bluuebunny/crossref_metadata_2025 huggingface dataset:
Sexual quality of life for localized prostate cancer: a cross‐cultural study between Japanese and American men
Authors: Namiki Shunichi , Arai Yoichi
Published: February 2011

Introduction

Race and ethnicity are important factors in health‐related quality of life (QOL) because of racial differences in preferences for, and trust in, health systems. Such factors are likely to affect QOL and patient satisfaction with care.

Results

Using a self‐reported questionnaire, Japanese men with prostate cancer reported lower sexual function scores at baseline. In detail, Japanese men were more likely than American men to report poor sexual desire, poor erection ability, poor overall ability to function sexually, poor ability to attain orgasm, poor quality of erections, infrequency of erections, infrequency of morning erections, and intercourse in the previous 4 weeks. However, Japanese men were less likely than American men to be concerned about their sexual function. Two years after surgery, American patients were more likely than Japanese patients to regain their baseline sexual function. The use of phosphodiesterase‐5 (PDE‐5) inhibitors has been widely publicized as the solution to erectile dysfunction after prostate cancer treatment. Although PDE‐5 inhibitors have been available in Japan since 1999, it is striking that Japanese men with localized prostate cancer are much less likely (only 10%) to use PDE‐5 inhibitors than American men.

Conclusion

Japanese patients with localized prostate cancer report worse sexual function but are less concerned about their reduced function. In the absence of a biological explanation for such differences, however, we suspect that cultural differences may explain the differences between QOL survey results from Japanese or American men with prostate cancer.
Effects on markers of inflammation and endothelial cell function of threead libitumdiets differing in type and amount of fat and carbohydrate: a 6-month randomised study in obese individuals
Authors: Bladbjerg Else-Marie , Larsen Thomas M. , Due Anette , Stender Steen , Astrup Arne , Jespersen Jørgen
Published: February 2011

Diet is important for the prevention of CVD, and diets high in MUFA might be more cardioprotective than low-fat diets. We hypothesise that inflammation and endothelial cell function will be improved most favourably by a high-MUFA diet compared with a low-fat diet. This was tested in a parallel randomised intervention trial on overweight individuals (aged 28·2 (sd4·6) years) assigned to a diet moderate in the amount of fat (35–45% of energy; >20% of fat as MUFA; MUFA diet,n39), a low-fat (20–30% of energy) diet (LF diet,n43) or a control diet (35 % of energy as fat,n24) for 6 months after weight loss. Protein constituted 10–20 % of energy in all diets. Food was provided free of charge. Fasting blood samples were collected before and after the intervention and analysed for C-reactive protein (CRP), IL-6, intercellular adhesion molecule, von Willebrand factor (vWF) and tissue factor pathway inhibitor. vWF concentrations tended to fall on the LF diet (4·78 (sd16·44) %;P = 0·07). Concentrations of IL-6 were reduced by the MUFA (0·37 (sd0·74) pg/ml;P < 0·01) and LF (0·47 (sd0·69) pg/ml;P < 0·001) diets, and CRP was reduced on all diets (MUFA: 0·48 (sd1·93) mg/l (P < 0·01); LF: 1·46 (sd2·89) mg/l (P < 0·001); control: 1·20 (sd1·97) mg/l (P < 0·01)). No significant differences were observed between changes induced by the different diets. Our findings suggest that in overweight subjects after weight loss, the MUFA and LF diets have similar long-term effects on inflammation and endothelial cell function.
A protein-rich beverage consumed as a breakfast meal leads to weaker appetitive and dietary responses v. a protein-rich solid breakfast meal in adolescents
Authors: J. Leidy Heather , I. Bales-Voelker Louise , T. Harris Corey
Published: February 2011

The purpose of the present study was to determine whether a protein-rich beverage leads to a differential response in appetite, satiety and subsequent energy intake compared with an energy- and macronutrient-matched solid version in young people. A total of fifteen adolescents (eight girls and seven boys; age 14 (sem 1) years, BMI percentile 79 (sem 4) %) randomly completed two testing days that included protein-rich (PR) breakfast meals (38 % of energy as protein, 48 (sem 2) g/meal) provided as a solid (S) or beverage (B). Breakfast was 24 % of estimated daily energy needs (2146 (sem 96) kJ/meal). Perceived appetite and satiety responses were collected over 5 h followed by an ad libitum lunch buffet. The PR-S meal led to greater reductions in 4 h postprandial appetite ( − 6221 (sem 1171) mm × 240 min) v. the PR-B meal ( − 3570 (sem 957) mm × 240 min; P < 0·05). When examining the data according to hourly responses, the PR-S meal led to greater reductions in appetite during postprandial hours 2, 3 and 4 v. the PR-B meal (all comparisons, P < 0·05). No differences in postprandial hourly or total (4 h) fullness were observed following the PR-S v. PR-B meals. The PR-S meal led to approximately 480 kJ less energy consumed at the ad libitum lunch buffet (1418 (sem 222) kJ) v. the PR-B meal (1900 (sem 326) kJ; P < 0·05). These data indicate that, although the food form of the PR breakfast meals had little, if any, effect on satiety, the appetitive responses were diminished and the subsequent food intake was greater when protein was consumed as a beverage v. a solid meal.
Is the alpine divide becoming more permeable to biological invasions? – Insights on the invasion and establishment of the Walnut Husk Fly, Rhagoletis completa (Diptera: Tephritidae) in Switzerland
Authors: Aluja M. , Guillén L. , Rull J. , Höhn H. , Frey J. , Graf B. , Samietz J.
Published: February 2011

The Walnut Husk Fly, Rhagoletis completa Cresson (Diptera: Tephritidae), is native to North America (Midwestern US and north-eastern Mexico) and has invaded several European countries in the past decades by likely crossing the alpine divide separating most parts of Switzerland from Italy. Here, we determined its current distribution in Switzerland by sampling walnuts (Juglans regia L.) in ecologically and climatically distinct regions along potential invasion corridors. R. completa was found to be firmly established in most low altitude areas of Switzerland where walnuts thrive, but notably not a single parasitoid was recovered from any of the samples. Infested fruit was recovered in 42 of the 71 localities that were surveyed, with mean fruit infestation rate varying greatly among sites. The incidence of R. completa in Switzerland is closely related to meteorological mean spring temperature patterns influencing growing season length, but not to winter temperatures, reflecting survival potential during hibernation. Importantly, areas in which the fly is absent correspond with localities where the mean spring temperatures fall below 7°C. Historical data records show that the natural cold barrier around the Alpine divide in the central Swiss Alps corresponding to such minimal temperatures has shrunk significantly from a width of more than 40 km before 1990 to around 20 km after 2000. We hypothesize on possible invasion/expansion routes along alpine valleys, dwell on distribution patterns in relation to climate, and outline future research needs as the incursion of R. completa into Switzerland; and, more recently, other European countries, such as Germany, Austria, France and Slovenia, represent an example of alien species that settle first in the Mediterranean Basin and from there become invasive by crossing the Alps.
Negative Hedging: Performance-Sensitive Debt and CEOs’ Equity Incentives
Authors: Tchistyi Alexei , Yermack David , Yun Hayong
Published: February 2011

We examine the relation between chief executive officers’ equity incentives and their use of performance-sensitive debt contracts. These contracts require higher or lower interest payments when the borrower’s performance deteriorates or improves, thereby increasing expected costs of financial distress while making a firm riskier to the benefit of option holders. We find that managers whose compensation is more sensitive to stock volatility choose steeper and more convex performance pricing schedules, while those with high delta incentives choose flatter, less convex pricing schedules. Performance pricing contracts therefore seem to provide a channel for managers to increase firms’ financial risk to gain private benefits.
Liquidity Dynamics and Cross-Autocorrelations
Authors: Chordia Tarun , Sarkar Asani , Subrahmanyam Avanidhar
Published: February 2011

This paper examines the relation between information transmission and cross-autocorrelations. We present a simple model, where informed trading is transmitted from large to small stocks with a lag. In equilibrium, large stock illiquidity induced by informed trading portends stronger cross-autocorrelations. Empirically, we find that the lead-lag relation increases with lagged large stock illiquidity. Further, the lead from large stock order flows to small stock returns is stronger when large stock spreads are higher. In addition, this lead-lag relation is stronger before macro announcements (when information-based trading is more likely) and weaker afterward (when information asymmetries are lower).
On the flow of buoyant fluid injected into a confined, inclined aquifer
Authors: GUNN IAIN , WOODS ANDREW W.
Published: February 2011

We study the dispersal of a plume of incompressible buoyant fluid injected into a confined sloping aquifer which has an outflow at a single fault which may be up-dip (up-slope) or down-dip (down-slope) from the point of injection. We develop a long-time asymptotic solution for the motion of the injected fluid. We show that for the case in which the outflow fault is up-dip from the point of injection, there is a critical injection rate above which the injected fluid floods the full depth of the aquifer, and we show that for the case in which the outflow fault is down-dip from the point of injection, there is a critical injection rate below which all injected fluid initially flows up-dip. Our analysis leads to expressions for the lateral extent of the injected fluid as a function of time, and we consider the implications of the model for the dispersal of supercritical carbon dioxide injected into deep saline aquifers. The work also indicates that the geometry of the system may have a significant effect on (i) the total volume of carbon dioxide which it is possible to sequester in a faulted aquifer and (ii) the interpretation of the dispersed position of any injected tracers.
Intratympanic gentamicin in Ménière's disease: our experience
Authors: Delgado L Pérez , Rodrigo J Fraile , Peña P Astier
Published: February 2011

Aims:

To analyse intratympanic gentamicin injection as a treatment option in patients with monolateral Ménière's disease resistant to medical treatment.

Material and methods:

Longitudinal, prospective, descriptive study of response to gentamicin treatment in 71 patients diagnosed with Ménière's disease and treated medically for more than a year, unsuccessfully. American Academy of Otolaryngology-Head and Neck Surgery criteria were used for diagnosis and follow up.

Results:

Complete vertigo control was obtained in 65.6 per cent of patients, and complete or substantial control in 84.37 per cent. Thirteen patients (18.3 per cent) suffered significant hearing loss.

Conclusion:

This intratympanic gentamicin injection protocol enabled effective vertigo control in most patients, and represents a good alternative to more aggressive techniques for the treatment of Ménière's disease which does not respond to medical treatment.
Treatment and prevention of cryptosporidiosis: what options are there for a country like Zambia?
Authors: KELLY PAUL
Published: February 2011

Cryptosporidiosis is a major infection of humans, leading to diarrhoea and growth failure in children, diarrhoea and malnutrition in immunocompromised adults, and is associated with increased mortality in all age groups. Using the country of Zambia as an example, I review the possible approaches to treatment and prevention in a tropical setting. The current optimal therapy for cryptosporidiosis is nitazoxanide which works well in HIV uninfected children, but treatment in patients with HIV infection remains remarkably difficult. No single drug has demonstrated efficacy in a randomised trial. No vaccine is available, so the best option for prevention for the moment is filtration and clean storage of drinking water. This would be expected to reduce cryptosporidiosis dramatically, but this needs to be demonstrated directly. Water filtration would have the added benefit of protection against many other pathogens, but the paucity of alternative approaches highlights the need for a better understanding of this important human pathogen.
Impact of community-directed treatment on soil transmitted helminth infections in children aged 12 to 59 months in Mazabuka District, Zambia
Authors: HALWINDI HIKABASA , MAGNUSSEN PASCAL , SIZIYA SETER , HANDEMA RAY , MEYROWITSCH DAN W. , OLSEN ANNETTE
Published: February 2011

This study assessed the impact of adding community-directed treatment (ComDT) to the routine health facility (HF)-based treatment on prevalence and intensity of soil transmitted helminth (STH) infections among children aged 12 to 59 months. Repeated cross-sectional surveys were conducted among randomly selected children of this age group from the intervention area (HF+ComDT area) and the comparison area (HF area) at baseline (n=986), 12 months (n=796) and 18 months (n=788) follow-up. The prevalence of Ascaris lumbricoides was significantly higher in the HF+ComDT as compared to the HF area at baseline (P=0·048), but not at 12 and 18 months follow-up. At baseline the HF+ComDT area had significantly higher intensities of A. lumbricoides compared to the HF area (P<0·001), but not at 12 and 18 months follow-ups. Prevalence and intensity of hookworm did not differ significantly between treatment arms at any time. Analysis of trends showed a significant decrease in prevalence of A. lumbricoides and hookworm in the HF+ComDT area (P<0·001), of hookworm in the HF area (P<0·05), but not of A. lumbricoides in the HF area. It is concluded that the ComDT approach generally enhanced the treatment effect among under-five year children and that this alternative approach may also have advantages in other geographical settings.
An attempt to use ectoparasites as tags for habitat occupancy by small mammalian hosts in central Europe: effects of host gender, parasite taxon and season
Authors: KRASNOV BORIS R. , STANKO MICHAL , MORAND SERGE
Published: February 2011

Objective.We used data on fleas and gamasid mites parasitic on 8 species of small mammals to test whether (a) species composition of ectoparasite infracommunities may be used to predict host habitat occupancy and (b) the accuracy of this prediction differs between ectoparasite taxa, host genders and seasons.Methods.We used a Random Forests algorithm that is based on the methodology of classification trees.Results.The accuracy of prediction of habitat occupancy was relatively low and varied substantially among host species. The combined rate of the correct prediction of host habitat occupancy from data on ectoparasites was significantly higher than 50%, albeit being relatively low. The accuracy of prediction (a) did not differ between male and female hosts when it was based on species composition of fleas in summer or of mites in summer and winter, (b) was significantly higher in male hosts than in female hosts when the winter data on fleas were used and (c) was significantly higher for flea than mite assemblages. The effect of season was found in mites but not in fleas with the accuracy of prediction being significantly higher in summer than in winter assemblages.Conclusions.Ectoparasites appeared to be not especially useful as biological markers for distinguishing host populations in different habitats in temperate zones.
God and the ontological foundation of morality
Authors: MORRISTON WES
Published: February 2011

In recent years, William Lane Craig has vigorously championed a moral argument for God's existence. The backbone of Craig's argument is the claim that only God can provide a ‘sound foundation in reality’ for morality. The present article has three principal aims. The first is to interpret and clarify the account of the ontological foundation of morality proposed by Craig. The second is to press home an important objection to that account. The third is to expose the weakness of Craig's case for saying that without God morality would be groundless and illusory.
The research interview as a test: Alignment to boundary, topic, and interactional leeway in parental accounts of a child protection procedure
Authors: Slembrouck Stef
Published: February 2011

This article concentrates on how interviewees experience the context of semi-structured or open interviews as a “test,” both in terms of being an interviewee and in terms of the roles presupposed in what the interview is about. It invites a reflexive discourse-analytical turn in which we concentrate on the interactional negotiation of various aspects of the interview situation and the interview as an interactional accomplishment. The focus is on the implications for the status of the data that was subsequently obtained, with an eye to locating “the social forces that impress on the ethnographic locale” (Burawoy 1998:15). Insights obtained in this way are argued to bear directly on our understanding of the central research topic under investigation. The data used here have been drawn from a research project on social class and coding orientations in experiential accounts of child protection in Belgium/Flanders. The data base consists of interviews with parent clients. (Data histories, narrative, interview as test, social class, child protection, ethnographic reflexivity)
Chronotopes of story and storytelling event in interviews
Authors: Perrino Sabina
Published: February 2011

Narratives in interviews involve the alignment of twochronotopes(Bakhtin's term, literally ‘time-space’) or what has traditionally been termed the narrated and narrating events. While narrators are expected to separate the there-and-then narrated-event chronotope from the here-and-now narrating-event chronotope, tropic forms ofcoevalalignment exist that erase or blur the line between the two events, as if they were occurring in the same time and place. In this article I argue for the need to map these shifting alignments in interviews. This article begins with, but then moves beyond, the familiar case of the “historical present,” where narrators shift into using nonpast temporal deixis for past events. Drawing first on an oral narrative from Italy, I show how resources besides the historical present can produce similar alignment effects. In order to demonstrate more extreme forms of coeval alignment, I then compare these data with those from a Senegalese narrator in Dakar who transposes participants “into” his stories. Through this comparison I illustrate how cross-chronotope alignment reveals the way narrators manage the relationship between story and event in interviews. Mapping these shifting alignments can help illuminate the emergent relations between interviewer and interviewee and hence show how stories reflect and shape the interview context in which they occur. (Narrative, interview, chronotope, historical present, Italian, Senegal)*
‘No more Hoares to Paris’: British foreign policymaking and the Abyssinian Crisis, 1935
Authors: HOLT ANDREW
Published: February 2011

Italy's invasion of Abyssinia in October 1935 prompted a major European crisis. This article applies the main theories of foreign policy analysis to the British Government's handling of this crisis. It argues that bureaucratic politics existed, but had little impact on outcomes. Domestic politics had more influence, but did not provide detailed instructions on how to act. The perceptions of key actors, informed by reasoned judgement, determined this. Fears of the threat posed by rival states coalesced with concerns about Britain's own military weakness, leading decision-makers to emphasise the need to act in tandem with France. British policy was therefore motivated by the tension between the public's desire to see action against Italy and the Government's wish to minimise any breach with her allies. These findings highlight the weaknesses of the bureaucratic politics model and show how domestic politics can affect foreign policy outcomes. They also demonstrate the interaction between rational analysis defined in terms of reasoned judgement, and actors' perceptions. It is thus argued that benefits are to be gleaned from combining these theories.
A long-term serological survey on Aujeszky's disease virus infections in wild boar in East Germany
Authors: PANNWITZ G. , FREULING C. , DENZIN N. , SCHAARSCHMIDT U. , NIEPER H. , HLINAK A. , BURKHARDT S. , KLOPRIES M. , DEDEK J. , HOFFMANN L. , KRAMER M. , SELHORST T. , CONRATHS F. J. , METTENLEITER T. , MÜLLER T.
Published: February 2011

Between 1985 and 2008, a total of 102 387 wild boar sera originating from Eastern Germany covering an area of 108 589 km2 were tested for the presence of Aujeszky's disease virus (ADV)-specific antibodies. From 1985 until 1991 and from 1992 until 2008, wild boar sera were exclusively investigated using either conventional seroneutralization assays (n=39 621) or commercial gB and full antigen ELISAs (n=62 766), respectively. Spatial-temporal analysis revealed an increasing ADV seroprevalence from 0·4% to 15·9%, on average, during the 24-year observation period that went along with a continuous spread of the infection in a western direction. During 2006 and 2008, 18% of the 66 affected districts had ADV seroprevalences >30%. There was a significant correlation between ADV seroprevalence and the hunting index of population density (HIPD) of wild boar in the entire study area, although this did not hold true for some regions. Seroprevalences did not differ between sexes but were age-dependent. East Germany has been officially free of Aujeszky's disease (pseudorabies) in domestic pigs since 1985. Although a risk for domestic pigs cannot be completely ruled out, experience has shown that ADV in domestic pigs could be eliminated although the virus was present in the wild boar population. Despite increasing ADV seroprevalence in the East German wild boar population no spillover infections from wild boar to domestic pigs have been reported. To further trace ADV infections in the wild boar population in Germany, a nationwide serological monitoring programme should be implemented.
Sugden's Critique of the Capability Approach
Authors: QIZILBASH MOZAFFAR
Published: February 2011

In comparing Sen's work with Mill's, Sugden criticizes Sen's capability approach because it may be applied in such a way that society or theorists judge what is best for people and potentially restrict liberty on that basis. Sugden cites Nussbaum's work as evidence in making his case. Sugden's critique of Sen's approach succeeds on a narrow reading of it. On that reading Sen is also critical of it because it does not leave enough room for liberty. On a broad reading, the critique has less force. Nussbaum's approach follows Mill in allowing people freedom to act on whatever desires they have if this does not harm others. This neutralizes the central element of Sugden's critique as it applies to her approach to some degree. Both Sen and Nussbaum nonetheless recognize the danger of illiberal restrictions in application which motivates Sugden's critique.
Autonomy and Adaptive Preferences
Authors: COLBURN BEN
Published: February 2011

Adaptive preference formation is the unconscious altering of our preferences in light of the options we have available. Jon Elster has argued that this is bad because it undermines our autonomy. I agree, but think that Elster's explanation of why is lacking. So, I draw on a richer account of autonomy to give the following answer. Preferences formed through adaptation are characterized by covert influence (that is, explanations of which an agent herself is necessarily unaware), and covert influence undermines our autonomy because it undermines the extent to which an agent's preferences are ones that she has decided upon for herself. This answer fills the lacuna in Elster's argument. It also allows us to draw a principled distinction between adaptive preference formation and the closely related – but potentially autonomy-enhancing – phenomenon of character planning.
Intuitions and the Demands of Consequentialism
Authors: TEDESCO MATTHEW
Published: February 2011

One response to the demandingness objection is that it begs the question against consequentialism by assuming a moral distinction between what a theory requires and what it permits. According to the consequentialist, this distinction stands in need of defense. However, this response may also beg the question, this time at the methodological level, regarding the credibility of the intuitions underlying the objection. The success of the consequentialist's response thus turns on the role we assign to intuitions in our moral methodology. After presenting the demandingness objection to consequentialism and revealing the underlying methodological stalemate, I break the stalemate by appealing to research in the cognitive neuroscience of intuitions. Given the evidence for the hypothesis that our moral intuitions are fundamentally emotional (rather than rational) responses, we should give our intuitions a modest (rather than robust) role in our moral methodology. This rescues the consequentialist's response to the demandingness objection.
In Defence of the Priority View: A Response to Otsuka and Voorhoeve
Authors: CRISP ROGER
Published: February 2011

In a recent article, Michael Otsuka and Alex Voorhoeve present an argument against the so-called ‘Priority View’ of distribution. According to that view, as stated by Derek Parfit, ‘benefiting people matters more the worse off these people are’, by virtue of the fact that a person's utility has ‘diminishing marginal moral importance’ the better off she is. Otsuka and Voorhoeve claim that, because this view fails to reflect a significant difference between the intrapersonal and the interpersonal, it should be rejected.
FIRST AND SECOND TRIMESTER SONOGRAPHIC SCREENING FOR FETAL DOWN SYNDROME
Authors: UNTERSCHEIDER JULIA , MALONE FERGAL D
Published: February 2011

Screening for Down syndrome is an important part of routine antenatal care and should be made available, if requested, after appropriate counselling including risks and benefits, to all pregnant women, regardless of maternal age. Prenatal screening for fetal Down syndrome and other aneuploidies has advanced significantly since its advent in the 1980s. Historically, women 35 years or older were offered prenatal genetic counselling and the option of a diagnostic test such as chorionic villus sampling or amniocentesis. With this screening approach only 20% to 30% of the fetal Down syndrome population are detected antenatally. Sonographic and maternal biochemical markers are now used in combination to screen for aneuploidies in the first and second trimesters. The most common screening method in the first trimester combines the maternal serum markers HCG and PAPP-A with the sonographic evaluation of fetal nuchal translucency thickness. Newer markers have been proposed to further refine the risk assessment for Down syndrome to maximise detection rates and minimise false positive rates. These newer first trimester markers include sonographic assessment of the fetal nasal bone (NB), the frontomaxillary facial (FMF) angle, ductus venosus (DV) Doppler and tricuspid valve regurgitation (TR).
Improving the Quality of Cognitive Behaviour Therapy Case Conceptualization: The Role of Self-Practice/Self-Reflection
Authors: Haarhoff Beverly , Gibson Kerry , Flett Ross
Published: February 2011

Background: CBT case conceptualization is considered to be a key competency. Prior to the publication in 2009 of Kuyken, Padesky and Dudley's book, little has been documented concerning methods for training conceptualization skills and the conceptualization process is usually perceived as predominantly an intellectual process. In this paper, the Declarative-Procedural-Reflective model of therapist skill acquisition provides a route to understanding how different kinds of knowledge systems can be integrated to enhance therapist skill acquisition. Method: Sixteen recent graduates of a postgraduate diploma in cognitive behaviour therapy worked independently through a self-practice/self-reflection workbook designed to lead them through a series of CBT interventions commonly used to elicit the information required for a CBT conceptualization. Results: The participants’ self-reflections were thematically analyzed and uncovered the following inter-related themes: increased theoretical understanding of the CBT model, self-awareness, empathy, conceptualization of the therapeutic relationship, and adaptation of clinical interventions and practice. Conclusions: A tentative conclusion reached, based on the self-reflections of the participants, was that targeted self-practice/self-reflection enhanced case conceptualization skill by consolidating the Declarative, Procedural and Reflective systems important in therapist skill acquisition.
Vertical stratification of microbial communities in the Red Sea revealed by 16S rDNA pyrosequencing
Authors: Qian Pei-Yuan , Wang Yong , Lee On On , Lau Stanley C K , Yang Jiangke , Lafi Feras F , Al-Suwailem Abdulaziz , Wong Tim Y H
Published: February 2011

Correction to: The ISME Journal(2011) 5, 507–518; doi:10.1038/ismej.2010.112; published online 29 July 2010 Owing to a typesetting error, the third sentence of the abstract was published incorrectly. The correct sentence is shown below: Significant differences in both bacterial and archaeal diversity were observed in the upper (20 and 50 m) and deeper layers (200 and 1500 m).
Stimuli-responsive star polymers through thiol–yne core functionalization/crosslinking of block copolymer micelles
Authors: Brummelhuis Niels ten , Schlaad Helmut
Published: February 2011

Thiol–yne photochemistry is applied in a convenient non-“click” fashion to produce well-defined functional star polymers in water.
Tunnel coupled dangling bond structures on hydrogen terminated silicon surfaces
Authors: Pitters Jason L. , Livadaru Lucian , Haider M. Baseer , Wolkow Robert A.
Published: February 2011

We study both experimentally and theoretically the electronic behavior of dangling bonds (DBs) at a hydrogen terminated Si(100)-2×1 surface. Dangling bonds behave as quantum dots and, depending on their separation, can be tunnel coupled with each other or completely isolated. On n-type highly doped silicon, the latter have a net charge of −1e, while coupled DBs exhibit altered but predictable filling behavior derived from an interplay between interdot tunneling and Coulomb repulsion. We found good correlation between many scanning tunneling micrographs of dangling bond structures and our theoretical results of a corresponding extended Hubbard model. We also demonstrated chemical methods to prevent tunnel coupling and isolate charge on a single dangling bond.
Minority electron mobilities in GaAs, In0.53Ga0.47As, and GaAs0.50Sb0.50 calculated within an ensemble Monte Carlo model
Authors: Tea E. , Aniel F.
Published: February 2011

The minority electron transport is crucial for the performances of heterojunction bipolar transistors (HBTs). Among the III-V semiconductors family, GaAsSb exhibits several advantages making it a serious candidate for the new generation of high speed HBTs. However, this alloy suffers from a lack of experimental studies. Properties such as electronic structure and charge carrier mobilities are of prime importance in theoretical device operation calculations. In this article, we investigate the minority electron mobilities by means of an ensemble Monte Carlo modeling including polar optical phonon–plasmon coupling through a self-consistent dielectric function. Realistic electronic structures are provided by a nonlocal empirical pseudopotential method. It is found that GaAs0.50Sb0.50 does not show a mobility enhancement for very high acceptor doping levels unlike GaAs and Ga0.47In0.53As.
Interactions among baroclinically-generated vortex rings in building up an acting spike to a bow shock layer
Authors: Kim Jae-Hyung , Matsuda Atsushi , Sasoh Akihiro
Published: February 2011

Vortex rings with a constant circulation are repetitively generated by depositing laser pulse energies ahead of a bow shock wave over a 20-mm diameter, flat-head cylinder in Mach 1.94 flow. Each vortex ring is formed after baroclinic interaction between a laser-heated gas and the bow shock wave. With increasing the pulse repetition frequency, f0, mutual interactions among the vortex rings become stronger; alternate pitching motions at f0=10–20 kHz and “slip-through” motions at f0=30 kHz appear. Beyond that, a quasisteady-state acting spike which decreases the stagnation pressure is built up.
The distributions of chain lengths in a crosslinked polyisoprene network
Authors: Hanson David E.
Published: February 2011

A fundament of classical rubber elasticity theory is the Gaussian chain approximation formula, P(n,r) for the probability distribution of end-to-end distances of a polymer chain composed of n beads. It is considered to provide a realistic distribution of end-to-end distances, r, provided that the length of the polymer chain is much greater than its average end-to-end distance. By considering the number of beads (n) to be the independent variable, we can use P(n,r) to construct the probability distributions of network chain lengths, for fixed r. Since the network crosslinks reduce the probability for the occurrence of longer chains, the formula must be modified by a correction factor that takes this effect into account. We find that, both the shape of the n-probability distribution, its height, and the position of the peak vary significantly with r. We provide a numerical procedure for constructing networks that respect these distributions. The algorithm was implemented in a three-dimensional, random polymer-and-node network model to construct polyisoprene networks at two common crosslink densities. Although the procedure does not constrain the density, we find that the networks constructed have densities very close to the measured bulk density.
Density functional theory and Raman spectroscopy applied to structure and vibrational mode analysis of 1,1′,3,3′-tetraethyl-5,5′,6,6′-tetrachloro- benzimidazolocarbocyanine iodide and its aggregate
Authors: Aydin Metin , Dede Özge , Akins Daniel L.
Published: February 2011

We have measured electronic and Raman scattering spectra of 1,1′,3,3′-tetraethyl-5,5′,6,6′-tetrachloro-benzimidazolocarbocyanine iodide (TTBC) in various environments, and we have calculated the ground state geometric and spectroscopic properties of the TTBC cation in the gas and solution phases (e.g., bond distances, bond angles, charge distributions, and Raman vibrational frequencies) using density functional theory. Our structure calculations have shown that the ground state equilibrium structure of a cis-conformer lies ∼200 cm−1 above that of a trans-conformer and both conformers have C2 symmetry. Calculated electronic transitions indicate that the difference between the first transitions of the two conformers is about 130 cm−1. Raman spectral assignments of monomeric- and aggregated-TTBC cations have been aided by density functional calculations at the same level of the theory. Vibrational mode analyses of the calculated Raman spectra reveal that the observed Raman bands above 700 cm−1 are mainly associated with the in-plane deformation of the benzimidazolo moieties, while bands below 700 cm−1 are associated with out-of-plane deformations of the benzimidazolo moieties. We have also found that for the nonresonance excited experimental Raman spectrum of aggregated-TTBC cation, the Raman bands in the higher-frequency region are enhanced compared with those in the nonresonance spectrum of the monomeric cation. For the experimental Raman spectrum of the aggregate under resonance excitation, however, we find new Raman features below 600 cm−1, in addition to a significantly enhanced Raman peak at 671 cm−1 that are associated with out-of-plane distortions. Also, time-dependent density functional theory calculations suggest that the experimentally observed electronic transition at ∼515 nm (i.e., 2.41 eV) in the absorption spectrum of the monomeric-TTBC cation predominantly results from the π → π* transition. Calculations are further interpreted as indicating that the observed shoulder in the absorption spectrum of TTBC in methanol at 494 nm (i.e., 2.51 eV) likely results from the ν″ = 0 → ν′ = 1 transition and is not due to another electronic transition of the trans-conformer—despite the fact that measured and calculated NMR results (not provided here) support the prospect that the shoulder might be attributable to the 0−0 band of the cis-conformer.
Renewable energy liberation by nonthermal intermolecular bond dissociation in water and ethanol
Authors: Graneau N. , Verdoold S. , Oudakker G. , Yurteri C. U. , Marijnissen J. C. M.
Published: February 2011

Prior indication that renewable energy can be extracted from hydrogen bonds in water has led to several investigations of the energy balance when bulk liquid is converted into micron scale droplets by directional (nonthermal) forces. The demonstration of this effect has previously involved pulsed high current arcs in water which produce large electrodynamic forces. Here, we show that renewable energy is also liberated during the creation of droplets by electrostatic forces in electrohydrodynamic atomization (electrospray) experiments. Using both ethanol and water, the energy outputs, primarily the droplet kinetic energy, were always greater than the energy inputs, implying that stored energy was liberated from the liquid. The energetics of generic chemical bonding are investigated to demonstrate that although this discovery was not publicly anticipated, it is consistent with conventional theory. This experimental breakthrough should have a major impact on the quest for renewable energy sources, capable of powering electricity generators.
Imaging dissipation and hot spots in carbon nanotube network transistors
Authors: Estrada David , Pop Eric
Published: February 2011

We use infrared thermometry of carbon nanotube network (CNN) transistors and find the formation of distinct hot spots during operation. However, the average CNN temperature at breakdown is significantly lower than expected from the breakdown of individual nanotubes, suggesting extremely high regions of power dissipation at the CNN junctions. Statistical analysis and comparison with a thermal model allow the estimate of an upper limit for the average tube-tube junction thermal resistance, ∼4.4×1011 K/W (thermal conductance of ∼2.27 pW/K). These results indicate that nanotube junctions have a much greater impact on CNN transport, dissipation, and reliability than extrinsic factors such as low substrate thermal conductivity.
Electron band alignment at the interface of (100)GaSb with molecular-beam deposited Al2O3
Authors: Afanas’ev V. V. , Chou H.-Y. , Stesmans A. , Merckling C. , Sun X.
Published: February 2011

From internal photoemission and photoconductivity measurements at the (100)GaSb/Al2O3 interface, the semiconductor valence band is found to be 3.05±0.10 eV below the oxide conduction band. This band alignment corresponds to conduction and valence band offsets of 2.3±0.10 and 3.05±0.15 eV, respectively. These results indicate that the valence band in GaSb lies energetically well above the valence band in InxGa1−xAs (0≤x≤0.53) or InP, suggesting the possibility of fabrication of hole quantum-well channel structures.
Simulations of the spectrum from a photoionized Si plasma
Authors: Lihua Bao , Zeqing Wu , Bin Duan , Yongkun Ding , Jun Yan
Published: February 2011

In order to interpret the spectrum of a photoionized Si plasma, we calculate the level populations and emissions using a collisional-radiative equilibrium model with detailed atomic data. In our calculations, levels with principal quantum number up to 9 are included and the electron impact processes are also taken into account. The peak around 1855 eV, which is not reproduced in the previous simulation, is obvious in the present results. Spectra analyzing shows that this peak mainly comes from the intercombination line of He-like Si. Our calculations indicate that the electron impact processes enhance this intercombination line about once, although the electron temperature is pretty low.
Ab initio potential energy surface and quantum dynamics for the H + CH4 → H2 + CH3 reaction
Authors: Zhou Yong , Fu Bina , Wang Chunrui , Collins Michael A. , Zhang Dong H.
Published: February 2011

A new full-dimensional potential energy surface for the title reaction has been constructed using the modified Shepard interpolation scheme. Energies and derivatives were calculated using the UCCSD(T) method with aug-cc-pVTZ and 6-311++G(3df,2pd) basis sets, respectively. A total number of 30 000 data points were selected from a huge number of molecular configurations sampled by trajectory method. Quantum dynamical calculations showed that the potential energy surface is well converged for the number of data points for collision energy up to 2.5 eV. Total reaction probabilities and integral cross sections were calculated on the present surface, as well as on the ZBB3 and EG-2008 surfaces for the title reaction. Satisfactory agreements were achieved between the present and the ZBB3 potential energy surfaces, indicating we are approaching the final stage to obtain a global potential energy surface of quantitative accuracy for this benchmark polyatomic system. Our calculations also showed that the EG-2008 surface is less accurate than the present and ZBB3 surfaces, particularly in high energy region.
Metallic surfaces as alignment layers for nondisplay applications of liquid crystals
Authors: Garbovskiy Yu. , Reisman L. , Celinski Z. , Camley R. E. , Glushchenko A.
Published: February 2011

Nearly all liquid crystal devices use a rubbed organic layer as a method of orienting the liquid crystals. This letter studies the alignment of nematic liquid crystals by rubbed and nonrubbed metallic surfaces. For rubbed metallic films, a homogeneous planar alignment of liquid crystals is found. Nonrubbed metallic surfaces align liquid crystals nonuniformly and randomly. The alignment produced by a single rubbed metallic surface extends from 10 to 50 μm and is stable in time. These results are important because they show that the organic layer may be eliminated for some applications, including tunable microwave and infrared signal processing elements.
Enhanced multiferroic properties of single-phase BiFeO3 bulk ceramics by Ho doping
Authors: Jeon Nari , Rout Dibyaranjan , Kim Ill Won , Kang Suk-Joong L.
Published: February 2011

Dense single-phase BiFeO3 and Bi0.9Ho0.1FeO3 ceramics were prepared by the solid-state reaction method. With Ho doping, the remnant polarization of BiFeO3 was enhanced and the switching characteristics improved at low electric fields. Ho doping increased the breakdown voltage with a reduction of the leakage current while mitigating the remnant polarization at high electric fields. These results can explain conflicting findings regarding the effects of rare-earth doping on remnant polarization. Bi0.9Ho0.1FeO3 exhibited peculiar double hysteresis looplike magnetization-magnetic field curves with a much enhanced remnant magnetization. These improved properties obtained by Ho doping demonstrate the possibility of enhancing the multiferroic applicability of BiFeO3.
Grain boundary assisted degradation and breakdown study in cerium oxide gate dielectric using scanning tunneling microscopy
Authors: Shubhakar K. , Pey K. L. , Kushvaha S. S. , O’Shea S. J. , Raghavan N. , Bosman M. , Kouda M. , Kakushima K. , Iwai H.
Published: February 2011

The presence of grain boundaries (GBs) in polycrystalline high-κ (HK) gate dielectric materials affects the electrical performance and reliability of advanced HK based metal-oxide-semiconductor devices. It is important to study the role of GB in stress-induced-leakage current (SILC) degradation and time-dependent dielectric breakdown of polycrystalline HK gate stacks. In this work, we present nanoscale localized electrical study and uniform stressing analysis comparing the electrical conduction properties at grain and GB locations for blanket cerium oxide (CeO2)-based HK thin films using scanning tunneling microscopy. The results clearly reveal higher SILC degradation rate at GB sites and their vulnerability to early percolation, supporting the phenomenon of GB-assisted HK gate dielectric degradation and breakdown.
Two-dimensional viscous flow simulation of a shock accelerated heavy gas cylinder
Authors: Shankar Santhosh K. , Kawai Soshi , Lele Sanjiva K.
Published: February 2011

Numerical simulation of Richtmyer–Meshkov instability (RMI) is conducted using an improved localized artificial diffusivity (LAD) method, which is used to treat discontinuities in the form of material interfaces and shocks in the flow-field. The RMI occurs on a cylindrical interface between air and SF6 accelerated by a Mach 1.2 shock initially in air. Navier–Stokes simulation is conducted to accurately predict the mixing between the two fluids. The initial conditions for the two-dimensional simulations are matched to previous experimental work by C. Tomkins et al. [“An experimental investigation of mixing mechanisms in shock-accelerated flow,” J. Fluid Mech. 611, 131 (2008)] and good agreement is found between the experimental data and numerical results. The study on initial condition sensitivity indicates that the initial pressure and density gradient are critical parameters that determine the primary vortex generation responsible for the flow development. A grid convergence study is carried out and the relative contribution of the artificial properties introduced by the LAD method is characterized. Novel to this study is the exploration of the effect of the third species (acetone used as a tracer particle in the experiments to obtain contour fields using planar laser induced florescence). The effect of the presence of the third species on the evolution of the RMI and mixing is shown to be non-negligible and an estimate of the amount of the tracer species that was present in the initial experimental set-up is given.
Fabrication of uniform Ge-nanocrystals embedded in amorphous SiO2 films using Ge-ion implantation and neutron irradiation methods
Authors: Chen Q. , Lu T. , Xu M. , Meng C. , Hu Y. , Sun K. , Shlimak I.
Published: February 2011

Uniform Ge-nanocrystals (Ge-ncs) embedded in amorphous SiO2 film were formed by using G74e+ ion implantation and neutron transmutation doping (NTD) method. Both experimental and theoretical results indicate that the existence of As dopants transmuted from G74e by NTD tunes the already stabilized (crystallized) system back to a metastable state and then activates the mass transfer processes during the transition form this metastable state back to the stable (crystallized) state, and hence the nanocrystal size uniformity and higher volume density of Ge-ncs. This method has the potential to open a route in the three-dimensional nanofabrication.
Pyroelectric control of the superprism effect in a lithium niobate photonic crystal in slow light configuration
Authors: Bernal M.-P. , Amet J. , Safioui J. , Devaux F. , Chauvet M. , Salvi J. , Baida F. I.
Published: February 2011

In this letter, tunability of the beam deviation on a two dimensional lithium niobate photonic crystal superprism is experimentally demonstrated thanks to the pyroelectric effect. Since the superprism geometry has been designed in a slow light configuration, the observed pyroelectric beam steering tunability is considerably enhanced. A beam deviation of 3.4°/°C has been experimentally measured for a working wavelength of 1565 nm. Direct applications can be found as ultracompact highly effective temperature variation sensors.