bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantifying subclinical central nervous lesions in primary antiphospholipid syndrome: The role of magnetization transfer imaging
Authors: Oliveira de Andrade Danieli Castro , Borba Eduardo Ferreira , Bonfá Eloísa , Freire de Carvalho Jozélio , José da Rocha Antônio , Carlos Maia Antônio 
Published: January 2008

AbstractPurposeTo define the role of magnetization transfer imaging (MTI) in detecting subclinical central nervous system (CNS) lesions in primary antiphospholipid syndrome (PAPS).Materials and MethodsTen non‐CNS PAPS patients were compared to 10 CNS PAPS patients and 10 age‐ and sex‐matched controls. All PAPS patients met Sapporo criteria. All subjects underwent conventional MRI and complementary MTI analysis to compose histograms. CNS viability was determined according to the magnetization transfer ratio (MTR) by mean pixel intensity (MPI) and the mean peak height (MPH). Volumetric cerebral measurements were assessed by brain parenchyma factor (BPF) and total/cerebral volume.ResultsMTR histograms analysis revealed that MPI was significantly different among groups (P < 0.0001). Non‐CNS PAPS had a higher MPI than CNS PAPS (30.5 ± 1.01 vs. 25.1 ± 3.17 percent unit (pu); P < 0.05) although lower than controls (30.5 ± 1.01 vs. 31.20 ± 0.50 pu; P < 0.05). MPH in non‐CNS PAPS (5.57 ± 0.20% (1/pu)) was similar to controls (5.63 ± 0.20% (1/pu), P > 0.05) and higher than CNS PAPS (4.71 ± 0.30% (1/pu), P < 0.05). A higher peak location (PL) was also observed in the CNS PAPS group in comparison with the other groups (P < 0.0001). In addition, a lower BPF was found in non‐CNS PAPS compared to controls (0.80 ± 0.03 vs. 0.84 ± 0.02 units; P < 0.05) but similar to CNS PAPS (0.80 ± 0.03 vs. 0.79 ± 0.05 units; P > 0.05).ConclusionOur findings suggest that non‐CNS PAPS patients have subclinical cerebral damage. The long‐termclinical relevance of MTI analysis in these patients needs to be defined by prospective studies. J. Magn. Reson. Imaging 2008. © 2008 Wiley‐Liss, Inc.
Extent of the last ice sheet in northern Scotland tested with cosmogenic 10Be exposure ages
Authors: Phillips William M. , Hall Adrian M. , Ballantyne Colin K. , Binnie Steven , Kubik Peter W. , Freeman Stewart 
Published: January 2008

AbstractThe extent of the last British–Irish Ice Sheet (BIIS) in northern Scotland is disputed. A restricted ice sheet model holds that at the global Last Glacial Maximum (LGM; ca. 23–19 ka) the BIIS terminated on land in northern Scotland, leaving Buchan, Caithness and the Orkney Islands ice‐free. An alternative model implies that these three areas were ice‐covered at the LGM, with the BIIS extending offshore onto the adjacent shelves. We test the two models using cosmogenic 10Be surface exposure dating of erratic boulders and glacially eroded bedrock from the three areas. Our results indicate that the last BIIS covered all of northern Scotland during the LGM, but that widespread deglaciation of Caithness and Orkney occurred prior to rapid warming at ca. 14.5 ka. Copyright © 2008 John Wiley & Sons, Ltd.
Applications of femtosecond laser induced self‐organized planar nanocracks inside fused silica glass
Authors: Taylor R. , Hnatovsky C. , Simova E. 
Published: January 2008

AbstractWe review our recent experimental efforts towards developing photonic and biophotonic applications of femtosecond laser induced self‐organized planar nanocracks inside fused silica glass. Our results show that sub‐diffraction limited, periodic, planar cracks can be produced, organized, erased and rewritten and basically controlled inside fused silica glass where they can be diagnosed optically using form birefringence. The high degree of control over these self‐replicated periodic structures allows us to investigate applications in micro‐ and nanofluidics, porous capillaries for biofiltering and rewritable data storage for harsh environments.
Interaction of the photobactericides methylene blue and toluidine blue with a fluorophore in Pseudomonas aeruginosa cells
Authors: Usacheva M.N. , Teichert M.C. , Usachev Y.M. , Sievert C.E. , Biel M.A. 
Published: January 2008

AbstractBackground and ObjectivesThe difference in photobactericidal efficacy between methylene blue (MB) and toluidine blue (TB) may be explained by their involvement with proteins, lipopolysaccharides (LPS), and siderophores and siderophore‐receptor protein complexes on the bacterial outer membrane. This study aims to determine if this is the case by using the fluorescence given off by a pseudomonal siderophore named pyoverdin.Study Design/Materials and MethodsConfocal laser scanning microscopy was used to observe the fluorescence of Pseudomonas aeruginosa cells excited at 488 nm in the presence of increasing dye concentrations.ResultsCellular fluorescence at 522 nm progressively decreased with increasing dye concentrations. The Stern–Volmer constants for cellular fluorescence quenching with the dyes were compared to the association constants for dyes complexed with LPS. The quenching of cellular fluorescence was associated with the formation of a ground‐state complex between the dyes and pyoverdin–FpvA protein system. MB readily complexed with this system, whereas TB complexed more strongly with LPS.ConclusionThe different affinities of the dyes for both pyoverdin–protein and LPS will affect the contributions of the dyes' interactions with these biopolymers to the overall bacterial photodamage. Lesers Surg. Med. 40:55–61, 2008. © 2008 Wiley‐Liss, Inc.
Repair of a large congenital diaphragmatic defect with a reverse latissimus dorsi muscle flap
Authors: Barbosa Rui F. , Rodrigues Jorge , Correia‐Pinto Jorge , Costa‐Ferreira António , Cardoso Augusta , Reis Jorge C. , Amarante José M. 
Published: January 2008

AbstractAdvances in neonatal care have led to an increase in the survival rate of children with large congenital diaphragmatic defects. Reconstruction by direct closure is not usually possible and surgical correction in the newborn consists of synthetic patch closure. Recurrence and complications are high with this technique and a latter reconstruction with living tissue is now advocated. We report a case of congenital diaphragmatic hernia treated initially by synthetic patch closure and 10 months latter, after a recurrence, with a reinnervated reverse latissimus dorsi (RLD) flap. We used an end‐to‐side neural coaptation of the thoracodorsal nerve to the phrenic nerve. The result was satisfactory, with remission of symptoms and improvement in growth and development, with permanent pleuro‐peritoneal separation, normal lung growth, and apparent neodiaphragmatic function. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
Free‐tissue transfers for reconstruction of oromandibular area in children
Authors: Bilkay Ufuk , Tiftikcioglu Yigit Ozer , Temiz Gokhan , Ozek Cuneyt , Akin Yalcin 
Published: January 2008

AbstractIntroduction: Currently, free‐tissue transfers are commonly used for various reconstructive purposes in adults. However, there is a lack of large series of free flap reconstruction in children, especially for reconstruction of oromandibular defects. Our study aims to share our experience in free‐flap reconstruction of some challenging pediatric cases. Materials and methods: Pediatric free‐flap interventions (<18‐year‐old) that were performed between 2000 and 2006 in our clinic were retrospectively evaluated. Eighteen free‐tissue transfers were performed in 17 pediatric cases. Epidemiologic data, etiology, defects, preferred free flaps, and results have been compared and analyzed. Results: A total of 17 patients (18 free flaps) were analyzed. Mean age was 10.4 years. The etiology was tumor in 11 cases, traffic accident in 5 cases, and gunshot in 1 case. Double‐flap transfer was performed to one patient with a devastating shotgun wound and single flap transfers to others. A total of 8 osseous flaps, 7 osteocutaneous flaps, and 3 septocutaneous flaps were transferred. Total superficial flap necrosis was encountered in one flap (5.8%) while partial superficial necrosis was seen on two flaps (11.7%). Sixteen of the 17 cases reconstructed, including the three cases with complications, resulted in good functional and cosmetic outcome. One case was lost in the sixth postoperative month due to septisemia during chemotherapy. All the surviving 16 cases acquired bony fusion, mastication, and speech in addition to good cosmetic results. Conclusion: Pediatric free‐tissue transfers are increasing due to the development of better equipment, finer surgical technique, and a better understanding of the unique characteristics of pediatric cases. In our opinion, high success rates with good cosmetic and functional results can be obtained if the specific requirements of the pediatric procedures are met. © 2008 Wiley‐Liss, Inc. Microsurgery, 2008.
From diffusion‐weighted MRI to anomalous diffusion imaging
Authors: Hall Matt G. , Barrick Thomas R. 
Published: January 2008

AbstractWe present a novel interpretation of non‐monoexponential diffusion‐weighted signal decay with b‐value in terms of the theory of anomalous diffusion. Anomalous diffusion is the theory of diffusing particles in environments that are not locally homogeneous, such as brain tissue. In such environments the model of restricted diffusion commonly employed in the analysis of diffusion MR data is not valid, leading to a nonlinear time dependence for the mean‐squared displacement of spins, and to a prediction of a stretched exponential form for the signal decay. We show that this prediction leads directly to a new parameter, the anomalous exponent, which may be measured from scan data and from this we can estimate a fractal dimension, dw, which categorizes the complexity of the excursions of diffusing spins. We construct images of the anomalous exponent and fractal dimension from in vivo human brain data. Distributions of exponents and dimensions are constructed in grey and white matter and cerebrospinal fluid. We observe that these distributions peak at biologically plausible values consistent with previous studies: grey matter dw = 2.366 ± 0.31, white matter dw = 2.587 ± 0.39, CSF dw = 1.970 (mode). Marked contrast is observed between grey and white matter when compared with lateral ventricle CSF. We then consider the anisotropy of the value of the anomalous exponent and define quantities analogous to the mean diffusivity and fractional anisotropy that are commonly generated from diffusion tensor images. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Rapid in vivo musculoskeletal MR with parallel imaging at 7T
Authors: Banerjee Suchandrima , Krug Roland , Carballido‐Gamio Julio , Kelley Douglas A.C. , Xu Duan , Vigneron Daniel B. , Majumdar Sharmila 
Published: January 2008

AbstractThe purpose of this work was to implement autocalibrating GRAPPA‐based parallel imaging (PI) for in vivo high‐resolution (HR) MRI of cartilage and trabecular bone micro‐architecture at 7T and to evaluate its performance based on comparison of MR‐derived morphology metrics between accelerated and conventional images and comparison of geometry factor measures between 3T and 7T. Using an eight channel coil array for trabecular MRI at the ankle, a higher maximum feasible acceleration (R) = 6 and lower geometry factor values than that at 3T were observed. The advantages of two‐dimensional acceleration were also demonstrated. In knee cartilage and bone acquisitions, feasibility of PI with a dual‐channel quadrature coil was investigated. Robust quantification of bone and cartilage metrics could be derived from accelerated ankle and knee acquisitions. PI can enhance the clinical feasibility of in vivo bone and cartilage HR‐MRI for osteoporosis and osteoarthritis at 7T. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Diffusion tensor imaging and MR spectroscopy in hypertension and presumed cerebral small vessel disease
Authors: Nitkunan Arani , Charlton Rebecca A. , McIntyre Dominick J.O. , Barrick Thomas R. , Howe Franklyn A. , Markus Hugh S. 
Published: January 2008

AbstractIn patients with cerebral small vessel disease (SVD) diffusion tensor imaging (DTI) is sensitive to white matter damage and correlates better with cognitive function than conventional imaging. It has been proposed as a surrogate marker for treatment trials. However, the pathological changes underlying DTI are not known. The purpose of this study was to use magnetic resonance spectroscopy (MRS) to determine the pathological changes underlying DTI abnormalities in a range of patients from asymptomatic white matter hyperintensities to symptomatic cerebral SVD. 29 SVD patients, 63 hypertensive subjects, and 42 normotensive controls were recruited. The relationship between the DTI and MRS parameters in the centrum semiovale white matter was determined. There was a significant reduction in N‐acetylaspartate (NAA; 2.067 ± 0.042 vs 2.299 ± 0.029 and 2.315 ± 0.036, P = 9 × 10−6) and increase in mean diffusivity (mm2/s × 10−3; 0.942 ± 0.123 vs 0.822 ± 0.064 and 0.792 ± 0.057, P = 1 × 10−8) in symptomatic SVD patients compared with the other two groups. DTI parameters correlated with NAA in all three groups, in a graded manner depending on severity of disease (r −SVD −0.827, hypertensive subjects −0.457, controls −0.317). NAA is a marker of axonal loss/dysfunction. These findings are consistent with axonal loss/dysfunction being the principal process causing the DTI changes found in cerebral SVD and ageing. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Gaussian process modeling for image distortion correction in echo planar imaging
Authors: Stevick Joseph W. , Harding Sally G. , Paquet Ulrich , Ansorge Richard E. , Carpenter T. Adrian , Williams Guy B. 
Published: January 2008

AbstractAn enhanced method for correction of image distortion due to B0‐field inhomogeneities in echo planar imaging (EPI) is presented. The algorithm is based on the measurement of the point spread function (PSF) associated with each image voxel using a reference scan. The expected distortion map in the phase encode direction is then estimated using a nonparametric inference algorithm known as Gaussian process modeling. The algorithm is shown to be robust to the presence of regions of low signal‐to‐noise in the image and large inhomogeneities. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Dynamic monitoring of localized tumor oxygenation changes using RF pulsed electron paramagnetic resonance in conscious mice
Authors: Matsumoto Shingo , Espey Michael Graham , Utsumi Hideo , Devasahayam Nallathamby , Matsumoto Ken‐Ichiro , Matsumoto Atsuko , Hirata Hiroshi , Wink David A. , Kuppusamy Periannan , Subramanian Sankaran , Mitchell James B. , Krishna Murali C. 
Published: January 2008

AbstractOxygenation status is a key determinant in both tumor growth and responses to therapeutic interventions. The oxygen partial pressure (pO2) was assessed using a novel pulsed electron paramagnetic resonance (EPR) spectroscopy at 750 MHz. Crystals of lithium phthalocyanine (LiPc) implanted into either squamous cell carcinoma (SCC) tumor or femoral muscle on opposing legs of mice were tested by pulsed EPR. The results showed pO2 of SCC tumor was 2.7 ± 0.4 mmHg, while in the femoral muscle it was 6.1 ± 0.9 mmHg. A major advantage of pulsed EPR oximetry over conventional continuous‐wave (CW) EPR oximetry is the lack of influence from subject motion, while avoiding artifacts associated with modulation or power saturation. Resonators in pulsed EPR are overcoupled to minimize recovery time. This makes changes in coupling associated with object motion minimal without influencing spectral quality. Consequently, pulsed EPR oximetry enables approximately a temporal resolution of ∼ one second in pO2 monitoring in conscious subjects, avoiding significant influence of anesthetics on the physiology being studied. The pO2 in SCC tumor and muscle was found to be higher without anesthesia (3.9 ± 0.5 mmHg for tumor, 8.8 ± 1.2 mmHg for muscle). These results support the advantage of pulsed EPR in examining pO2 in conscious animals with LiPc chronically implanted in predetermined regions. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
13C saturation transfer effect of carbon dioxide–bicarbonate exchange catalyzed by carbonic anhydrase in vivo
Authors: Yang Jehoon , Singh Sujata , Shen Jun 
Published: January 2008

AbstractCarbonic anhydrase catalyzes reversible hydration of carbon dioxide and dehydration of bicarbonate. In this article we report that the rapid exchange catalyzed by carbonic anhydrase causes a large magnetization (saturation) transfer effect on the 13C signal of bicarbonate at 160.7 ppm in vivo when the resonance of the undetectable carbon dioxide at 125.0 ppm is irradiated with RF pulses. In isoflurane‐anesthetized adult rat brain the unidirectional, pseudo first‐order rate constant of this exchange in the dehydration direction was determined to be 0.47 ± 0.05 sec−1 following intravenous infusion of uniformly 13C‐labeled glucose for labeling bicarbonate. Intralateral ventricular administration of the highly specific carbonic anhydrase inhibitor acetazolamide, which is a drug used for treating glaucoma and epilepsy, was also shown to significantly attenuate the observed 13C magnetization transfer effect of the carbon dioxide–bicarbonate exchange in the rat brain. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.
Quadratic Störmer‐type methods for the solution of the Boussinesq equation by the method of lines
Authors: Tsitouras Ch. , Famelis I. Th. 
Published: January 2008

AbstractWe study the numerical treatment of Boussinesq PDE equation using the method of lines. For the space discretization, we choose either classical finite differences or Fourier pseudospectral methods. Both cases result in a system of second‐order ordinary differential equations (ODEs) that is quadratic. In order to take advantage of this special feature, we choose to solve the ODE system using a new type of hybrid Numerov method specially constructed for such problems. Other efficient ODE solvers taken from the literature are used to solve the system of ODEs as well. By taking all the combinations of space discretization methods and ODE solvers, we discuss the stability and accuracy features revealed from the numerical tests. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008
A multidomain integrated‐radial‐basis‐function collocation method for elliptic problems
Authors: Mai‐Duy N. , Tran‐Cong T. 
Published: January 2008

AbstractThis article is concerned with the use of integrated radial‐basis‐function networks (IRBFNs) and nonoverlapping domain decompositions (DDs) for numerically solving one‐ and two‐dimensional elliptic problems. A substructuring technique is adopted, where subproblems are discretized by means of one‐dimensional IRBFNs. A distinguishing feature of the present DD technique is that the continuity of the RBF solution across the interfaces is enforced with one order higher than with conventional DD techniques. Several test problems governed by second‐ and fourth‐order differential equations are considered to investigate the accuracy of the proposed technique. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008
Numerical solutions of the space‐time fractional advection‐dispersion equation
Authors: Momani Shaher , Odibat Zaid 
Published: January 2008

AbstractFractional advection‐dispersion equations are used in groundwater hydrologhy to model the transport of passive tracers carried by fluid flow in a porous medium. In this paper we present two reliable algorithms, the Adomian decomposition method and variational iteration method, to construct numerical solutions of the space‐time fractional advection‐dispersion equation in the form of a rabidly convergent series with easily computable components. The fractional derivatives are described in the Caputo sense. Some examples are given. Numerical results show that the two approaches are easy to implement and accurate when applied to space‐time fractional advection‐dispersion equations. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2008
Effect of fiber length and composition on mechanical properties of carbon fiber‐reinforced polybenzoxazine
Authors: Kumar K. S. Santhosh , Nair C. P. Reghunadhan , Ninan K. N. 
Published: January 2008

AbstractThe mechanical strength and modulus of chopped carbon fiber (CF)‐reinforced polybenzoxazine composites were investigated by changing the length of CFs. Tensile, compressive, and flexural properties were investigated. The void content was found to be higher for the short fiber composites. With increase in fiber length, tensile strength increased and optimized at around 17 mm fiber length whereas compressive strength exhibited a continuous diminution. The flexural strength too increased with fiber length and optimized at around 17 mm fiber length. The increase in strength of composites with fiber length is attributed to the enhancement in effective contact area of fibers with the matrix. The experimental results showed that there was about 350% increase in flexural strength and 470% increase in tensile strength of the composites with respect to the neat polybenzoxazine, while, compressive properties were adversely affected. The composites exhibited an optimum increase of about 800% in flexural modulus and 200% in tensile modulus. Enhancing the fiber length, leads to fiber entanglement in the composites, resulted in increased plastic deformation at higher strain. Multiple branch matrix shear, debonded fibers and voids were the failures visualized in the microscopic analyses. Defibrillation has been exhibited by all composites irrespective of fiber length. Fiber debonding and breaking were associated with short fibers whereas clustering and defibrillation were the major failure modes in long fiber composites. Increasing fiber loading improved the tensile and flexural properties until 50–60 wt% of fiber whereas the compressive property consistently decreased on fiber loading. Copyright © 2008 John Wiley & Sons, Ltd.
Cohesin‐dockerin microarray: Diverse specificities between two complementary families of interacting protein modules
Authors: Haimovitz Rachel , Barak Yoav , Morag Ely , Voronov‐Goldman Milana , Shoham Yuval , Lamed Raphael , Bayer Edward A. 
Published: January 2008

AbstractThe cellulosome is an intricate multienzyme complex, designed for efficient degradation of plant cell wall polysaccharides, notably cellulose. The supramolecular cellulosome architecture in different bacteria is the consequence of the types and specificities of the interacting cohesin and dockerin modules, borne by the different cellulosomal subunits. In this study, we describe a microarray system for determining cohesin‐dockerin specificity, which allows global comparison among the interactions between various members of these two complementary families of interacting protein modules. Matching recombinant fusion proteins were prepared that contained one of the interacting modules: cohesins were joined to an appropriate cellulose‐binding module (CBM) and the dockerins were fused to a thermostable xylanase that served to enhance expression and proper folding. The CBM‐fused cohesins were immobilized on cellulose‐coated glass slides, to which xylanase‐fused dockerin samples were applied. Knowledge of the specificity characteristics of native and mutated members of the cohesin and dockerin families provides insight into the architecture of the parent cellulosome and allows selection of suitable cohesin‐dockein pairs for biotechnological and nanotechnological application. Using this approach, extensive cross‐species interaction among type‐II cohesins and dockerins is shown for the first time. Selective intraspecies binding of an archaeal dockerin to two complementary cohesins is also demonstrated.