bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of prenyllipids in the chloroplasts of the liverwort Heteroscyphus planus
Authors: Karunagoda RP
Published: April 2011

Liverworts belonging to the Class Hepaticae of the Division Bryophyta, are an excellent source of lower terpenoids. They possess intracellular oil bodies which are composed of lipophilic terpenoids and aromatic compounds. In this study, an attempt was made to identify the prenyllipid component that is localized to the chloroplasts of the liverwort, Heteroscyphus planus (Mitt.) Shiffner. The prenyl diphosphates were extracted by stirring the intact chloroplasts overnight in methanol, without rupturing the chloroplasts in liquid nitrogen. The chloroplasts were found to contain farnesyl diphosphate and geranylgranyl diphosphate which were detected after hydrolysis by alkaline phosphatase to their respective isoprenols, farnesol and geranylgeraniol. Hydrolysis with KOH yielded phytol and geranylgeraniol which were present in the chloroplasts as esters with chlorophyllide (chlorophyll a and geranylgranyl diphosphate-chlorophyllide respectively). Only phytol was detected at high level, whereas, geranylgranyl diphosphate and geranylgranyl diphosphate-ester were at very low levels. The cis and trans isomers of farnesol were separately identified, but in very low quantities. These results were further confirmed by GC-MS analysis. Linoleic acid, palmitic acid, methyl ester of palmitic acid and the ester of phthalate acid were identified as other lipids localized to the chloroplasts of H. planus. Keywords: terpenoids; lipophilic; farnesol; geranylgeraniol; phytol DOI: 10.4038/cjsbs.v39i2.2998 Cey. J. Sci. (Bio. Sci.) 39 (2): 121-127, 2010
Increased Th2 Cytokine Secretion, Eosinophilic Airway Inflammation, and Airway Hyperresponsiveness in Neurturin-Deficient Mice
Authors: Michel Tatiana , Thérésine Maud , Poli Aurélie , Domingues Olivia , Ammerlaan Wim , Brons Nicolaas H. C. , Hentges François , Zimmer Jacques
Published: April 2011

Neurotrophins such as nerve growth factor and brain-derived neurotrophic factor have been described to be involved in the pathogenesis of asthma. Neurturin (NTN), another neurotrophin from the glial cell line-derived neurotrophic factor family, was shown to be produced by human immune cells: monocytes, B cells, and T cells. Furthermore, it was previously described that the secretion of inflammatory cytokines was dramatically stimulated in NTN knockout (NTN−/−) mice. NTN is structurally similar to TGF-β, a protective cytokine in airway inflammation. This study investigates the implication of NTN in a model of allergic airway inflammation using NTN−/− mice. The bronchial inflammatory response of OVA-sensitized NTN−/− mice was compared with wild-type mice. Airway inflammation, Th2 cytokines, and airway hyperresponsiveness (AHR) were examined. NTN−/− mice showed an increase of OVA-specific serum IgE and a pronounced worsening of inflammatory features. Eosinophil number and IL-4 and IL-5 concentration in the bronchoalveolar lavage fluid and lung tissue were increased. In parallel, Th2 cytokine secretion of lung draining lymph node cells was also augmented when stimulated by OVA in vitro. Furthermore, AHR was markedly enhanced in NTN−/− mice after sensitization and challenge when compared with wild-type mice. Administration of NTN before challenge with OVA partially rescues the phenotype of NTN−/− mice. These findings provide evidence for a dampening role of NTN on allergic inflammation and AHR in a murine model of asthma.
MAL Protein Controls Protein Sorting at the Supramolecular Activation Cluster of Human T Lymphocytes
Authors: Antón Olga M. , Andrés-Delgado Laura , Reglero-Real Natalia , Batista Alicia , Alonso Miguel A.
Published: April 2011

T cell membrane receptors and signaling molecules assemble at the immunological synapse (IS) in a supramolecular activation cluster (SMAC), organized into two differentiated subdomains: the central SMAC (cSMAC), with the TCR, Lck, and linker for activation of T cells (LAT), and the peripheral SMAC (pSMAC), with adhesion molecules. The mechanism of protein sorting to the SMAC subdomains is still unknown. MAL forms part of the machinery for protein targeting to the plasma membrane by specialized mechanisms involving condensed membranes or rafts. In this article, we report our investigation of the dynamics of MAL during the formation of the IS and its role in SMAC assembly in the Jurkat T cell line and human primary T cells. We observed that under normal conditions, a pool of MAL rapidly accumulates at the cSMAC, where it colocalized with condensed membranes, as visualized with the membrane fluorescent probe Laurdan. Mislocalization of MAL to the pSMAC greatly reduced membrane condensation at the cSMAC and redistributed machinery involved in docking microtubules or transport vesicles from the cSMAC to the pSMAC. As a consequence of these alterations, the raft-associated molecules Lck and LAT, but not the TCR, were missorted to the pSMAC. MAL, therefore, regulates membrane order and the distribution of microtubule and transport vesicle docking machinery at the IS and, by doing so, ensures correct protein sorting of Lck and LAT to the cSMAC.
Asklepios: Sy rol in die evolusie van die Geneeskunde
Authors: Retief François P. , Cilliers Louise
Published: April 2011

Asclepius is first mentioned by Homer as leader and physician in the Trojan War. Later, during the 5th century, he became known as the god of healing, and in this century the Asclepian cult of healing became established in Epidaurus. This healing cult, which was accommodated by empiric (Hippocratic) physicians of the time, endured for close on ten centuries in Asclepieia, of which there were more than 400 in the Mediterranean area and surrounding countries. The Asclepieia were of different design, but usually included a temple dedicated to the god, as well as inscriptions [iamata] with information on the patients who were healed, a sacred bath, a well and a room [abaton] for so-called incubation sleep where the patient would spend the night. Asclepius traditionally appeared to the patients in a vision in the course of the night and an immediate miraculous healing could take place, or advice was given regarding the future treatment of the patient, which was in the morning thereafter discussed by the temple personnel. It is said that the Asclepian cult, a religious healing programme, complemented secular treatment since the tempel personnel were in contact with contemporary Hippocratic medicine. The emotional impact of the incubation sleep and dreams could have had a healing impact on ailments with a psycological basis. The final disappearance of the Asclepian cult was the result of the rise of Christianity, rather than the decline of its healing effectiveness.
Energy Absorption Performance of Meso-Scale Discontinuous Carbon Fibre Composites
Authors: Turner Thomas , Harper Lee , Warrior Nicholas , Caliskan Ari
Published: April 2011

Discontinuous carbon fibre composites are increasingly being considered for use in automotive crash energy management structures. Discontinuous fibres represent a route to high speed, low cost automated manufacture, either in the form of moulding compound, advanced moulding compound or directed fibre preforming approaches. In this work 40 discontinuous 6K high strength carbon / epoxy tubes have been preformed and manufactured for testing. Variables were fibre length (30mm, 60mm, and 90mm), specimen shape (circular or square) and thickness (2.54mm and 5.08mm). Mouldings were cut into 4 specimens and tested both quasi-statically at 1.6e-4m/s and dynamically at 5m/s. Average specific energy absorption (SEA) was 62.5kJ/kg for static and 43kJ/kg for dynamic. The optimum fibre architecture was a circular tube profile with 30mm long fibres and 5mm wall thickness which gave SEA values of 80.2kJ/kg and 48.4kJ/kg. In-plane mechanical testing was also performed on planar versions of the same fibre architectures to determine whether mesoscopic homogeneity effects which dominate tensile testing affect the energy absorption levels, but poor correlation was observed between tensile and energy absorption results.
Integration of a Composite Crash Absorber in Aircraft Fuselage Vertical Struts
Authors: Heimbs Sebastian , Strobl Florian , Middendorf Peter
Published: April 2011

A crash absorber element integrated in composite vertical (z-) struts of commercial aircraft fuselage structures was developed, which absorbs energy under crash loads by cutting the composite strut into stripes and crushing the material under bending. The design concept of this absorber element is described and the performance is evaluated experimentally in static, crash and fatigue test series on component and structural level under normal and oblique impact conditions. These tests highlight the robustness of the absorber design as this system worked under various conditions and angles with an impressively high reproducibility. The physics of the energy absorption by high rate material fragmentation are explained and numerical modelling methods in explicit finite element codes for the simulation of the crash absorber are assessed. The real physical fragmentation phenomena can just be approximated in simulations, emphasising that the numerical prediction of composite energy absorption for industrial use cases is still a big challenge.
Modelling of Low Velocity Impact of Laminated Composite Substructures
Authors: Hadavinia Homayoun , Dogan F. , Elmarakbi Ahmed , Khalili S.M.R.
Published: April 2011

Impact is among the important loading scenario which is required to be addressed for fibre reinforced plastics (FRP) materials in ground or space vehicle applications. The failure behaviour of FRP materials under impact loading is a complex process and a detailed analysis of various mode of failure is necessary. In this paper the failure behaviour of laminated carbon fibre reinforced plastic (CFRP) composite structures under impact loading is investigated by conducting numerical simulations using the explicit finite element analysis ANSYS LS-DYNA software [1]. The impact responses and failure behaviours are being investigated by performing a parametric study and sensitivity analysis in which impact velocity, number of plies, incident angle, friction between contacted surfaces, impactor mass and the geometry are varied in separate cases. The FE model is validated by comparing the numerical results with other published results and good correlations are achieved.
Multiple Perspectives on Tobacco Use among Youth with Mental Health Disorders and Addictions
Authors: Morris Chad D. , May Mandy G. , Devine Karen , Smith Shawn , DeHay Tamara , Mahalik John
Published: April 2011

Purpose.

Youth and young adults with mental health disorders and addictions are at a high risk of becoming nicotine dependent, and at least half will die of tobacco-related diseases. In comparison to the general population, this population also faces neurobiological and psychosocial vulnerabilities. There is a critical need for community services and research targeting tobacco interventions for these individuals.

Methods.

A concurrent mixed methods study was conducted by collecting data from in-depth key informant interviews, focus groups, and a survey. Qualitative key informant interviews with healthcare professionals (n = 11) and youth focus groups (n = 32) were conducted by using semi-structured questioning regarding barriers and facilitators to tobacco interventions. Content analysis was used to code transcripts and categorize themes. Survey data were also collected from 230 smokers ages 13 to 17 years (n = 62) and young adults ages 18 to 25 years (n = 40) at three community mental health centers. The survey inquired about tobacco use, motivation to quit, history of quit attempts, and treatment preferences.

Results.

Five thematic categories were identified in both the adult key informant interviews and the focus groups with youth: (1) motivation to quit, (2) cessation treatment needs, (3) social influence, (4) barriers to treatment, and (5) tobacco-free policy. Among those surveyed, 44% currently smoked. Youth and young adult survey respondents who smoked were often motivated to quit, few had used proven tobacco cessation aids, but there was interest in access to nicotine replacement therapy.

Conclusion.

Merged qualitative and quantitative findings support past literature regarding youth in the general population but also expand upon our knowledge of issues specific to youth and young adults with mental health disorders and addictions. Findings suggest interventions warranting further attention in community treatment settings. (Am J Health Promot 2011;25[5 Supplement]:S31-S37.)
The Pittsburgh STOP Program: Disseminating an Evidence-Informed Intervention for Low-Income Pregnant Smokers
Authors: Cluss Patricia A. , Levine Michele D. , Landsittel Douglas
Published: April 2011

Purpose.

Prenatal smoking is a preventable risk factor for poor perinatal outcomes and is more prevalent in pregnant smokers of low socioeconomic status (SES). We describe the intervention model and factors associated with quitting from the Pittsburgh STOP Program, an evidence-informed dissemination intervention for low-SES pregnant smokers.

Setting.

STOP is delivered in community health care clinics serving economically disadvantaged women.

Participants.

Participants were 856 pregnant women who were current smokers (93%) and recent quitters (7%). Most were white (59%) or black (35%), single (74%), young (mean age = 25), and experiencing an unplanned pregnancy (84%); 90% were insured by Medicaid/uninsured.

Methods.

An evidence-informed intervention for community pregnant women was delivered individually in a single-group pre-post evaluation design. Measures were demographics, participation and retention, smoking status, satisfaction, and cost. Analyses included descriptive statistics and logistic regression.

Results.

Participants attended an average of 4.7 sessions. Dropout rate after the first session was 5%. Over 11% of smokers quit; 48% of preenrollment spontaneous quitters remained abstinent. Factors significantly associated with quitting included race, mother's age, nicotine dependence, and number of sessions attended.

Limitations.

STOP is a community program with self-selected participants and no control group.

Conclusion.

Low-income pregnant smokers will engage in an evidence-informed cessation program tailored for this group, with quit rates that compare to controlled research results. (Am J Health Promot 2011;25[5 Supplement]:S75-S81.)
A National Mass Media Smoking Cessation Campaign: Effects by Race/Ethnicity and Education
Authors: Vallone Donna M. , Niederdeppe Jeff , Richardson Amanda Kalaydjian , Patwardhan Pallavi , Niaura Raymond , Cullen Jennifer
Published: April 2011

Purpose.

To assess the effectiveness of a large-scale, national smoking cessation media campaign, the EX campaign, across racial/ethnic and educational subgroups.

Design.

A longitudinal random-digit-dial panel study conducted prior to and 6 months following the national launch of the campaign.

Setting.

The sample was drawn from eight designated media markets in the United States.

Subjects.

The baseline survey was conducted on 5616 current smokers, aged 18 to 49 years, and 4067 (73% follow-up response rate) were resurveyed at the 6-month follow-up.

Measures.

The primary independent variable is confirmed awareness of the campaign advertising, and the outcome variables are follow-up cessation-related cognitions index score and quit attempts.

Analysis.

Multivariable logistic and linear regression analyses were conducted within racial/ethnic and educational strata to assess the strength of association between confirmed awareness of campaign advertising and cessation-related outcomes.

Results.

Confirmed awareness of campaign advertising increased favorable cessation-related cognitions among Hispanics and quit attempts among non-Hispanic blacks, and increased favorable cessation-related cognitions and quit attempts among smokers with less than a high school education.

Conclusions.

These results suggest that the EX campaign may be effective in promoting cessation-related cognitions and behaviors among minority and disadvantaged smokers who experience a disproportionate burden of tobacco-related illness and mortality. (Am J Health Promot 2011;25[5 Supplement]:S38–S50.)
Exploring causes of interannual variability in the seasonal cycles of tropospheric nitrous oxide
Authors: Nevison C. D. , Dlugokencky E. , Dutton G. , Elkins J. W. , Fraser P. , Hall B. , Krummel P. B. , Langenfelds R. L. , O'Doherty S. , Prinn R. G. , Steele L. P. , Weiss R. F.
Published: April 2011

Abstract. Seasonal cycles in the mixing ratios of tropospheric nitrous oxide (N2O) are derived by detrending long-term measurements made at sites across four global surface monitoring networks. The detrended monthly data display large interannual variability, which at some sites challenges the concept of a "mean" seasonal cycle. In the Northern Hemisphere, correlations between polar winter lower stratospheric temperature and detrended N2O data, around the month of the seasonal minimum, provide empirical evidence for a stratospheric influence, which varies in strength from year to year and can explain much of the interannual variability in the surface seasonal cycle. Even at sites where a strong, competing, regional N2O source exists, such as from coastal upwelling at Trinidad Head, California, the stratospheric influence must be understood to interpret the biogeochemical signal in monthly mean data. In the Southern Hemisphere, detrended surface N2O monthly means are correlated with polar spring lower stratospheric temperature in months preceding the N2O minimum, providing empirical evidence for a coherent stratospheric influence in that hemisphere as well, in contrast to some recent atmospheric chemical transport model (ACTM) results. Correlations between the phasing of the surface N2O seasonal cycle in both hemispheres and both polar lower stratospheric temperature and polar vortex break-up date provide additional support for a stratospheric influence. The correlations discussed above are generally more evident in high-frequency in situ data than in data from weekly flask samples. Furthermore, the interannual variability in the N2O seasonal cycle is not always correlated among in situ and flask networks that share common sites, nor do the mean seasonal amplitudes always agree. The importance of abiotic influences such as the stratospheric influx and tropospheric transport on N2O seasonal cycles suggests that, at sites remote from local sources, surface N2O mixing ratio data by themselves are unlikely to provide information about seasonality in surface sources, e.g., for atmospheric inversions, unless the ACTMs employed in the inversions accurately account for these influences. An additional abioitc influence is the seasonal ingassing and outgassing of cooling and warming surface waters, which creates a thermal signal in tropospheric N2O that is of particular importance in the extratropical Southern Hemisphere, where it competes with the biological ocean source signal.
Possible catalytic effects of ice particles on the production of NOx by lightning discharges
Authors: Peterson H. S. , Beasley W. H.
Published: April 2011

Abstract. It is well known that lightning produces NOx as a result of the high temperatures in discharge channels. Since most viable proposed electrification mechanisms involve ice crystals, it is reasonable to assume that lightning discharge channels frequently pass through fields of ice particles of various kinds. We address the question of whether ice crystals may serve as catalysts for the production of NOx by lightning discharges. If so, and if the effect is large, it would need to be taken into account in estimates of global NOx production by lightning. In this study, we make a series of plausible assumptions about the temperature and concentration of reactant species in the environment of discharges and we postulate a mechanism by which ice crystals are able to adsorb nitrogen atoms. We then compare production rates between uncatalyzed and catalyzed reactions at 2000 K, 3000 K, and 4000 K, which are reasonable temperatures in lightning channels as they cool down. Catalyzed NO production rates are greater at 2000 K, whereas uncatalyzed production rates are greater at 4000 K. This effect may be relevant to the question of the relative importance of cloud-to-ground and in-cloud lightning for NOx production.
MAMAP – a new spectrometer system for column-averaged methane and carbon dioxide observations from aircraft: retrieval algorithm and first inversions for point source emission rates
Authors: Krings T. , Gerilowski K. , Buchwitz M. , Reuter M. , Tretner A. , Erzinger J. , Heinze D. , Burrows J. P. , Bovensmann H.
Published: April 2011

Abstract. MAMAP is an airborne passive remote sensing instrument designed for measuring columns of methane (CH4) and carbon dioxide (CO2). The MAMAP instrument consists of two optical grating spectrometers: One in the short wave infrared band (SWIR) at 1590–1690 nm to measure CO2 and CH4 absorptions and another one in the near infrared (NIR) at 757–768 nm to measure O2 absorptions for reference purposes. MAMAP can be operated in both nadir and zenith geometry during the flight. Mounted on an airplane MAMAP can effectively survey areas on regional to local scales with a ground pixel resolution of about 29 m × 33 m for a typical aircraft altitude of 1250 m and a velocity of 200 km h−1. The retrieval precision of the measured column relative to background is typically ≲ 1% (1σ). MAMAP can be used to close the gap between satellite data exhibiting global coverage but with a rather coarse resolution on the one hand and highly accurate in situ measurements with sparse coverage on the other hand. In July 2007 test flights were performed over two coal-fired powerplants operated by Vattenfall Europe Generation AG: Jänschwalde (27.4 Mt CO2 yr−1) and Schwarze Pumpe (11.9 Mt CO2 yr−1), about 100 km southeast of Berlin, Germany. By using two different inversion approaches, one based on an optimal estimation scheme to fit Gaussian plume models from multiple sources to the data, and another using a simple Gaussian integral method, the emission rates can be determined and compared with emissions as stated by Vattenfall Europe. An extensive error analysis for the retrieval's dry column results (XCO2 and XCH4) and for the two inversion methods has been performed. Both methods – the Gaussian plume model fit and the Gaussian integral method – are capable of delivering reliable estimates for strong point source emission rates, given appropriate flight patterns and detailed knowledge of wind conditions.
Enhanced decomposition offsets enhanced productivity and soil carbon accumulation in coastal wetlands responding to climate change
Authors: Kirwan M. L. , Blum L. K.
Published: April 2011

Abstract. Coastal wetlands are responsible for about half of all carbon burial in oceans, and their persistence as a valuable ecosystem depends largely on the ability to accumulate organic material at rates equivalent to relative sea level rise. Recent work suggests that elevated CO2 and temperature warming will increase organic matter productivity and the ability of marshes to survive sea level rise. However, we find in a series of preliminary experiments that organic decomposition rates increase by about 20% per degree of warming. Our measured temperature sensitivity is similar to studies from terrestrial systems, three times as high as the response of salt marsh productivity to temperature warming, and greater than the productivity response associated with elevated CO2 in C3 marsh plants. Although the experiments were simple and of short duration, they suggest that enhanced CO2 and warmer temperatures could actually make marshes less resilient to sea level rise, and tend to promote a release of soil carbon. Simple projections indicate that elevated temperatures will increase rates of sea level rise more than any acceleration in organic matter accumulation, suggesting the possibility of a positive feedback between climate, sea level rise, and carbon emissions in coastal environments.
MADE-in: a new aerosol microphysics submodel for global simulation of insoluble particles and their mixing state
Authors: Aquila V. , Hendricks J. , Lauer A. , Riemer N. , Vogel H. , Baumgardner D. , Minikin A. , Petzold A. , Schwarz J. P. , Spackman J. R. , Weinzierl B. , Righi M. , Dall'Amico M.
Published: April 2011

Abstract. Black carbon (BC) and mineral dust are among the most abundant insoluble aerosol components in the atmosphere. When released, most BC and dust particles are externally mixed with other aerosol species. Through coagulation with particles containing soluble material and condensation of gases, the externally mixed particles may obtain a liquid coating and be transferred into an internal mixture. The mixing state of BC and dust aerosol particles influences their radiative and hygroscopic properties, as well as their ability of forming ice crystals. We introduce the new aerosol microphysics submodel MADE-in, implemented within the ECHAM/MESSy Atmospheric Chemistry global model (EMAC). MADE-in is able to track mass and number concentrations of BC and dust particles in their different mixing states, as well as particles free of BC and dust. MADE-in describes these three classes of particles through a superposition of seven log-normally distributed modes, and predicts the evolution of their size distribution and chemical composition. Six out of the seven modes are mutually interacting, allowing for the transfer of mass and number among them. Separate modes for the different mixing states of BC and dust particles in EMAC/MADE-in allow for explicit simulations of the relevant aging processes, i.e. condensation, coagulation and cloud processing. EMAC/MADE-in has been evaluated with surface and airborne measurements and mostly performs well both in the planetary boundary layer and in the upper troposphere and lowermost stratosphere.
The natech events during the 17 August 1999 Kocaeli earthquake: aftermath and lessons learned
Authors: Girgin S.
Published: April 2011

Abstract. Natural-hazard triggered technological accidents (natechs) at industrial facilities have been recognized as an emerging risk. Adequate preparedness, proper emergency planning, and effective response are crucial for the prevention of natechs and mitigation of the consequences. Under the conditions of a natural disaster, the limited resources, the possible unavailability of mitigation measures, and the lack of adequate communication complicate the management of natechs. The analysis of past natechs is crucial for learning lessons and for preventing or preparing for future natechs. The 17 August 1999, Kocaeli earthquake, which was a devastating disaster hitting one of the most industrialized regions of Turkey, offers opportunities in this respect. Among many natechs that occurred due to the earthquake, the massive fire at the TUPRAS Izmit refinery and the acrylonitrile spill at the AKSA acrylic fiber production plant were especially important and highlight problems in the consideration of natechs in emergency planning, response to industrial emergencies during natural hazards, and information to the public during and following the incidents. The analysis of these events shows that even the largest and seemingly well-prepared facilities can be vulnerable to natechs if risks are not considered adequately.
An approach for flood hazard modelling and mapping in the medium Valtellina
Authors: Poretti I. , De Amicis M.
Published: April 2011

Abstract. In the Lombardy Region, as in many other contexts all over the world, hazard maps do not have a precise legislative confirmation. Despite this, they are necessary to support several institutional activities, and among these, local urban planning. An approach to hazard analysis and mapping that fits the Lombardy Region legislative framework is presented here that introduces a level of experimental modelling, making use of SOBEK 1-D–2-D as a tool for hydrodynamic simulations. A stretch of 17 km of the Adda river in Valtellina has been modelled, referring to twelve scenarios characterised by different temporal probabilities, and comprising the main sources of uncertainty. The results were compared with available local hydraulic studies, and combined to obtain two complementary flood hazard maps which could usefully support urban planning. Advantages and drawbacks of this modelling approach, together with considerations related to flood hazard mapping are discussed.
An eddy resolving tidal-driven model of the South China Sea assimilating along-track SLA data using the EnOI
Authors: Xie J. , Counillon F. , Zhu J. , Bertino L.
Published: April 2011

Abstract. The upper ocean circulation in the South China Sea (SCS) is driven by the Asian monsoon, the Kuroshio intrusion through the Luzon Strait, strong tidal currents, and a complex topography. Here, we demonstrate the benefit of assimilating along-track altimeter data into a nested configuration of the HYbrid Coordinate Ocean Model that includes tides. Including tides in models are important because they interact with the main circulation. However, assimilation of altimetry data into a model including tides is challenging because tides and mesoscales features contribute to the elevation of ocean surface at different time scales and require different corrections. To address this issue, tides are filtered out of the model output and only the mesoscale variability is corrected with a computationally cheap data assimilation method: the Ensemble Optimal Interpolation (EnOI). The method uses a running selection of members to handle the seasonal variability and assimilates the track data asynchronously. The data assimilative system is tested for the period 1994–1995, during which time a large number of validation data are available. Data assimilation reduces the Root Mean Square Error of Sea Level Anomalies from 9.3 cm to 6.9 cm and improves the representation of the mesoscale features. With respect to the vertical temperature profiles, the data assimilation scheme improves the results at intermediate depth, but a slight degradation of the results at the surface is noted. The comparison to surface drifters shows an improvement of surface current by approximately −8.3%, with largest improvements in the Northern SCS and east of Vietnam.
Application of asymptotic radiative transfer theory for the retrievals of snow parameters using reflection and transmission observations
Authors: Negi H. S. , Kokhanovsky A. , Perovich D. K.
Published: April 2011

Abstract. An asymptotic analytical radiative transfer (AART) theory was used to retrieve snow optical parameters such as extinction coefficient, diffuse exponent, asymptotic flux extinction coefficient (AFEC), snow optical thickness and probability of photon absorption (PPA). This theory was applied to the reflection and transmission data for a temperate snow cover from 400–1000 nm wavelength region, to retrieve AFEC for different types of snow cover (thick, thin, dry, wet, new and old snow). The AFEC values were found at 450 nm wavelength region in the range from 0.06 to 0.22 cm−1, where high values were observed for increased wetness and impurity in snow. A good agreement between AART retrieved and other radiative transfer model retrieved parameter shows that AART theory can work well for different types of snow. The extinction coefficients for temperate snow ranged from 0.5 to 1.0 mm−1 and the e-folding depths ranged from 5 to 25 cm. The snow physical characteristics such as grain size and density were also retrieved using derived optical parameters and found in agreement with ground measurements. The main advantages of the proposed AART method are the simple analytical equations that provide a valuable alternative from complex numerical radiative transfer solutions.
A Parametrical Analysis on the Elastic Anisotropy of Woven Hierarchical Tissues
Authors: Chen Qiang , Pugno Nicola M.
Published: April 2011

In this paper, the elastic properties of 2‐D woven hierarchical tissues are modeled, considering matrix transformation and stiffness averaging, assuming the warp and fill yarns (level 0) an orthotropic material. The tissue at level 1 is considered as the fabric composed of warp and fill yarns at level 0. Warp and fill yarns at level 1 are defined as “pieces” of such 1‐level tissue and have a different mismatch between the inclination of their longitudinal axes and those of the composing sub‐fibers. Similarly, based on warp and fill yarns at level 1, we generate warp and fill yarns at level 2 and thus tissues with two hierarchical levels, and so on. We compare our theory with experiments on tendons from the literature and on leaves performed by ourselves. The result shows the possibility of designing a new class of hierarchical 2‐D scaffolds by tailoring the elastic anisotropy, better matching the anisotropy of the biological tissues and thus maximizing their regeneration at each hierarchical level.
A study of the three‐dimensional particle size segregation structure in a rotating drum
Authors: Huang A. N. , Kuo H. P.
Published: April 2011

Three‐dimensional particle size segregation structures of binary mixtures of six different size ratios (SR = 1.42–3.37) in a rotating drum are studied. The formation of two smaller particle satellites around the central smaller‐particle rich band after the band formation core‐thickening mechanism is reported for the first time. The binary mixtures of six SRs show three satellite shapes, including the small bump shape, the axe shape, and the hemisphere shape. Except for the binary mixture of SR = 2.01 with the axe satellite shape, the satellite size increases with the increasing of the SR value at the same bed depth. The degrees of mixing of binary mixtures of six different SRs at different bed depths are analyzed using the Lacey mixing index. The degree of mixing at the bed surface and close to the drum cylindrical wall can be explained by the drift‐diffusional model of Savage (1993). © 2011 American Institute of Chemical Engineers AIChE J, 2012
Synthesis and characterization of conductive nanoblends based on poly(aniline‐co‐3‐aminobenzoic acid) in the presence of poly(styrene‐alt‐maleic acid)
Authors: Zareh Ehsan Nazarzadeh , Moghadam Peyman Najafi
Published: April 2011

In this article, we describe electrically conductive nanoblends containing poly(aniline‐co‐3‐ aminobenzoic acid) (PANABA), poly(styrene‐alt‐maleic acid) (PSMAC), and polystyrene. PANABA copolymers on a nanoscale were prepared under ultrasonic irradiation by the oxidative copolymerization of aniline and 3‐aminobenzoic acid at different molar ratios. PSMAC was also prepared in our laboratory. The obtained conductive nanoblends formed films with good homogeneity and flexibility. The conductivity of the obtained nanoblends was measured with a four‐probe method. The maximum electrical conductivity obtained was 0.60 S/cm. The characterization of the obtained copolymers and nanoblends was carried out by Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, and X‐ray diffraction. Scanning electron microscopic images were taken from the obtained nanoblends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A new biosynthetic material and its potential application domains
Authors: Mocanu Georgeta , Mihai Doina , Ionescu Corina , Voicu Anca , Moscovici Misu
Published: April 2011

A polysaccharide was obtained by fermentation of glycerol in the presence of Pseudomonas spp. bacteria. It was characterized by FTIR spectroscopy, SEC chromatography, conductimetric titrations, and viscometric measurements; its emulsifying activity was tested using various mixtures of a hydrocarbon compound and polymer solution. Based on this polysaccharide, new crosslinked ionic derivatives were synthesized and characterized; their interaction with lysozyme was studied. From the data presented, one can suggest some applications for this new, less expensive polysaccharide—it could be used as a thickener and specific bioemulsifier, while its derivatives—as a support for controlled release of biomolecules. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Fabrication and absorption intensity analyses of Er2O3 nanoparticles suspended in polymethyl methacrylate
Authors: Chandra Sreerenjini , Gruber John B. , Burdick Gary W. , Sardar Dhiraj K.
Published: April 2011

Nanoparticles suspended in polymeric host materials are found to have tremendous potential for various photonic and biological applications due to their unique material properties. Polymethyl methacrylate (PMMA) is known to be one of the best vinyl polymers owing to its excellent dimensional quality, weather resistance, easiness of synthesis, resistance to laser damage, and high mechanical strength. In this article, we describe a methodology to fabricate thin discs of nanocrystalline erbium oxide (Er2O3) suspended in PMMA (Er2O3/PMMA). The optical transparency of PMMA was confirmed in the ultraviolet, visible, and the near‐infrared regions of the electromagnetic spectrum, making it possible to observe only the Er2O3 spectra over the wavelength investigated. The room‐temperature absorption spectrum of Er2O3/PMMA has been taken in the 400 to 820 nm wavelength region. Analysis of the spectrum reveals a consistent agreement between our experimental data and those reported earlier for Er3+ in nanocrystalline Er3+ : Y2O3. A solid solution exists between Er2O3 and Er3+ : Y2O3 in terms of their physical properties. Therefore, our experimental results conclude that the presence of PMMA does not significantly alter the crystal symmetry as well as the co‐ordination environment of the Er3+ ions in Er2O3. Our results also emphasize that the Er2O3/PMMA may have future possibilities for numerous technological applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and characterization of bile acid‐based poly β amino esters for paclitaxel delivery
Authors: Gangwal Jitendra J. , Kulkarni Mohan G.
Published: April 2011

New biodegradable poly β amino esters were synthesized by the polymerization of Deoxycholic acid (DOCA) in all the structural planes by 1, 4 addition of Trimethylene dipiperidine (TMDP) to diacrylates of Deoxycholyl glycol, Methyl deoxycholate and Trimethylolpropane deoxycholate esters. 1H‐NMR, 13C‐NMR and IR studies confirmed presence of amine and Deoxycholyl units in polymers. XRD and TGA studies indicated that all the polymers were amorphous and thermostable up to 300°C. DSC studies revealed glass transition temperature (Tg) in the range 70–80°C. All the polymers degraded very slowly in the buffers of pH 1.1, 7.4 and 10 because of the hydrophobic nature of Deoxycholate units. These polymers also exhibited pH sensitivity due to the incorporation of amines along with Deoxycholate units in the backbone. P‐Nitroaniline (PNA) release followed anomalous release kinetics. Paclitaxel (PTX) loaded nanospheres prepared from these polymers were spherical and uniform in the size range 75–250 nm and 0.4–1μ depending upon the method of preparation. PTX loading was in the range 60–90%, while release (up to 20–60%) was sustained over a period of 100 h. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Fabrication and characterization of poly‐γ‐glutamic acid nanofiber
Authors: Tajima Takeharu , Ueno Seiichiro , Yabu Naoyasu , Sukigara Sachiko , Ko Frank
Published: April 2011

Poly‐γ‐glutamic acid (γ‐PGA) is a natural polymer that is widely recognized as a component in the viscous filaments of fermented soybean (natto). γ‐PGA is known for its superior biodegradability, biocompatibility and water retention characteristics. Crosslinked γ‐PGA is commonly used as a hydrogel, but it is not used in the fiber form because it is soluble in water. In this study, we demonstrate the use of γ‐PGA‐Na for production of water insoluble γ‐PGA nanofibers by electrospinning. This result was accomplished using an aqueous solvent containing 10 wt % of an oxazoline component polymer as the crosslinking agent and by heat treatment. The crosslinking reaction was evaluated by solid‐state NMR. The nanofiber webs showed a high level of moisture absorption capability while retaining their fibrous shape. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Regioselective catalyzed modification of poly(methylhydro)siloxane using RuRh and RuPt bimetallic dendrimer‐encapsulated nanoparticles
Authors: Peng Xiaohong , Pan Qinmin , Lu Xiaoran
Published: April 2011

RuRh and RuPt bimetallic dendrimer‐encapsulated nanoparticles (DENs) were successfully prepared by a two‐step process involving co‐complexation, using ruthenium and rhodium or ruthenium and platinum complex ions with partially quaternized fifth‐generation poly(amidoamine) (G5‐Q), and then coreduction with NaBH4. UV–vis, transmission electron microscope, and laser scattering analyses were used to characterize the bimetallic alloy DENs. The regioselective synthesis of multifunctional hybrid poly(methylhydro)siloxane was achieved by the RuRh and RuPt alloy nanoparticle catalysts. The experimental results showed that the RuRh and RuPt bimetallic DENs presented higher catalytic activity than physical mixtures of their monometallic DENs, respectively. This should be due to synergistic electronic effect of RuRh and RuPt alloy catalysts. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Intracellular peptide delivery using amphiphilic lipid‐based formulations
Authors: Weiss Amélie , Neuberg Patrick , Philippot Stéphanie , Erbacher Patrick , Weill Claire O.
Published: April 2011

Peptides, highly diverse by their nature, are important biochemical and pharmaceutical tools: ligands for cellular receptors, transcription factors, immunosuppressants, vaccines, etc. As the majority of their targets are intracellular, peptides need to cross the plasma membrane and gain access to the cytoplasm. However, due to their physicochemical properties, most peptides need to be entrapped by a molecular vehicle to be able to reach the cytosol compartment. In this study, we present new biological tools to enhance intracellular peptides delivery. Based on electrostatic interactions, two complementary types of amphiphilic molecules have been designed as delivery vehicles. A diverse set of fluorescently labeled peptides have successfully been delivered. This opens the avenue for the use of peptides combined to delivery vehicles as therapeutic aids. Biotechnol. Bioeng. 2011;108: 2477–2487. © 2011 Wiley Periodicals, Inc.
Simultaneous measurements of cytoplasmic viscosity and intracellular vesicle sizes for live human brain cancer cells
Authors: Margraves Charles , Kihm Kenneth , Yoon Sang Youl , Choi Chang Kyoung , Lee Seong‐ho , Liggett Jason , Baek Seung Joon
Published: April 2011

Intracellular vesicles, comprised of protein clusters, were individually tracked inside human brain cancer cells and characterized to simultaneously determine the average vesicle size and effective cytoplasmic viscosity. The cells were transfected with a TGF‐β superfamily gene, non‐steroidal anti‐inflammatory drug‐Activated Gene‐1 (NAG‐1) tagged with green fluorescent proteins (GFPs). Using total internal reflection fluorescent microscopy (TIRFM) the individual movements of the vesicles were categorized into either Brownian, caged, or directional type motion. In the near‐field region confined by the evanescent wave field of TIRFM, the hindrance of these vesicles was created by interactions with the glass coverslip and/or sub‐cellular structures. Measured particle motions were compared with theoretical predictions of hindered motion to estimate the unknown size and viscosity parameters using a nonlinear regression technique. For the tested human brain cancer cells, the average vesicle size and effective intracellular fluid viscosity were calculated to be 496 nm and 0.068 Pa s, respectively. This finding suggests that most of the hindrance experienced by vesicles can be due to non‐hydrodynamic interactions with microtubules and other intracellular structures. It should be also noted that this method provides a way to examine changes in vesicle size due to outside stimulus such as drug interaction, cytotoxicity, etc., unlike standard measurement techniques which require fixing the cells themselves. Biotechnol. Bioeng. 2011;108: 2504–2508. © 2011 Wiley Periodicals, Inc.
Quaternary conformational stability: The effect of reversible self‐association on the fibrillation of two insulin analogs
Authors: Ludwig D. Brett , Webb Jonathan N. , Fernández Cristina , Carpenter John F. , Randolph Theodore W.
Published: April 2011

Under conditions relevant to the manufacturing of insulin (e.g., pH 3, room temperature), biosynthetic human insulin (BHI), and Lispro insulin (Lispro) require a nucleation step to initiate aggregation. However, upon seeding with preformed aggregates, both insulins rapidly aggregate into nonnative fibrils. Far ultraviolet circular dichroism (far‐UV CD) and second derivative Fourier transform infrared (2D‐FTIR) spectroscopic analyses show that the fibrillation process involves a change in protein secondary structure from α‐helical in native insulin to predominantly β‐sheet in the nonnative fibrils. After seeding, Lispro aggregates faster than BHI, likely because of a reduced propensity to reversibly self‐associate. Composition gradient multi‐angle light scattering (CG‐MALS) analyses show that Lispro is more monomeric than BHI, whereas their conformational stabilities measured by denaturant‐induced unfolding are statistically indistinguishable. For both BHI and Lispro, as the protein concentration increases, the apparent first‐order rate constant for soluble protein loss decreases. To explain these phenomena, we propose an aggregation model that assumes fibril growth through monomer addition with competitive inhibition by insulin dimers. Biotechnol. Bioeng. 2011;108: 2359–2370. © 2011 Wiley Periodicals, Inc.
T lymphocyte activation in visceral adipose tissue of patients with oesophageal adenocarcinoma
Authors: Lysaght J , Allott E H , Donohoe C L , Howard J M , Pidgeon G P , Reynolds J V
Published: April 2011

Background

Visceral adipose tissue may fuel obesity-associated chronic inflammation and tumorigenesis. T cells may be important in visceral adipose tissue in driving inflammation, but they have not yet been characterized in patients with cancer. This study aimed to characterize T lymphocytes in visceral adipose tissue and peripheral blood from patients with oesophageal adenocarcinoma.

Methods

Omental fat was taken from 35 patients with oesophageal adenocarcinoma at the start of surgery. Flow cytometry was performed to assess T cell activation status and cytokine production in omentum and peripheral blood.

Results

A large population of lymphocytes was present in the omentum. Omental CD4+ and CD8+ T cells displayed significantly enhanced expression of the T cell activation markers CD69 (P < 0·001) and CD107a (CD8+ T cells: P < 0·01), and significantly decreased CD62L expression (P < 0·05), compared with blood. Significantly higher proportions of CD45RO+ T cells compared with CD45RA+ T cells were present in omentum (P < 0·001 and P = 0·012 for CD4+ and CD8+ cells respectively). Interferon γ was the most abundant cytokine expressed by omental T cells, with a significantly higher level than in blood and subcutaneous adipose tissue (P < 0·01).

Conclusion

Visceral adipose tissue is a rich source of activated proinflammatory CD4+ and CD8+ T cells. It may fuel chronic inflammation via T cell-mediated pathways.