTING:

Twenty‐six temporal bones (mean age, 37.5 years) with type 1 diabetes and 30 age‐matched controls were examined by light microscopy. We compared the findings of cochlear vessels, hair cells, spiral ganglion cells, and cochlear lateral walls.

RESULTS:

In diabetics, the walls of vessels of the basilar membrane (P < 0.001) and vessels of the stria vascularis were (P < 0.01) significantly thicker in all turns and loss of outer hair cells (OHCs) was significantly greater in the lower basal turn (P < 0.01). Atrophy of the stria vascularis in all turns (P < 0.0001) and loss of spiral ligament cells in upper turns (P < 0.01) were significantly higher than controls. No significant difference was obtained in the number of spiral ganglion cells between groups.

CONCLUSION:

This study suggests that type 1 diabetes mellitus can cause cochlear microangiopathy and subsequently degeneration of cochlear lateral walls and OHCs.
The Role of Bacterial Interference in Otitis, Sinusitis and Tonsillitis
Authors: Brook Itzhak
Published: July 2005

Bacterial interactions that include antagonism (interference) and synergism help maintain balance between the members of the normal endogenous flora. Alpha‐streptococci that predominate in the normal respiratory tract flora attracted most attention in studies of bacterial interference. Other organisms that possess interfering characteristics in upper respiratory tract infections (URTIs) are nonhemolytic streptococci, and Prevotella and Peptostreptococcus spp. The production of bacteriocins by some microorganisms is one of the important mechanisms of interference. The role of bacterial interference in the development of URTI and its effect on the eradication of these infections is discussed. These infections include pharyngo‐tonsillitis, otitis media, and sinusitis. Treatment with various antimicrobial agents can affect the balance between members of the oro‐pharyngeal bacterial flora and interfering organisms. Implantation into the indigenous microflora of low virulence bacterial strains that are potentially capable of interfering with colonization and infection with other more virulent organisms has been used in preliminary studies as a means of coping with the failure of antimicrobials in the treatment of several URTI.
Religious education in Romania
Authors: Stan Lavinia , Turcescu Lucian
Published: July 2005

This article provides an overview of the Romanian post-communist legislation on religious education in public schools, examined against the background of the 1991 Constitution and international provisions protecting freedom of conscience, critically assesses the pre-university textbooks used in Orthodox and Roman Catholic religion courses, and discusses the churches attempts to ban evolutionary theory from schools and the efforts of the Orthodox Church to introduce religious symbols in public universities.
Fossils and matgrounds from the Neoproterozoic Longmyndian Supergroup, Shropshire, UK
Authors: MCILROY DUNCAN , CRIMES T. PETER , PAULEY JOHN C.
Published: July 2005

Body and trace fossils of Ediacaran affinity are described from strata of the late Neoproterozoic Longmyndian Supergroup exposed near Church Stretton, Shropshire, UK. The almost spherical soft-bodied Ediacaran fossil Beltanelliformis brunsae Menner occurs rarely in the Burway Formation, but much smaller, simpler, discoidal structures are common in both the Burway and Synalds formations and are referred to Beltanelliformis minutae sp. nov. Similar discoidal structures, but with a distinct central depression, are included in Intrites punctatus Fedonkin and are common at several horizons. Two blocks with numerous examples of Medusinites aff. asteroides (Sprigg) Glaessner & Wade were recovered from the Burway Formation. The purported Ediacaran body fossil ‘Arumberia’ Glaessner & Walter is common at several horizons but its biogenicity is not accepted herein. ‘Arumberia’ is thus treated along with evidence for microbially bound sediment surfaces or matgrounds that have been suggested by several authors to be necessary for some types of Ediacaran preservation. The assemblage of simple trace and body fossils along with matgrounds is typical of latest Neoproterozoic time, though some elements range into the Phanerozoic.