bluuebunny/crossref_metadata_2025 huggingface dataset:
Lustration after totalitarianism: Poland’s attempt to reconcile with its Communist past
Authors: Killingsworth Matt
Published: August 2010

The former Communist countries in Central and Eastern Europe have attempted to reconcile their Communist past in different ways. It is in Poland, however, where the issue of dealing with its Communist past through attempts at lustration has been especially fraught. It will be argued here that Poland’s lustration problems are caused primarily by a failure to understand the specific nature of totalitarian dictatorship that existed in Poland under Communist rule.
Preliminary small mammal taphonomy of FLK NW level 20 (Olduvai Gorge, Tanzania)
Authors: Arcos Saleta , Sevilla Paloma , Fernández-Jalvo Yolanda
Published: August 2010

The Bed-I series of Olduvai Gorge (Tanzania) is a reference site in human evolution, having yielded the holotypes ofParanthropus boiseiandHomo habilis, together with manufactured artefacts and abundant large and micro-fauna. Excavations in Olduvai Gorge have been recently resumed, with new aims and new results. This paper presents the results of the taphonomic analysis carried out on a fossil small-mammal assemblage recovered from FLK NW level 20, a layer overlying Tuff C, dated from 1.84 Ma. The analysis provides good evidence of a category 1 predator, most likely a barn owl, as the predator of the bone assemblage. Trampling and sediment compression might influence postdepositional breakage of the bones. This study is especially relevant since previous taphonomic analyses carried out at levels above and below this sample led to inconclusive results due to a low number of fossils (Fernández-Jalvo et al., 1998). The new sample provides new information to reconstruct the paleoenvironmental context in which early hominins inhabited.
Gray identities, canonical connection and integrability
Authors: Di Scala Antonio J. , Vezzoni Luigi
Published: August 2010

We characterize quasi-Kähler manifolds whose curvature tensor associated to the canonical Hermitian connection satisfies the first Bianchi identity. This condition is related to the third Gray identity and in the almost-Kähler case implies the integrability. Our main tool is the existence of generalized holomorphic frames previously introduced by the second author. By using such frames we also give a simpler and shorter proof of a theorem of Goldberg. Furthermore, we study almost-Hermitian structures having the curvature tensor associated to the canonical Hermitian connection equal to zero. We show some explicit examples of quasi-Kähler structures on the Iwasawa manifold having the Hermitian curvature vanishing and the Riemann curvature tensor satisfying the second Gray identity.
Pollen-mediated transgene flow in maize grown in the Huang-huai-hai region in China
Authors: ZHANG K. , LI Y. , LIAN L.
Published: August 2010

In order to study pollen-mediated gene flow in transgenic maize (Zea mays L.) in the Huang-huai-hai region of China, field trials were conducted in Jinan, Shandong Province in 2006 and 2007. The frequencies of gene flow from the donor plots, planted with transgenic maize as a pollen source, to the receptor plots, planted with non-transgenic maize, under different temporal or spatial separations were evaluated. The results showed that the frequency of pollen-mediated gene flow of the als gene from transgenic maize to non-transgenic maize decreased significantly with increasing distance. No gene flow was detected at 300 m. At a distance of 30 m, delaying the planting date of the transgenic maize by 1 week decreased the frequency of gene flow by 70%. A delay of 2 weeks decreased the gene flow frequency by more than 90%, while no gene flow was seen when the sowing date was delayed by 3 weeks. The results suggest that an appropriate isolation distance of 300 m or a temporal separation of 3 weeks could prevent gene flow from transgenic maize to non-transgenic maize in the Huang-huai-hai region.
Seasonality in the Cross Section of Stock Returns: The International Evidence
Authors: Heston Steven L. , Sadka Ronnie
Published: August 2010

This paper studies seasonal predictability in the cross section of international stock returns. Stocks that outperform the domestic market in a particular month continue to outperform the domestic market in that same calendar month for up to 5 years. The pattern appears in Canada, Japan, and 12 European countries. Global trading strategies based on seasonal predictability outperform similar nonseasonal strategies by over 1% per month. Abnormal seasonal returns remain after controlling for size, beta, and value, using global or local risk factors. In addition, the strategies are not highly correlated across countries. This suggests they do not reflect return premiums for systematic global risk.
What Drove the Increase in Idiosyncratic Volatility during the Internet Boom?
Authors: Fink Jason , Fink Kristin E. , Grullon Gustavo , Weston James P.
Published: August 2010

Aggregate idiosyncratic volatility spiked nearly fivefold during the Internet boom of the late 1990s, dwarfing in magnitude a moderately increasing trend. While some researchers argue that this rise in idiosyncratic risk was the result of changes in the characteristics of public firms, others argue that it was driven by the changing sentiment of irrational traders. We present evidence that the marketwide decline in maturity of the typical public firm can explain most of the increase in firm-specific risk during the Internet boom. Controlling for firm maturity, we find no evidence that investor sentiment drives idiosyncratic risk throughout the Internet boom.
Variation in the helminth community structure of three sympatric sigmodontine rodents from the coastal Atlantic Forest of Rio de Janeiro, Brazil
Authors: Simões R.O. , Souza J.G.R. , Maldonado A. , Luque J.L.
Published: August 2010

One hundred and eighty specimens of sigmodontine rodents living in sympatric conditions were collected in the Atlantic Forest in the state of Rio de Janeiro, Brazil (25Akodon cursor, 98Akodon montensisand 57Oligoryzomys nigripes) to examine whether the helminth structure and component communities can be characterized among these three closely related rodents. The parasite species richness was 9 inA. cursor, 12 inA. montensisand 12 inO. nigripes. Five species were common to the three rodent species, and eight were common toA. cursorandA. montensis. The trichostrongylids –Stilestrongylus etainA. cursor,S. aculeatainA. montensisandS. lanfrediaeinO. nigripes– were the species with highest dominance frequency and determined the characterization of individual community structures. The prevalence and abundance of concurrent helminth species among rodents were significantly different. Canonical multivariate analysis demonstrated a similar helminth community structure betweenA. cursorandA. montensisbut a high discrepancy betweenAkodonspp.and O. nigripes. Thus, the data indicated that small rodents such asA. cursor,A. montenisandO. nigripesthat are sympatric and phylogenetically related have a different community structure, but similar component community, suggesting the role of helminth specificity and the hosts' habitats as determinants in structuring their helminth communities.
The Changing Role of the Popular Religion ofNuo(傩) in Modern Chinese Politics
Authors: LI LAN
Published: August 2010

Since the early 1980s, China's rapid economic growth and profound social transformation have greatly changed the role of popular religion in modern Chinese politics. In the case ofnuo, these changes have been directly responsible for the incorporation of this popular religion into the implementation of Party-state's policy on ethnic minority and the provision of evidence to support the legitimacy of the Chinese Communist Party's regime. Through manipulation and reinterpretation by local governments, the popular religion ofnuohas not only become the target of local socio-economic development, a common phenomenon in contemporary China, but has also played a key role in ethnic identification, which is an important step for a post-Mao's CCP to maintain political stability in ethnic minority areas. In addition,nuohas through the research of Marxism-influenced schools fundamentally altered its position from an officially unrecognized religion opposed to both socialist political order and atheist ideology to a politically favoured ‘living fossil’1of primitive culture. This proves the Marxist evolutionary theory in which socialism and communism are thought to be inescapable consequences of social development. The positive role played bynuoin modern Chinese politics has brought the popular religion much open support and endorsement from party-state officials at all levels, including top-ranking officials within the Central Committee of the CCP. Like any popular religion,nuohas over the centuries undergone significant changes, but never before has it experienced such dramatic changes in its relationship with an anti-religious and pragmatic central government, something which has significantly altered the course of its development.
Kinematic calibration of the 3-DOF parallel module of a 5-axis hybrid milling machine
Authors: Wang Li-Ping , Xie Fu-Gui , Liu Xin-Jun , Wang Jinsong
Published: August 2010

This paper investigates the kinematic calibration of a 3-DOF parallel mechanism based on the minimal linear combinations of error parameters. The error mapping function between the geometric errors and the output errors is formulated and the identification matrix is generated and simplified. In order to identify the combinations of error parameters, four theorems to analyze the columns of the simplified identification matrix are introduced. Then, an anti-disturbance index is presented to evaluate the identification performance. On the basis of this index, measurement strategy is developed and optimal measuring configurations are given. After external calibration, linear interpolation compensation is applied to improve the terminal accuracy further. Results of experiment show that the method used in this paper is effective and efficient, and the errors are convergent within two iterations generally. This method can be extended to other parallel mechanisms with weakly nonlinear kinematics.
Fault detection and isolation in cooperative mobile robots using multilayer architecture and dynamic observers
Authors: Carrasco R. A. , Núñez F. , Cipriano A.
Published: August 2010

Mobile robot systems are being used more often in tasks that protect human operators from dangerous environments, but these benefits can be easily lost if the robots spend much of their time being repaired. This implies that any increment in their reliability will also improve their benefits. One way to achieve this is by adding redundant elements to the robot, but this adds complexity and cost to the design. On the other hand, cooperative mobile robots formed by members with the same basic structure provide a natural redundancy of elements, which may be used for reliability improvement. This work presents an architecture that takes advantage of the analytical and sensor redundancy present in groups of cooperative mobile robots in order to increase the reliability of the whole system. First, the design of the architecture is portrayed and the faults to be detected are described. The different layers of the system are then explained and analyzed using several simulations to test their capabilities and limitations. Finally, the experimental results on a group of small mobile robots are shown, validating the results delivered by simulations. These results show that the proposed architecture is able to detect and isolate correctly most of the faults tested.
Land-use changes as a critical factor for long-term wild rabbit conservation in the Iberian Peninsula
Authors: DELIBES-MATEOS MIGUEL , FARFÁN MIGUEL ÁNGEL , OLIVERO JESÚS , VARGAS JUAN MARIO
Published: August 2010

European rabbits (Oryctolagus cuniculus), a multifunctional keystone species in the Iberian Peninsula, have drastically declined over past decades. Rabbit decline has been frequently attributed to the arrival of two viral diseases. However, decline was apparently ongoing before the arrival of the diseases, as a consequence of habitat loss and fragmentation. In this paper, the effect on rabbit populations of land-use changes during recent decades in Andalusia (southern Spain) is analysed. Areas favourable for rabbits both at present and during the 1960s are identified, and the environmental and land-use factors that determine these areas established. In areas where the favourability for rabbits has changed during recent decades, main land use changes are assessed to identify possible factors explaining rabbit favourability in these areas. Areas favourable to rabbits are currently determined by factors similar to those during the 1960s; these areas have undergone geographic changes in recent decades, apparently as a consequence of land-use changes in Andalusia. The percentages of the variables that were positively associated with rabbit favourability in both models (current and 1960s) have declined in Andalusia as a whole, and in areas where rabbit favourability has decreased; hence environments suitable for rabbits have become impoverished. Conversely, in both models, environments suitable for rabbits increased in municipalities, where rabbit favourability also increased. The preservation of rabbit-friendly habitats should be a priority for the conservation of this key species in the western Mediterranean.
The conceptual evolution and practice of community-based natural resource management in southern Africa: past, present and future
Authors: CHILD BRIAN , BARNES GRENVILLE
Published: August 2010

This paper reviews the concept and practice of community-based natural resource management (CBNRM) as it has evolved in southern Africa, with a particular focus on Zimbabwe, Botswana, Namibia and, to a lesser extent, Zambia. It recognizes that, like democracy, CBNRM is both an imperfect process and a conceptual goal. The governance of economic processes, property rights and local political organization lie at the heart of CBNRM. The first challenge is to replace fiscal centralization, fees and bureaucracy (and the subsidization of alternative land uses) that have historically undervalued wild resources, so that CBNRM's comparative economic advantage is reflected in landholder and community incentives. Second, devolving property rights to communities shifts resource governance, responsibility and benefit appropriately to the local level. This necessitates accountable, transparent and equitable micro-governance, which in turn is linked to effective meso-level support and monitoring and cross-scale linkages between central government and local communities. This paper outlines the evolution of current models of CBNRM in the region and suggests core strategies for the next generation of CBNRM.
Sacred forests of India: a strong tradition of community-based natural resource management
Authors: ORMSBY ALISON A. , BHAGWAT SHONIL A.
Published: August 2010

Sacred forests represent an important long-held tradition of conserving specific land areas that have cultural, and often religious, significance. India, with its diversity of cultures and traditions, has over 100 000 sacred forests. Many of these groves are forest fragments in agricultural landscapes. In most cases, community members are at least aware of these fragments, if not actively involved in their protection and management. This review focuses on the Western Ghats in southern India and Meghalaya state in north-eastern India, both international biodiversity hotspots. In addition to the cultural significance of sacred forests, a number of studies have suggested that they are important refuges for conservation of biological diversity, including medicinal plants, within highly anthropogenic landscapes. Whilst sacred groves have been successful conservation areas, current threats to these forests are numerous, ranging from pressures for use of timber and other forest products to clearing for agriculture or general changes in cultural traditions. A variety of arrangements exist for ownership and management of sacred forests, making it necessary to identify solutions on a case-by-case basis. Support for the continued practice of the tradition of sacred forest protection is needed in order to provide a culturally sensitive model for community-based natural resource management.
Institutional choice and local legitimacy in community-based forest management: lessons from Cameroon
Authors: BROWN H. CAROLYN PEACH , LASSOIE JAMES P.
Published: August 2010

Decentralization of forest management has become a common policy globally which has allowed communities to regain rights removed through colonization and central state management of forests. However, socioeconomic and environmental outcomes of such community-based forest management schemes have been mixed. Studies have shown the importance of institutions in influencing the success of these new governance arrangements. Based on an extensive literature review supplemented by qualitative research, using focus groups and semi-structured interviews, conducted in nine villages in the humid forest zone comprising three community forests, this research investigated the successes and challenges from decentralization of forest management in Cameroon. A key constraint on success was the inappropriate institutional structure at the local level with responsibility to manage community forests. Community forest management committees with no internally recognized legitimacy and dominated by local elites had replaced roles once played by traditional authorities. Qualitative research showed that in the humid forest zone of Cameroon, the system of accountability for forest resources, prior to the enactment of community forest legislation, included those with historical traditional cultural authority, in the form of clan or lineage heads, as well as the village chief, a legacy of colonial power. Village chiefs or other members of the village council are also selected on the basis of their good moral character. Community forest management committees that are a hybrid of customary authorities and other representatives of the population chosen following the criteria for local legitimacy may capture the best of historical social regulation and build on it so that the local committee may be seen as being accountable to the local population. Since such hybrid institutions are not without their risks, it is important that these institutions be accountable to a local democratic government to further increase their transparency and accountability. Models of community-based natural resource management that incorporate culturally appropriate requirements of legitimacy and accountability in crafting local institutions may have more success in accomplishing both socioeconomic and environmental goals.
The establishment of a new ecological guild of pollinating insects on sub-Antarctic South Georgia
Authors: Convey P. , Key R.S. , Key R.J.D.
Published: August 2010

We report the establishment of two representatives of a new ecological functional group on the sub-Antarctic island of South Georgia - pollinating insects - in the form of the hoverfly Eristalis croceimaculata Jacobs (Diptera, Syrphidae) and the blowfly Calliphora vicina Robineau-Desvoidy (Diptera, Calliphoridae). The floricolous adults of these two species provide a new ecological role, pollination, in the ecosystems of this island. The activity of their respectively saprophogous or necrophagous larvae will also augment that of the native insect and microarthropod soil fauna. We discuss the potential new synergy between this functional group and that of a number of established non-native plants, reliant on insect pollinators for successful seed-set and hence dispersal, that are currently of persistent status with very limited local distributions.
Dietary profile of urban adult population in South India in the context of chronic disease epidemiology (CURES – 68)
Authors: Radhika Ganesan , Sathya Rangaswamy M , Ganesan Anbazhagan , Saroja Raghavan , Vijayalakshmi Parthasarathy , Sudha Vasudevan , Mohan Viswanathan
Published: August 2010

Objective

Few dietary surveys have been done with reference to chronic diseases, such as diabetes, in India, which is considered to be the diabetes capital of the world. We report on the dietary intake of urban adults living in Chennai, South India.

Design

A population-based cross-sectional study.

Setting

A representative population of urban Chennai in southern India.

Subjects

The study population comprised 2042 individuals aged ≥20 years selected from the Chennai Urban Rural Epidemiological Study (CURES). Dietary intake was measured using a validated and previously published interviewer-administered semi-quantitative meal-based FFQ.

Results

The mean daily energy intake was 10 393 (sd 2347) kJ (male: 10953 (sd 2364) kJ v. female: 9832 (sd 233) kJ). Carbohydrates were the major source of energy (64 %), followed by fat (24 %) and protein (12 %). Refined cereals contributed to the bulk of the energy (45·8 %), followed by visible fats and oils (12·4 %) and pulses and legumes (7·8 %). However, energy supply from sugar and sweetened beverages was within the recommended levels. Intake of micronutrient-rich foods, such as fruit and vegetable consumption (265 g/d), and fish and seafoods (20 g/d), was far below the FAO/WHO recommendation. Dairy and meat products intake was within the national recommended intake.

Conclusions

The diet of this urban South Indian population consists mainly of refined cereals with low intake of fish, fruit and vegetables, and all of these could possibly contribute to the risk of non-communicable diseases such as diabetes in this population.
Socio-economic and demographic variations in school lunch participation of French children aged 3–17 years
Authors: Dubuisson Carine , Lioret Sandrine , Dufour Ariane , Calamassi-Tran Gloria , Volatier Jean-Luc , Lafay Lionel , Turck Dominique
Published: August 2010

Objective

To assess school canteen attendance in a French nationally representative sample of children and to analyse its association with the socio-economic and demographic characteristics of the children and their families.

Design

Data from the second French national cross-sectional food consumption survey (INCA2), performed in 2006–2007, were used. Information on usual weekly school canteen attendance was collected through a self-reported questionnaire, and demographic and socio-economic variables through a face-to-face questionnaire. The associations between school canteen attendance and the socio-economic and demographic variables were investigated by multivariate logistic regression analyses.

Setting

The INCA2 sample was representative of the children aged 3–17 years in France.

Subject

Analysis was performed on 1413 schoolchildren who completed the school canteen attendance questions.

Results

Some 65·6 % of schoolchildren aged 3–17 years had school lunch at least once weekly. This rate of attendance was positively correlated with age. Whatever the school level, school canteen attendance was positively associated with the educational level of the caregiver/parent. In pre- and elementary-school children, enrolment at the school canteen was also higher when the caregiver/parent worked, or in single-parent families. In secondary-school children, school lunch participation decreased with children living in more densely populated areas and increased with the level of the household’s living standards.

Conclusions

School canteen attendance was positively associated with children’s socio-economic background. This could reduce the effectiveness of the forthcoming school meal composition regulations designed to improve the diet of children from deprived backgrounds, who are more likely to have unhealthy food habits.
Health technology appraisal and the courts: accountability for reasonableness and the judicial model of procedural justice
Authors: Syrett Keith
Published: August 2010

Recommendations issued by agencies undertaking appraisals of health technologies at the national level may impact upon the availability of certain treatments and services in some publicly funded health systems, and, as such, have regularly been subject to challenge, including by way of litigation. In addition to expertise in the evaluation of evidence, fairness of procedures has been identified as a necessary component of a claim to legitimacy in such circumstances. This article analyses the assessment of courts in three jurisdictions of the fairness of decision-making by such agencies and evaluates the judicial reading of procedural justice developed in this particular context against the conditions of ‘accountability for reasonableness’.
Archaea in artificial environments: Their presence in global spacecraft clean rooms and impact on planetary protection
Authors: Moissl-Eichinger Christine
Published: August 2010

The presence and role of Archaea in artificial, human-controlled environments is still unclear. The search for Archaea has been focused on natural biotopes where they have been found in overwhelming numbers, and with amazing properties. However, they are considered as one of the major group of microorganisms that might be able to survive a space flight, or even to thrive on other planets. Although still concentrating on aerobic, bacterial spores as a proxy for spacecraft cleanliness, space agencies are beginning to consider Archaea as a possible contamination source that could affect future searches for life on other planets. This study reports on the discovery of archaeal 16S rRNA gene signatures not only in US American spacecraft assembly clean rooms but also in facilities in Europe and South America. Molecular methods revealed the presence of Crenarchaeota in all clean rooms sampled, while signatures derived from methanogens and a halophile appeared only sporadically. Although no Archaeon was successfully enriched in our multiassay cultivation approach thus far, samples from a European clean room revealed positive archaeal fluorescence in situ hybridization (FISH) signals of rod-shaped microorganisms, representing the first visualization of Archaea in clean room environments. The molecular and visual detection of Archaea was supported by the first quantitative PCR studies of clean rooms, estimating the overall quantity of Archaea therein. The significant presence of Archaea in these extreme environments in distinct geographical locations suggests a larger role for these microorganisms not only in natural biotopes, but also in human controlled and rigorously cleaned environments.
Determinants of the distribution of nitrogen-cycling microbial communities at the landscape scale
Authors: Bru D , Ramette A , Saby N P A , Dequiedt S , Ranjard L , Jolivet C , Arrouays D , Philippot L
Published: August 2010

Little information is available regarding the landscape-scale distribution of microbial communities and its environmental determinants. However, a landscape perspective is needed to understand the relative importance of local and regional factors and land management for the microbial communities and the ecosystem services they provide. In the most comprehensive analysis of spatial patterns of microbial communities to date, we investigated the distribution of functional microbial communities involved in N-cycling and of the total bacterial and crenarchaeal communities over 107 sites in Burgundy, a 31 500 km2 region of France, using a 16 × 16 km2 sampling grid. At each sampling site, the abundance of total bacteria, crenarchaea, nitrate reducers, denitrifiers- and ammonia oxidizers were estimated by quantitative PCR and 42 soil physico-chemical properties were measured. The relative contributions of land use, spatial distance, climatic conditions, time, and soil physico-chemical properties to the spatial distribution of the different communities were analyzed by canonical variation partitioning. Our results indicate that 43–85% of the spatial variation in community abundances could be explained by the measured environmental parameters, with soil chemical properties (mostly pH) being the main driver. We found spatial autocorrelation up to 739 km and used geostatistical modelling to generate predictive maps of the distribution of microbial communities at the landscape scale. The present study highlights the potential of a spatially explicit approach for microbial ecology to identify the overarching factors driving the spatial heterogeneity of microbial communities even at the landscape scale.
Cooperation and Hamilton's rule in a simple synthetic microbial system
Authors: Chuang John S , Rivoire Olivier , Leibler Stanislas
Published: August 2010

A fundamental problem in biology is understanding the evolutionary emergence and maintenance of altruistic behaviors. A well‐recognized conceptual insight is provided by a general mathematical relation, Hamilton's rule. This rule can in principle be invoked to explain natural examples of cooperation, but measuring the variables that it involves is a particularly challenging problem and controlling these variables experimentally an even more daunting task. Here, we overcome these difficulties by using a simple synthetic microbial system of producers and nonproducers of an extracellular growth‐enhancing molecule, which acts as a ‘common good.’ For this system, we are able to manipulate the intrinsic growth difference between producers and nonproducers, as well as the impact of the common good on the growth rate of its recipients. Our synthetic system is thus uniquely suited for studying the relation between the parameters entering Hamilton's rule and the quantities governing the systems’ behavior. The experimental results highlight a crucial effect of nonlinearities in the response to the common good, which in general tend to limit the predictive value of Hamilton's rule.
Insulin Resistance and Oxidative Stress Influence Colony‐Forming Unit‐Endothelial Cells Capacity in Obese Patients
Authors: Miller‐Kasprzak Ewa , Bogdański Pawet , Pupek‐Musialik Danuta , Jagodziński Pawet P.
Published: August 2010

The aim of this study was to investigate the relationship between a sub‐population of endothelial progenitor cells (EPC), namely colony‐forming unit‐endothelial cells (CFU‐EC), their colony‐forming capacity and variable clinical parameters, including insulin resistance and oxidative stress, in obese individuals. Thirty‐eight obese adults (aged 42.5 ± 12.7), with BMI 32.3 ± 4.0 and 13 normal‐weight controls (aged 48.2 ± 12.9; BMI 23.2 ± 2.3) were studied. CFU‐EC colony‐forming capacity was impaired in the group of obese individuals compared to the normal‐weight controls (P = 0.001). The inverse correlation between homeostasis model assessment‐insulin resistance (HOMAIR) index and CFU‐EC number (r = −0.558, P < 0.0001) as well as positive total antioxidant status of plasma (TAS)/CFU‐EC relation were noticed during the study. Additionally, correlations between the concentration of triglycerides (TG), high‐density lipoproteins (HDLs), and body composition parameters in the obese participants were established. Our results demonstrate that insulin resistance and oxidative stress have a significant impact on the CFU‐EC colony formation in obesity. Moreover, in multivariate regression analysis, in both studied groups, the HOMAIR index and HDL concentration were independent predictors of the number of CFU‐EC. Endothelium dysfunction, which can be present in obesity, may in part be caused by EPC function impairment in this condition.
Different Impacts of Neck Circumference and Visceral Obesity on the Severity of Obstructive Sleep Apnea Syndrome
Authors: Kawaguchi Yuji , Fukumoto Shinya , Inaba Masaaki , Koyama Hidenori , Shoji Tetsuo , Shoji Shigeichi , Nishizawa Yoshiki
Published: August 2010

Our aim was to investigate the significance of neck circumference (NC) on the presence and severity of obstructive sleep apnea (OSA) syndrome independent of visceral fat (VF) obesity. A total of 219 subjects with suspected OSA underwent a complete polysomnography (PSG) study, along with the measurement of NC, and total body fat (TF) and VF levels (VFLs) measured by bioelectrical impedance analysis. We proposed NC divided by height (NC/H) as the simple index for height‐corrected NC in Japanese subjects. NC/H exhibited a significantly stronger correlation than NC per se with BMI (r = 0.781 vs. 0.675, P = 0.0178), TF (r = 0.531 vs. 0.156, P < 0.0001), and VF (r = 0.819 vs. 0.731, P = 0.0203), indicating that NC/H is a better indicator of visceral obesity than NC per se. Interestingly, despite the strong correlation between NC/H and VFL, VFL was significantly associated with the apnea‐hypopnea index (AHI) ≥5, ≥15, and ≥30, but not with ≥40 or ≥50, whereas NC/H was significantly associated with higher AHI values, i.e., AHI ≥50 but not with lower AHI value. Furthermore, multiple regression analyses revealed that VFL and NC/H were independently associated with the square root of AHI (AHI0.5) levels in obese and nonobese patients, respectively. In conclusion, NC is associated with the severity of OSA independently of visceral obesity, especially in nonobese patients.
Design, simulation, and measurement of metamaterial absorber
Authors: Cheng Yongzhi , Yang Helin
Published: August 2010

We present a design for metamaterial absorber which is resonant with strong absorbance in the microwave frequency range. Our fabricated design consists of two resonators and a metal wire that couple separately so as to absorb all incident electric and magnetic fields within a single planar layer which is only 0.9 mm thick. Experiments demonstrate that the transmission coefficients (S21) are lower than −10 dB across the entire measurement frequency range and the reflectance coefficients (S11) are about −20 dB around 10.4 GHz. The absorptivity which can be obtained through S parameters is greater than 98% around 10.4 GHz in experiments and 99.9% in simulations.
Minimal unitary representation of SU(2,2) and its deformations as massless conformal fields and their supersymmetric extensions
Authors: Fernando Sudarshan , Günaydin Murat
Published: August 2010

We study the minimal unitary representation (minrep) of SO(4,2) over a Hilbert space of functions of three variables, obtained by quantizing its quasiconformal action on a five dimensional space. The minrep of SO(4,2), which coincides with the minrep of SU(2,2) similarly constructed, corresponds to a massless conformal scalar in four space-time dimensions. There exists a one-parameter family of deformations of the minrep of SU(2,2). For positive (negative) integer values of the deformation parameter ζ, one obtains positive energy unitary irreducible representations corresponding to massless conformal fields transforming in (0,ζ∕2)((−ζ∕2,0)) representation of the SL(2,C) subgroup. We construct the supersymmetric extensions of the minrep of SU(2,2) and its deformations to those of SU(2,2|N). The minimal unitary supermultiplet of SU(2,2|4), in the undeformed case, simply corresponds to the massless N=4 Yang–Mills supermultiplet in four dimensions. For each given nonzero integer value of ζ, one obtains a unique supermultiplet of massless conformal fields of higher spin. For SU(2,2|4), these supermultiplets are simply the doubleton supermultiplets studied in the work of Gunaydin et al. [Nucl. Phys. B 534, 96 (1998); e-print arXiv:hep-th/9806042].
Spin transport in a tubular two-dimensional electron gas with Rashba spin-orbit coupling
Authors: Chen Chien-Liang , Chen Son-Hsien , Liu Ming-Hao , Chang Ching-Ray
Published: August 2010

We investigate the properties of local spin current and local spin density in a tubular two-dimensional electron gas system with Rashba spin-orbit coupling. To evaluate the spatial distribution of the spin-related quantities in both equilibrium and nonequilibrium cases, we derive the tubular version of tight-binding model and then employ the Landauer–Keldysh formalism. Our work reveals that the tubular geometry effect can cause spin-orbit-induced phenomena very different from those in a planar sample. In particular, a persistent spin current circulating in the tubular system is found to be robust against the disorder, thus suggesting its observability. In spite of the absence of spin accumulation, the spin Hall current can still arise and even circulate in the tubular sample. Moreover, a spin-independent impurity will induce distinctive spin accumulation patterns around the impurity, which may serve as a novel mechanism to control electron spins by arranging the impurities for spintronic devices.
Local measurements of tearing mode flows and the magnetohydrodynamic dynamo in the Madison Symmetric Torus reversed-field pinch
Authors: Ennis D. A. , Craig D. , Gangadhara S. , Anderson J. K. , Den Hartog D. J. , Ebrahimi F. , Fiksel G. , Prager S. C.
Published: August 2010

The first localized measurements of tearing mode flows in the core of a hot plasma are presented using nonperturbing measurements of the impurity ion flow. Emission from charge exchange recombination is collected by a novel high optical throughput duo spectrometer providing localized (±1 cm) measurements of C+6 impurity ion velocities resolved to <500 m/s with high bandwidth (100 kHz). Poloidal tearing mode flows in the Madison Symmetric Torus reversed-field pinch are observed to be localized to the mode resonant surface with a radial extent much broader than predicted by linear magnetohydrodynamic (MHD) theory but comparable to the magnetic island width. The relative poloidal flow amplitudes among the dominant core modes do not reflect the proportions of the magnetic amplitudes. The largest correlated flows are associated with modes having smaller magnetic amplitudes resonant near the midradius. The MHD dynamo due to these flows on the magnetic axis is measured to be adequate to balance the mean Ohm’s law during reduced tearing activity and is significant but does not exclude other dynamo mechanisms from contributing during a surge in reconnection activity.
Imaging of chromium point defects in p-type silicon
Authors: Habenicht Holger , Schubert Martin C. , Warta Wilhelm
Published: August 2010

In this work a method for the spatially resolved detection of the Cr point defect distribution in p-type silicon based on photoluminescence imaging was developed and successfully applied on monocrystalline and multicrystalline wafers. Chromium was identified by its metastable defect configuration and the association time during the formation of chromium–boron pairs. Further defects which could influence the Cr concentration determination have been studied and their influence was suppressed. For a quantitative evaluation of the chromium concentration, the knowledge of exact values of defect parameters such as energy level and capture cross sections for electrons and holes for both Cr states is essential. From the doping dependence of the lifetime, published defect parameters have been analyzed and adjusted slightly in order to explain experimental results. With these parameters reasonable averaged Cr point defect concentrations have been determined for different monocrystalline and multicrystalline samples. Furthermore, space-resolved images of the Cr point defect concentration could be acquired, permitting study of the distribution within a multicrystalline sample with respect to grains and grain boundaries or dislocation clusters.
Toward microscale Cu(In,Ga)Se2 solar cells for efficient conversion and optimized material usage: Theoretical evaluation
Authors: Paire Myriam , Lombez Laurent , Guillemoles Jean-François , Lincot Daniel
Published: August 2010

We develop a model to predict the performances of microscale Cu(In,Ga)Se2 (CIGS) solar cells under concentrated sunlight, based on the study of the influence of the window spread sheet resistance, which is the first limiting factor for concentration on CIGS solar cells. This model can be used to extract the value of the sheet resistance from simple current-voltage or electroluminescence measurements. The scaling benefits associated with the operation of microscale CIGS solar cells are studied. The optimum concentration ratio, linked to the best efficiency, is calculated for different cell sizes. It is predicted that an increase from 20% efficiency, for current CIGS solar cells under 1 sun illumination, up to 30% efficiency can be expected for microscale cells under concentrated sunlight.
InAs quantum wire induced composition modulation in an In0.53Ga0.37Al0.10As barrier layer grown on an InP substrate
Authors: Cui K. , Robinson B. J. , Thompson D. A. , Botton G. A.
Published: August 2010

Composition modulations are observed by transmission electron microscopy in In0.53Ga0.37Al0.10As barrier layers that overgrow both single- and multilayer InAs quantum wire structures grown on an InP substrate. Indium-rich (gallium-deficient) regions were observed in the region of the barrier layer lying directly above individual quantum wires, while indium-deficient (gallium-rich) regions were detected in the barrier above the gaps between adjacent underlying quantum wires. The magnitude of such modulation was typically 7% (atomic percent) for both indium and gallium as estimated from the energy dispersive x-ray analysis. The origin of such composition modulations was determined by modeling the chemical potential distribution for indium and gallium on the growth front of the barrier layer at the initial capping stage of the quantum wires with finite element simulations. It is found that the number and positions of the indium-rich regions are determined by the combined effects of strain and surface energy distributions on the barrier material capping the quantum wires. Moreover the estimated magnitudes of the composition modulation for both indium and gallium from the finite element models are in good agreement with the experimental observations. This method provides a simple way to understand the origin of, and to estimate the magnitude of the quantum wire-induced composition modulation in the barrier layer.
Evolution kinetics of nonequilibrium longitudinal-optical phonons generated by drifting electrons in III-nitrides: longitudinal-optical-phonon resonance
Authors: Rodrigues Clóves G. , Vasconcellos Áurea R. , Luzzi Roberto
Published: August 2010

The case of n-doped direct gap polar semiconductors in the presence of moderate to high electric fields is considered. The study is centered on the theoretical analysis of the behavior of LO phonons generated by drifting electrons. The emergence of a kind of “resonance” (or “overheating”) in the LO-phonon distribution which is centered on an off-center region of the Brillouin zone is evidenced. It consists in a preferential concentration of nonthermal populations of LO phonons in the form of a lobular distribution with its axis along the direction of the electric field. Numerical calculations performed for the case of strongly polar GaN accompanied with descriptive figures are presented.
Influence of pressure on the Pt nanoparticle growth modes during pulsed laser ablation
Authors: Riabinina Daria , Irissou Eric , Le Drogoff Boris , Chaker Mohamed , Guay Daniel
Published: August 2010

Pulsed laser deposition of a platinum target was performed in solution and in a He background gas atmosphere at pressures ranging from 10−5 to 11 Torr. The influence of the plasma dynamics on the structural properties of the nanostructured Pt films was investigated by time-of-flight and space-resolved emission spectroscopy (velocity measurements). It is shown that two different growth modes exist. In the first, formation of nanoparticle is occurring in the surrounding media (gas or solution), while in the second one, diffusion and reorganization of atomic species at the substrate surface is favored. In a gaseous environment, the transition between both modes is occurring at He pressure of ∼0.5 Torr, which corresponds to a velocity of ∼5.8×103 m s−1.
Statistical modeling of speech Poincaré sections in combination of frequency analysis to improve speech recognition performance
Authors: Jafari Ayyoob , Almasganj Farshad , Bidhendi Maryam Nabi
Published: August 2010

This paper introduces a combinational feature extraction approach to improve speech recognition systems. The main idea is to simultaneously benefit from some features obtained from Poincaré section applied to speech reconstructed phase space (RPS) and typical Mel frequency cepstral coefficients (MFCCs) which have a proved role in speech recognition field. With an appropriate dimension, the reconstructed phase space of speech signal is assured to be topologically equivalent to the dynamics of the speech production system, and could therefore include information that may be absent in linear analysis approaches. Moreover, complicated systems such as speech production system can present cyclic and oscillatory patterns and Poincaré sections could be used as an effective tool in analysis of such trajectories. In this research, a statistical modeling approach based on Gaussian mixture models (GMMs) is applied to Poincaré sections of speech RPS. A final pruned feature set is obtained by applying an efficient feature selection approach to the combination of the parameters of the GMM model and MFCC-based features. A hidden Markov model-based speech recognition system and TIMIT speech database are used to evaluate the performance of the proposed feature set by conducting isolated and continuous speech recognition experiments. By the proposed feature set, 5.7% absolute isolated phoneme recognition improvement is obtained against only MFCC-based features.
Conditions for the formation of nongyrotropic current sheets in slowly evolving plasmas
Authors: Schindler Karl , Hesse Michael
Published: August 2010

This paper addresses the formation of nongyrotropic current sheets resulting from slow external driving. The medium is a collisionless plasma with one spatial dimension and a three-dimensional velocity space. The study is based on particle simulation and an analytical approach. Earlier results that apply to compression of an initial Harris sheet are generalized in several ways. In a first step a general sufficient criterion for the presence of extra ion and electron currents due to nongyrotropic plasma conditions is derived. Then cases with antisymmetric magnetic and electric fields are considered. After establishing consistency of the criterion with the earlier case, the usefulness of this concept is illustrated in detail by two further particle simulations. The results indicate that the formation of nongyrotropic current sheets is a ubiquitous phenomenon for plasmas with antisymmetric fields that have evolved slowly from initial gyrotropic states. A fourth case concerns a plasma with a unidirectional magnetic field. Consistent with the general criterion, the observed final state is fluidlike in that it is approximately gyrotropic. Momentum balance is shown to include a contribution that results from accumulation of an off-diagonal pressure tensor component during the evolution. Heat flux also plays an important role.
Langevin and diffusion equation of turbulent fluid flow
Authors: Brouwers J. J. H.
Published: August 2010

A derivation of the Langevin and diffusion equations describing the statistics of fluid particle displacement and passive admixture in turbulent flow is presented. Use is made of perturbation expansions. The small parameter is the inverse of the Kolmogorov constant C0, which arises from Lagrangian similarity theory. The value of C0 in high Reynolds number turbulence is 5–6. To achieve sufficient accuracy, formulations are not limited to terms of leading order in C0−1 including terms next to leading order in C0−1 as well. Results of turbulence theory and statistical mechanics are invoked to arrive at the descriptions of the Langevin and diffusion equations, which are unique up to truncated terms of O(C0−2) in displacement statistics. Errors due to truncation are indicated to amount to a few percent. The coefficients of the presented Langevin and diffusion equations are specified by fixed-point averages of the Eulerian velocity field. The equations apply to general turbulent flow in which fixed-point Eulerian velocity statistics are non-Gaussian to a degree of O(C0−1). The equations provide the means to calculate and analyze turbulent dispersion of passive or almost passive admixture such as fumes, smoke, and aerosols in areas ranging from atmospheric fluid motion to flows in engineering devices.