bluuebunny/crossref_metadata_2025_split huggingface dataset:
Passive sampling methods for contaminated sediments: State of the science for organic contaminants
Authors: Lydy Michael J , Landrum Peter F , Oen Amy MP , Allinson Mayumi , Smedes Foppe , Harwood Amanda D , Li Huizhen , Maruya Keith A , Liu Jingfu 
Published: November 2013

Abstract
This manuscript surveys the literature on passive sampler methods (PSMs) used in contaminated sediments to assess the chemical activity of organic contaminants. The chemical activity in turn dictates the reactivity and bioavailability of contaminants in sediment. Approaches to measure specific binding of compounds to sediment components, for example, amorphous carbon or specific types of reduced carbon, and the associated partition coefficients are difficult to determine, particularly for native sediment. Thus, the development of PSMs that represent the chemical activity of complex compound–sediment interactions, expressed as the freely dissolved contaminant concentration in porewater (Cfree), offer a better proxy for endpoints of concern, such as reactivity, bioaccumulation, and toxicity. Passive sampling methods have estimated Cfree using both kinetic and equilibrium operating modes and used various polymers as the sorbing phase, for example, polydimethylsiloxane, polyethylene, and polyoxymethylene in various configurations, such as sheets, coated fibers, or vials containing thin films. These PSMs have been applied in laboratory exposures and field deployments covering a variety of spatial and temporal scales. A wide range of calibration conditions exist in the literature to estimate Cfree, but consensus values have not been established. The most critical criteria are the partition coefficient between water and the polymer phase and the equilibrium status of the sampler. In addition, the PSM must not appreciably deplete Cfree in the porewater. Some of the future challenges include establishing a standard approach for PSM measurements, correcting for nonequilibrium conditions, establishing guidance for selection and implementation of PSMs, and translating and applying data collected by PSMs. Integr Environ Assess Manag 2014;10:167–178. © 2014 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC.
Key Points
This manuscript reviews 90 recent citations on passive sampling methods (PSMs) that target the freely dissolved concentration (Cfree) of a contaminant in sediment. PSMs employing various polymers and configurations have been used in lab and field applications to quantify Cfree, a better proxy for bioaccumulation and toxicity than bulk sediment (“total”) concentration. Standardization and guidance on proper selection and application of PSMs is needed to expand their utility in assessment and management of contaminated sediments.
Skeletal Structure in Postmenopausal Women With Osteopenia and Fractures Is Characterized by Abnormal Trabecular Plates and Cortical Thinning
Authors: Stein Emily M , Kepley Anna , Walker Marcella , Nickolas Thomas L , Nishiyama Kyle , Zhou Bin , Liu X Sherry , McMahon Donald J , Zhang Chiyuan , Boutroy Stephanie , Cosman Felicia , Nieves Jeri , Guo X Edward , Shane Elizabeth 
Published: November 2013

ABSTRACT

The majority of fragility fractures occur in women with osteopenia rather than osteoporosis as determined by dual-energy X-ray absorptiometry (DXA). However, it is difficult to identify which women with osteopenia are at greatest risk. We performed this study to determine whether osteopenic women with and without fractures had differences in trabecular morphology and biomechanical properties of bone. We hypothesized that women with fractures would have fewer trabecular plates, less trabecular connectivity, and lower stiffness. We enrolled 117 postmenopausal women with osteopenia by DXA (mean age 66 years; 58 with fragility fractures and 59 nonfractured controls). All had areal bone mineral density (aBMD) measured by DXA. Trabecular and cortical volumetric bone mineral density (vBMD), trabecular microarchitecture, and cortical porosity were measured by high-resolution peripheral computed tomography (HR-pQCT) of the distal radius and tibia. HR-pQCT scans were subjected to finite element analysis to estimate whole bone stiffness and individual trabecula segmentation (ITS) to evaluate trabecular type (as plate or rod), orientation, and connectivity. Groups had similar age, race, body mass index (BMI), and mean T-scores. Fracture subjects had lower cortical and trabecular vBMD, thinner cortices, and thinner, more widely separated trabeculae. By ITS, fracture subjects had fewer trabecular plates, less axially aligned trabeculae, and less trabecular connectivity. Whole bone stiffness was lower in women with fractures. Cortical porosity did not differ. Differences in cortical bone were found at both sites, whereas trabecular differences were more pronounced at the radius. In summary, postmenopausal women with osteopenia and fractures had lower cortical and trabecular vBMD; thinner, more widely separated and rodlike trabecular structure; less trabecular connectivity; and lower whole bone stiffness compared with controls, despite similar aBMD by DXA. Our results suggest that in addition to trabecular and cortical bone loss, changes in plate and rod structure may be important mechanisms of fracture in postmenopausal women with osteopenia. © 2014 American Society for Bone and Mineral Research.
Laser‐induced Breakdown Spectroscopy of Liquid Droplets Based on Plasma‐induced Current Correlation
Authors: Huang Jer‐Shing , Lin King‐Chuen 
Published: November 2013

AbstractThe main limitation for laser‐induced breakdown spectroscopy (LIBS) to analyse liquid sample remains the poor reproducibility due to shot‐to‐shot signal fluctuation. To resolve this problem, we employ electrospray scheme for liquid sample introduction and develop a correlation method based on plasma‐induced current normalization. Since the plasma‐induced current is proportional to the amount of solvent broken down by the laser pulses, it serves as an excellent reference signal for the removal of shot‐to‐shot signal fluctuation. Our current normalization method is robust and resistive to the interference of salt matrix. The limit of detection (LOD) obtained for alkali‐elements reaches sub‐milligram per litre (<1 mg/L) even with the matrix salts added up to 2000 mg/L. We also investigate the effect of laser wavelength and pulse energy on different normalization methods. We show that background normalization requires the knowledge of plasma temperature to retrieve the correlation linearity, whereas current normalization already takes into account the plasma temperature and shows linearity over wide range of laser pulse energy. With current normalization, the resultant LOD of Na sample is about 20 times better than that obtained by LIB/background normalization. In combination with a flow‐injection system for preconcentration and matrix separation, we demonstrate sensitive on‐line analysis of aluminium salt in liquid droplets. We obtained a linear dynamic range of more than two orders of magnitude and the LOD reaches 1.5 mg/L, about ten times lower than those achieved without preconcentration.
Acute effects of splint immobilization of the forearm on in vivo microcirculation and histomorphology of the human skin
Authors: Altintas A.A. , Vogt P.M. , Altintas M.A. 
Published: November 2013

ABSTRACTBACKGROUND: Splint immobilization of the forearm is often performed in clinical practice. Previous studies investigated the effect of immobilization on bone, cartilage, muscle, and tendon, however, the acute effects on human skin microcirculation and histomorphology remains elusive. METHODS: In 12 healthy, nonsmoking individuals (aged 29.7 ± 9.1 years) a randomly selected forearm was immobilized by splinting for 72 h, whereas the other forearm served as control. In vivo Reflectance‐Mode Confocal‐Microscopy (RMCM) was performed prior (baseline value) and postimmobilization to evaluate: quantitative blood cell flow; density of functional dermal capillaries; epidermal thickness; and granular cell size. RESULTS: At 72h forearm immobilization, quantitative blood cell flow was significantly reduced (42.86 ± 3.68 cells/min) compared to the control blood flow (53.11 ± 3.68 cells/min, P < 0.05) and dermal capillaries indicates less functional density (5.73 ± 0.63 capillaries/mm2) compared to the controls (7.04 ± 0.81 capillaries/mm2, P < 0.05). Histometric assessment reveals significantly thinner epidermis following immobilization compared to the control site (40.02 ± 2.91 vs. 46.64±3.09 µm, P < 0.05). Granular cell size was significantly altered at 72 h splinting (730.1 ± 42.53 µm2) compared to the control cell size at 770.2 ± 38.21 µm2. Comparison of baseline values of both forearms indicate statistically insignificance (P > 0.05) for each parameter. CONCLUSION: At 72 h splint immobilization, for the first time, significant adaptive mechanisms were evaluated on human skin microcirculation and histomorphology using in vivo RMCM. These adaptations may be considered as an incipient atrophy of the human skin. Long‐term effects of immobilization including the regenerative potential should be evaluated in further RMCM studies. Microsc. Res. Tech. 77:99–103, 2014. © 2013 Wiley Periodicals, Inc.
SCPP genes in the coelacanth: Tissue mineralization genes shared by sarcopterygians
Authors: Kawasaki Kazuhiko , Amemiya Chris T. 
Published: November 2013

ABSTRACTThe coelacanth is the basal‐most extant sarcopterygian that has teeth and tooth‐like structures, comprising bone, dentin, and enamel or enameloid. Formation of these tissues involves many members of the secretory calcium‐binding protein (SCPP) family. In tetrapods, acidic‐residue‐rich SCPPs are used in mineralization of bone and dentin, whereas Pro/Gln‐rich SCPPs participate in enamel formation. Teleosts also employ many SCPPs for tissue mineralization. Nevertheless, the repertoire of SCPPs is largely different in teleosts and tetrapods; hence, filling this gap would be critical to elucidate early evolution of mineralized tissues in osteichthyans. In the present study, we searched for SCPP genes in the coelacanth genome and identified 11, of which two have clear orthologs in both tetrapods and teleosts, seven only in tetrapods, and two in neither of them. Given the divergence times of these vertebrate lineages, our discovery of this many SCPP genes shared between the coelacanth and tetrapods, but not with teleosts, suggests a complicated evolutionary scheme of SCPP genes in early osteichthyans. Our investigation also revealed both conserved and derived characteristics of SCPPs in the coelacanth and other vertebrates. Notably, acidic SCPPs independently evolved various acidic repeats in different lineages, while maintaining high acidity, presumably important for interactions with calcium. Furthermore, the three Pro/Gln‐rich SCPP genes, required for mineralizing enamel matrix and confirmed only in tetrapods, were all identified in the coelacanth, strongly suggesting that enamel is equivalent in the coelacanth and tetrapods. This finding corroborates the previous proposition that true enamel evolved much earlier than the origin of tetrapods.J. Exp. Zool. (Mol. Dev. Evol.) 322B: 390–402, 2014. © 2013 Wiley Periodicals, Inc.
The impact of facecards on patients' knowledge, satisfaction, trust, and agreement with hospital physicians: A pilot study
Authors: Simons Yael , Caprio Timothy , Furiasse Nicholas , Kriss Michael , Williams Mark V. , O'Leary Kevin J. 
Published: November 2013

BACKGROUNDSimple interventions such as facecards can improve patients' knowledge of names and roles of hospital physicians, but the effect on other aspects of the patient‐physician relationship is not clear.OBJECTIVETo pilot an intervention to improve familiarity with physicians and assess its potential to improve patients' satisfaction, trust, and agreement with physicians.DESIGNCluster randomized controlled trial assessing the impact of physician facecards. Physician facecards included pictures of physicians and descriptions of their roles. We performed structured interviews of randomly selected patients to assess outcomes.SETTINGOne of 2 similar hospitalist units and 1 of 2 teaching‐service units in a large teaching hospital were randomly selected to implement the intervention.MEASUREMENTSSatisfaction with physician communication and overall hospital care was assessed using the Hospital Consumer Assessment of Healthcare Providers and Systems. Trust and agreement were each assessed through instruments used in prior research.RESULTSOverall, 138 patients completed interviews, with no differences in age, sex, or race between those receiving facecards and those not. More patients who received facecards correctly identified ≥1 hospital physician (89.1% vs 51.1%; P < 0.01) and their role (67.4% vs 16.3%; P < 0.01) than patients who had not received facecards. Patients had high baseline levels of satisfaction, trust, and agreement with hospital physicians, and we found no significant differences with the use of facecards.CONCLUSIONSPhysician facecards improved patients' knowledge of the names and roles of hospital physicians. Larger studies are needed to assess the impact on satisfaction, trust, and agreement with physicians. Journal of Hospital Medicine 2014;9:137–141. © 2013 Society of Hospital Medicine
Quantification of amide proton transfer effect pre‐ and post‐gadolinium contrast agent administration
Authors: Tee Yee Kai , Donahue Manus J. , Harston George W.J. , Payne Stephen J. , Chappell Michael A. 
Published: November 2013

PurposeTo compare quantification of the amide proton transfer (APT) effect pre‐ and post‐gadolinium contrast agent (Gd) administration in order to establish to what extent Gd alters quantification of the APT effect.Materials and MethodsFour patients with internal carotid stenosis were recruited. APT imaging was acquired pre‐ and post‐contrast in two sessions (before and after surgery) to assess the extent of relaxation time, T1, change on APT effect calculated using magnetization transfer ratio asymmetry analysis at offsets of ±3.5 ppm relative to water resonance. Statistical and modeling evaluations were performed on the pre‐ and post‐contrast APT effect to study the sensitivity to contrast administration.ResultsBefore surgery, the post‐contrast T1 was estimated to drop <10% of the pre‐value for the majority of the patients. After surgery, higher post‐contrast T1 reductions were observed in all the patients (maximum decrease was about 20% of the pre‐value). Consistent differences between pre‐ and post‐contrast were seen in the APT effect quantified using the asymmetry measure in most regions of the brain, with significant differences found in the white matter at the group level and in 25% of the individual patient results.ConclusionAPT imaging should be performed prior to Gd administration to avoid potential misinterpretation of the APT effect. J. Magn. Reson. Imaging 2014;40:832–838. © 2013 Wiley Periodicals, Inc.
Morphology and function: MR pineal volume and melatonin level in human saliva are correlated
Authors: Liebrich Luisa‐Sophie , Schredl Michael , Findeisen Peter , Groden Christoph , Bumb Jan Malte , Nölte Ingo S. 
Published: November 2013

PurposeTo investigate the relation between circadian saliva melatonin levels and pineal volume as determined by MRI. Plasma melatonin levels follow a circadian rhythm with a high interindividual variability.Materials and MethodsIn 103 healthy individuals saliva melatonin levels were determined at four time points within 24 h and MRI was performed once (3.0 Tesla, including three‐dimensional T2 turbo spin echo [3D‐T2‐TSE], susceptibility‐weighted imaging [SWI]). Pineal volume as well as cyst volume were assessed from multiplanar reconstructed 3D‐T2‐TSE images. Pineal calcification volume tissue was determined on SWI. To correct for hormonal inactive pineal tissue, cystic and calcified areas were excluded. Sleep quality was assessed with the Landeck Inventory for sleep quality disturbance.ResultsSolid and uncalcified pineal volume correlated to melatonin maximum (r = 0.28; P < 0.05) and area under the curve (r = 0.29; P < 0.05). Of interest, solid and uncalcified pineal volume correlated negatively with the sleep rhythm disturbances subscore (r = −0.17; P < 0.05) despite a very homogenous population.ConclusionUncalcified solid pineal tissue measured by 3D‐T2‐TSE and SWI is related to human saliva melatonin levels. The analysis of the sleep quality and pineal volume suggests a linkage between better sleep quality and hormonal active pineal tissue. J. Magn. Reson. Imaging 2014;40:966–971. © 2013 Wiley Periodicals, Inc.
Response to chemotherapy in gastric adenocarcinoma with diffusion‐weighted MRI and 18F‐FDG‐PET/CT: Correlation of apparent diffusion coefficient and partial volume corrected standardized uptake value with histological tumor regression grade
Authors: Giganti Francesco , De Cobelli Francesco , Canevari Carla , Orsenigo Elena , Gallivanone Francesca , Esposito Antonio , Castiglioni Isabella , Ambrosi Alessandro , Albarello Luca , Mazza Elena , Gianolli Luigi , Staudacher Carlo , Del Maschio Alessandro 
Published: November 2013

PurposeTo assess whether changes in diffusion‐weighted MRI (DW‐MRI) and 18F‐fluoro‐2‐deoxyglucose positron emission tomography/computed tomography (18F‐FDG PET/CT), correlate with treatment response to neoadjuvant therapy (NT), as expressed by tumor regression grade (TRG), from locally advanced gastric adenocarcinoma (GA).Materials and MethodsSeventeen patients underwent both DW‐MRI and 18F‐FDG‐PET/CT scans before and after the end of NT. Apparent diffusion coefficient (ADC) and mean standardized uptake value (SUV) corrected for partial volume effect (PVC‐SUVBW‐mean) were evaluated and compared with histopathological TRG.ResultsPre‐ and post‐NT and percentage changes for ADC and PVC‐SUVBW‐mean were assessed. Post‐NT ADC and ΔADC showed a significant inverse correlation with TRG (r = −0.71; P = 0.0011 and r = −0.78; P = 0.00020, respectively) and significant differences in their mean values were found between responders (TRG 1–2‐3) and nonresponders (TRG 4–5) (P = 0.0009; P = 0.000082, respectively). No correlations with TRG were found for pre‐NT ADC and for all PVC‐SUVBW‐mean values as well as between ΔADC and Δ PVC‐SUVBW‐mean.ConclusionDW‐MRI seems more accurate than 18F‐FDG‐PET/CT and ADC modifications may represent a reproducible tool to assess tumor response for GA. J. Magn. Reson. Imaging 2014;40:1147–1157. © 2013 Wiley Periodicals, Inc.
Navigator flip angle optimization for free‐breathing T1‐weighted hepatobiliary phase imaging with gadoxetic acid
Authors: Kühn Jens‐P. , Holmes James H. , Brau Anja C.S. , Iwadate Yuji , Hernando Diego , Reeder Scott B. 
Published: November 2013

PurposeTo characterize and optimize the navigator‐flip angle (FA), and the influence of imaging‐FA on optimizing liver/lung contrast of the navigator profile, while avoiding visible navigator saturation artifacts, for hepatobiliary phase gadoxetic acid‐enhanced MRI.Materials and MethodsTen volunteers; six men, four women; ages 37.1 ± 11.0 years underwent navigator‐gated three‐dimensional (3D) ‐spoiled‐gradient‐echo sequences in randomized combinations of imaging‐FA (10°/30°) and navigator‐FA (10‐90°) before contrast and 20 min after injection of gadoxetic acid at 3 Tesla. The signal intensities of the liver and lung were measured from navigator profiles. Furthermore, the intensity of saturation artifacts for each navigator FA was quantified using measurements of relative contrast at the artifact location.ResultsFor the postcontrast images, the optimal navigator FA was 90°. However, saturation artifacts were highly dependent on the imaging‐FA and the presence of gadolinium contrast. A smaller imaging‐FA of 10° led to greater saturation artifacts for both pre‐ and postcontrast, and saturation artifacts worsen with increasing navigator‐FA. Using a higher imaging‐FA of 30°, saturation artifacts are ignorable over the entire range of navigator‐FA.ConclusionFor navigator‐gated gadoxetic acid‐enhanced hepatobiliary imaging, navigator‐FA of 90° and imaging‐FA of 30° provide an optimal balance with maximum navigator liver/lung contrast while avoiding visible imaging saturation artifacts.J. Magn. Reson. Imaging 2014;40:1129–1136. © 2013 Wiley Periodicals, Inc.
Short‐term exercise‐induced changes in hydration state of healthy achilles tendons can be visualized by effects of off‐resonant radiofrequency saturation in a three‐dimensional ultrashort echo time MRI sequence applied at 3 tesla
Authors: Syha Roland , Springer Fabian , Grözinger Gerd , Würslin Christian , Ipach Ingmar , Ketelsen Dominik , Schabel Christoph , Gebhard Harry , Hein Tobias , Martirosian Petros , Schick Fritz , Claussen Claus D. , Grosse Ulrich 
Published: November 2013

PurposeOff‐resonant RF saturation influences signal intensity dependent on free and bound water fractions as well as the macromolecular content. The extent of interaction between these compartments can be evaluated by using the off‐resonance saturation ratio (OSR). Combined with UTE sequences quantification of OSR even in tendinous tissues with extremely fast signal decay is possible. The aim of this prospective study was to investigate short‐term exercise‐induced effects of hydration state of the Achilles tendon by means of OSR and tendon volume.Materials and MethodsMeasurements of OSR and tendon volume before and after ankle‐straining activity were performed in seven healthy male volunteers (median age 29 years) using a 3D UTE sequence with implemented off‐resonance saturation pulse at 3T (off‐resonance frequency 2/3 kHz) and by an automated contour detection in isotropic T2‐weighted MR images with sub‐millimeter resolution, respectively. Different tendon regions were evaluated. Reproducibility of OSR was measured in subsequent imaging sets. Root‐mean‐square‐deviation (RMSD) and coefficient of variations (CV) were determined.ResultsRMSD of OSR in resting position were between 0.006 and 0.01 for different tendon regions and off‐resonance frequencies (CV 2 to 3%). A significant increase (P < 0.05) of OSR after exercise was seen in all tendon regions except at the insertion (off‐resonance frequency 3 kHz). Tendon volume was decreased significantly after ankle‐straining activity (P = 0.003).ConclusionThe observed decreased tendon volume and increased OSR directly after exercise indicates a short‐term change in tendinous proton compartments, most likely a loss of free water molecules within the tendon.J. Magn. Reson. Imaging 2014;40:1400–1407. © 2013 Wiley Periodicals, Inc.
Diagnostic efficacy of the diffusion weighted imaging in the characterization of different types of breast lesions
Authors: Kul Sibel , Eyuboglu Ilker , Cansu Aysegul , Alhan Etem 
Published: November 2013

PurposeTo evaluate the diagnostic efficacy of quantitative Diffusion‐weighted imaging (DWI) in the characterization of breast lesions of mass and non‐mass enhancement (NME) types.Materials and MethodsAfter the institutional review board gave approval, DWI exams of 267 women with 212 suspicious masses, 73 NMEs were retrospectively analyzed. Apparent diffusion coefficients (ADCs) of benign and malignant lesions were compared. Cutoff values were obtained by receiver operating characteristics analysis. Diagnostic accuracies of DWI for masses and NMEs were compared with the use of Chi‐square test. The effect of the lesions histologic subtypes and size on diagnostic accuracies was evaluated.ResultsADCs were significantly lower in malignants than in benigns for both masses (0.75 versus 1.21 × 10−3 mm2/s,) and NMEs (0.79 versus 1.06 × 10−3 mm2/s)(P < 0.001). Cutoff value was 0.90 × 10−3 mm2/s for both lesion types. The accuracy of DWI was lower in NMEs (76.7%) than masses (89.2%) (P = 0.008) unrelated to lesion size. There was more overlap in ADCs of the benign and malignant NMEs due to the lower ADCs of the benign histologies of this group.ConclusionDespite the lower diagnostic accuracy of DWI in NMEs, it could be helpful in the characterization of suspicious breast lesions of both mass and NME types.J. Magn. Reson. Imaging 2014;40:1158–1164. © 2013 Wiley Periodicals, Inc.