bluuebunny/crossref_metadata_2025 huggingface dataset:
Damage and molecular changes under a laser beam in SEM‐EDX/MRS interface: a case study on iron‐rich particles
Authors: Worobiec A. , Darchuk L. , Brooker A. , Potgieter H. , Van Grieken R.
Published: September 2010

The control of damage to individual environmental particles by a laser beam during Raman spectroscopy carried out in ambient air is generally well understood. The nature and control of damage under vacuum conditions (e.g. in the scanning electron microscopy with energy X‐ray detection combined with micro‐Raman spectroscopy—interfaced SEM‐EDX/MRS) are more complex and less well comprehended. The physical and chemical processes that affect the damage caused to small particles by lasers still remain somewhat unclear, but certainly the atmosphere (vacuum/air) and the beam intensity have very significant influences. Furthermore, it has been determined that some particles (e.g. haematite), although stable under an electron beam, are damaged by the laser beam, hampering their analysis. Additionally, when simultaneous analyses by SEM/EDX and MRS are considered, the correct choice of the collection surface plays a crucial role. As a result, the following collection substrates were tested to determine their influence on the laser beam damage process to the particle: silver and aluminium foils and silicon wafers. A test study was performed using artificial examples of haematite (Fe2O3) particles. Exposure of Fe2O3 particles in vacuum to 514‐ and 785‐nm laser radiation often leads to their melting, transformation and evaporation. The dependence of the damage caused by the laser beam on the particle structure is reported here. Molecular and crystallographic changes have also been revealed. Formation of magnetite (as an effect of re‐crystallisation) and Raman inactive structures was detected. Copyright © 2010 John Wiley & Sons, Ltd.
A comprehensive spectroscopic study of synthetic Fe2+, Fe3+, Mg2+ and Al3+ copiapite by Raman, XRD, LIBS, MIR and vis–NIR
Authors: Kong W. G. , Wang Alian , Freeman John J. , Sobron Pablo
Published: September 2010

The identification of iron sulfates on Mars by the Mars Exploration Rovers (MERs) and the Mars Reconnaissance Orbiter emphasized the importance of studying iron sulfates in laboratory simulation experiments. The copiapite group of minerals was suggested as one of the potential iron sulfates occurring on the surface and subsurface on Mars, so it is meaningful to study their spectroscopic features, especially the spectral changes caused by cation substitutions. Four copiapite samples with cation substitutions (Fe3+, Al3+, Fe2+, Mg2+) were synthesized in our laboratory. Their identities were confirmed by powder X‐ray diffraction (XRD). Spectroscopic characterizations by Raman, mid‐IR, vis‐NIR and laser‐induced‐breakdown spectroscopy (LIBS) were conducted on those synthetic copiapite samples, as these technologies are being (and will be) used in current (and future) missions to Mars. We have found a systematic ν1peak shift in the Raman spectra of the copiapite samples with cation substitutions, a consistent atomic ratio detection by LIBS, a set of systematic XRD line shifts representing structural change caused by the cation substitutions and a weakening of selection rules in mid‐IR spectra caused by the low site symmetry of (SO4)2− in the copiapite structures. The near‐infrared (NIR) spectra of the trivalent copiapite species show two strong diagnostic water features near 1.4 and 1.9 µm, with two additional bands near 2.0 µm. In the vis‐NIR spectra, the position of an electronic band shifts from 0.85 µm for ferricopiapite to 0.866 µm for copiapite, and this shift suggests the appearance of a Fe2+ electronic transition band near 0.9 µm. Copyright © 2010 John Wiley & Sons, Ltd.
Raman study of NiFe2O4 nanoparticles, bulk and films: effect of laser power
Authors: Ahlawat Anju , Sathe V. G.
Published: September 2010

Nanoparticles, bulk and thin films of NiFe2 O4 compounds are studied by micro‐Raman spectroscopy. The effect of varying the incident laser power up to 40 mW was studied in all forms of the samples. The spectra showed a large magnitude of red shift and line broadening as a result of high incident laser power. It is shown that the inverse spinel structure remains robust, and no trace of laser‐induced oxidation was observed. The low‐temperature study of the bulk and nanoparticles has also been carried out for elucidating thermal effects due to the high incident laser power. The rise in temperature for maximum incident laser power of 40 mW was estimated to be ∼625 °C. Copyright © 2010 John Wiley & Sons, Ltd.
Protein dynamics of heme–heme oxygenase‐1 complex following carbon monoxide dissociation
Authors: Yamaoka Masato , Sugishima Masakazu , Noguchi Masato , Fukuyama Keiichi , Mizutani Yasuhisa
Published: September 2010

Structural changes of heme‐heme oxygenase‐1 complex following carbon monoxide (CO) dissociation were studied by time‐resolved resonance Raman spectroscopy. We observed temporal changes for resonance Raman bands of the Fe–His stretch and the heme propionate bends in the subnanosecond and microsecond time regimes. These changes suggest structural rearrangements in the Fe–His linkage and the salt bridges of the heme propionates following CO dissociation. The present data supports the model proposed by an X‐ray crystallographic study. The Fe–His stretching mode exhibited an upshift until 30 µs after dissociation as the delay time increased. This is the first example of a CO‐dissociation‐induced strengthening of the Fe‐His linkage in hemeproteins. Copyright © 2010 John Wiley & Sons, Ltd.
Assessment of robustness and transferability of classification models built for cancer diagnostics using Raman spectroscopy
Authors: Sattlecker Martina , Stone Nick , Smith Jennifer , Bessant Conrad
Published: September 2010

Over recent years, Raman spectroscopy has been demonstrated as a prospective tool for application in cancer diagnostics. The use of Raman spectroscopy for this purpose relies on pattern recognition methods that have been developed to perform well on data achieved under laboratory conditions. However, the application of Raman spectroscopy as a routine clinical tool is likely to result in imperfect data due to instrument‐to‐instrument variation. Such corruption to the pure tissue spectral data is expected to negatively impact the classification performance of the diagnostic model. In this paper, we present a thorough assessment of the robustness of the Raman approach. This was achieved by perturbing a set of spectra in different ways, including various linear shifts, nonlinear shifts and random noise and using previously optimised classification models to predict the class membership of each spectrum in a testing set. The loss of predictive power with increased corruption was used to calculate a score, which allows an easy comparison of the model robustness. For this approach, three different types of classification models, including linear discriminant analysis (LDA), partial least square discriminant analysis (PLS‐DA) and support vector machine (SVM), built for lymph node diagnostics were the subject of the robustness testing. The results showed that a linear perturbation had the highest impact on the performance of all classification models. Among all linear corruption methods, a gradienty‐shift resulted in the highest performance loss. Thus, the factor most likely to affect the predictive outcome of models when using different systems is a gradienty‐shift. Copyright © 2010 John Wiley & Sons, Ltd.
Silver‐coated inverse opals formed from polystyrene spheres for surface‐enhanced Raman scattering
Authors: Mu Weiqiang , Hwang Dae‐Kue , Chang Robert P. H. , Ketterson John B.
Published: September 2010

We have developed a new substrate for surface‐enhanced Raman scattering (SERS) measurements involving a thin silver layer deposited over an ion‐etched TiO2 inverse opal. The latter is formed by chemically infiltrating a polystyrene opal array with TiO2 followed by a thermal decomposition of the spheres. The SERS response of the these substrates is examined for several sphere sizes and lasers wavelengths; the results show that such substrates yield high enhance factors, comparable to substrates involving a silver layer deposited directly on a polystyrene opal array. Copyright © 2010 John Wiley & Sons, Ltd.
Multiphonon probe in ZnS quantum dots
Authors: Dhara S. , Arora A. K. , Bera Santanu , Ghatak Jay
Published: September 2010

Raman spectroscopic studies have been performed for ZnS nanoclusters in this study. Cluster size dependent multiphonon properties are reported in detail. A flurry of zone boundary phonons is demonstrated in the scattering process. A strong deformation potential (DP) dominated Raman spectra are reported for cubic ZnS nanocluster of diameter with ∼2.2 nm in size below the quantum confinement. Transverse optic (TO) mode in the multiphonon process shows only even order overtones for 2.2 nm cluster, suggesting the dominance of a two‐phonon process and its integral multiples. The possibility of surface oxidation in the smallest cluster is ruled out as a plausible explanation for the observed even order TO modes which resemble the higher order modes of ZnO. A wave vector‐independence of electron–phonon interaction in quantum dots leads to strong dependence on DP‐related phenomenon. A large DP value for the second‐order process in ZnS than that with respect to the first‐order process is made responsible for the observed phenomenon. Copyright © 2010 John Wiley & Sons, Ltd.
Evidences of the evolution from solid solution to surface segregation in Ni‐doped SnO2 nanoparticles using Raman spectroscopy
Authors: Aragón F. H. , Coaquira J. A. H. , Hidalgo P. , da Silva S. W. , Brito S. L. M. , Gouvêa D. , Morais P. C.
Published: September 2010

Ni‐doped SnO2 nanoparticles, promising for gas‐sensing applications, have been synthesized by a polymer precursor method. X‐ray diffraction (XRD) and transmission electron microscopy (TEM) data analyses indicate the exclusive formation of nanosized particles with rutile‐type phase (tetragonal SnO2) for Ni contents below 10 mol%. The mean crystallite size shows a progressive reduction with the Ni content. Room‐temperature Raman spectra of Ni‐doped SnO2 nanoparticles show the presence of Raman active modes and modes activated by size effects. From the evolution of the A1g mode with the Ni content, a solubility limit at ∼2 mol% was estimated. Below that content, Raman results are consistent with the occurrence of solid solution (ss) and surface segregation (seg.) of Ni ions. Above ∼2 mol% Ni, the redshift of A1g mode suggests that the surface segregation of Ni ions takes place. Disorder‐activated bands were determined and their integrated intensity evolution with the Ni content suggest that the solid‐solution regime favors the increase of disorder; meanwhile, that disorder becomes weaker as the Ni content is increased. Copyright © 2010 John Wiley & Sons, Ltd.
Single‐crystal Raman spectroscopy of brandholzite Mg[Sb(OH)6]2•6H2O and bottinoite Ni[Sb(OH)6]2• 6H2O and the polycrystalline Raman spectrum of mopungite Na[Sb(OH)6]
Authors: Rintoul Llew , Bahfenne Silmarilly , Frost Ray L.
Published: September 2010

The single‐crystal Raman spectra of minerals brandholzite and bottinoite, formula M[Sb(OH)6]2•6H2O, where M is Mg+2 and Ni+2, respectively, and the non‐aligned Raman spectrum of mopungite, formula Na[Sb(OH)6], are presented for the first time. The mixed metal minerals comprise alternating layers of [Sb(OH)6]−1 octahedra and mixed [M(H2O)6]+2/[Sb(OH)6]−1 octahedra. Mopungite comprises hydrogen‐bonded layers of [Sb(OH)6]−1 octahedra linked within the layer by Na+ ions. The spectra of the three minerals were dominated by the SbO symmetric stretch of the [Sb(OH)6]−1 octahedron, which occurs at approximately 620 cm−1. The Raman spectrum of mopungite showed many similarities to spectra of the di‐octahedral minerals, supporting the view that the Sb octahedra give rise to most of the Raman bands observed, particularly below 1200 cm−1. Assignments have been proposed on the basis of the spectral comparison between the minerals, prior literature and density functional theory (DFT) calculations of the vibrational spectra of the free [Sb(OH)6]−1 and [M(H2O)6]+2 octahedra by a model chemistry of B3LYP/6‐31G(d) and lanl2dz for the Sb atom. The single‐crystal spectra showed good mode separation, allowing most of the bands to be assigned to the symmetry species A or E. Copyright © 2010 John Wiley & Sons, Ltd.
Why the ΔνCH blue shift is larger in chloral than in dichloroacetyl chloride dimers?
Authors: Szostak Roman
Published: September 2010

Raman spectra of the Cl3CCHO/CCl4 and Cl3CCHO/C6D12 binary systems were recorded as a function of the mole fraction. Features originating from self‐aggregates of chloral (trichloroethanal, trichloroacetaldehyde—TCAA) molecules were detected in different spectral regions. The most pronounced changes were observed in the vicinity of the ν(CO) and ν(CH) stretching vibration bands. Using two‐dimensional correlation spectroscopy (2D‐COS), evolving‐factor analysis (EFA) and multivariate curve resolution (MCR), dimer bands were identified, and their positions were determined. The ν(CH) stretching vibration band in dimers was blue‐shifted by nearly 18 cm−1, whereas the ν(CO) dimer band was red‐shifted by more than 5 cm−1. For these bands, the observed shifts were accompanied by an almost twofold change in the bandwidth, from approximately 19 and 6 cm−1 for dilute solutions (x = 0.05) to 36.6 and 11.5 cm−1, respectively, in pure TCAA. The formation of dimers was confirmed by multivariate analysis of the Raman spectra of chloral recorded as a function of temperature. Analogous analysis of dichloroacetyl chloride (DCAC) spectra gave an 8.9 cm−1 blue shift for the ν(CH) vibration band and − 5.5/− 10.1 cm−1 shifts for the ν(CO) stretching vibrations of the two conformers present. To facilitate the interpretation of experimental findings, the optimized geometries and vibrational wavenumbers of the Cl3CCHO/HCl2CCClO molecules and (Cl3CCHO)2/(HCl2CCClO)2 dimers were calculated at the B3LYP/6‐311 + + G(3df,3pd) level. Copyright © 2010 John Wiley & Sons, Ltd.
Roles of paeoniflorin and senkyunolide I in SiWu decoction on antiplatelet and anticoagulation activities
Authors: Zhu Min , Tang Yuping , Duan Jin‐ao , Guo Jianming , Guo Sheng , Su Shulan , Shang Erxin , Qian Dawei , Ding Anwei
Published: September 2010

Traditional Chinese medicine (TCM) is a complex system, which consists of numerous compounds with related mechanisms to maximize therapeutic efficacy with minimal adverse effects. Some new methods disclosing the contribution of these constituents as well as their relationship in the formula are necessary for elucidating the bio‐active constituents and the working mechanisms of TCM. In this study, depletion of target components using preparative HPLC followed by antiplatelet and anticoagulation activities evaluation was first applied to investigate the roles of paeoniflorin and senkyunolide I in a well‐known formula, SiWu decoction. The results showed that both paeoniflorin and senkyunolide I not only directly brought about some bio‐activities, but also indirectly made the contribution to the total bio‐activity reflection of SiWu decoction, especially the latter should deserve to be drawn attention to the research of complicated bio‐active constituents of TCM or its formula. So, the significant and effective approach will be very useful for the elucidation of the contribution of each different chemical constituent to the bio‐activity of a TCM formula. Furthermore, this study demonstrated the potential utilization of preparative HPLC in the research of TCM.
Determination of hexabromocyclododecane diastereoisomers in Sargassum fusiforme and comparison of the extraction efficiency of ultrasonication, microwave‐assisted extraction, Soxhlet extraction and pressurised liquid extraction
Authors: Han Chao , Chen Xiaomei , Xie Wen , Zhu Zhenou , Liu Cuiping , Chen Fan , Shen Yan
Published: September 2010

The concentrations of hexabromocyclododecanes (HBCD) in Sargassum fusiforme, the common Chinese edible seaweed, were investigated by LC‐MS/MS. For the recovery of HBCD, the efficiency levels of ultrasonic‐assisted extraction, microwave‐assisted extraction, Soxhlet extraction and pressurised liquid extraction were compared under different conditions. Pressurised liquid extraction and ultrasonic‐assisted extraction resulted in complete extraction of HBCD (92.7–102.5% recovery). Microwave‐assisted extraction and Soxhlet extraction, on the other hand, offered relatively low extraction recoveries (82.1–90.6%). The instrumental LODs on columns in this study were 1.0, 0.3 and 0.7 ng/g for α‐HBCD, β‐HBCD and γ‐HBCD, respectively. Because of its accuracy, this straightforward method is particularly suitable for routine HBCD analysis.
Effects of soil conservation on soil properties of citrus orchards in the Three‐Gorges Area, China
Authors: XU Q. X. , Wang T. W. , CAI C. F. , Li Z. X. , SHI Z. H.
Published: September 2010

Mountain region citrus production systems occupy large parts of the landscape prone to soil erosion in the Three‐Gorges Area of China. Several soil conservation measures, such as terracing hedgerows, are widely implemented in citrus orchards to control soil erosion. However, little is known about the effect of those measures on soil properties. The objective of this work was to analyse the changes of soil properties in citrus orchards subjected to different conservation measures. Experiments were conducted in four plots: control plot (SC, sloping orchard without conservation measures), sloping orchard with contour hedgerows (SCH), terraced orchard (TC) and terraced orchard with grass cover (TCG). Samples of soil surface from 0 to 15 cm were collected to analyse texture, bulk density (BD), aggregate stability, saturated hydraulic conductivity, soil organic matter (SOM) and soil nutrients. The spatial variability of those properties was also evaluated at slope and field scales. The results showed that the three conservation measures significantly increased saturated hydraulic conductivity, aggregate stability, SOM and available N, P, K, but decreased BD. The terracing with grass cover measures were the most effective in improving soil fertility among the three measures. The average SOM, available P, N, K in TCG were 0·27, 0·50, 1·74 and 1·72 and these rates are larger than for the in SC. Compared to SC, silt content was increased the SCH, while clay content was increased with TC and TCG. There was a downslope increase in clay content and total N but a decrease in gravels in the SC plot. However, that trend did not exist in the other plots. At the field scale, the soil aggregate stability and total nitrogen were significantly higher near the hedgerow under SCH, and the available N was significantly higher in the middle position under TC; the other soil properties had no significant trends based on the distance to hedgerow or stone bunds. Results of this study will contribute to a further understanding of the environmental influence of soil conservation measures. Copyright © 2010 John Wiley & Sons, Ltd.
Fibrin sealant decreases postoperative drainage in immediate breast reconstruction by deep inferior epigastric perforator flap after mastectomy with axillary dissection
Authors: Hivelin Mikaël , Heusse Jean Laurent , Matar Nadia , Lepage Christophe , Lantieri Laurent
Published: September 2010

Background:

Serosanguinous drainage after breast reconstruction by deep inferior epigastric perforator flap (DIEP) can limit patient's discharge. We introduced fibrin sealant in immediate breast reconstruction by DIEP flap to reduce drainage after mastectomy with axillary dissection.

Materials and methods:

We performed an open study on 30 consecutive female aged from 28 to 63 years old. All underwent immediate breast reconstructions by DIEP flaps after mastectomy and axillary dissection for cancer. Patients were divided in group 1 (N = 15) without fibrin sealant and group 2 (N = 15) where the flap, thoracic, and axillary areas were sprayed with 5 mL of liquid fibrin sealant before drains insertion. There was no difference in the patient's BMI, height, weight or age between both the groups. Blake suction drains were placed under the flap and in the axillary area.

Results:

No adverse effects were reported, after a 20‐month median follow‐up. Drainage volumes or durations were not correlated to the patient's BMI, nor the height, weight or age. Thoracic drainage duration was longer than abdominal drainage in both the groups. Average drained volumes from the thoracic area were lower (427 vs. 552 mL; P = 0.015) and thoracic drains were removed earlier (5.47 vs. 6.33 days P = 0.022), in group 2 than in group 1. The length of stay was also reduced after the use of fibrin sealant (5.53 vs. 6.33 days; P = 0.032).

Conclusion:

This study introduce the interest of fibrin sealant to significantly decrease the postoperative drainage volume and duration in the thoracic area after immediate breast reconstruction by DIEP flap. © 2010 Wiley‐Liss, Inc. Microsurgery, 2011.
Efficient implementation of hardware‐optimized gradient sequences for real‐time imaging
Authors: Derbyshire J. Andrew , Herzka Daniel A. , McVeigh Elliot R. , Lederman Robert J.
Published: September 2010

This work improves the performance of interactive real‐time imaging with balanced steady‐state free precession. The method employs hardware‐optimized gradient pulses, together with a novel phase‐encoding strategy that simplifies the design and implementation of the optimized gradient waveforms. In particular, the waveforms for intermediate phase‐encode steps are obtained by simple linear combination, rather than separate optimized waveform calculations. Gradient waveforms are redesigned in real time as the scan plane is manipulated, and the resulting sequence operates at the specified limits of the MRI gradient subsystem for each new scan‐plane orientation. The implementation provides 14‐25% improvement in the sequence pulse repetition time over the vendor‐supplied interactive real‐time imaging sequence for similar scan parameters on our MRI scanner. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Effect of improving spatial or temporal resolution on image quality and quantitative perfusion assessment with k‐t SENSE acceleration in first‐pass CMR myocardial perfusion imaging
Authors: Maredia Neil , Radjenovic Aleksandra , Kozerke Sebastian , Larghat Abdulghani , Greenwood John P. , Plein Sven
Published: September 2010

k‐t Sensitivity‐encoded (k‐t SENSE) acceleration has been used to improve spatial resolution, temporal resolution, and slice coverage in first‐pass cardiac magnetic resonance myocardial perfusion imaging. This study compares the effect of investing the speed‐up afforded by k‐t SENSE acceleration in spatial or temporal resolution. Ten healthy volunteers underwent adenosine stress myocardial perfusion imaging using four saturation‐recovery gradient echo perfusion sequences: a reference sequence accelerated by sensitivity encoding (SENSE), and three k‐t SENSE–accelerated sequences with higher spatial resolution (“k‐t High”), shorter acquisition window (“k‐t Fast”), or a shared increase in both parameters (“k‐t Hybrid”) relative to the reference. Dark‐rim artifacts and image quality were analyzed. Semiquantitative myocardial perfusion reserve index (MPRI) and Fermi‐derived quantitative MPR were also calculated. The k‐t Hybrid sequence produced highest image quality scores at rest (P = 0.015). Rim artifact thickness and extent were lowest using k‐t High and k‐t Hybrid sequences (P < 0.001). There were no significant differences in MPRI and MPR values derived by each sequence. Maximizing spatial resolution by k‐t SENSE acceleration produces the greatest reduction in dark rim artifact. There is good agreement between k‐t SENSE and standard acquisition methods for semiquantitative and fully quantitative myocardial perfusion analysis. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Real‐time 3D target tracking in MRI guided focused ultrasound ablations in moving tissues
Authors: Ries Mario , de Senneville Baudouin Denis , Roujol Sébastien , Berber Yasmina , Quesson Bruno , Moonen Chrit
Published: September 2010

Magnetic resonance imaging‐guided high intensity focused ultrasound is a promising method for the noninvasive ablation of pathological tissue in abdominal organs such as liver and kidney. Due to the high perfusion rates of these organs, sustained sonications are required to achieve a sufficiently high temperature elevation to induce necrosis. However, the constant displacement of the target due to the respiratory cycle render continuous ablations challenging, since dynamic repositioning of the focal point is required. This study demonstrates subsecond 3D high intensity focused ultrasound‐beam steering under magnetic resonance‐guidance for the real‐time compensation of respiratory motion. The target is observed in 3D space by coupling rapid 2D magnetic resonance‐imaging with prospective slice tracking based on pencil‐beam navigator echoes. The magnetic resonance‐data is processed in real‐time by a computationally efficient reconstruction pipeline, which provides the position, the temperature and the thermal dose on‐the‐fly, and which feeds corrections into the high intensity focused ultrasound‐ablator. The effect of the residual update latency is reduced by using a 3D Kalman‐predictor for trajectory anticipation. The suggested method is characterized with phantom experiments and verified in vivo on porcine kidney. The results show that for update frequencies of more than 10 Hz and latencies of less then 114 msec, temperature elevations can be achieved, which are comparable to static experiments. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Age‐related changes of regional pulse wave velocity in the descending aorta using Fourier velocity encoded M‐mode
Authors: Taviani Valentina , Hickson Stacey S. , Hardy Christopher J. , McEniery Carmel M. , Patterson Andrew J. , Gillard Jonathan H. , Wilkinson Ian B. , Graves Martin J.
Published: September 2010

Aortic pulse wave velocity (PWV) is an independent determinant of cardiovascular risk. Although aortic stiffening with age is well documented, the interaction between aging and regional aortic PWV is still a debated question. We measured global and regional PWV in the descending aorta of 56 healthy subjects aged 25–76 years using a one‐dimensional, interleaved, Fourier velocity encoded pulse sequence with cylindrical excitation. Repeatability across two magnetic resonance examinations (n = 19) and accuracy against intravascular pressure measurements (n = 4) were assessed. The global PWV was found to increase nonlinearly with age. The thoracic aorta was found to stiffen the most with age (PWV [thoracic, 20–40 years] = 4.7 ± 1.1 m/s; PWV [thoracic, 60–80 years] = 7.9 ± 1.5 m/s), followed by the mid‐ (PWV [mid‐abdominal, 20–40 years] = 4.9 ± 1.3 m/s; PWV [mid‐abdominal, 60–80 years] = 7.4 ± 1.9 m/s) and distal abdominal aorta (PWV [distal abdominal, 20–40 years] = 4.8 ± 1.4 m/s; PWV [distal abdominal, 60–80 years] = 5.7 ± 1.4 m/s). Good agreement was found between repeated magnetic resonance measurements and between magnetic resonance PWVs and the gold‐standard. Fourier velocity encoded M‐mode allowed to measure global and regional PWV in the descending aorta. There was a preferential stiffening of the thoracic aorta with age, which may be due to progressive fragmentation of elastin fibers in this region. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
A Modified EPI sequence for high‐resolution imaging at ultra‐short echo time
Authors: Hetzer Stefan , Mildner Toralf , Möller Harald E.
Published: September 2010

A robust modification of echo‐planar imaging dubbed double‐shot echo‐planar imaging with center‐out trajectories and intrinsic navigation (DEPICTING) is proposed, which permits imaging at ultra‐short echo time. The k‐space data is sampled by two center‐out trajectories with a minimal delay achieving a temporal efficiency similar to conventional single‐shot echo‐planar imaging. Intersegment phase and intensity imperfections are corrected by exploiting the intrinsic navigator information from both central lines, which are subsequently averaged for image reconstruction. Phase errors induced by inhomogeneities of the main magnetic field are corrected in k‐space, recovering the superior point‐spread function achieved with center‐out trajectories. The minimal echo time (<2 msec) is nearly independent of the acquisition matrix permitting applications, which simultaneously require high spatial and temporal resolution. Examples of demonstrated applications include anatomical imaging, BOLD‐based functional brain mapping, and quantitative perfusion imaging. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Artificial perineurium to enhance nerve recovery from damage after neurolysis
Authors: Okui Nobuyuki , Yamamoto Michiro , Fukuhira Yukako , Kaneko Hiroaki , Hirata Hitoshi
Published: September 2010

We have developed a novel biodegradable poly‐lactide (PLA) film (honeycomb film) with a micropatterned porous structure on one side. We hypothesized that this film could be used as a substitute for perineurium. We used two types of thin PLA film: honeycomb film and cast film with smooth surfaces on both sides. In a rat extensive internal neurolysis model, the nerve was wrapped with honeycomb film (group H) or cast film (group CA), or left unwrapped (group C). Histological and functional analyses were performed. The honeycomb film closely attached to the nerve surface but did not adhere to surrounding tissues. In contrast, nerves in group C displayed severe adhesion to the neural bed. Mean percent wet muscle weight and motor nerve conduction velocity were significantly higher in group H than in group C. The honeycomb film prevents nerve adhesion and enhances functional recovery after extensive neurolysis. Muscle Nerve, 2010
Gender influences cardiac function in the mdx model of duchenne cardiomyopathy
Authors: Bostick Brian , Yue Yongping , Duan Dongsheng
Published: September 2010

Aged mdx mice represent an important model for studying Duchenne cardiomyopathy. Herein we compared the cardiac phenotypes of 22‐month‐old male and female mdx mice. Surprisingly, only females displayed the characteristic cardiac dilation on pressure–volume loop analysis. Female mdx mice also exhibited lower contractility, larger Q waves, and higher ratios of heart weight to body weight. Our results reveal significant gender disparity in mdx cardiac function. Gender should be considered when using the mdx model for the study of Duchenne cardiomyopathy. Muscle Nerve, 2010
Reversible conduction failure in pharyngeal‐cervical‐brachial variant of guillain‐barré syndrome
Authors: Capasso Margherita , Notturno Francesca , Manzoli Claudia , Yuki Nobuhiro , Uncini Antonino
Published: September 2010

In two patients with the pharyngeal–cervical–brachial variant (PCB) of Guillain–Barré syndrome (GBS), low amplitude distal compound muscle action potentials and partial motor conduction blocks normalized without development of excessive temporal dispersion within 4 weeks. Sensory nerve action potentials significantly improved in amplitude or, when absent, rapidly became recordable at follow‐up. Besides axonal degeneration, PCB is characterized by reversible conduction failure in both motor and sensory fibers and is in the continuous spectrum of axonal GBS subtypes. Muscle Nerve, 2010
Statin‐associated myopathy and its exacerbation with exercise
Authors: Meador Benjamin M. , Huey Kimberly A.
Published: September 2010

3‐Hydroxy‐3‐methylglutaryl coenzyme A reductase inhibitors (statins) are a common and effective treatment for hypercholesterolemia, with a low overall rate of side‐effects. The most common complication is some degree of skeletal muscle myopathy, ranging from painless serum creatine kinase elevations to rhabdomyolysis. Unfortunately, the likelihood and/or severity of complications increases with the combination of statin treatment and physical activity. The specific pathways that mediate statin‐associated myopathy are unclear, and research directly addressing the exacerbation with exercise is limited. Potential mechanisms include the induction of skeletal muscle fiber apoptosis, alterations in ubiquitin–proteasome pathway activity, mitochondrial dysfunction, and terpenoid depletion. In this review we provide an overview of research that specifically addresses the combination of statin‐associated myopathy and physical activity and highlight some deficiencies in the available literature, as well as future directions for this important subset of statin‐associated myopathy. Muscle Nerve, 2010
Efficient algorithms for multiscale modeling in porous media
Authors: Wheeler Mary F. , Wildey Tim , Xue Guangri
Published: September 2010

We describe multiscale mortar mixed finite element discretizations for second‐order elliptic and nonlinear parabolic equations modeling Darcy flow in porous media. The continuity of flux is imposed via a mortar finite element space on a coarse grid scale, while the equations in the coarse elements (or subdomains) are discretized on a fine grid scale. We discuss the construction of multiscale mortar basis and extend this concept to nonlinear interface operators. We present a multiscale preconditioning strategy to minimize the computational cost associated with construction of the multiscale mortar basis. We also discuss the use of appropriate quadrature rules and approximation spaces to reduce the saddle point system to a cell‐centered pressure scheme. In particular, we focus on multiscale mortar multipoint flux approximation method for general hexahedral grids and full tensor permeabilities. Numerical results are presented to verify the accuracy and efficiency of these approaches. Copyright © 2010 John Wiley & Sons, Ltd.
Coupled segmentation and denoising/deblurring models for hyperspectral material identification
Authors: Li Fang , Ng Michael K. , Plemmons Robert J.
Published: September 2010

A crucial aspect of spectral image analysis is the identification of the materials present in the object or scene being imaged and to quantify their abundance in the mixture. An increasingly useful approach to extracting such underlying structure is to employ image classification and object identification techniques to compressively represent the original data cubes by a set of spatially orthogonal bases and a set of spectral signatures. Owing to the increasing quantity of data usually encountered in hyperspectral data sets, effective data compressive representation is an important consideration, and noise and blur can present data analysis problems. In this paper, we develop image segmentation methods for hyperspectral space object material identification. We also couple the segmentation with a hyperspectral image data denoising/deblurring model and propose this method as an alternative to a tensor factorization methods proposed recently for space object material identification. The model provides the segmentation result and the restored image simultaneously. Numerical results show the effectiveness of our proposed combined model in hyperspectral material identification. Copyright © 2010 John Wiley & Sons, Ltd.
Taphonomy and interpretation: An analytical framework for social zooarchaeology
Authors: Orton D. C.
Published: September 2010

Taphonomy is central to many attempts to address social questions from archaeological animal remains, especially where those questions relate to practices of consumption and deposition. Without a clear analytical framework for this purpose, however, results can verge on the anecdotal. Following a review of the structure of taphonomy, this paper presents just such a framework designed to isolate archaeologically relevant patterns of behaviour through a comprehensive, quantitative analysis of numerous taphonomic variables. The typical formation processes shaping zooarchaeological assemblages are grouped into five broad stages and considered in reverse chronological order, allowing the analyst to work backwards towards the ‘death assemblage’ while identifying evidence of cultural practices. Particular attention is paid to differences between taxa, context types, phases, etc., that cannot be explained in mechanistic terms. This process is illustrated with selected data from a wider study of the Vinča (late Neolithic) site of Gomolava, Serbia, tracing the identification of one particular set of depositional practices. Copyright © 2010 John Wiley & Sons, Ltd.
A qualitative study of workers with chronic pain in Brazil and its social consequences
Authors: Silva Fabiana Caetano Martins , Sampaio Rosana Ferreira , Mancini Marisa Cotta , Luz Madel Terezinha , Alcântara Marcus Alessandro
Published: September 2010

Chronic pain contributes towards less diversified participation centred on household activities, fewer social relationships and smaller number of recreational activities. The aim of the study was to further investigate the effects of chronic pain on participation, focusing on how workers deal with the experienced restrictions. Ten workers with chronic pain participated in the survey, which was conducted with qualitative interviews. Analyses of thematic units revealed that chronic pain has consequences for participation, leading to work restrictions and loss of social roles. Social relationships tend to be limited to family, and workers become isolated from other social groups. The rebuilding of participants' lives was a counterpoint to the identified social rupture. The narratives revealed strategies for dealing with pain, attempts at reorganizing their daily activities and formulating new plans. Understanding what resources individuals use to cope with their difficulties allow occupational therapists to plan client‐centred treatment goals. A limitation of the study was to involve employees of very similar socio‐economic classes. Studies directed to understanding the relationship between social support and the reconstruction of participation must be conducted to further advance knowledge on possible mechanisms underlying social participation among workers with chronic pain. Copyright © 2010 John Wiley & Sons, Ltd.
Regulation of tissue‐ and stimulus‐specific cell fate decisions byp53 in vivo
Authors: Jackson James G , Post Sean M , Lozano Guillermina
Published: September 2010

The tumour suppressorp53pathway is often inactivated by multiple mechanisms in the genesis of human cancers. Aberrant cellular proliferation, DNA damage, hypoxia, and ribosomal stress cause activation of thep53tumour suppressor with multiple possible consequences to the cell: cell death, cell cycle arrest, or senescence. These mechanisms ultimately ensure that the cell does not replicate, and are thus potent tumour suppressor mechanisms. An important question that has eluded the field is howp53makes these cell fate decisions. This review summarizes the current status of knowledge regardingp53‐mediated stress and tissue‐dependent cell fate decisions in mouse models and human tumours. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The role of mutant p53 in human cancer
Authors: Goh Amanda M , Coffill Cynthia R , Lane David P
Published: September 2010

Mutations in the TP53 (p53) gene are present in a large fraction of human tumours, which frequently express mutant p53 proteins at high but heterogeneous levels. The clinical significance of this protein accumulation remains clouded. Mouse models bearing knock‐in mutations of p53 have established that the mutant p53 proteins can drive tumour formation, invasion and metastasis through dominant negative inhibition of wild‐type p53 as well as through gain of function or ‘neomorphic’ activities that can inhibit or activate the function of other proteins. These models have also shown that mutation alone does not confer stability, so the variable staining of mutant proteins seen in human cancers reflects tumour‐specific activation of p53‐stabilizing pathways. Blocking the accumulation and activity of mutant p53 proteins may thus provide novel cancer therapeutic and diagnostic targets, but their induction by chemotherapy may paradoxically limit the effectiveness of these treatments. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The dynamic roles of TGF‐β in cancer
Authors: Meulmeester Erik , ten Dijke Peter
Published: September 2010

The transforming growth factor‐β (TGF‐β) signalling pathway plays a critical and dual role in the progression of human cancer. During the early phase of tumour progression, TGF‐β acts as a tumour suppressor, exemplified by deletions or mutations in the core components of the TGF‐β signalling pathway. On the contrary, TGF‐β also promotes processes that support tumour progression such as tumour cell invasion, dissemination, and immune evasion. Consequently, the functional outcome of the TGF‐β response is strongly context‐dependent including cell, tissue, and cancer type. In this review, we describe the molecular signalling pathways employed by TGF‐β in cancer and how these, when perturbed, may lead to the development of cancer. Concomitantly with our increased appreciation of the molecular mechanisms that govern TGF‐β signalling, the potential to therapeutically target specific oncogenic sub‐arms of the TGF‐β pathway increases. Indeed, clinical trials with systemic TGF‐β signalling inhibitors for treatment of cancer patients have been initiated. However, considering the important role of TGF‐β in cardiovascular and many other tissues, careful screening of patients is warranted to minimize unwanted on‐target side effects. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Betel‐derived alkaloid up‐regulates keratinocyte alphavbeta6 integrin expression and promotes oral submucous fibrosis
Authors: Moutasim Karwan A , Jenei Veronika , Sapienza Karen , Marsh Daniel , Weinreb Paul H , Violette Shelia M , Lewis Mark P , Marshall John F , Fortune Farida , Tilakaratne Waninayaka M , Hart Ian R , Thomas Gareth J
Published: September 2010

Oral submucous fibrosis (OSF) is a premalignant, fibrosing disorder of the mouth, pharynx, and oesophagus, with a malignant transformation rate of 7–13%. OSF is strongly associated with areca (betel) nut chewing and worldwide, over 5 million people are affected. As αvβ6 integrin is capable of promoting both tissue fibrosis and carcinoma invasion, we examined its expression in fibroepithelial hyperplasia and OSF. αvβ6 was markedly up‐regulated in OSF, with high expression detected in 22 of 41 cases (p < 0.001). We investigated the functional role of αvβ6 using oral keratinocyte‐derived cells genetically modified to express high αvβ6 (VB6), and also NTERT‐immortalized oral keratinocytes, which express low αvβ6 (OKF6/TERT‐1). VB6 cells showed significant αvβ6‐dependent activation of TGF‐β1, which induced transdifferentiation of oral fibroblasts into myofibroblasts and resulted in up‐regulation of genes associated with tissue fibrosis. These experimental in vitro findings were confirmed using human clinical samples, where we showed that the stroma of OSF contained myofibroblasts and that TGF‐β1‐dependent Smad signalling was detectable both in keratinocytes and in myofibroblasts. We also found that arecoline, the major alkaloid of areca nuts, up‐regulated keratinocyte αvβ6 expression. This was modulated through the M4 muscarinic acetylcholine receptor and was suppressed by the M4 antagonist, tropicamide. Arecoline‐dependent αvβ6 up‐regulation promoted keratinocyte migration and induced invasion, raising the possibility that this mechanism may support malignant transformation. Over 80% of OSF‐related oral cancers examined had moderate/high αvβ6 expression. These data suggest that the pathogenesis of OSF may be epithelial‐driven and involve arecoline‐dependent up‐regulation of αvβ6 integrin. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
New insights in sarcoma oncogenesis: a comprehensive analysis of a large series of 160 soft tissue sarcomas with complex genomics
Authors: Gibault Laure , Pérot Gaëlle , Chibon Frédéric , Bonnin Sarah , Lagarde Pauline , Terrier Philippe , Coindre Jean‐Michel , Aurias Alain
Published: September 2010

Adult soft tissue sarcomas (STS) are rare tumours of mesenchymal lineage. Based on cytogenetic and comparative genomic hybridization (CGH) data, they can be divided into ‘STS with simple genomics’, displaying a characteristic genetic alteration, and ‘STS with complex genomics’ (SCG), where multiple genomic alterations occur. This latter group is mostly composed of leiomyosarcomas (LMS) and pleiomorphic undifferentiated tumours previously labelled as ‘malignant fibrous histiocytomas’ (MFH), corresponding in fact to myxofibrosarcomas (MFS), pleiomorphic liposarcomas/rhabdomyosarcomas (P‐LPS, P‐RMS), and undifferentiated pleiomorphic sarcomas (UPS). Their pathobiology is still not well understood, leading to challenges in diagnosis and therapeutic management. We report here a comprehensive study encompassing array‐CGH and transcriptome analysis data of a large series of 160 SCG. Non‐supervised clustering of transcriptome data led to the identification of five groups of tumours, one of them (group A) corresponding to well‐differentiated LMS and the other four (B–E) to ‘MFH’ and poorly differentiated LMS. Welch analysis of transcriptome data in these groups allowed us to retrieve several genes of potential interest. Among them, RB1 alteration is a constant thread in SCG, often associated with RBL2 loss. PTEN tumour suppressor deletion would also stand out as a major recurrent event, especially in groups A, C, and D. The WNT canonical pathway could be potentially involved, as demonstrated by up‐regulation of one of its inhibitors, DKK1, in groups D and E, whereas DKK1 is significantly down‐regulated in groups A, B, and C. These data suggest a very complex interplay between pathways downstream of PTEN and the WNT canonical pathway, providing new hints about SCG pathobiology and their potential therapeutic targets. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Notch signalling in T‐cell lymphoblastic leukaemia/lymphoma and other haematological malignancies
Authors: Aster Jon C , Blacklow Stephen C , Pear Warren S
Published: September 2010

Notch receptors participate in a highly conserved signalling pathway that regulates normal development and tissue homeostasis in a context‐ and dose‐dependent manner. Deregulated Notch signalling has been implicated in many diseases, but the clearest example of a pathogenic role is found in T‐cell lymphoblastic leukaemia/lymphoma (T‐LL), in which the majority of human and murine tumours have acquired mutations that lead to aberrant increases in Notch1 signalling. Remarkably, it appears that the selective pressure for Notch mutations is virtually unique among cancers to T‐LL, presumably reflecting a special context‐dependent role for Notch in normal T‐cell progenitors. Nevertheless, there are some recent reports suggesting that Notch signalling has subtle, yet important roles in other forms of haematological malignancy as well. Here, we review the role of Notch signalling in various blood cancers, focusing on T‐LL with an eye towards targeted therapeutics. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Clinical cancer genomics: how soon is now?
Authors: Taylor Barry S. , Ladanyi Marc
Published: September 2010

Germline and somatic alterations in DNA mediate the genesis and progression of human cancers. Not only do these events represent the molecular underpinnings of disease but many are of immense clinical importance as diagnostic markers and therapeutic targets. In fact, rapidly evolving sequencing technologies have empowered enormous growth in the breadth and depth of cancer genome characterization. Whether these will impact routine clinical practice and the treatment of disease is no longer debatable, but how precisely this will happen is a source of ongoing speculation and development. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.