bluuebunny/crossref_metadata_2025 huggingface dataset:
The mediating effects of dietary habits on the relationship between television viewing and body mass index among youth
Authors: Carson Valerie , Janssen Ian
Published: March 2012

Objective

There is evidence to suggest that excessive television viewing is an independent determinant of obesity in young people. However, the pathways between television viewing and obesity are not fully understood. Therefore, the purpose of this study was to examine whether the relationship between television and body mass index (BMI) is mediated by television snacking and junk food consumption.

Methods

Results are based on 15 973 youth in grades 6–10 who participated in the Canadian 2009/2010 Health Behaviour in School‐Aged Children Survey (HBSC). Participants self‐reported their weight and height and BMI z‐scores were calculated based on World Health Organization growth standards. Participants reported the frequency of snacking while watching television and the frequency of eating junk food (sweets, soft drinks, baked goods, French fries, potato chips). Total hours per week of television were calculated. A contemporary multiple mediation analysis was used to examine associations.

Results

A modest positive relationship was observed between television viewing and BMI. The mean BMI z‐score was 0.15 units higher in youth in the highest television viewing quartile by comparison with the youth in the lowest quartile. However, contrary to our hypothesis, television snacking and junk food consumption were not significant positive mediators of the television and BMI relationship.

Conclusion

The pathways between television viewing and obesity are complicated and remain poorly understood. Future research using longitudinal or experimental designs, more precise measurement tools and formal mediation analyses is needed. This research should consider mediators related to both energy intake and expenditure.
Secondary electron deposition mechanism of carbon contamination
Authors: Leontowich Adam F. G. , Hitchcock Adam P.
Published: March 2012

Deposition of a carbonaceous contaminant layer on surfaces exposed to radiation exceeding 7–10 eV is ubiquitous in many fields of research. The mechanism of this deposition process is still debated. A scanning transmission x-ray microscope has been used to create and interrogate carbonaceous deposits with photon energies spanning the C 1s ionization edge. For equal fluence, the rate of carbon deposition is proportional to the x-ray absorption spectrum of the deposited material. The results are consistent with a deposition mechanism involving secondary electrons. Implications of this measurement with regard to future generations of high volume photolithography are discussed.
Carbon Isotope Constraints on the Deglacial CO
2
Rise from Ice Cores
Authors: Schmitt Jochen , Schneider Robert , Elsig Joachim , Leuenberger Daiana , Lourantou Anna , Chappellaz Jérôme , Köhler Peter , Joos Fortunat , Stocker Thomas F. , Leuenberger Markus , Fischer Hubertus
Published: March 2012

By the Numbers

As carbon dioxide is exchanged between the atmosphere, the oceans, and the terrestrial biosphere, its carbon isotopic composition is modified by various processes involved in its transfer between the different reservoirs. The carbon isotopic composition of the carbon dioxide contained in bubbles of air trapped in ice cores thus provides a record of the processes that regulated the composition of the atmosphere in the past. Using data from three Antarctic ice cores,

Schmitt
et al.

(p.
711
, published online 29 March; see the Perspective by

Brook

) present a record of the carbon isotopic makeup of atmospheric CO
2
for the past 24,000 years. The findings reveal the dominant role of the oceans during the early part of the deglaciation and the effects of the regrowth of the terrestrial biosphere later in the deglacial transition. Before the deglaciation, during the Last Glacial Maximum, the carbon cycle was essentially at equilibrium.
First Case Report of Bloodstream Infection Due to a Candida Species Closely Related to the Novel Species Candida pseudorugosa
Authors: Taverna Constanza Giselle , Córdoba Susana , Isla Guillermina , Fernández Norma , García Susana , Mazza Mariana , Murisengo Omar Alejandro , Vivot Walter , Szusz Wanda , Davel Graciela , Tiraboschi Iris Nora , Bosco-Borgeat María Eugenia
Published: March 2012

Candida pseudorugosa
is a novel species closely related to
Candida rugosa
for which only one case has been reported. We report the first case of a bloodstream infection in humans caused by a
Candida
sp. closely related to
C. pseudorugosa
. We contribute evidence to show this organism as a potential human pathogen that may be misidentified by conventional methods, also pointing out its lower sensitivity to azoles and other antifungal agents.
Correlation of Clinical Outcomes with β-Glucan Levels in Patients with Invasive Candidiasis
Authors: Sims Charles R. , Jaijakul Siraya , Mohr John , Rodriguez Jose , Finkelman Malcolm , Ostrosky-Zeichner Luis
Published: March 2012

The correlation of β-glucan (BG) levels with clinical outcomes in invasive candidiasis (IC) remains unknown. Patients with proven IC were followed prospectively from diagnosis to outcome with twice-weekly serum BG sampling. Correlation of BG with clinical outcome was assessed in each patient. BG levels tend to decrease in successfully treated patients and increase in treatment failures. BG levels may be useful as surrogates for outcome evaluation of IC.
A Molecular Approach to Identification and Profiling of First-Line-Drug-Resistant Mycobacteria from Sputum of Pulmonary Tuberculosis Patients
Authors: Chowdhury Imran Hussain , Sen Aditi , Bahar Bojlul , Hazra Avijit , Chakraborty Urmita , Choudhuri Subhadip , Goswami Avranil , Pal Nishith Kumar , Bhattacharya Basudev
Published: March 2012

Conventional and molecular techniques were applied to detect and characterize drug resistance of mycobacteria in the sputum samples of clinically confirmed tuberculosis. The sensitivities of mycobacterium detection by ZN staining, culture, multiplex PCR, and restriction fragment length polymorphism (RFLP) were 27.7%, 19.9%, 92.9%, and 95.7%, respectively, but all were 100% specific. The conventional and multiple-allele-specific PCR (MAS-PCR) methods enabled establishment of the drug resistance in 19.3% and 86.9% cases, respectively. We demonstrated that molecular techniques have potential in the accurate diagnosis of tuberculosis.
Effects of Electroacupuncture on Stress-Related Symptoms in Medical Students: A Randomised Controlled Pilot Study
Authors: Dias Marcio , Pagnin Daniel , de Queiroz Pagnin Valéria , Reis Regina Lucia Ribeiro , Olej Beni
Published: March 2012

Objective

To assess the effects of electroacupuncture on stress-related symptoms—sleep disorders, anxiety, depression and burnout—in medical students, and provide data to inform a power analysis to determinate numbers for future trials.

Methods

Twenty-five students were randomly assigned to an electroacupuncture (n=12) group or control group (n=13) that did not receive treatment. Electroacupuncture was applied at a continuous frequency 2 Hz for 20 min once a week for 8 weeks at sites on the extremities, face, ear and scalp. The outcomes of the students treated with electroacupuncture were compared with those of the control group at the endpoint, controlling the influence of baseline scores. The instruments used were self-administered questionnaires that comprised the validated Portuguese version of the mini-sleep questionnaire (MSQ), the Pittsburgh sleep quality index (PSQI), the Epworth sleepiness scale (ESS), the Beck depression inventory (BDI), the Beck anxiety inventory, the Maslach burnout inventory–student survey (MBI–SS), and World Health Organization quality of life assessment – abbreviated version (WHOQOL–bref).

Results

The medical students treated with electroacupuncture showed a significant decrease compared with the control group for MSQ scores (p=0.04) and PSQI (p=0.006). After treatment, 75% students in the electroacupuncture group presented a good sleep quality, compared with 23.1% of the students in the control group. No significant difference on daytime sleepiness was shown by the ESS. The electroacupuncture group showed significant improvement on depressive symptoms (BDI), the emotional exhaustion and cynicism dimensions of burnout (MBI–SS) and physical health (WHOQOL–bref).

Conclusions

Electroacupuncture was associated with a significant reduction of stress-related symptoms, but because of the study design the authors cannot say what proportion of the reduction was due to needle stimulation.
Expression of melanoma differentiation associated gene 5 is increased in human gastric mucosa infected withHelicobacter pylori
Authors: Tatsuta Tetsuya , Imaizumi Tadaatsu , Shimoyama Tadashi , Sawaya Manabu , Kunikazu Tanji , Matsumiya Tomoh , Yoshida Hidemi , Satoh Kei , Fukuda Shinsaku
Published: March 2012

Helicobacter pyloriinfection is associated with gastroduodenal diseases. Melanoma differentiation associated gene 5 (MDA5) plays a role in antiviral host defense. We investigated the effect ofH pyloriinfection on MDA5 expression in human gastric mucosa. Biopsy samples from the antrum and corpus were obtained from 33 patients. MDA5 mRNA and protein were examined by real-time PCR and immunohistochemical staining. Histological gastritis was graded according to updated Sydney System. MDA5 mRNA was significantly increased in the antrum infected withH pylori. MDA5 protein positively stained in infiltrating mononuclear cells. MDA5 mRNA expression was significantly correlated with the grade of glandular atrophy (rs = 0.767) and intestinal metaplasia (rs = 0.748) in the corpus withH pyloriinfection. These results indicate that MDA5 may be involved in innate immune reactions againstH pyloriand associate with glandular atrophy and intestinal metaplasia in patients withH pyloriinfection.
First case of Hb Fontainebleau with sickle haemoglobin and other non-deletional α gene variants identified in neonates during newborn screening for sickle cell disorders
Authors: Upadhye Dipti S , Jain Dipty , Nair Sona B , Nadkarni Anita H , Ghosh Kanjaksha , Colah Roshan B
Published: March 2012

Objective

To evaluate the significance of non-deletional α gene variants identified in neonates during newborn screening for sickle cell disorders.

Methods

1534 newborn babies were screened in the last 2 years for sickle cell disease using a targeted screening approach. Investigations included a complete blood count, high performance liquid chromatography analysis, cellulose acetate electrophoresis (pH 8.9), heat stability test, restriction digestion and Amplified Refractory Mutation System for confirmation of sickle haemoglobin (Hb S), α genotyping by multiplex PCR and DNA sequencing.

Results

Three non-deletional α gene variants, Hb Fontainebleau, Hb O Indonesia and Hb Koya Dora, were identified in heterozygous condition in newborns. This is the first report of Hb Fontainebleau in association with Hb S. The baby had anaemia at birth (Hb 11.4 g/dl) with no cyanosis, icterus or need for transfusion. She had occipital encephalocoele and was operated on day 24 to remove the mass. The baby diagnosed with Hb O Indonesia in combination with Hb S also had a low haemoglobin level of 12.7 g/dl.

Conclusion

Newborn screening for sickle cell disorders also enabled us to identify three α globin chain variants. Two babies who inherited Hb Fontainebleau and Hb O Indonesia along with Hb S had reduced Hb levels at birth and need to be followed up.
Characteristics of emodin on modulating the contractility of jejunal smooth muscle
Authors: Chen Dapeng , Xiong Yongjian , Wang Li , Lv Bochao , Lin Yuan
Published: March 2012

Emodin is traditionally used as a laxative and is found to increase or decrease the contractility of intestinal smooth muscle in low doses and high doses, respectively. In this study, we propose that bidirectional regulation (BR) on the contractility of jejunal smooth muscle (CJSM) is inducible by emodin in the absence of control by the central nervous system. The results indicated that emodin-induced BR had the following characteristics. A stimulatory effect on CJSM was induced by emodin at 7 low contractile states, and an inhibitory effect was induced on CJSM at 7 high contractile states. Emodin-induced BR on myosin phosphorylation was also observed. BR was not observed in the presence of tetrodotoxin, suggesting that enteric nervous system is required for producing BR. The stimulatory effect of emodin on CJSM was abolished by atropine and diphenhydramine, respectively, suggesting that BR was correlated with cholinergic and histamine system while jejunal smooth muscle was at low contractile state. The inhibitory effect of emodin on CJSM was abolished by phentolamine, propranolol, and L-NG-nitroarginine (L-NNA), respectively, suggesting that BR was related to adrenergic hyperactivity and with a nitric oxide relaxing mechanism while jejunal smooth muscle was in a high contractile state. The exact mechanism, however, needs further investigation.
Upregulation of platelet L-arginine – nitric oxide pathway after exercise training in hypertension
Authors: Matsuura Cristiane , Brunini Tatiana M.C. , Mury Wanda V. , Garcia-Pinto Angelica B. , Carvalho Jorge J. , Mendes-Ribeiro Antonio Cláudio
Published: March 2012

We investigated whether physical exercise can affect platelet L-arginine – nitric oxide pathway in spontaneously hypertensive rats (SHR). Sixteen male SHR and 16 Wistar Kyoto rats (WKY) were divided among exercise (EX) and sedentary (SED) groups. After 20 weeks of treadmill training, systolic blood pressure (mm Hg) was significantly lower in exercised spontaneously hypertensive rats (SHR/EX; 138 ± 8) than in sedentary spontaneously hypertensive rats (SHR/SED; 214 ± 9). Exercise significantly increased platelet L-arginine transport (pmol L-arginine·(109 cells)–1·min–1), assessed by incubation with L-[3H]-arginine, in both WKY (SED, 0.196 ± 0.054 compared with EX, 0.531 ± 0.052) and SHR (SED, 0.346 ± 0.076 compared with EX, 0.600 ± 0.049). Nitric oxide synthase (NOS) activity (pmol L-citrulline·(108 cells)–1), measured by the conversion of L-[3H]-arginine to L-[3H]-citrulline, was significantly increased in SHR/EX (0.072 ± 0.007) compared with SHR/SED (0.038 ± 0.007), but no changes were observed in WKY. The iNOS and eNOS protein levels assessed by Western blot were not affected by exercise. This upregulation of the platelet L-arginine–NO pathway may attenuate the risk of thromboembolic events, supporting the role of exercise in hypertension management.
UNDERGROUND LABORATORIES AND THEIR PHYSICS REACH
Authors: COCCIA E.
Published: March 2012

Underground laboratories, shielded by the Earth's crust from the particles that rain down on the surface in the form of cosmic rays, provide the low radioactive background environment necessary to host key experiments in the field of particle and astroparticle physics, nuclear astrophysics and other disciplines that can profit of their characteristics and of their infrastructures. The cosmic silence condition existing in these laboratories allows the search for extremely rare phenomena and the exploration of the highest energy scales that cannot be reached with accelerators. Major fundamental challenges are within the scope of these laboratories, notably, understanding the properties of neutrinos and dark matter, and exploring the unification of the fundamental forces of nature. I will review the physics reach and briefly describe the main underground facilities that are presently in operation around the world.
DOUBLE-LEPTON POLARIZATION ASYMMETRIES IN B → K1l+l- DECAY IN UNIVERSAL EXTRA DIMENSION
Authors: ŞIRVANLI B. B.
Published: March 2012

The double-lepton polarization asymmetries for the exclusive B → K1l+l- transition is studied in the universal extra dimension. It is shown that most of the double-lepton polarization asymmetries are sensitive to the model parameters. Any experimental measurements on double-lepton polarizations and their comparison with theoretical results can give valuable information on the physics beyond the standard model.
VEHICLE TYPE AND MAKE RECOGNITION BY COMBINED FEATURES AND ROTATION FOREST ENSEMBLE
Authors: ZHANG BAILING , ZHOU YIFAN
Published: March 2012

Vehicle type/make recognition based on images captured by surveillance cameras is a challenging task in intelligent transportation system and automatic surveillance. In this paper, we comparatively studied two feature extraction methods for image description, i.e. a new multiresolution analysis tool called Fast Discrete Curvelet Transform and the pyramid histogram of oriented gradients (PHOG). Curvelet Transform has better directional and edge representation abilities than widely used wavelet transform, which is particularly appropriate for the description of images rich with edges. PHOG represents the local shape by a histogram of edge orientations computed for each image sub-region, quantized into a number of bins, thus has the ascendency in its description of more discriminating information. A composite feature description from PHOG and Curvelet can further increase the accuracy of classification by taking their complementary information. We also investigated the applicability of the Rotation Forest (RF) ensemble method for vehicle classification based on the combined features. The RF ensemble contains a set of base multilayer perceptrons which are trained using principal component analysis to rotate the original axes of combined features of vehicle images. The class label is assigned by the ensemble via majority voting. Experimental results using more than 600 images from 21 makes of cars/vans show the effectiveness of the proposed approach. The composite feature is better than any single feature in the classification accuracy and the ensemble model produces better performance compared to any of the individual neural network base classifier. With a moderate ensemble size of 20, the Rotation Forest ensembles offers a classification rate close to 96.5%, exhibiting promising potentials for real-life applications.
RADICAL EXTRACTION USING AFFINE SPARSE MATRIX FACTORIZATION FOR PRINTED CHINESE CHARACTERS RECOGNITION
Authors: TAN JUN , XIE XIAOHUA , ZHENG WEI-SHI , LAI JIAN-HUANG
Published: March 2012

Each Chinese character is comprised of radicals, where a single character (compound character) contains one (or more than one) radicals. For human cognitive perspective, a Chinese character can be recognized by identifying its radicals and their spatial relationship. This human cognitive law may be followed in computer recognition. However, extracting Chinese character radicals automatically by computer is still an unsolved problem. In this paper, we propose using an improved sparse matrix factorization which integrates affine transformation, namely affine sparse matrix factorization (ASMF), for automatically extracting radicals from Chinese characters. Here the affine transformation is vitally important because it can address the poor-alignment problem of characters that may be caused by internal diversity of radicals and image segmentation. Consequently we develop a radical-based Chinese character recognition model. Because the number of radicals is much less than the number of Chinese characters, the radical-based recognition performs a far smaller category classification than the whole character-based recognition, resulting in a more robust recognition system. The experiments on standard Chinese character datasets show that the proposed method gets higher recognition rates than related Chinese character recognition methods.
IMPACT OF FULL RANK PRINCIPAL COMPONENT ANALYSIS ON CLASSIFICATION ALGORITHMS FOR FACE RECOGNITION
Authors: SONG FENGXI , YOU JANE , ZHANG DAVID , XU YONG
Published: March 2012

Full rank principal component analysis (FR-PCA) is a special form of principal component analysis (PCA) which retains all nonzero components of PCA. Generally speaking, it is hard to estimate how the accuracy of a classifier will change after data are compressed by PCA. However, this paper reveals an interesting fact that the transformation by FR-PCA does not change the accuracy of many well-known classification algorithms. It predicates that people can safely use FR-PCA as a preprocessing tool to compress high-dimensional data without deteriorating the accuracies of these classifiers. The main contribution of the paper is that it theoretically proves that the transformation by FR-PCA does not change accuracies of the k nearest neighbor, the minimum distance, support vector machine, large margin linear projection, and maximum scatter difference classifiers. In addition, through extensive experimental studies conducted on several benchmark face image databases, this paper demonstrates that FR-PCA can greatly promote the efficiencies of above-mentioned five classification algorithms in appearance-based face recognition.
STRANGENESS PRODUCTION AT FINITE TEMPERATURE AND BARYON DENSITY IN AN EFFECTIVE RELATIVISTIC MEAN FIELD MODEL
Authors: IAZZI F. , INTROZZI R. , LAVAGNO A. , PIGATO D. , YOUNIS M. H.
Published: March 2012

We study the strangeness production in hot and dense nuclear medium, by requiring the conservation of the baryon density, electric charge fraction and zero net strangeness. The hadronic equation of state is investigated by means of an effective relativistic mean field model, with the inclusion of the full octet of baryons and kaon mesons. Kaons are considered taking into account of an effective chemical potential depending on the self-consistent interaction between baryons. The obtained results are compared with a minimal coupling scheme, calculated for different values of the anti-kaon optical potential and with noninteracting kaon particles. In this context, we also consider the possible onset of the kaon condensation for a wide range of temperatures and baryon densities.
HIGHLY BRANCHED POLY(BUTYLENE ADIPATE) FOR PVC PLASTICIZATION: SYNTHESIS AND BLEND CHARACTERIZATION
Authors: ASCIONE L. , AMBROGI V. , PANNICO M. , CARFAGNA C. , PERSICO P.
Published: March 2012

New formulations of flexible poly(vinyl chloride) (PVC) were obtained by replacing low-molecular weight dioctylphtalate (DOP) with poly(butylene adipate)-based plasticizers, with both linear poly(butylene adipate) (PBA) and hyperbranched poly(butylene adipate) (HPBA). Thermal, physical, mechanical and thermo-mechanical properties of flexible PVC blends containing different percentages of polymeric plasticizers were compared. Experimental results demonstrated that the migration phenomenon could be overcome by using polymeric plasticizers, without compromising the mechanical properties of final products and improving their thermal stability.
A DIONE APPROACH TO MODIFY THE OPTICAL AND MESOPHASE PROPERTIES OF DISCOTIC TRIPHENYLENE DERIVATIVES
Authors: KONG XIANGFEI , HE ZHIQUN , XU MIN , LIANG CHUNJUN , JING XIPING
Published: March 2012

Two discotic liquid crystalline compounds, 6,7,10,11-tetra-pentyloxytriphenylene-1,4-dione and 6,7,10,11-tetra-heptyloxy- triphenylene-1,4-dione were synthesized and characterized. The synthesis consisted of two key steps: the preparation of 1,4-dimethoxy-6,7,10,11-tetra-alkoxytriphenylene and the oxidation to form the target compounds. In the latter step, the reaction was significantly improved using sodium nitrite in trifluoroacetic acid as an oxidant, resulting in an enhanced overall reaction yield and dramatically reduced reaction time. Both products show liquid crystalline phases, which were investigated using polarized optical microscopy and thermal analysis. The product with a longer side chain displayed a broader liquid crystal phase temperature range and favored a faster structure formation at low temperature. In addition to absorption at 272 nm, which is commonly observed in triphenylene-based discotic liquid crystals, the optical absorption of both compounds extends to the visible range, with extra absorption observed at 630 nm.
NOVEL COMPOSITE-BASED CATHODES FOR MOLTEN CARBONATE FUEL CELLS BY ELECTROCHEMICAL MULTICOMPONENT MODIFICATION
Authors: CHEN LI-JIANG , LIU HAI-HUA , DONG XIAO-LING , HONG XIAO-PING , JIA YAN-RONG , LIN CHANG-JIAN
Published: March 2012

A multicomponent modification on the surface of porous nickel with nanoparticles is conducted by an electrophoretic deposition (EPD) technique to prepare new composite-based cathodes for molten carbonate fuel cells (MCFCs). Two new ternary composite-based cathodes, (nano- LiCoO2-LiFeO2 )- Ni and (nano- LiCoO2-CeO2 )- Ni , are inclined to possess good morphology and homogeneous element distribution when prepared under moderate current density resulting from a medium deposition voltage and suspension pH value in this work. Both composite-based cathodes manifest excellent anti-deformation and anti-dissolution performances under conditions of a simulated MCFC startup stage and are thus expected to be useful for application in the MCFC industry.
LOW-TEMPERATURE HYDROGEN DESORPTION FROM LiBH4–TiF4 COMPOSITE
Authors: LIU YONGFENG , ZHOU HAI , DING YUFAN , GAO MINGXIA , PAN HONGGE
Published: March 2012

Approximately 6.3 wt.% of hydrogen is released from a LiBH4–0.25TiF4 combination below 150°C. Hydrogen desorption from the LiBH4–0.25TiF4 combination undergoes a quite different reaction process with respect to the LiBH4–0.33TiF3 mixture due to the higher oxidation state of Ti4+ and the lower mean bond cleavage energy of Ti–F bonds in TiF4 . This finding provides a viable approach for significantly decreasing the dehydrogenation temperature of LiBH4 by optimizing the additives with high oxidation valency.
FUNCTIONAL MESOPOROUS POLYMER MONOLITH FOR APPLICATION IN ION-EXCHANGE AND CATALYSIS
Authors: NANDI MAHASWETA , OKADA KEISUKE , UYAMA HIROSHI
Published: March 2012

Mesoporous polyacrylonitrile (PAN) monoliths have been prepared by thermally induced phase separation technique (TIPS) using the unique affinity of PAN towards a mixture of water/dimethyl sulphoxide (DMSO). The overall microstructure, porosity and skeleton size of the polymer monoliths are controlled by optimizing the concentration of the polymer, ratio of water and DMSO, and the cooling temperature. The monoliths have been functionalized by amidoximation of the –CN functional groups in methanolic hydroxyl amine. The amidoximated PAN monoliths can be used as efficient ion-exchangers for the separation of different metal ions. On the other hand, the copper(II)-exchanged amidoximated monolith can be used as catalyst for oxidation of cycloalkanes and toluene under liquid-phase condition using mild oxidizing agent, tert-butyl hydroperoxide (TBHP).
STRUCTURAL AND MARTENSITIC TRANSFORMATION OF BULK, DISORDERED AND NANOCRYSTALLINE Ni2MnGa ALLOYS
Authors: PERUMAN K. VALLAL , VINODH KUMAR S. , PUSHPANATHAN K. , MAHENDRAN M.
Published: March 2012

Ferromagnetic Ni2MnGa nanoparticles were prepared by post milling and annealing method. Differential scanning calorimetry studies confirm absence of martensitic and Curie transformation in the disordered state. It was found that the bulk alloy was annealed into a well-defined 7 M structure at around 1073 K. The residual stress of nanoparticles induced the disordered phase to transform into a NM tetragonal phase through atomic ordering. Thermo hysteresis curve of the 'disordered' powder was linear and revealed very low moment indicative of paramagnetic nature. It is confirmed that the martensitic transformation in nanosized particles is predominantly dependent on the strain and the particles size.
STRUCTURAL, OPTICAL AND ELECTRICAL PROPERTIES OF Al-DOPED ZnO TRANSPARENT CONDUCTING OXIDE FOR SOLAR CELL APPLICATIONS
Authors: CHER W. , YICK S. , XU S. , HAN Z. J. , OSTRIKOV K.
Published: March 2012

Al -doped zinc oxide (AZO) thin films are deposited onto glass substrates using radio-frequency reactive magnetron sputtering and the improvements in their physical properties by post-synthesis thermal treatment are reported. X-ray diffraction spectra show that the structure of films can be controlled by adjusting the annealing temperatures, with the best crystallinity obtained at 400°C under a nitrogen atmosphere. These films exhibit improved quality and better optical transmittance as indicated by the UV-Vis spectra. Furthermore, the sheet resistivity is found to decrease from 1.87 × 10-3 to 5.63 × 10-4Ω⋅cm and the carrier mobility increases from 6.47 to 13.43 cm2 ⋅ V-1 ⋅ s-1 at the optimal annealing temperature. Our results demonstrate a simple yet effective way in controlling the structural, optical and electrical properties of AZO thin films, which is important for solar cell applications.
Fabrication of Piezoelectric Polyurea Films by Alternating Deposition
Authors: Yanase Takashi , Hasegawa Tetsuya , Nagahama Taro , Shimada Toshihiro
Published: March 2012

We demonstrate that polyurea films can be prepared by alternating deposition with automated deposition control involving quartz crystal microbalance monitoring and optical source heating. The thickness of the films was linearly controlled by changing the repetition time of deposition, and the stoichiometry obtained was much higher than ±5%. The surface roughness of a 600-nm-thick film was 0.5 nm, which ensures the nm thickness control of the deposited polymers. The piezoelectricity of the films was confirmed by directly measuring the current transient induced by mechanical stress and by measuring the capacitance change induced by electric field.
Quenching Effect, Signal to Noise, Contrast to Noise Ratios on Scintillator Screens for Proton Beam Dosimetry System
Authors: Kim Seonkyu , Lee Se Byeong , Yoo Seung Hoon , Cho Sungkoo , Kim Dong Wook , Shin Dongho , Park Sung Yong , Kim Chan Hyeong , Lee Sang Hoon
Published: March 2012

There has been dosimetry using scintillator screen for proton quality assurance recently. To develop a proton beam dosimetry system using scintillator, we evaluated the dosimetric properties and imaging quality for three kinds of scintillator screens. Proton beam ranges of 6, 9, and 12 g/cm2 were determined in a water phantom using an ion chamber. Beam current was optimized about each scintillator screen at proton beam ranges of 6, 9, and 12 g/cm2. Dose rate was in beam condition of proton treatment. For comparison of the dosimetric properties, the quenching correction factors and standard deviations for the scintillator screens (C6H6, Gd2O2S:Tb, and Gd2O2S) were obtained using the relation between the light yield (scintillator-relative output) and the dose distribution (diode-relative output). The image qualities for the scintillator screens were compared, using the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR), in consideration of the physical properties of the scintillator materials. After correction of the quenching effect, the correction factor for scintillator screen Gd2O2S:Tb was the lowest, at 0.004 g/(cm2 MeV). The standard deviations of the difference between the yields measured by the scintillator screens and the diode detector averaged 1, 1.3, and 1.3, respectively, at all of the ranges from origin to the peak position. The dosimetric properties of scintillator screens were no large difference. The SNRs of the scintillator screens (C6H6, Gd2O2S:Tb, and Gd2O2S) averaged 28.67, 40.18, and 24.56, respectively, at all ranges. The CNRs of the scintillator screens (C6H6, Gd2O2S:Tb, and Gd2O2S) averaged 0.44, 0.33, and 0.42, respectively, at all ranges. The highest SNR and the lowest CNR of scintillator screen Gd2O2S:Tb were more excellent than those of the other scintillator screens. We evaluated the dosimetric properties in terms of the quenching-effect correction factors, standard deviations image qualities in terms of SNR and CNR about scintillator screens. The correction factor and standard deviation for scintillator screens made no large difference. Scintillator screen Gd2O2S:Tb had the highest value of SNR and the lowest value of CNR, and accordingly was considered to be best in proton beam imaging quality.
Calcium influx through a possible coupling of cation channels impacts skeletal muscle satellite cell activation in response to mechanical stretch
Authors: Hara Minako , Tabata Kuniko , Suzuki Takahiro , Do Mai-Khoi Q. , Mizunoya Wataru , Nakamura Mako , Nishimura Shotaro , Tabata Shoji , Ikeuchi Yoshihide , Sunagawa Kenji , Anderson Judy E. , Allen Ronald E. , Tatsumi Ryuichi
Published: March 2012

When skeletal muscle is stretched or injured, satellite cells, resident myogenic stem cells positioned beneath the basal lamina of mature muscle fibers, are activated to enter the cell cycle. This signaling pathway is a cascade of events including calcium-calmodulin formation, nitric oxide (NO) radical production by NO synthase, matrix metalloproteinase activation, release of hepatocyte growth factor (HGF) from the extracellular matrix, and presentation of HGF to the receptor c-met, as demonstrated by assays of primary cultures and in vivo experiments. Here, we add evidence that two ion channels, the mechanosensitive cation channel (MS channel) and the long-lasting-type voltage-gated calcium-ion channel (L-VGC channel), mediate the influx of extracellular calcium ions in response to cyclic stretch in satellite cell cultures. When applied to 1-h stretch cultures with individual inhibitors for MS and L-VGC channels (GsMTx-4 and nifedipine, respectively) or with a less specific inhibitor (gadolinium chloride, Gd), satellite cell activation and upstream HGF release were abolished, as revealed by bromodeoxyuridine-incorporation assays and Western blotting of conditioned media, respectively. The inhibition was dose dependent with a maximum at 0.1 μM (GsMTx-4), 10 μM (nifedipine), or 100 μM (Gd) and canceled by addition of HGF to the culture media; a potent inhibitor for transient-type VGC channels (NNC55–0396, 100 μM) did not show any significant inhibitory effect. The stretch response was also abolished when calcium-chelator EGTA (1.8 mM) was added to the medium, indicating the significance of extracellular free calcium ions in our present activation model. Finally, cation/calcium channel dependencies were further documented by calcium-imaging analyses on stretched cells; results clearly demonstrated that calcium ion influx was abolished by GsMTx-4, nifedipine, and EGTA. Therefore, these results provide an additional insight that calcium ions may flow in through L-VGC channels by possible coupling with adjacent MS channel gating that promotes the local depolarization of cell membranes to initiate the satellite cell activation cascade.
c-Jun/AP-1 is required for CCK-induced pancreatic acinar cell dedifferentiation and DNA synthesis in vitro
Authors: Guo Lili , Sans Maria Dolors , Hou Yanan , Ernst Stephen A. , Williams John A.
Published: March 2012

Endogenous CCK plays an important role in pancreatic regeneration after pancreatitis. We used primary culture of mouse pancreatic acinar cells to evaluate the effect of CCK on acinar cell morphology and gene expression and to determine signaling pathways required for proliferation of acinar cells in vitro. Over 4 days in culture, cells grew out from acini and formed patches of monolayer, which displayed a reduced expression of acinar cell markers including digestive enzymes and Mist1 and an increased expression of ductal and embryonic markers, including cytokeratin 7, β-catenin, E-cadherin, pdx-1, and nestin. There was no appearance of stellate cell markers. CCK enhanced cellular spreading, DNA synthesis, and cyclin D1 expression. When signaling pathways were evaluated, CCK stimulation increased c-Jun expression, JNK and ERK activity, and AP-1 activation. Chemical inhibitors of JNK and ERK pathways, dominant-negative JNK and c-Jun, and c-Jun shRNA significantly inhibited CCK-induced DNA synthesis, CCK-induced AP-1 activation, and cyclin D1 expression. Furthermore, dominant-negative c-Jun reduced the increased expression of β-catenin and the decreased expression of amylase during culture. These results show that MAPK/c-Jun/AP-1 pathway plays an important role in pancreatic acinar cell dedifferentiation and proliferation in culture. Monolayer culture can serve as a model to study acinar cell proliferation similar to regeneration after pancreatitis in vivo.
Effect of peripheral administration of cholecystokinin on food intake in apolipoprotein AIV knockout mice
Authors: Yoshimichi Go , Lo Chunmin C. , Tamashiro Kellie L. K. , Ma Liyun , Lee Dana M. , Begg Denovan P. , Liu Min , Sakai Randall R. , Woods Stephen C. , Yoshimatsu Hironobu , Tso Patrick
Published: March 2012

Apolipoprotein AIV (apo AIV) and cholecystokinin (CCK) are satiation factors secreted by the small intestine in response to lipid meals. Apo AIV and CCK-8 has an additive effect to suppress food intake relative to apo AIV or CCK-8 alone. In this study, we determined whether CCK-8 (1, 3, or 5 μg/kg ip) reduces food intake in fasted apo AIV knockout (KO) mice as effectively as in fasted wild-type (WT) mice. Food intake was monitored by the DietMax food system. Apo AIV KO mice had significantly reduced 30-min food intake following all doses of CCK-8, whereas WT mice had reduced food intake only at doses of 3 μg/kg and above. Post hoc analysis revealed that the reduction of 10-min and 30-min food intake elicited by each dose of CCK-8 was significantly larger in the apo AIV KO mice than in the WT mice. Peripheral CCK 1 receptor (CCK1R) gene expression (mRNA) in the duodenum and gallbladder of the fasted apo AIV KO mice was comparable to that in WT mice. In contrast, CCK1R mRNA in nodose ganglia of the apo AIV KO mice was upregulated relative to WT animals. Similarly, upregulated CCK1R gene expression was found in the brain stem of apo AIV KO mice by in situ hybridization. Although it is possible that the increased satiating potency of CCK in apo AIV KO mice is mediated by upregulation of CCK 1R in the nodose ganglia and nucleus tractus solitarius, additional experiments are required to confirm such a mechanism.
The transcription factor HNF-4α: a key factor of the intestinal uptake of fatty acids in mouse
Authors: Frochot Vincent , Alqub Malik , Cattin Anne-Laure , Carrière Véronique , Houllier Anne , Baraille Floriane , Barbot Laurence , Saint-Just Susan , Ribeiro Agnès , Lacasa Michel , Cardot Philippe , Chambaz Jean , Rousset Monique , Lacorte Jean-Marc
Published: March 2012

With an excessive postprandial accumulation of intestine-derived, triglyceride-rich lipoproteins being a risk factor of cardiovascular diseases, it is essential to characterize the mechanisms controlling the intestinal absorption of dietary lipids. Our aim was to investigate the role of the transcription factor hepatocyte nuclear factor (HNF)-4α in this process. We used transgenic mice with a specific and inducible intestinal knockout of Hnf-4α gene. One hour after a lipid bolus, in the presence of the lipase inhibitor tyloxapol, lower amounts of triglycerides were found in both plasma and intestinal epithelium of the intestine-specific Hnf-4α knockout (Hnf-4αintΔ) mice compared with the Hnf-4αloxP/loxPcontrol mice. These discrepancies were due to a net decrease of the intestinal uptake of fatty acid in Hnf-4αintΔmice compared with Hnf-4αloxP/loxPmice, as assessed by the amount of radioactivity that was recovered in intestine and plasma after gavage with labeled triolein or oleic acid, or in intestinal epithelial cells isolated from jejunum after a supply of labeled oleic acid-containing micelles. This decreased fatty acid uptake was associated with significant lower levels of the fatty acid transport protein-4 mRNA and protein along the intestinal tract and with a lower acyl-CoA synthetase activity in Hnf-4αintΔmice compared with the control mice. We conclude that the transcription factor HNF-4α is a key factor of the intestinal absorption of dietary lipids, which controls this process as early as in the initial step of fatty acid uptake by enterocytes.
Peroxisome proliferator-activated receptor-γ protects against vascular aging
Authors: Modrick Mary L. , Kinzenbaw Dale A. , Chu Yi , Sigmund Curt D. , Faraci Frank M.
Published: March 2012

Vascular disease occurs commonly during aging. Carotid artery and cerebrovascular disease are major causes of stroke and contributors to dementia. Recent evidence suggests that peroxisome proliferator-activated receptor-γ (PPARγ) may play a protective role in the vasculature, but the potential importance of PPARγ in vascular aging is unknown. To examine the hypothesis that PPARγ normally protects against vascular aging, we studied heterozygous knockin mice expressing a human dominant-negative mutation in PPARγ (P465L, designated L/+). Endothelial dysfunction, a major contributor to vascular disease, was studied using carotid arteries from adult (8 ± 1 mo) and old (24 ± 1 mo) L/+ mice and wild-type littermates. In arteries from wild-type mice, responses to the endothelium-dependent agonist ACh were similar in adult and old wild-type mice but were reduced by ∼50% in old L/+ mice ( n = 7–10, P < 0.05). Impaired responses in arteries from old L/+ mice were restored to normal by a scavenger of superoxide. Relaxation of arteries to nitroprusside (an NO donor) was similar in all groups. Contraction of arteries to U46619 was not affected by age or genotype, while maximal responses to endothelin-1 were reduced with age in both wild-type and L/+ mice. Vascular expression (mRNA) of the catalytic component of NADPH oxidase (Nox2) was not altered in wild-type mice but was increased significantly in old L/+ mice. These findings provide the first evidence that interference with PPARγ function accelerates vascular aging, suggesting a novel role for PPARγ in protecting against age-induced oxidative stress and endothelial dysfunction.
Activating autoantibodies to the angiotensin II type I receptor play an important role in mediating hypertension in response to adoptive transfer of CD4+ T lymphocytes from placental ischemic rats
Authors: Novotny Sarah Richards , Wallace Kedra , Heath Judith , Moseley Janae , Dhillon Pushpinder , Weimer Abram , Wallukat Gerd , Herse Florian , Wenzel Katrin , Martin James N. , Dechend Ralf , LaMarca Babbette
Published: March 2012

Hypertension in rats with chronic placental ischemia (reduced uterine perfusion pressure, RUPP) is associated with elevated inflammatory cytokines, agonistic autoantibodies to the angiotensin II type I receptor (AT1-AA) and CD4+ T cells; all of which are elevated in preclamptic women. Additionally, we have shown that adoptive transfer of RUPP CD4+ T cells increases blood pressure, inflammatory cytokines, and sFlt-1. The objective of this study was to determine the long-term effects of RUPP CD4+ T cells on AT1-AA, renal and systemic hemodynamics in pregnant rats. To answer this question CD4+ T splenocytes were magnetically isolated on day 19 of gestation from control RUPP and normal pregnant (NP) rats and injected into a new group of NP rats at day 13 of gestation. On day 19 of gestation mean arterial pressure (MAP) and renal function (glomerular filtration rates, GFR) were analyzed and serum collected for AT1-AA analysis. To determine a role for AT1-AA to mediate RUPP CD4+ T cell-induced blood pressure increases, MAP was analyzed in a second group of rats treated with AT1 receptor blockade losartan (10 mg·kg−1·day−1) and in a third group of rats treated with rituximab, a B cell-depleting agent (250 mg/kg) we have shown previously to decrease AT1-AA production in RUPP rats. MAP increased from 101 ± 2 mmHg NP to 126 ± 2 mmHg in RUPP rats ( P < 0.001) and to 123 ± 1 mmHg in NP rats injected with RUPP CD4+ T cells (NP+RUPP CD4+T cells) ( P < 0.001). Furthermore, GFR decreased from 2.2 ml/min ( n = 7) in NP rats to 1.0 ml/min ( n = 5) NP+RUPP CD4+T cell. Circulating AT1-AA increased from 0.22 ± 0.1 units in NP rats to 13 ± 0.7 ( P < 0.001) units in NP+RUPP CD4+T cell-treated rats but decreased to 8.34 ± 1 beats/min in NP+RUPP CD4+ T cells chronically treated with rituximab. Hypertension in NP+RUPP CD4+T cell group was attenuated by losartan (102 ± 4 mmHg) and with B cell depletion (101 ± 5 mmHg). Therefore, we conclude that one mechanism of hypertension in response to CD4+ T lymphocytes activated during placental ischemia is via AT1 receptor activation, potentially via AT1-AA during pregnancy.
Pathways of Ca2+ entry and cytoskeletal damage following eccentric contractions in mouse skeletal muscle
Authors: Zhang Bao-Ting , Whitehead Nicholas P. , Gervasio Othon L. , Reardon Trent F. , Vale Molly , Fatkin Diane , Dietrich Alexander , Yeung Ella W. , Allen David G.
Published: March 2012

Muscles that are stretched during contraction (eccentric contractions) show deficits in force production and a variety of structural changes, including loss of antibody staining of cytoskeletal proteins. Extracellular Ca2+ entry and activation of calpains have been proposed as mechanisms involved in these changes. The present study used isolated mouse extensor digitorum longus (EDL) muscles subjected to 10 eccentric contractions and monitored force production, immunostaining of cytoskeletal proteins, and resting stiffness. Possible pathways for Ca2+ entry were tested with streptomycin (200 μM), a blocker of stretch-activated channels, and with muscles from mice deficient in the transient receptor potential canonical 1 gene (TRPC1 KO), a candidate gene for stretch-activated channels. At 30 min after the eccentric contractions, the isometric force was decreased to 75 ± 3% of initial control and this force loss was reduced by streptomycin but not in the TRPC1 KO. Desmin, titin, and dystrophin all showed patchy loss of immunostaining 30 min after the eccentric contractions, which was substantially reduced by streptomycin and in the TRPC1 KO muscles. Muscles showed a reduction of resting stiffness following eccentric contractions, and this reduction was eliminated by streptomycin and absent in the TRPC1 KO muscles. Calpain activation was determined by the appearance of a lower molecular weight autolysis product and μ-calpain was activated at 30 min, whereas the muscle-specific calpain-3 was not. To test whether the loss of stiffness was caused by titin cleavage, protein gels were used but no significant titin cleavage was detected. These results suggest that Ca2+ entry following eccentric contractions is through a stretch-activated channel that is blocked by streptomycin and encoded or modulated by TRPC1.
Four weeks of normobaric “live high-train low” do not alter muscular or systemic capacity for maintaining pH and K+ homeostasis during intense exercise
Authors: Nordsborg N. B. , Siebenmann C. , Jacobs R. A. , Rasmussen P. , Diaz V. , Robach P. , Lundby C.
Published: March 2012

It was investigated if athletes subjected to 4 wk of living in normobaric hypoxia (3,000 m; 16 h/day) while training at 800–1,300 m [“live high-train low” (LHTL)] increase muscular and systemic capacity for maintaining pH and K+ homeostasis as well as intense exercise performance. The design was double-blind and placebo controlled. Mean power during 30-s all-out cycling was similar before and immediately after LHTL (650 ± 31 vs. 628 ± 32 W; n = 10) and placebo exposure (658 ± 22 vs. 660 ± 23 W; n = 6). Supporting the performance data, arterial plasma pH, lactate, and K+ during submaximal and maximal exercise were also unaffected by the intervention in both groups. In addition, muscle buffer capacity (in mmol H+·kg dry wt−1·pH−1) was similar before and after in both the LHTL (140 ± 12 vs. 140 ± 16) and placebo group (145 ± 2 vs. 140 ± 3). The expression of sarcolemmal H+ transporters (Na+/H+ exchanger 1, monocarboxylate transporters 1 and 4), as well as expression of Na+-K+ pump subunits-α1, -α2, and -β1 was also similar before and after the intervention. In conclusion, muscular and systemic capacity for maintaining pH and K+ balance during exercise is similar before and after 4 wk of placebo-controlled normobaric LHTL. In accordance, 30-s all-out sprint ability was similar before and after LHTL.