bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipid Class and Fatty Acid Content of the Leptocephalus Larva of Tropical Eels
Authors: Deibel D. , Parrish C. C. , Grønkjær P. , Munk P. , Nielsen T. Gissel
Published: April 2012

The leptocephalus larva of eels distinguishes the elopomorph fishes from all other bony fishes. The leptocephalus is long lived and increases in size primarily through the synthesis and deposition of glycosaminoglycans. Energy stored during the larval stage, in the form of glycosaminoglycan and lipids, is required to fuel migration, metamorphosis and metabolism of the subsequent glass eel stage. Despite the importance of energy storage by leptocephali for survival and recruitment, their diet, condition and lipid content and composition is essentially unknown. To gain further insight into energy storage and condition of leptocephali, we determined the lipid class and fatty acid concentration of larvae collected on a cross‐shelf transect off Broome, northwestern Australia. The total lipid concentration of two families and four sub‐families of leptocephali ranged from 2.7 to 7.0 mg g wet weight−1, at the low end of the few published values. Phospholipid and triacylglycerol made up ca. 63 % of the total lipid pool. The triacylglycerol:sterol ratio, an index of nutritional condition, ranged from 0.9 to 3.7, indicating that the leptocephali were in good condition. The predominant fatty acids were 16:0 (23 mol%), 22:6n‐3 (docosahexaenoic acid, DHA, 16 mol%), 18:0 (8.2 mol%), 20:5n‐3 (eicosapentaenoic acid, EPA, 6.7 mol%), 18:1n‐9 (6.4 mol%) and 16:1n‐7 (6.3 mol%). The DHA:EPA ratio ranged from 2.4 to 2.9, sufficient for normal growth and development of fish larvae generally. The leptocephali had proportions of bacterial markers >4.4 %, consistent with the possibility that they consume appendicularian houses or other marine snow that is bacteria rich.
2-D Velocity Structure in Kerala-Konkan Basin Using Traveltime Inversion of Seismic Data
Authors: Singh Praveen Kumar , Sain Kalachand
Published: April 2012

The existence of gas-hydrates in marine sediments increases the seismic velocity, whereas even a small amount of underlying free-gas reduces the velocity considerably. The change in velocities against the background (without gas-hydrates and free-gas) velocity can be used for identification and assessment of gas-hydrates. Traveltime inversion of identifiable reflections from large offset multi channel seismic (MCS) experiment is an effective method to derive the 2-D velocity structure in an area. We apply this method along a seismic line in the Kerala-Konkan (KK) offshore basin for delineating the gas-hydrates and free-gas bearing sediments across a bottom simulating reflector (BSR). The result reveals a four layer 2-D shallow velocity model with the topmost sedimentary layer having velocity of 1,680-1,740 m/s and thickness of 140-190 m. The velocity of the second layer of uniform thickness (110 m) varies from 1,890 to 1,950 m/s. The third layer, exhibiting higher velocity of 2,100-2,180 m/s, is interpreted as the gas-hydrates bearing sediment, the thickness of which is estimated as 100 to 150 m. The underlying sedimentary layer shows a reduction in seismic velocity between 1,620 to 1,720 m/s. This low-velocity layer with 160-200 m thickness may be due to the presence of free-gas below the gas-hydrates layer.
Parents and adolescents growing up in the digital age: Latent growth curve analysis of proactive media monitoring
Authors: Padilla‐Walker Laura M. , Coyne Sarah M. , Fraser Ashley M. , Dyer W. Justin , Yorgason Jeremy B.
Published: April 2012

The current study examined how parents' use of restrictive and active monitoring and deference changed over three years, and examined both adolescent and parent characteristics as predictors of initial levels of media monitoring, as well as change in media monitoring. Participants included 276 mother–child dyads (M age of child = 12.08, SD = .63, 50% female) taken from Time 2 of the Flourishing Families Project, 96% of whom had complete data for Time 4 (N = 266). Active monitoring was the most common approach at the first and second time points, while active monitoring and deference were equally common by the final time point. Latent growth curve analysis revealed that restrictive and active monitoring decreased over time, while deference increased. In addition, both adolescent and parent characteristics were predictive of initial levels of all three types of monitoring, and of change in restrictive monitoring. Discussion focuses on developmental implications of these findings.
Formation of MgF3−‐dependent complexes between an AAA+ ATPase and σ54
Authors: Zhang Nan , Buck Martin
Published: April 2012

The widely distributed bacterial σ54‐dependent transcription regulates pathogenicity and numerous adaptive responses in diverse bacteria. Formation of the σ54‐dependent open promoter complex is a multi‐step process driven by AAA+ ATPases. Non‐hydrolysable nucleotide analogues are particularly suitable for studying such complexity by capturing various intermediate states along the energy coupling pathway. Here we report a novel ATP analogue, ADP–MgF3−, which traps an AAA+ ATPase with its target σ54. The MgF3−‐dependent complex is highly homogeneous and functional assays suggest it may represent an early transcription intermediate state valuable for structural studies.
Effect of a yoga program on glucose metabolism and blood lipid levels in adolescent girls with polycystic ovary syndrome
Authors: Nidhi Ram , Padmalatha Venkatram , Nagarathna Raghuram , Ram Amritanshu
Published: April 2012

Objective

To assess the efficacy of yoga therapy on glucose metabolism and blood lipid values in adolescent girls with polycystic ovary syndrome (PCOS).

Methods

A prospective, randomized, interventional controlled trial recruited 90 adolescents aged between 15 and 18 years who met the Rotterdam criteria for PCOS. A yoga group practiced suryanamaskara, asanas, pranayama, and meditation 1 hour per day each day for12 weeks while another group practiced conventional physical exercises. The Mann–Whitney U test was used to compare score changes between the 2 groups.

Results

The changes in fasting insulin, fasting blood glucose, and homeostasis model assessment of insulin resistance were significantly different in the 2 groups (P < 0.05). Except for high‐density lipoprotein cholesterol, the changes in blood lipid values were also significantly different (P < 0.05). The changes in body mass index, waist circumference, hip circumference, and waist‐to‐hip ratio, however, were not significantly different (P > 0.05).

Conclusion

Yoga was found to be more effective than conventional physical exercises in improving glucose, lipid, and insulin values, including insulin resistance values, in adolescent girls with PCOS independent of anthropometric changes.

Central Trial Registry of India No.: REFCTRI‐2008 000291.
Factors associated with disclosure of HIV serostatus to sexual partners of patients receiving HIV care in Kabale, Uganda
Authors: Osinde Michael O. , Kakaire Othman , Kaye Dan K.
Published: April 2012

Objective

To evaluate factors independently associated with disclosure of HIV serostatus in the era of widespread access to antiretroviral agents (ARVs) among individuals receiving HIV care in Uganda.

Methods

Between January 1 and August 31, 2009, 403 HIV‐positive individuals attending Kabale Hospital in southwestern Uganda were interviewed about their sociodemographic characteristics; sexuality; contraceptive use and sexual behavior; and disclosure of HIV serostatus to sexual partners. Data regarding disclosure versus nondisclosure were analyzed to identify factors independently associated with disclosure of serostatus.

Results

The study participants were predominantly female (74.0%). In all, 82.5% of the patients were receiving ARVs. Disclosure of HIV serostatus to regular sexual partners was reported by 50.9% of the participants, while 49.1% had chosen not to disclose their serostatus. Factors independently associated with nondisclosure were marital status; current use of ARVs; having children who had died (from any cause); being sexually active in the previous 6 months; and the number of sexual partners during the previous 6 months (P < 0.05 for all associations). Fear of stigma was the main reason for nondisclosure of HIV serostatus.

Conclusion

Despite receiving treatment with ARVs, many of the study participants neither disclosed their own HIV serostatus nor knew the HIV serostatus of their sexual partners.
The effect of bladder fullness on evaluation of pelvic organ prolapse
Authors: Haya Nir , Segev Eran , Younes Grace , Goldschmidt Eyal , Auslender Ron , Abramov Yoram
Published: April 2012

Objective

To investigate the effect of bladder fullness on pelvic organ prolapse (POP) staging via the Pelvic Organ Prolapse Quantification System (POP‐Q).

Methods

Sixty women with advanced POP underwent pelvic examination with maximal Valsalva straining via POP‐Q with an empty bladder and after transcatheter bladder filling to maximum cystometric capacity, with simultaneous intra‐abdominal and intravesical pressure recordings. Main outcome measures included POP‐Q values and staging with full versus empty bladder.

Results

An empty bladder was associated with a significantly higher POP‐Q staging (median, 3 vs 2; P < 0.0001); and a lower location of points Ba (4.51 vs 1.37; P < 0.0001), Aa (2.58 vs 0.62; P < 0.0001), Bp (− 0.68 vs − 1.10; P = 0.01), Ap (0.83 vs − 1.27; P = 0.002), C (1.57 vs − 1.07; P < 0.0001), and D (0.14 vs − 2.77; P < 0.0001) compared with a full bladder. However, genital hiatus, perineal body, and total vaginal length values were not significantly affected by bladder fullness. No differences in intra‐abdominal or detrusor pressures were noted between empty and full bladder states.

Conclusion

POP‐Q assessment with a full bladder is associated with underestimation of POP severity. Therefore, bladder emptying should be a standard requirement for POP‐Q staging and reporting.
Diagram to map the locations of endometriosis
Authors: Lasmar Ricardo Bassil , Lasmar Bernardo Portugal , Pillar Claudia
Published: April 2012

Objective

To develop and test a visual map that corresponds practically and objectively to the anatomical areas affected by endometriosis.

Method

The study comprised 150 questionnaires concerning 10 clinical cases of endometriosis presented as a visual diagram that were distributed at 3 different scientific events, among 3 groups of 50 gynecologists. Data were analyzed to evaluate the diagram's ability to graphically represent the endometriosis sites.

Results

After presentation at the first event, the rate of correct answers on the site of endometriosis was 84.7%; at the second event, after modifications implemented after feedback from the first event, the rate of correct answers was 97.4%; and at the third event, when all suggestions and modifications had been made, the rate was 99.7%.

Conclusion

The diagram proposed to map the location of endometriosis lesions appears to be an adequate and effective instrument to represent the site of the disease, with correlation at almost 100%.
Postabortion contraceptive use and method continuation in India
Authors: Zavier A.J. Francis , Padmadas Sabu S.
Published: April 2012

Objective

To investigate the patterns and determinants of postabortion contraceptive use and the rates of method continuation in India.

Methods

Population‐level retrospective calendar data on 5135 married women who had their last abortion during the 60 months preceding the survey were drawn from 2005–2006 Indian National Family Health Surveys. Multinomial logistic regression was used to model the factors associated with postabortion method choices. Method discontinuation rates were estimated using proportional hazard models.

Results

Overall, 70.4% of women reported not using any method following abortion, and the levels varied considerably across states. Significant differences were observed in the type of method adopted by women living in large cities, small towns, and rural areas. Poor and socially excluded women were less likely to use any method after abortion, particularly modern reversible methods. Method discontinuation rates were considerably higher among socially disadvantaged groups.

Conclusion

Postabortion contraceptive adoption is exceptionally low in India. Reproductive health interventions should urgently consider implementing comprehensive postabortion care policies, integrating family planning with sexual and reproductive healthcare services, and in particular targeting women from disadvantaged communities.
EDITORIAL FOREWORD
Authors: Baron Beth , Pursley Sara
Published: April 2012

This issue opens with an article by a pioneering scholar of Ottoman economic history, the late Donald Quataert. In the summer of 2010, Quataert wrote to inquire whether IJMES would be interested in a piece he had recently written on a corrupt Ottoman official in the coal mining district of Ereğli. Because the manuscript was too long for IJMES, Quataert revised it during a holiday in the “spectacular” Eastern Sierras. He passed away from cancer in February 2011 before learning that his article had been accepted for publication. His wife, Jean Quataert, a professor of history at Binghamton University and a coeditor of the Journal of Women's History, suggested that we work with one of her husband's students, David Gutman, to respond to reviewers’ suggestions and prepare the piece for publication. The editors of IJMES thank Jean Quataert for giving us permission to publish the piece and David Gutman for stepping into his mentor's shoes—no small task—and serving as a second author. We are honored to be able to publish Donald Quataert's final project, “Coal Mines, the Palace, and Struggles over Power, Capital, and Justice in the Late Ottoman Empire,” as testimony to a lifetime of innovative scholarship. A richly documented microhistorical account based on nineteen witness testimonies, the article experiments with narrative and shows state–society interactions on the ground, including the processes through which subaltern complaints were received and managed by the central Ottoman state as well as the ways these processes may have begun to fracture in the late Hamidian era.
IRAQ: HISTORY, MEMORY, CULTURE
Authors: Zubaida Sami
Published: April 2012

There is a stock argument on whether Iraq is an “artificial” creation of colonial power or a “real” entity with historical and psychological depth and identity. It is a futile question because all nation–states, in one form or another, are historical creations. The processes of their creation are diverse and lead to different outcomes in the degree of coherence and permanence. Our thinking on the subject has been highly influenced by the seminal concepts advanced by Benedict Anderson on the “imagining” of the nation, which is, in turn, underlined by the socioeconomic processes of modernity. The state, often superimposed from above, is a principal actor in this process. Educational systems, tied to qualifications and employment, for instance, are powerful means of enforcing a unified national language and, in turn, the medium of literacy, the press and media, and the means of imagining the nation. The state makes the nation, more or less successfully. The intelligentsia are the cadres of these processes. They and the state class, with which they overlap, are subject to the vagaries of political conflicts and struggles and, in the case of Middle Eastern states, to the repression and violence of the state and militant sectors of the population. In the case of Iraq these troublesome manifestations are particularly evident. The books under review are concerned with these processes and in particular with the role of the ideological cadres and institutions in their unfolding.
Prenatal maternal infection, neurodevelopment and adult schizophrenia: a systematic review of population-based studies
Authors: Khandaker G. M. , Zimbron J. , Lewis G. , Jones P. B.
Published: April 2012

Background

Disruption of foetal development by prenatal maternal infection is consistent with a neurodevelopmental model of schizophrenia. Whether specific prenatal infections are involved, their timing and the mechanisms of any effect are all unknown. We addressed these questions through a systematic review of population-based studies.

Method

Electronic and manual searches and rigorous quality assessment yielded 21 studies that included an objective assessment of individual-level prenatal maternal infection and standardized psychotic diagnoses in adult offspring. Methodological differences between studies necessitated a descriptive review.

Results

Results for prenatal maternal non-specific bacterial, respiratory or genital and reproductive infection differed between studies, which reported up to a two- to fivefold increased risk of schizophrenia. Evidence for herpes simplex virus type 2 (HSV-2) andToxoplasma gondiiwas mixed; some studies reported up to a doubling of schizophrenia risk. Prenatal HSV-1 or cytomegalovirus (CMV) infections were not associated with increased risk. Exposure to influenza or other infections during early pregnancy may be more harmful than later exposure. Increased proinflammatory cytokines during pregnancy were also associated with risk. Prenatal infection was associated with structural and functional brain abnormalities relevant to schizophrenia.

Conclusions

Prenatal exposure to a range of infections and inflammatory responses may be associated with risk of adult schizophrenia. Larger samples, mediation and animal models should be used to investigate whether there is a ‘sensitive period’ during development, and the effects of prenatal infections on neurodevelopment. Inclusion of genetic and immunological information should help to elucidate to what extent genetic vulnerability to schizophrenia may be explained by vulnerability to infection.
Phonotactics as phonology: knowledge of a complex restriction in Dutch
Authors: Kager René , Pater Joe
Published: April 2012

The Dutch lexicon contains very few sequences of a long vowel followed by a consonant cluster whose second member is a non-coronal. We provide experimental evidence that Dutch speakers have implicit knowledge of this gap, which cannot be reduced to the probability of segmental sequences or to word-likeness as measured by neighbourhood density. The experiment also suggests that the ill-formedness of this sequence is mediated by syllable structure: it has a weaker effect on speakers' judgements when the last consonant begins a new syllable. We provide an account in terms of Hayes & Wilson's (2008) maximum entropy model of phonotactics, using constraints that go beyond the complexity permitted by their model of constraint induction.
Delta- and Gamma-Tocotrienols Induce Classical Ultrastructural Apoptotic Changes in Human T Lymphoblastic Leukemic Cells
Authors: Wong Rebecca S.Y. , Radhakrishnan Ammu K. , Ibrahim Tengku Azmi Tengku , Cheong Soon-Keng
Published: April 2012

Tocotrienols are isomers of the vitamin E family, which have been reported to exert cytotoxic effects in various cancer cells. Although there have been some reports on the effects of tocotrienols in leukemic cells, ultrastructural evidence of tocotrienol-induced apoptotic cell death in leukemic cells is lacking. The present study investigated the effects of three isomers of tocotrienols (alpha, delta, and gamma) on a human T lymphoblastic leukemic cell line (CEM-SS). Cell viability assays showed that all three isomers had cytotoxic effects (p < 0.05) on CEM-SS cells with delta-tocotrienol being the most potent. Transmission electron microscopy showed that the cytotoxic effects by delta- and gamma-tocotrienols were through the induction of an apoptotic pathway as demonstrated by the classical ultrastructural apoptotic changes characterized by peripheral nuclear chromatin condensation and nuclear fragmentation. These findings were confirmed biochemically by the demonstration of phosphatidylserine externalization via flow cytometry analysis. This is the first study showing classical ultrastructural apoptotic changes induced by delta- and gamma-tocotrienols in human T lymphoblastic leukemic cells.
Entwicklungsbeobachtung und -dokumentation mit der EBD 3 – 48 und der EBD 48 – 72
Authors: Schreyer-Mehlhop Ina , Petermann Franz , Petermann Ulrike , Koglin Ute
Published: April 2012

Mit der Entwicklungsbeobachtung und -dokumentation (EBD) liegt ein systematisches Verfahren vor, mit dessen Hilfe pädagogische Fachkräfte den Entwicklungsstand von Kindern zwischen 3 und 72 Monaten für die folgenden sechs Entwicklungsbereiche einschätzen können: Haltungs- und Bewegungssteuerung, Fein- und Visuomotorik, Sprache, Kognition, soziale und emotionale Entwicklung. Die Ergebnisse der vorliegenden Arbeit weisen auf eine hohe Akzeptanz der EBD bei den Fachkräften hin. Ferner konnten mit der EBD über verschiedene Altersstufen etwa zwischen 5 bis 10 % der Kinder als Risikokinder eingeschätzt werden und es wurde deutlich, dass eine niedrige Erziehungs- und Beziehungsqualität mit Entwicklungsauffälligkeiten der Kinder in Zusammenhang stand.
Lava accretion system around mid‐ocean ridges: Volcanic stratigraphy in the Wadi Fizh area, northern Oman ophiolite
Authors: Kusano Yuki , Adachi Yoshiko , Miyashita Sumio , Umino Susumu
Published: April 2012

Detailed lithological study combined with geochemical variations of lavas reveals the across‐axis accretionary process at Wadi Fizh in the northern Oman ophiolite. The >900 m thick V1 sequence is divided into the lower V1 (LV1), middle V1 (MV1) and upper V1 (UV1) sequence by 0.4 m and 0.8 m thick umbers at 410 mab (meters above the base of the extrusive rocks) and 670 mab, respectively. The lowest part of the LV1 (LV1a) consists of lobate sheet and pillow lava flows extruded on the relatively flat ridge crest. Elongate pillows at 230 mab are flows draping downslope from the ridge crest and characterize the lithofacies on the ridge flank. Just above a jasper layer at 270 mab, 130 m thick evolved lavas were transported from the crest and emplaced on the ridge flank (LV1b). Off‐axial accretionary processes recorded in the MV1 resulted in alternating flows of less evolved, depleted lava and evolved lava, suggesting that the MV1 off‐axial lava sequence comprises flows emanated from both on‐ and off‐axis source vents. The less evolved and depleted UV1 flows suggest independent sources distinct from the axial lavas. The Lasail Unit is regarded as a subunit of the V1 because it is comparable to the UV1 in the geological, petrological, and geochemical characteristics. The broad compositional range of the V1 sequence endorses a view that the Wadi Fizh area corresponds to a segment end of the Oman paleospreading system accompanied by off‐axis volcanism as in segment boundaries of the present East Pacific Rise.
Global maps of lunar neutron fluxes from the LEND instrument
Authors: Litvak M. L. , Mitrofanov I. G. , Sanin A. , Malakhov A. , Boynton W. V. , Chin G. , Droege G. , Evans L. G. , Garvin J. , Golovin D. V. , Harshman K. , McClanahan T. P. , Mokrousov M. I. , Mazarico E. , Milikh G. , Neumann G. , Sagdeev R. , Smith D. E. , Starr R. , Zuber M. T.
Published: April 2012

The latest neutron spectrometer measurements with the Lunar Exploration Neutron Detector (LEND) onboard the Lunar Reconnaissance Orbiter (LRO) are presented. It covers more than 1 year of mapping phase starting on 15 September 2009. In our analyses we have created global maps showing regional variations in the flux of thermal (energy range < 0.015 eV) and fast neutrons (>0.5 MeV), and compared these fluxes to variances in soil elemental composition, and with previous results obtained by the Lunar Prospector Neutron Spectrometer (LPNS). We also processed data from LEND collimated detectors and derived a value for the collimated signal of epithermal neutrons based on the comparative analysis with the LEND omnidirectional detectors. Finally, we have compared our final (after the data reduction) global epithermal neutron map with LPNS data.
On the distributions of seasonal river flows: Lognormal or power law?
Authors: Bowers M. C. , Tung W. W. , Gao J. B.
Published: April 2012

Distributional analysis of river discharge time series is an important task in many areas of hydrological engineering, including optimal design of water storage and drainage networks, management of extreme events, risk assessment for water supply, and environmental flow management, among many others. Having diverging moments, heavy‐tailed power law distributions have attracted widespread attention, especially for the modeling of the likelihood of extreme events such as floods and droughts. However, straightforward distributional analysis does not connect well with the complicated dynamics of river flows, including fractal and multifractal behavior, chaos‐like dynamics, and seasonality. To better reflect river flow dynamics, we propose to carry out distributional analysis of river flow time series according to three “flow seasons”: dry, wet, and transitional. We present a concrete statistical procedure to partition river flow data into three such seasons and fit data in these seasons using two types of distributions, power law and lognormal. The latter distribution is a salient property of the cascade multiplicative multifractal model, which is among the best models for turbulence and rainfall. We show that while both power law and lognormal distributions are relevant to dry seasons, river flow data in wet seasons are typically better fitted by lognormal distributions than by power law distributions.
Radial distributions of equatorial phase space density for outer radiation belt electrons
Authors: Turner D. L. , Angelopoulos V. , Shprits Y. , Kellerman A. , Cruce P. , Larson D.
Published: April 2012

We present the first direct observations of equatorial electron phase space density (PSD) as a function of the three adiabatic invariants throughout the outer radiation belt using data from the Solid State Telescopes on THEMIS‐D. We estimate errors in PSD that result from data fitting and uncertainty in the calculation of the second and third invariants based on performance‐weighted results from seven different magnetic field models. The PSD gradients beyond geosynchronous orbit (GEO) are energy dependent, revealing different source regions for the relativistic and non‐relativistic populations. Specifically, the PSD distribution of outer belt relativistic electrons is peaked near L* ≈ 5.5. These features are typical for the outer belt, based on a survey of a two‐month period from 01 Feb.–31 Mar. 2010. The results are consistent with previous studies, which were based on off‐equatorial observations, but remove the high uncertainties introduced from mapping by using truly equatorial measurements (i.e., within only a few degrees of the magnetic equator) and quantifying the error in PSD. The newly calibrated THEMIS‐SST dataset forms a powerful tool for exploration of the near‐Earth magnetosphere, especially when combined with the upcoming RBSP mission.
Surface charging, discharging and chemical modification at a sliding contact
Authors: Singh S. V. , Kusano Y. , Morgen P. , Michelsen P. K.
Published: April 2012

Electrostatic charging, discharging, and consequent surface modification induced by sliding dissimilar surfaces have been studied. The surface-charge related phenomena were monitored by using a home-built capacitive, non-contact electrical probe, and the surface chemistry was studied by X-ray photoelectron spectroscopy (XPS). The experiments were performed on the disk surface of a ball-on-rotating-disk apparatus; using a glass disk and a Teflon (polytetrafluoroethylene) ball arrangement, and a polyester disks and a diamondlike carbon (DLC) coated steel ball arrangement. The capacitive probe is designed to perform highly resolved measurements, which is sensitive to relative change in charge density on the probed surface. For glass and Teflon arrangement, electrical measurements show that the ball track acquires non-uniform charging. Here not only the increase in charge density, but interestingly, increase in number of highly charged regions on the ball track was resolved. Threefold increase in the number of such highly charged regions per cycle was detected immediately before the gas breakdown-like incidences compared to that of other charge/discharge incidences at a fixed disk rotation speed. We are also able to comment on the behavior and the charge decay time in the ambient air-like condition, once the sliding contact is discontinued. XPS analysis showed a marginal deoxidation effect on the polyester disks due to the charging and discharging of the surfaces. Moreover, these XPS results clearly indicate that the wear and friction (sliding without charging) on the surface can be discarded from inducing such a deoxidation effect.
The effect of continuous pore stratification on the acoustic absorption in open cell foams
Authors: Mahasaranon Sararat , Horoshenkov Kirill V. , Khan Amir , Benkreira Hadj
Published: April 2012

This work reports new data on the acoustical properties of open cell foam with pore stratification. The pore size distribution as a function of the sample depth is determined in the laboratory using methods of optical image analysis. It is shown that the pore size distribution in this class of materials changes gradually with the depth. It is also shown that the observed pore size distribution gradient is responsible for the air flow resistivity stratification, which is measured acoustically and non-acoustically. The acoustical absorption coefficient of the developed porous sample is measured using a standard laboratory method. A suitable theoretical model for the acoustical properties of porous media with pore size distribution is adopted. The measured data for open porosity, tortuosity, and standard deviation data are used together with this model to predict the observed acoustic absorption behavior of the developed material sample. The transfer matrix approach is used in the modeling process to account for the pore size stratification. This work suggests that it is possible to design and manufacture porous media with continuous pore size stratification, which can provide an improvement to conventional porous media with uniform pore size distribution in terms of the attained acoustic absorption coefficient.
Perpendicular magnetization in CoO (111) layers induced by exchange interaction with ferromagnetic Co and Ni60Cu40 nanoclusters
Authors: Le Roy D. , Morel R. , Brenac A. , Pouget S. , Notin L.
Published: April 2012

The magnetization reversal of ferromagnetic nanoparticles coupled by exchange with a CoO (111) thin film has been studied. The interfacial exchange interaction triggers the appearance of an out-of-plane magnetization in the CoO (111) film. Co and Ni60Cu40 particles were chosen, as they present an order of magnitude difference in the saturation magnetization and Curie temperatures that surround the Néel temperature of CoO. In both cases, the exchange coupling leads to an increase of the coercive field, up to 200% in Co particles, and small exchange bias of 100 Oe when the external magnetic field is applied in the CoO (111) plane. When the field is applied along the CoO [111] direction, an unexpected net magnetization of the CoO (111) layer is revealed. Interestingly, it scales with the particles magnetization. The results are explained in terms of a large interfacial interaction and an induced canting of the CoO spins in the close region of the interface. The large value of the CoO magnetization indicates that the canting settles over an extended thickness of at least 3.7 nm and 1.2 nm in the cases of Co and Ni60Cu40 particles, respectively, which is consistent with a compensated antiferromagnetic spins surface.
Transformation and clustering of defects induced by electron irradiation in barium hollandite ceramics for radioactive cesium storage: Electron paramagnetic resonance study
Authors: Aubin-Chevaldonnet V. , Gourier D. , Caurant D. , Costantini J.-M.
Published: April 2012

Barium hollandite-type ceramics have been envisaged for the immobilization of radioactive cesium. To evaluate their stability under irradiation, a hollandite ceramic of composition Ba1.16Al2.32Ti5.68O16 was irradiated with electrons at a temperature close to room temperature to simulate the effect of β- and γ-decays of cesium. Ti3+ and O2- paramagnetic defects induced by electron irradiation [V. Aubin-Chevaldonnet et al., J. Phys.: Condens. Matter 18, 4007 (2006)] were detected by electron paramagnetic resonance. As the temperature in the bulk of the hollandite waste form could reach 300 °C at the beginning of the storage, the thermal stability of these paramagnetic defects was also studied. Isothermal annealing treatments at 300 °C and isochronal annealing treatments between 50 °C and 800 °C show that the irradiation induced Ti3+ (E1 and E2 centers) and O2− (H centers) do not recombine. Instead, they partially transform during annealing, respectively, into titanyl TiO+ centers (E3 centers) at the grain surface and into paramagnetic clusters of O2− of less than 10 nm size (G2 centers), trapped in the bulk of the grains. These oxygen-rich aggregates could prefigure the formation of molecular oxygen observed in electron irradiated glasses.
The influence of large-scale structures on entrainment in a decelerating transient turbulent jet revealed by large eddy simulation
Authors: Hu Bing , Musculus Mark P. B. , Oefelein Joseph C.
Published: April 2012

To provide a better understanding of the fluid mechanical mechanisms governing entrainment in decelerating jets, we performed a large eddy simulation (LES) of a transient air jet. The ensemble-averaged LES calculations agree well with the available measurements of centerline velocity, and they reveal a region of increased entrainment that grows as it propagates downstream during deceleration. Within the temporal and spatial domains of the simulation, entrainment during deceleration temporarily increases by roughly a factor of two over that of the quasi-steady jet, and thereafter decays to a level lower than the quasi-steady jet. The LES results also provide large-structure flow details that lend insight into the effects of deceleration on entrainment. The simulations show greater growth and separation of large vortical structures during deceleration. Ambient fluid is engulfed into the gaps between the large-scale structures, causing large-scale indentations in the scalar jet boundary. The changes in the growth and separation of large structures during deceleration are attributed to changes in the production and convection of vorticity. Both the absolute and normalized scalar dissipation rates decrease during deceleration, implying that changes in small-scale mixing during deceleration do not play an important role in the increased entrainment. Hence, the simulations predict that entrainment in combustion devices may be controlled by manipulating the fuel-jet boundary conditions, which affect structures at large scales much more than at small scales.
Surface elasticity effect on the size-dependent elastic property of nanowires
Authors: Yao Haiyan , Yun Guohong , Bai Narsu , Li Jiangang
Published: April 2012

A modified core-shell (MC-S) model is proposed to investigate the effect of surface elasticity on the elastic properties of nanowires under bending and tension loading modes. The continuous exponential function based on bulk elasticity is applied to the surface region of nanowires to better describe the elasticity in the surface layer. Two parameters related to the surface, namely, the inhomogeneous degree constant α̃, and the transition region of this inhomogeneous state rs (i.e., surface layer thickness), are introduced for examining the size effects of the elastic modulus of the overall nanowires. A strong size dependence of elasticity is revealed under both bending and tension loads. Furthermore, the theoretical solution for an effective Young’s modulus with relevant experiments, as well as the results of a molecular statistical thermodynamics (MST) method for zinc oxide (ZnO) nanowires, and a molecular dynamics (MD) simulation for silicon (Si) nanowires, are compared. It is shown that the theoretical curves not only agree well with the experimental data, but also fit the computational results (MST or MD) approximately below 20 nm. As a result, our model can predict the behavior of surface elasticity, with respect to the lateral size of nanostructures at a relatively small scale, no matter how stiff or soft the surface of the nanomaterials.
The Lawn; Or on Becoming a Killer
Authors: Lulka David
Published: April 2012

Immanence has resurfaced as a topic of theoretical interest, as it is perceived to bear upon many current developments in society and nature. In this paper, I delve further into this concept by examining my personal relations with a lawn. In this telling, lawns are typified by immanence, whether that refers to the growth of vegetation, the prospering of animal life within, or the emerging human capacity to control nonhuman immanences. In particular, I examine my role in the death of a lizard and scrutinize the guidance that immanence, as a concept, provides in ethical dilemmas. Uncertainty about the lizard body and what it can do plays a central role in this consideration. Although immanence can provide only equivocal answers, it retains significance not simply because it designates an essential attribute but also because its material manifestations have a duration that places humans in a disposition of suspended animation.
On the Stability of Water Oxidation Catalysts: Challenges and Prospects
Authors: Izgorodin Alex , Winther-Jensen Orawan , MacFarlane Douglas R.
Published: April 2012

Future requirements for water splitting technologies need highly efficient water oxidation catalysts that are sufficiently stable for operation over many years. Recent research has achieved significant progress in improving the electro-catalytic activities of these catalysts. However, there has not been a strong research focus on their long-term mechanical and chemical stability, yet this is critical for commercial application. In this paper we discuss some of the chemical and thermodynamic challenges confronting this goal, as well as some of the strategies that are available to overcome them. The challenge becomes even greater in the area of photo-active electromaterials; fortunately some of the same strategies may allow progress in this area also.
Dialectical thinking and health behaviors: The effects of theory of planned behavior
Authors: Jiang Feng , Lu Su , Hou Yubo , Yue Xiaodong
Published: April 2012

The primary purpose of this study was to investigate whether the theory of planned behavior (TPB) mediated the relationship between dialectical thinking and health behaviors. A sample of 285 undergraduates was tested with a dialectical thinking styles scale, health promoting lifestyle profiles, and TPB questionnaires. Structural equation modeling was used for data analysis. Results indicated that all the three dimensions of thinking styles (belief in the connection, acceptance of change, and acceptance of contradiction) exerted significant effects on TPB constructs. Specifically, the connection and the change dimensions had positive effects on health behaviors mediated by TPB, whereas the contradiction dimension had a negative effect. Model 2 showed a satisfactory fit, demonstrating the influential pathways between dialectical thinking and health behaviors. Implications in issues of health promotion and future research are discussed.
Munc13-4 reconstitutes calcium-dependent SNARE-mediated membrane fusion
Authors: Boswell Kristin L. , James Declan J. , Esquibel Joseph M. , Bruinsma Stephen , Shirakawa Ryutaro , Horiuchi Hisanori , Martin Thomas F.J.
Published: April 2012

Munc13-4 is a widely expressed member of the CAPS/Munc13 protein family proposed to function in priming secretory granules for exocytosis. Munc13-4 contains N- and C-terminal C2 domains (C2A and C2B) predicted to bind Ca2+, but Ca2+-dependent regulation of Munc13-4 activity has not been described. The C2 domains bracket a predicted SNARE-binding domain, but whether Munc13-4 interacts with SNARE proteins is unknown. We report that Munc13-4 bound Ca2+ and restored Ca2+-dependent granule exocytosis to permeable cells (platelets, mast, and neuroendocrine cells) dependent on putative Ca2+-binding residues in C2A and C2B. Munc13-4 exhibited Ca2+-stimulated SNARE interactions dependent on C2A and Ca2+-dependent membrane binding dependent on C2B. In an apparent coupling of membrane and SNARE binding, Munc13-4 stimulated SNARE-dependent liposome fusion dependent on putative Ca2+-binding residues in both C2A and C2B domains. Munc13-4 is the first priming factor shown to promote Ca2+-dependent SNARE complex formation and SNARE-mediated liposome fusion. These properties of Munc13-4 suggest its function as a Ca2+ sensor at rate-limiting priming steps in granule exocytosis.
Drosophila chibby is required for basal body formation and ciliogenesis but not for Wg signaling
Authors: Enjolras Camille , Thomas Joëlle , Chhin Brigitte , Cortier Elisabeth , Duteyrat Jean-Luc , Soulavie Fabien , Kernan Maurice J. , Laurençon Anne , Durand Bénédicte
Published: April 2012

Centriole-to–basal body conversion, a complex process essential for ciliogenesis, involves the progressive addition of specific proteins to centrioles. CHIBBY (CBY) is a coiled-coil domain protein first described as interacting with β-catenin and involved in Wg-Int (WNT) signaling. We found that, in Drosophila melanogaster, CBY was exclusively expressed in cells that require functional basal bodies, i.e., sensory neurons and male germ cells. CBY was associated with the basal body transition zone (TZ) in these two cell types. Inactivation of cby led to defects in sensory transduction and in spermatogenesis. Loss of CBY resulted in altered ciliary trafficking into neuronal cilia, irregular deposition of proteins on spermatocyte basal bodies, and, consequently, distorted axonemal assembly. Importantly, cby1/1 flies did not show Wingless signaling defects. Hence, CBY is essential for normal basal body structure and function in Drosophila, potentially through effects on the TZ. The function of CBY in WNT signaling in vertebrates has either been acquired during vertebrate evolution or lost in Drosophila.
Trade Policy Reform, Productivity Growth and Welfare in South Korean Agriculture
Authors: Yoo Chun Kwon , Gopinath Munisamy , Kim Hanho
Published: April 2012

We examine the effects of multilateral trade reform on South Korean agriculture and its economy. We first measure agricultural total factor productivity (TFP) and its components (technological and technical efficiency change) by estimating a production function and stochastic frontier using data from Korean Statistical Information Service during 1970‐2009. We then examine the sources of South Korean agricultural TFP with an emphasis on trade openness, and agricultural research and extension. We find that TFP elasticity with respect to trade openness is significantly larger after 1994 relative to the pre‐reform period. Further, Korean farmers have passed on productivity gains from trade reform to consumers in the form of lower prices.
Lack of significant renal tubular injury despite acute kidney injury in acute decompensated heart failure
Authors: Dupont Matthias , Shrestha Kevin , Singh Dhssraj , Awad Adiveh , Kovach Cynthia , Scarcipino Mario , Maroo Anjli P. , Tang W.H. Wilson
Published: April 2012

Aims

Acute kidney injury (AKI) is a strong predictor of adverse events with an incompletely understood pathophysiology. Neutrophil gelatinase‐associated lipocalin (NGAL) is proposed as an early marker of renal tubular injury. Our aim is to determine whether AKI during treatment of acute decompensated heart failure (ADHF) is accompanied by renal tubular injury.

Methods and results

Urinary NGAL (uNGAL) and urinary creatinine (uCreat) levels were measured in 141 consecutive patients hospitalized for ADHF and followed for 180 days for death or re‐hospitalization. AKI was defined as a rise in serum creatinine ≥0.3 mg/dl in a 48 h period. Median uNGAL/uCreat levels on Day 1 (baseline) were similar between patients who did and did not develop AKI [22.8 (12.5–106.8) μg/g vs. 20.6 (12.4–52.0) μg/g, P = 0.55]. On Day 2 and beyond, the difference between the AKI and no AKI cohorts increased, but was only significant on Day 3 [36.2 (21.7–131.8) μg/g vs. 29.4 (11.4–54.6) μg/g, P = 0.02]. The area under the receiver operating characteristic curve for Day 2 uNGAL/uCreat (≥ or <32 µg/g) to predict AKI was 0.61. There was no difference in diuretic response between ‘uNGAL/uCreat + ’ (≥ 27 µg/g) and ‘uNGAL/uCreat–’ (<27 µg/g) patients. However ‘uNGAL/uCreat + ’ patients had more adverse events after 180 days (66% vs. 52%, P = 0.02).

Conclusions

In patients with ADHF who develop AKI following diuretic therapy, a minor rise in uNGAL precedes AKI. However, the degree of renal tubular insult was much lower than that observed in other forms of AKI.
Relationship between pump speed and exercise capacity during HeartMate II left ventricular assist device support: influence of residual left ventricular function
Authors: Noor Mumin R. , Bowles Christopher , Banner Nicholas R.
Published: April 2012

Aims

Patients treated with a Thoratec HeartMate II left ventricular assist device (LVAD) are supported at a fixed pump speed. It is uncertain whether pump speed has a significant effect on exercise capacity. We investigated the relationship between pump speed and exercise capacity and the influence of residual LV function

Methods and results

We exercised 30 patients 6 months after HeartMate II implantation at clinical pump speed (typically 9000 r.p.m.) and again at the lowest speed available (6000 r.p.m.). Overall, peak oxygen uptake (pkVO2) positively correlated with LV ejection fraction (LVEF) both at the clinical pump speed (r = 0.41, P = 0.03) and after pump speed reduction (r = 0.50, P = 0.01). We divided the patients into two groups; those with higher LVEF (LVEF ≥40%) and those with lower LVEF (LVEF <40%) at the time of exercise testing. The response to speed change was different between the two groups. In the higher LVEF group, the impact of LVAD pump speed reduction was minimal (pkVO2 21.4 ± 4.8 mL/kg/min vs. 20.8 ± 5.5 mL/kg/min, P = 0.38). In the lower LVEF group, the pkVO2 was lower at both speeds; 17.2 ± 5.3 and 14.7 ± 5.9 mL/kg/min, respectively. In the lower LVEF group, the pkVO2 decreased by 2.5 mL/kg/min (P = 0.02) with speed reduction.

Conclusions

HeartMate II patients with lower residual LV function had a lower pkVO2 and were more sensitive to pump speed reduction. This suggests that modulation of LVAD speed during exercise could be of benefit to this group of patients.