bluuebunny/crossref_metadata_2025 huggingface dataset:
Global ozone–CO correlations from OMI and AIRS: constraints on tropospheric ozone sources
Authors: Kim P. S. , Jacob D. J. , Liu X. , Warner J. X. , Yang K. , Chance K.
Published: April 2013

Abstract. We present a global data set of free tropospheric ozone–CO correlations with 2° × 2.5° spatial resolution from the Ozone Monitoring Instrument (OMI) and Atmospheric Infrared Sounder (AIRS) satellite instruments for each season of 2008. OMI and AIRS have near daily global coverage of ozone and CO respectively and observe coincident scenes with similar vertical sensitivities. The resulting ozone–CO correlations are highly statistically significant (positive or negative) in most regions of the world, and are less noisy than previous satellite-based studies that used sparser data. We interpret the observed ozone–CO correlations with the GEOS-Chem chemical transport model to infer constraints on ozone sources. Driving GEOS-Chem with different meteorological fields generally shows consistent ozone–CO correlation patterns, except in some tropical regions where the correlations are strongly sensitive to model transport error associated with deep convection. GEOS-Chem reproduces the general structure of the observed ozone–CO correlations and regression slopes (dO3/dCO), although there are some large regional discrepancies. We examine the model sensitivity of dO3/dCO to different ozone sources (combustion, biosphere, stratosphere, and lightning NOx) by correlating the ozone change from that source to CO from the standard simulation. The model reproduces the observed positive dO3/dCO in the extratropical Northern Hemisphere in spring–summer, driven by combustion sources. Stratospheric influence there is also associated with a positive dO3/dCO because of the interweaving of stratospheric downwelling with continental outflow. The well-known ozone maximum over the tropical South Atlantic is associated with negative dO3/dCO in the observations; this feature is reproduced in GEOS-Chem and supports a dominant contribution from lightning to the ozone maximum. A~major model discrepancy is found over the Northeast Pacific in summer-fall where dO3/dCO is positive in the observations but negative in the model, for all ozone sources. We suggest that this reflects a model overestimate of lightning at northern mid-latitudes combined with an underestimate of the East Asian CO source.
Evaluation of roadway Gaussian plume models with large-scale measurement campaigns
Authors: Briant R. , Seigneur C. , Gadrat M. , Bugajny C.
Published: April 2013

Abstract. Gaussian models are commonly used to simulate atmospheric pollutant dispersion near sources because they provide an efficient compromise between reasonable accuracy and manageable computational time. The Gaussian dispersion formula provides an exact solution to the atmospheric diffusion equation for the dispersion of a pollutant emitted from a point source. However, the Gaussian dispersion formula for a line source, which is convenient to model emissions from on-road traffic, is exact only when the wind is perpendicular to the line source. A novel approach that reduces the error in the line source formula when the wind direction is not perpendicular to the road was recently developed. This model is used to simulate NOx concentrations in a large case study (1371 road sections representing about 831 km). NO2, NO and O3 concentrations are then computed using the photostationary-state approximation. NO2 concentrations are compared with measurements made at 242 locations in the domain area. Model performance is satisfactory with mean normalised errors of 22% (winter month) to 31% (summer month). Results obtained here are also compared with those obtained with a previous formulation and with a standard model used for regulatory applications, ADMS-Urban. Discrepancies among the results obtained with those models are discussed.
The snowdrift effect on snow deposition: insights from a comparison of a snow pit profile and meteorological observations
Authors: Ding M. , Xiao C. , Zhang R. , Qin D. , Jin B. , Sun B. , Bian L. , Ming J. , Li C. , Xie A. , Yang W. , Ma Y.
Published: April 2013

Abstract. A high-frequency and precise ultrasonic sounder was used to record precipitated/deposited snow and drift events over a 3 yr period (17 January 2005 to 4 January 2008) at the Eagle automatic weather station (AWS) site. Through a comparison of the meteorological data with snow pit chemical/isotopic dating results, the snowdrift process effect during snow accumulation was assessed. We believe that ice/firn cores are the most important proxies of climate and the environment because of their high resolution and their preservation of historical greenhouse gas levels, although their limitations and measurement uncertainties must be taken into account, due to the event-driven snow dominates the snow deposition. This study found a difference between two dating results of up to 12 months for a ~ 95 cm snow pit, where the annual snow accumulation rate is 30.3 cm. A weakness is also indicated when simulating the surface mass balance in Antarctica.
Who’s Afraid of the Big, Bad European Public Prosecutor?
Authors: Spencer John R.
Published: March 2013

In 1997 the idea of a European Public Prosecutor was floated in the Corpus Juris Project as one of a series of measures designed to ensure that fraud on the Community budget would be detected and punished. This chapter describes how in the UK the proposal was misrepresented by the eurosceptic press, and how Parliament reacted to the distorted version by changing the law to render any future participation by the UK in a project to create a European Public Prosecutor practically impossible.
Rythmomimisme et gestuelle dansée
Authors: Plancke Carine
Published: April 2013

Une caractéristique de la performance dansée est d’orienter l’attention sur le mouvement en tant que tel et d’induire une conscience proprioceptive aiguë. Elle a dès lors le potentiel de faire apparaître dans son accomplissement même la double action d’incorporation et de dilatation de la gestuelle humaine, identifiée par Marcel Jousse, ainsi que le rapport mimétique de l’individu au monde qui s’y réalise. Cet argument est exploré pour l’ikoku des Punu du Congo-Brazzaville. Dans cette danse qui célèbre la fertilité, un va-et-vient entre des danseurs de sexe différent donne lieu à une phase d’animation collective suivie d’une danse en couple. Par l’attention portée au corps en train de bouger à l’image de l’autre, qui est à la fois l’autre danseur et le génie de l’eau, garant du bien-être social, la performance met en acte le processus rythmomimique d’internalisation et d’externalisation de l’univers sociocosmique punu en tant qu’il est élaboré à la fois autour de la notion d’une complémentarité des sexes et de celle d’un enveloppement maternel.
Synthesis of novel thiophene‐based chiral ligands and their application in asymmetric Henry reaction
Authors: Ebru Aydin A.
Published: March 2013

Novel chiral thiolated amino alcohols were synthesized from norephedrine and thiophene carbaldehydes (methyl‐ or ethyl‐substituted) and applied to the catalytic asymmetric Henry reaction of various aldehydes with nitromethane to provide β‐hydroxy nitroalkanols in high conversion (92%). The reaction was optimized in terms of the metal, solvent, temperature and amount of chiral ligand. The corresponding catalyst with Cu(OTf)2 and 2‐propanol as the solvent provided the best enantioselectivities (up to 96% ee) of the corresponding nitroalcohols for aliphatic aldehydes. Copyright © 2013 John Wiley & Sons, Ltd.
Sequence length determinants for self‐assembly of amphipathic β‐sheet peptides
Authors: Lee Naomi R. , Bowerman Charles J. , Nilsson Bradley L.
Published: March 2013

Amphipathic peptides composed of alternating hydrophobic and hydrophilic amino acids are a privileged class of peptide, which have a high propensity to self‐assemble into β‐sheet fibrils. The Ac‐(FKFE)2‐NH2 peptide has been extensively studied and forms putative β‐sheet bilayer fibrils in which the hydrophobic Phe side chains are organized to a single face of each constituent sheet; upon bilayer formation, these hydrophobic benzyl groups are sequestered in the hydrophobic core of the resulting fibril. In order for the Phe side chains to be uniformly displayed on one face of Ac‐(FKFE)2‐NH2 β‐sheets, an antiparallel packing orientation in which one amino acid residue is unpaired must be adopted. Based on molecular models, we hypothesized that truncated seven amino acid derivatives of Ac‐(FKFE)2‐NH2 in which either the N‐terminal Phe residue (Ac‐KFEFKFE‐NH2) or the C‐terminal Glu residue (Ac‐FKFEFKF‐NH2) is eliminated should readily self‐assemble into β‐sheet bilayers in which all hydrogen bond and hydrophobic/charge interactions are satisfied. We found, however, that these minute changes in peptide sequence have unanticipated and dramatic effects on the self‐assembly of each peptide. Ac‐FKFEFKF‐NH2 self‐assembled into fibrils with unique morphology relative to the parent peptide, whereas the Ac‐KFEFKFE‐NH2 peptide had a strongly reduced propensity to self‐assemble, even failing to self‐assemble altogether under some conditions. These findings provide significant insight into the effect of sequence length and strand registry as well as hydrophobicity and charge on the self‐assembly of simple amphipathic peptides to illuminate the possibility of tuning self‐assembly processes and the resulting structures with minute changes to peptide sequence. © 2013 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 100: 738–750, 2013.
Sexually dimorphic expression and estradiol mediated up‐regulation of a sex‐linked ribosomal gene, RPS6, in the zebra finch brain
Authors: Acharya Kalpana D. , Veney Sean L.
Published: March 2013

Sex‐linked genes are considered to be a major contributor to neural sex differences in zebra finches. While several candidates have been identified, additional ones are continuously being discovered. Here we report on a novel Z‐linked ribosomal gene (rpS6) that is enhanced in the male brain as compared to the female's throughout life. In both sexes, expression of rpS6 is highest at P3 and P8 (just before the onset of morphologically detectable sex differences), decreases around P15, and then remains decreased through adulthood. Analysis of rpS6 mRNA revealed widespread distribution throughout the brain. However, within song regions HVC and RA, mRNA containing cells were greater in males as compared to females. Hormones are also involved in the development of neural dimorphisms, so we additionally investigated whether rpS6 might interact with estradiol (E2). An up‐regulation of rpS6 gene was observed in both sexes following treatment with E2 and the effect was approximately twice as large in males as compared with females. These data suggest that rpS6 may be involved in sexual differentiation of the zebra finch brain, and that the effect is facilitated by E2. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 599–608, 2013
A canonical response of precipitation characteristics to global warming from CMIP5 models
Authors: Lau William K.‐M. , Wu H.‐T. , Kim K.‐M.
Published: March 2013

In this study, we find from analyses of projections of 14 CMIP5 models a robust, canonical global response in rainfall characteristics to a warming climate. Under a scenario of 1% increase per year of CO2 emission, the model ensemble projects globally more heavy precipitation (+7 ± 2.4%K−1), less moderate precipitation (−2.5 ± 0.6%K−1), more light precipitation (+1.8 ± 1.3%K−1), and increased length of dry (no‐rain) periods (+4.7 ± 2.1%K−1). Regionally, a majority of the models project a consistent response with more heavy precipitation over climatologically wet regions of the deep tropics, especially the equatorial Pacific Ocean and the Asian monsoon regions, and more dry periods over the land areas of the subtropics and the tropical marginal convective zones. Our results suggest that increased CO2 emissions induce a global adjustment in circulation and moisture availability manifested in basic changes in global precipitation characteristics, including increasing risks of severe floods and droughts in preferred geographic locations worldwide.
The plumbing of Old Faithful Geyser revealed by hydrothermal tremor
Authors: Vandemeulebrouck J. , Roux P. , Cros E.
Published: March 2013

Old Faithful Geyser in Yellowstone National Park (USA) has attracted numerous scientific investigations for over two centuries to better understand its geological structure, the physics of its eruptions, and the controls of its intermittency. Using data acquired with a seismic array in 1992, we track the sources of hydrothermal tremor produced by boiling and cavitation inside the geyser. The location of seismic sources identifies a previously unknown lateral cavity at 15 m below the surface, on the SW side of the vent, and connected to the conduit. This reservoir is activated at the beginning of each geyser eruption cycle and plays a major role in the oscillatory behavior of the water level in the conduit before each eruption.
A connection to deep groundwater alters ecosystem carbon fluxes and budgets: Example from a Costa Rican rainforest
Authors: Genereux David P. , Nagy Laura A. , Osburn Christopher L. , Oberbauer Steven F.
Published: March 2013

Field studies of watershed carbon fluxes and budgets are critical for understanding the carbon cycle, but the role of deep regional groundwater is poorly known and field examples are lacking. Here we show that discharge of regional groundwater into a lowland Costa Rican rainforest has a major influence on ecosystem carbon fluxes. This influence is observable through chemical, isotopic, and flux signals in groundwater, surface water, and air. Not addressing the influence of regional groundwater in the field measurement program and data analysis would give a misleading impression of the overall carbon source or sink status of the rainforest. In quantifying a carbon budget with the traditional “small watershed” mass balance approach, it would be critical at this site and likely many others to consider watershed inputs or losses associated with exchange between the ecosystem and the deeper hydrogeological system on which it sits.
Regional patterns and proximal causes of the recent snowpack decline in the Rocky Mountains, U.S.
Authors: Pederson Gregory T. , Betancourt Julio L. , McCabe Gregory J.
Published: March 2013

We used a first‐order, monthly snow model and observations to disentangle seasonal influences on 20th century,regional snowpack anomalies in the Rocky Mountains of western North America, where interannual variations in cool‐season (November–March) temperatures are broadly synchronous, but precipitation is typically antiphased north to south and uncorrelated with temperature. Over the previous eight centuries, regional snowpack variability exhibits strong, decadally persistent north‐south (N‐S) antiphasing of snowpack anomalies. Contrary to the normal regional antiphasing, two intervals of spatially synchronized snow deficits were identified. Snow deficits shown during the 1930s were synchronized north‐south by low cool‐season precipitation, with spring warming (February–March) since the 1980s driving the majority of the recent synchronous snow declines, especially across the low to middle elevations. Spring warming strongly influenced low snowpacks in the north after 1958, but not in the south until after 1980. The post‐1980, synchronous snow decline reduced snow cover at low to middle elevations by ~20% and partly explains earlier and reduced streamflow and both longer and more active fire seasons. Climatologies of Rocky Mountain snowpack are shown to be seasonally and regionally complex, with Pacific decadal variability positively reinforcing the anthropogenic warming trend.
Hydroclimatic changes and analysis of floods in large river basins of southern East Siberia
Authors: Kichigina N.
Published: March 2013

Flood risk in Siberia increased in recent years. This is most often associated with two main reasons: global climate change, and the increase in economic development in territories at risk of flooding and resulting human impacts on river basins. We tried to bring new data and results on this topic. The objective of this paper is to assess the change in the hydrological regime under climatic changes and the dynamics of flood recurrence on the river basins of southern East Siberia in the latter half of the 20th and the beginning of the 21st century. We used information on run‐off and water levels obtained from hydrological stations of the Irkutsk and Ulan‐Ude Administration for Hydrometeorology and Environmental Monitoring.

The annual and monthly mean run‐off data series were subjected to statistical analysis. Linear trends and their significance were evaluated in general for the identical period from 1961 to 2006 at 37 gauging stations. Flood recurrence in the Angara and Lena river basins was calculated for two periods – before the expressed climatic changes (1960–1979) and for the expressed climatic changes (1980–2005). In general, the value of the annual run‐off was unchanged. The intra‐annual redistribution of run‐off occurs, showing a reduction in the run‐off from spring snowmelt and an increase in run‐off for the autumn – winter low water period. Intra‐annual run‐off redistribution under climatic changes does not provoke an increase in extreme conditions. The analysis of flood recurrences showed no significant changes in the mean recurrence in basins. However, there was either a significant increase or decrease in the number of floods for some gauging stations. Remote sensing data were used to analyse the dynamics of human impact on such river basins. Copyright © 2013 John Wiley & Sons, Ltd.
Molecular characterization of anastrozole resistance in breast cancer: Pivotal role of the Akt/mTOR pathway in the emergence of de novo or acquired resistance and importance of combining the allosteric Akt inhibitor MK‐2206 with an aromatase inhibitor
Authors: Vilquin Paul , Villedieu Marie , Grisard Evelyne , Larbi Sabrina Ben , Ghayad Sandra E. , Heudel Pierre‐Etienne , Bachelot Thomas , Corbo Laura , Treilleux Isabelle , Vendrell Julie A. , Cohen Pascale A.
Published: March 2013

Acquisition of resistance to aromatase inhibitors (AIs) remains a major drawback in the treatment of estrogen receptor alpha (ERα)‐positive breast cancers. The Res‐Ana cells, a new model of acquired resistance to anastrozole, were established by long‐term exposure of aromatase‐overexpressing MCF‐7 cells to this drug. These resistant cells developed ER‐independent mechanisms of resistance and decreased sensitivity to the AI letrozole or to ERα antagonists. They also displayed a constitutive activation of the PI3K/Akt/mTOR pathway and a deregulated expression of several ErbB receptors. An observed increase in the phospho‐Akt/Akt ratio between primary and matched recurrent breast tumors of patients who relapsed under anastrozole adjuvant therapy also argued for a pivotal role of the Akt pathway in acquired resistance to anastrozole. Ectopic overexpression of constitutively active Akt1 in control cells was sufficient to induce de novo resistance to anastrozole. Strikingly, combining anastrozole with the highly selective and allosteric Akt inhibitor MK‐2206 or with the mTOR inhibitor rapamycin increased sensitivity to this AI in the control cells and was sufficient to overcome resistance and restore sensitivity to endocrine therapy in the resistant cells. Our findings lead to us proposing a model of anastrozole‐acquired resistance based on the selection of cancer‐initiating‐like cells possessing self‐renewing properties, intrinsic resistance to anastrozole and sensitivity to MK‐2206. Altogether, our work demonstrated that the Akt/mTOR pathway plays a key role in resistance to anastrozole and that combining anastrozole with Akt/mTOR pathway inhibitors represents a promising strategy in the clinical management of hormone‐dependent breast cancer patients.
BRAF V600E‐specific immunohistochemistry for the exclusion of Lynch syndrome in MSI‐H colorectal cancer
Authors: Capper David , Voigt Anita , Bozukova Gergana , Ahadova Aysel , Kickingereder Philipp , von Deimling Andreas , von Knebel Doeberitz Magnus , Kloor Matthias
Published: March 2013

The differentiation between hereditary and sporadic microsatellite‐unstable (MSI‐H) colorectal cancer is a crucial step in Lynch syndrome diagnostics. Within MSI‐H colorectal cancers, the BRAF V600E mutation is strongly associated with sporadic origin. Here, we asked whether BRAF V600E‐specific immunohistochemistry (clone VE1) is helpful in separating sporadic from Lynch syndrome‐associated MSI‐H colorectal cancers. To that end, we performed VE1 immunohistochemistry and BRAF sequencing in a series of 91 MSI‐H colorectal cancer specimens from patients tested for Lynch syndrome. Concordance of VE1 immunohistochemistry and molecular BRAF mutation status was observed in 90 of 91 (98.9%) MSI‐H samples. All 11 tumors classified as BRAF V600E mutation‐positive by Sanger sequencing were immunopositive, and 79 (98.8%) of 80 tumors classified as BRAF wild type showed negative staining. All VE1‐positive tumors were MLH1‐ and PMS2‐negative by immunohistochemistry. None of the tumors from mismatch repair (MMR) gene germline mutation carriers (n = 28) displayed positive VE1 staining, indicating that BRAF V600E mutation‐specific immunostaining has a low risk of excluding Lynch syndrome patients from germline mutation analysis. In conclusion, implementation of VE1 immunohistochemistry was able to detect BRAF‐mutated MSI‐H colorectal cancers with a sensitivity of 100% and a specificity of 98.8%. Among MLH1‐negative colorectal cancers, the rate of VE1‐positive lesions was 21%, offering the exclusion of these patients from MMR germline testing. Therefore, we suggest the integration of VE1 immunohistochemistry into the diagnostic panel of Lynch syndrome.
Body mass index, lifetime smoking intensity and lung cancer risk
Authors: El‐Zein Mariam , Parent Marie‐Elise , Nicolau Belinda , Koushik Anita , Siemiatycki Jack , Rousseau Marie‐Claude
Published: March 2013

There is as yet no generally accepted explanation for the common finding that low body mass index (BMI) is associated with an increased risk of lung cancer. We investigated this association in a Canadian population‐based case–control study (1996–2002) with a particular view to assessing the hypothesis that the observed association was due to residual confounding by smoking. Analyses were based on 1,076 cases and 1,439 controls who provided their height at enrollment and their weight at two points in time, at age 20 and 2 years before enrollment. BMI, in kg/m2, was classified into underweight (<18.5), normal (18.5–24.9), overweight (25.0–29.9), and obese (≥30). Smoking history was synthesized into a comprehensive smoking index (CSI) that integrated duration, intensity and time since quitting. Odds ratios (ORs) and 95% confidence intervals (CIs) for BMI‐lung cancer associations were estimated, adjusting for CSI as well as several sociodemographic, lifestyle and occupational factors. The normal BMI category was used as the reference. Among those who were underweight at age 20, there was a lower risk of lung cancer (OR = 0.69, 95% CI: 0.50–0.95). Conversely, lung cancer risk was increased among those who were underweight 2 years before enrollment (OR = 2.30, 95% CI: 1.30–4.10). The results were almost identical when stratifying analyses based on smoking history into never/lighter and heavier smokers. The inverse association between recent BMI and lung cancer is unlikely to be largely attributable to residual confounding by smoking. Reverse causality or a true relationship between BMI and lung cancer remain plausible.
Winner for outstanding research in the Ph.D. category for the 2013 society for biomaterials meeting and exposition, April 10–13, 2013, Boston, Massachusetts
Authors: Rao Rameshwar R. , Peterson Alexis W. , Stegemann Jan P.
Published: March 2013

Modular tissue engineering applies biomaterials‐based approaches to create discrete cell‐seeded microenvironments, which can be further assembled into larger constructs for the repair of injured tissues. In the current study, we embedded human bone marrow‐derived mesenchymal stem cells (MSC) and human adipose‐derived stem cells (ASC) in collagen/fibrin (COL/FIB) and collagen/fibrin/hydroxyapatite (COL/FIB/HA) microbeads, and evaluated their suitability for bone tissue engineering applications. Microbeads were fabricated using a water‐in‐oil emulsification process, resulting in an average microbead diameter of approximately 130 ± 25 μm. Microbeads supported both cell viability and cell spreading of MSC and ASC over 7 days in culture. The embedded cells also began to remodel and compact the microbead matrix as demonstrated by confocal reflectance microscopy imaging. After two weeks of culture in media containing osteogenic supplements, both MSC and ASC deposited calcium mineral in COL/FIB microbeads, but not in COL/FIB/HA microbeads. There were no significant differences between MSC and ASC in any of the assays examined, suggesting that either cell type may be an appropriate cell source for orthopedic applications. This study has implications in the creation of defined microenvironments for bone repair, and in developing a modular approach for delivery of pre‐differentiated cells. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Characterization of bone mineral‐resembling biomaterials for optimizing human osteoclast differentiation and resorption
Authors: Nakamura Miho , Hentunen Teuvo , Salonen Jukka , Nagai Akiko , Yamashita Kimihiro
Published: March 2013

Bioresorption is a biological mechanism by which biomaterials are resorbed and thereby disappear from implantation sites partially or completely over a period of time. Osteoclast‐medicated bioresorption is a possible new advantage to incorporate material degradation into remodeling in bone metabolism process. The purpose of this study was to investigate the osteoclastogenesis and bioresorption of synthesized calcium phosphate materials. Differentiation into mature human osteoclasts on carbonated hydroxyapatite (CA) was significantly enhanced compared to hydroxyapatite (HA) and β‐tricalcium phosphate, based on the quantitative gene expressions of molecular markers for osteoclast differentiation. Osteoclasts adhered and differentiated into giant multinuclear TRAP‐positive cells on every type of synthesized sample based on the histological analysis. Morphological observations using fluorescence and quantitative analysis revealed that the actin rings of osteoclasts on CA were thick, small in diameter and co‐localized with vinculin, similar to the rings found on bone slices. In contrast, the actin rings of osteoclasts on HA and culture dishes were thin and large in diameter. Scanning electron microscopic images and quantitative analysis indicated that the resorption pits on CA were significantly deeper than those on HA due to the enhanced tight sealing ability between osteoclasts and their substrate. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3141–3151, 2013.
Mechanical properties of decellularized tendon cultured by cyclic straining bioreactor
Authors: Lee Kwang‐Il , Lee Jung‐Soo , Kim Jin‐Gu , Kang Kyoung‐Tak , Jang Ju‐Woong , Shim Young‐Bock , Moon Seong‐Hwan
Published: March 2013

Decellularized tissues have been successfully used in tissue engineering and regenerative medicine for the purpose of removing antigens present in the cellular components. However, this decellularization technique uses ionic solutions or chemical treatments such as enzyme treatments that might damage the biophysical properties or reduce the physical strength of tissue. This study aimed to improve the strength of decellularized tissues. We designed a tissue bioreactor that can repeatedly deliver physical stimulation, such as tensile and torsional deformation, to the upper and lower parts of a tissue. To decellularized porcine Tibialis tendons, we used an enzymatic solution to remove the primary cells, and then applied ultrasonic cleansing using a combination of ionic solution and distilled water to destroy residual cells by differing from the osmotic pressure between the inside and outside of the cell membrane. The total DNA content of decellularized tissue was decreased by 77% compared with that of the original tissue and the ultimate tensile strength of the decellularized tissue was 20% lower than that of the normal tissue. Decellularized tissues were then cultivated in the tissue bioreactor with repeated physical stimulation of 110% tension, 90° torsion, and frequency of once per a second, and the ultimate tensile strength was found to be greater than that of the normal ligament at 7 day culture. This study showed that decellularization using enzyme and mechanical treatment is safe and use of a tissue bioreactor can increase the physical strength of tendons, making this a potential mechanism to reconstruct human ligaments. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3152–3158, 2013.
Fabrication of a 3D hair follicle‐like hydrogel by soft lithography
Authors: Pan Jing , Yung Chan Sui , Common John E. A. , Amini Shahrouz , Miserez Ali , Birgitte Lane E. , Kang Lifeng
Published: March 2013

Hair follicle transplantation is often used in the treatment of androgenetic alopecia (AGA). However, the only source of hair follicles is from human donors themselves, which limits the application of this approach. One possible solution is to reconstitute hair follicle from dissociated cells. Currently, a number of microscale technologies have been developed to create size and shape controlled microenvironments in tissue engineering. Photopolymerizable PEGDA hydrogels are often selected as promising scaffolds in engineered microtissues due to their biocompatibility and adjustable mechanical properties. Here, we fabricated an array of PEGDA microwells with center islets that mimic the architecture of human hair follicles using soft lithography. Dermal and epithelial cells were seeded in different compartments of the microstructured mould to mimic mesenchymal and epithelial compartmentalization in native hair follicles. We demonstrated that these compartmentalized microstructures support cell proliferation and cell survival over 14 days, and spreading of dermal fibroblasts was observed. This hydrogel micromould provides a potentially useful tool for engineering 3D hair follicle‐mimicking complex culturesin vitro. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 3159–3169, 2013.
Aerosol Particle Size Does Not Predict Pharmacokinetic Determined Lung Dose in Children
Authors: Bønnelykke Klaus , Chawes Bo L. K. , Vindfeld Signe , Moore Alison C. , Bisgaard Hans
Published: March 2013

In vitro measures of aerosol particles size, such as the fine particle mass, play a pivotal role for approval of inhaled anti‐asthmatic drugs. However, the validity as a measure of dose to the lungs in children lacks evidence. In this study we investigated for the first time the association between an in vivo estimate of lung dose of inhaled drug in children and the corresponding particle size segments assessed ex vivo. Lung dose of fluticasone propionate after inhalation from a dry powder inhaler (Diskus®) was studied in 23 children aged 4–7 and 12–15 years with mild asthma. Six‐hour pharmacokinetics was assessed after single inhalation. The corresponding emitted mass of drug in segments of aerosol particle size was assessed ex vivo by replicating the inhalation flows recorded by transducers built into the Diskus® inhaler and re‐playing them in a breathing simulator. There was no correlation between any inhaled particle size segment and lung dose assessed by pharmacokinetics and adjusted for age and body size. Measures of particles size segments were not related to lung dose in children. Until further evidence is provided it may be warranted to emphasize pharmacokinetic or pharmacodynamic assessments of drug delivery to the lung.
Impact of Sildenafil on Survival of Patients With Eisenmenger Syndrome
Authors: Sun Yun‐Juan , Yang Tao , Zeng Wei‐Jie , Gu Qing , Ni Xin‐Hai , Zhao Zhi‐Hui , Liu Zhi‐Hong , Xiong Chang‐Ming , He Jian‐Guo
Published: March 2013

The favorable effects of short‐term use of sildenafil on patients with Eisenmenger syndrome have been reported. We further studied the impact of long‐term use of sildenafil on survival of these patients. In this study, the baseline data of patients newly diagnosed as Eisenmenger syndrome in our hospital between January 2005 and December 2009 were retrospectively collected. Patients were followed‐up either by telephone contacts or during visits in our out‐patient clinic. A total of 121 patients (68 patients in conventional group and 53 patients in sildenafil group) were finally included and 29 patients were re‐evaluated after sildenafil therapy for 3–4 months. Compared with the baseline, a 6‐minute walk distance, functional classes, plasma hemoglobin level, and hemodynamics were significantly improved after sildenafil treatment. During a median follow‐up period of 35.8 months, 15 patients died (11 patients in conventional group). The 1‐ and 3‐year survival rates in sildenafil group were 97.0% and 95.2%, significantly higher than 90.6% and 82.9% in conventional group P = .025). Multivariate analysis showed that sildenafil therapy, functional class and mean pulmonary arterial pressure were independently associated with survival. Therefore, long‐term sildenafil therapy improved survival in patients with Eisenmenger syndrome.
Removal of 2,4‐dichlorophenol by aluminium/O2/acid system
Authors: Lin Kunde , Cai Jianjun , Sun Jianqiang , Xue Xiuling
Published: March 2013

Background

Although the oxidative removal of organic compounds by the Al/O2/acid system has been previously studied, the in situ generation of reactive oxygen species (ROS) and its influencing factors are not well understood. 2,4‐dichlorophenol (2,4‐DCP) is one of the priority control pollutants and widely present in the environment. In this study, the oxidative removal of 2,4‐DCP by the Al/O2/acid system was investigated, especially the in situ generation of ROS and influencing factors.

Results

More than 90% of 2,4‐DCP was removed within 10 h in pH 2.5 solutions initially containing 10 g L−1 Al and 8.25 mg L−1 dissolved oxygen. The removal of 2,4‐DCP was acid and oxygen driven and was accompanied by the release of chloride ions. While the reduction of oxygen to H2O2 by Al was obtained only under conditions of pH < 4.0, the subsequent Al‐mediated transformation of H2O2 to •OH was achieved under pH < 5.0 conditions. Furthermore, five primary intermediates were identified and oxidation pathways of 2,4‐DCP by the Al/O2/acid system were proposed.

Conclusions

This work describes a potential method for the removal of 2,4‐DCP in aqueous environments. Oxygen levels and solution pH played important roles in the removal of 2,4‐DCP by Al/O2/acid system. © 2013 Society of Chemical Industry
Removal of nickel from aqueous solution using cathodic deposition of nickel hydroxide at a modified electrode
Authors: Liu YaoXing , Wu XiaoYun , Yuan DongXing , Yan JunMei
Published: March 2013

Background

In the present study, an electrochemical technique was used to remove nickel from aqueous solutions on a laboratory scale using a self‐made Plexiglas cell. Electrodes comprising a stainless steel net coated with single‐walled carbon nanotubes (SWCNTs@SSN) were used as both the anode and the cathode. The effects of various parameters on the percentage of nickel removed were investigated, including the solution pH, applied voltage, electrolyte concentration, and the amount of SWCNTs coated on the electrodes.

Results

The optimal parameters were found to be pH 10.0, applied voltage 2.5 V, and electrolyte concentration 10 g dm‐3. Under optimal conditions, 95.1% of the nickel present in nickel‐contaminated factory wastewater was removed. The mechanism of nickel removal was also investigated. X‐ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) analyses showed that the nickel ions were being removed in the form of Ni(OH)2, which was deposited on the cathode. The SWCNTs@SSN electrodes were regenerated easily.

Conclusion

The results of the study proved that the method is a potential technique for the treatment of industrial wastewater containing heavy‐metal ions. © 2013 Society of Chemical Industry
Hybrid vapor stripping–vapor permeation process for recovery and dehydration of 1‐butanol and acetone/butanol/ethanol from dilute aqueous solutions. Part 1. Process Simulations
Authors: Vane Leland M. , Alvarez Franklin R.
Published: March 2013

Background

Fermentative production of butanol is limited to low concentrations, typically less than 2 wt% solvent, due to product inhibition. The result is high separation energy demand by conventional distillation approaches, despite favorable vapor–liquid equilibrium and partial miscibility with water. In previous work, a process integrating steam stripping, vapor compression, and vapor permeation separation was proposed for separating ethanol from water. Such a membrane assisted vapor stripping (MAVS) process is considered in this work for 1‐butanol/water and acetone/butanol/ethanol/water (ABE/water) separation.

Results

Using process simulations, the earlier MAVS design was estimated to require 6.2 MJ‐fuel kg−1‐butanol to produce 99.5 wt% 1‐butanol from a 1 wt% 1‐butanol feed, representing an energy savings of 63% relative to a benchmark distillation/decanter system. Adding a fractional condensation step to the original MAVS design is predicted to reduce energy demand to only 4.8 MJ‐fuel kg−1‐butanol and reduce membrane area by 65%.

Conclusion

In the hybrid distillation/membrane MAVS systems, the stripping column provides high butanol recovery and low effluent concentration while the vapor compression and membrane steps enable the efficient recovery of latent and sensible heat from both the retentate and permeate streams from the membrane system. Addition of the dephlegmator condenser reduces both compressor size and membrane area. Published 2013. This article is a U.S. Government work and is in the public domain in the USA
Removal of tributyltin from shipyard process wastewater by fly ash, activated carbon and fly ash/activated carbon composite: adsorption models and kinetics
Authors: Ayanda Olushola S. , Fatoki Olalekan S. , Adekola Folahan A. , Ximba Bhekumusa J.
Published: March 2013

Background

The removal of tributyltin (TBT) from shipyard process wastewater using fly ash, activated carbon and fly ash/activated carbon composite was investigated.

Results

Adsorption experiments performed on TBT‐contaminated artificial process wastewater revealed that the adsorption capacity of TBT increases with increase in the adsorbent amount, contact time, pH, stirring speed and initial TBT concentration. The adsorption isotherms and the kinetic data were well described by the Freundlich and pseudo‐second‐order kinetic model, respectively. The negative values of the Gibbs energy change (ΔGo) indicated the spontaneous nature of the adsorption and the positive values of the enthalpy change (ΔHo) showed that the adsorption process is endothermic. Optimal conditions for the adsorption of TBT from contaminated artificial process wastewater were applied to TBT removal from natural shipyard process wastewater and the results showed that 94.2%, 99.2% and 99.8% TBT were removed by the fly ash, activated carbon and fly ash/activated carbon composite, respectively.

Conclusion

This study showed that the precursors as well as the composite could be employed as efficient adsorbents for the removal of TBT from contaminated shipyard process wastewater with the composite material exhibiting the highest adsorption efficiency. © 2013 Society of Chemical Industry
MRT letter: Visual attention driven framework for hysteroscopy video abstraction
Authors: Ejaz Naveed , Mehmood Irfan , Baik Sung Wook
Published: March 2013

Diagnostic hysteroscopy is a popular method for investigating the regions in the female reproductive system. The videos generated by hysteroscopy sessions of patients are recurrently archived in medical libraries. Gynecologists often need to browse these libraries in search of similar cases or for reviewing old videos of a patient. Diagnostic hysteroscopy videos contain a lot of information with abundant redundancy. Key frame extraction‐based video summarization can be used to reduce this huge amount of data. Moreover, key frames can be used for browsing and indexing of hysteroscopy videos. In this article, a domain specific visual attention driven framework for summarization of hysteroscopy videos is proposed. The visual attention model is materialized by computing saliency based on color, texture, and motion. The experimental results, in comparison with other techniques, demonstrate the efficacy of the proposed framework. Microsc. Res. Tech. 76:559–563, 2013. © 2013 Wiley Periodicals, Inc.
A method for structure analysis of nanomaterials by electron diffraction: Phase identification and unit cell determination
Authors: Honglong Shi , Guling Zhang , Bin Zou , Minting Luo , Wenzhong Wang
Published: March 2013

We report a quick and easy method for a random selected area electron diffraction (SAED) pattern without rotating and tilting the specimen to perform phase identification and unit cell determination by combined with the XRD softwares. If your TEM is well aligned and camera length is carefully corrected, two‐dimensional (2D)‐SAED pattern can be directly transformed to 1D‐profile after the center determination of pattern, this profile is then imported to XRD analysis packages. Finally, phase identification and unit cell determination can be performed after peak search or precise peak position determined by profile fitting. Two examples, flaky‐like TiO2 nanomaterial and TiO2 nanotubes precipitated by the silver nanoparticles, were tested and verified for the validation of phase identification and unit cell determination using this method; the successful crystallographic analysis of one single gold nanocrystal indicates it is still validate for the nanocrystals with the smaller diffraction volume, but need two or more random tilt SAED patterns. This method could be further used in the quantitative phase analysis, structure determination and Rietveld refinement for the nanomaterials if the reliable integrated intensity can be extracted. Microsc. Res. Tech. 76:641–647, 2013. © 2013 Wiley Periodicals, Inc.
Portal vein arterialization using an accessory right hepatic artery in liver transplantation
Authors: Paloyo Siegfredo , Nishida Seigo , Fan Ji , Tekin Akin , Selvaggi Gennaro , Levi David , Tzakis Andreas
Published: March 2013

Portal vein thrombosis remains to be a challenging issue during liver transplantation even with the acquisition of innovative surgical techniques and years of experience. Most frequently, an initial eversion thromboendovenectomy is performed and depending on the extent of thrombosis and intraoperative findings, further revascularization options include venous jump grafts, portocaval hemitransposition, renoportal anastomosis or portal vein arterialization. Reports on these surgical approaches are limited although with acceptable outcomes. We present a 64-year-old patient with hepatitis C cirrhosis who underwent orthotopic liver transplantation with portal vein arterialization using an accessory right hepatic artery. Liver graft function has remained stable four years after transplant with notable aneurysmal dilatation of the portal vein. Liver Transpl 19:773–775, 2013. © 2013 AASLD.
Deterministic chaos in frictional wedges revealed by convergence analysis
Authors: Mary B.C.L. , Maillot B. , Leroy Y.M.
Published: March 2013

A triangular wedge, composed of a frictional material such as sand, and accreting additional material at its front, is the classical prototype for accretionary wedges and fold‐and‐thrust belts. A simplified method is proposed to capture the internal deformation of this structure resulting from a large number of faulting events during compression. The method combines the application of the kinematic approach of limit analysis to predict the optimum thrust‐fold and a set of geometrical rules to update the geometry accordingly, at each increment of shortening. It is shown that the structure topography remains approximately planar with a slope predicted by the critical Coulomb wedge theory. Failure by faulting occurs anywhere within the wedge at criticality, and its exact position is sensitive to topographic perturbations resulting from the deformation history. The convergence analysis in terms of the shortening increments and of the topography discretization reveals that the timing and the position of a single faulting event cannot be predicted. The convergence is achieved nevertheless in terms of the statistics of the distribution of the faulting events throughout the structure and during the entire deformation history. It is these two convergence properties that are presented to justify the claim that these compressed frictional wedges are imperfection sensitive, chaotic systems. Copyright © 2013 John Wiley & Sons, Ltd.
Numerical determination of the tensile response and the dissipated fracture energy of concrete: role of the mesostructure and influence of the loading rate
Authors: Gatuingt F. , Snozzi L. , Molinari J. F.
Published: March 2013

At the mesoscopic scale, concrete can be considered as a mix of coarse aggregates with a mortar paste matrix. In this paper, we investigate numerically the influence of aggregates arrangements and loading rate on the tensile response of concrete. Each coarse aggregate is assumed to be circular with six different radiuses following the aggregates size distribution of real gravel. Rate‐independent cohesive elements are used to model failure within the mesostructure. Our results show that the spatial distribution of heterogeneities does not influence the peak strength, while it changes the post‐peak macroscopic response. This implies that our specimen size is large enough for strength computation but that larger mesostructures should be considered to obtain fully reliable toughness predictions. Although the cohesive approach is able to capture the transition from one macro‐crack in quasi‐static to multiple micro‐cracks in fast dynamics, which increases the dissipated fracture energy, our results suggest that the full extent of the high‐rate strengthening of concrete observed experimentally for loading rates greater than 1/s cannot be captured with rate independent constitutive laws.Copyright © 2013 John Wiley & Sons, Ltd.