bluuebunny/crossref_metadata_2025 huggingface dataset:
Rurality and Other Determinants of Early Colorectal Cancer Diagnosis in Nebraska: A 6‐Year Cancer Registry Study, 1998‐2003
Authors: Sankaranarayanan Jayashri , Watanabe‐Galloway Shinobu , Sun Junfeng , Qiu Fang , Boilesen Eugene , Thorson Alan G.
Published: September 2009

ABSTRACT: 
Background:

There are no studies of rurality, and other determinants of colorectal cancer (CRC) stage at diagnosis with population‐based data from the Midwest. Methods: This retrospective study identified, incident CRC patients, aged 19 years and older, from 1998‐2003 Nebraska Cancer Registry (NCR) data. Using federal Office of Management and Budget classifications, we grouped patients by residence in metropolitan, micropolitan nonmetropolitan, or rural nonmetropolitan counties (non‐core based statistical areas). In univariate and multivariate logistic regression analyses, we examined the association of the county classification and of other determinants with early (in situ/local) versus late (regional/distant) stage at CRC diagnosis. Results: Of the 6,561 CRC patients identified, 45% were from metropolitan counties, 24% from micropolitan nonmetropolitan counties and 31% from rural nonmetropolitan counties, with 32%, 38%, and 33%, respectively, being diagnosed at an early stage. Multivariate analysis showed micropolitan nonmetropolitan residents were significantly more likely than rural nonmetropolitan residents to be diagnosed at an early stage (adjusted OR, 1.22; 95% CI: 1.05‐1.42, P < .05). However, rural nonmetropolitan and metropolitan residents did not significantly differ in the likelihood of early diagnosis. Residents with Medicare rather than those with private insurance (P < .0001), married rather than unmarried residents (P < .01), and residents with rectal cancer rather than those with colon cancer (P < .0001) were more likely to be diagnosed at an early stage. Conclusions: Early CRC diagnosis needs to be increased in rural (non‐core) non‐metropolitan residents, unmarried residents, and those with private insurance.
Does Distance Matter? Distance to Mammography Facilities and Stage at Diagnosis of Breast Cancer in Kentucky
Authors: Huang Bin , Dignan Mark , Han Daikwon , Johnson Owen
Published: September 2009

ABSTRACT: 
Background:

National and regional data indicate that breast cancer early detection is low in Kentucky, especially rural regions, perhaps because access to mammography services can be problematic. Objective: This study examined the distance between residences of women diagnosed with breast cancer and the nearest mammography facility, as a risk factor for advanced stage diagnosis in rural populations. Methods: 1999‐2003 Kentucky Cancer Registry data were used for this study. A total of 12,322 women, aged 40 and older at diagnosis, with no previous history of cancer, and with known cancer stage were included. Travel distance was obtained using a geographic information system (GIS). Hierarchical logistic regression models were used to analyze the relationship between travel distance and advanced stage diagnosis. Results: Advanced diagnoses had longer average travel distances than early stage diagnoses (P < 0.01). After adjusting for age, race, insurance, and education at census tract level, the odds of advanced diagnosis were significantly greater for women residing over 15 miles from a facility, compared to those living within 5 miles (adjusted OR = 1.50, 95% CI = 1.25‐1.80). Conclusion: Although socioeconomic status, race, and age may help explain advanced diagnoses, longer travel distance also adversely affects early detection for rural populations. Accurate measurement of spatial accessibility indicators, such as travel distance, facilitates identification of at‐risk groups so that interventions can be developed to reduce this disease.
Cancer Risk Assessment by Rural and Appalachian Family Medicine Physicians
Authors: Kelly Kimberly M. , Love Margaret M. , Pearce Kevin A. , Porter Kyle , Barron Mary A. , Andrykowski Michael
Published: September 2009

ABSTRACT: 
Context:

Challenges to the identification of hereditary cancer in primary care may be more pronounced in rural Appalachia, a medically underserved region. Purpose: To examine primary care physicians’ identification of hereditary cancers. Methods: A cross‐sectional survey was mailed to family physicians in the midwestern and southeastern United States, stratified by rural/non‐rural and Appalachian/non‐Appalachian practice location (n = 176). Identification of hereditary breast‐ovarian cancer (BRCA1/2), hereditary non‐polyposis colon cancer (HNPCC), and other hereditary cancers was assessed. Findings: Less than half of physicians (45%) reported having patients with cancer genetic testing. Most (70%) correctly identified the BRCA1/2‐relevant scenario; 49% correctly identified the HNPCC‐relevant scenario. Factor analysis of psychosocial variables revealed 2 factors: Confidence (knowledge, comfort, confidence) and importance (responsible, important, effective, need) of identifying hereditary cancer. Greater confidence was associated with use of 3 generation pedigree in taking family history. Greater knowledge and access to genetic services were associated with use of genetic testing. More recent graduation year, greater knowledge, and greater confidence were associated with identifying the BRCA1/2‐relevant scenario. Greater knowledge and confidence were associated with identifying the HNPCC‐relevant scenario. Conclusions: Though rural Appalachian physicians do not differ in ability to identify high risk individuals, access barriers may exist for genetic testing. Interventions are needed to boost physician confidence in identifying hereditary cancer and to improve availability and awareness of availability of genetic services.
A comparative study of nursing staff, care recipients’ and their relatives’ perceptions of quality of older people care
Authors: Hasson Henna , Arnetz Judith E.
Published: September 2009

hasson h. & arnetz j.e. (2009) A comparative study of nursing staff, care recipients’ and their relatives’ perceptions of quality of older people care. International Journal of Older People Nursing 5, 5–15 doi: 10.1111/j.1748‐3743.2009.00186.x

Background.  Comparisons of different stakeholders’ ratings of the quality of older people care can help to drive quality improvement.

Aim.  The aim was to compare staff, older care recipients’ and their relatives’ quality of care ratings.

Design.  Cross‐sectional questionnaire surveys in 2003 and 2004, using a repeated measures design on an organizational level.

Methods.  Nursing staff, care recipients and relatives in two older people care organizations were included. The ratings of an overall quality grade, information, activities, general care and staff skills were compared between the respondent groups.

Results.  Care recipients in both organizations rated the overall quality grade significantly higher than nursing staff and relatives. Staff ratings of the information given to care recipients were significantly more positive than care recipients’ and relatives’ ratings. All three groups gave lowest ratings to the quality of activities offered to care recipients, with lowest ratings from nursing staff.

Conclusions.  Concurrent measurements of staff, care recipients and relatives’ care quality perceptions can provide a broad evaluation of an organization’s strength and limitations.

Relevance to clinical practice.  Staff, care recipients’ and relatives’ perceptions can be useful for older people care organizations and decision makers in developing care processes and outcomes of care.
Metrics: HRM's Holy Grail? A New Zealand case study
Authors: Tootell Beth , Blackler Meredith , Toulson Paul , Dewe Philip
Published: September 2009

What gets measured in business is noticed and acted on. The importance of human resource management (HRM) to be noticed as a vital key to business success has been argued profusely by the HRM profession over the last three decades. While the importance of human resource (HR) measurement is not disputed by business managers, the search for meaningful generic HR metrics is like HRM's Holy Grail. The purpose of this research is to investigate the issues confronting a sample of business organisations concerning measurement issues. It examines the current measurement practices used and their HR measurement needs. Developing appropriate HR measures, in terms of adding value, allows organisations to refocus their resources for leverage. Inappropriate measures simply encourage inappropriate behaviours not in the long‐term interests of the business. We know that HRM is less prepared than other business functions (like finance or management information systems) to quantify its impact on business performance. Our results suggest that HR metrics as the Holy Grail of HRM remain elusive. This research signals the importance of developing relevant and meaningful HR measurement models, while acknowledging that the actual metrics used (unlike accounting measures) may vary from business to business.
How can We Reduce the Distress Associated with Health Screening? From Psychological Theory to Clinical Practice
Authors: Bennett Paul
Published: September 2009

Health screening involves the early identification of risk factors for disease or early‐stage disease. There is clear evidence of a health benefit following many screening programs. However, these programs may also contribute to significant psychological distress in a significant minority of vulnerable individuals. This paper considers the impact of screening in relation to breast cancer, focusing on assessment of genetic risk for breast cancer and mammography. It then reviews how these programs presently try to minimize any distress among participants before examining how health and clinical psychological theory can contribute to the development of new interventions, focusing on the use of cognitive challenge and teaching appropriate emotion‐focused coping strategies such as mindfulness and distraction. Future research developments are then addressed.
Getting Emotional About Explanations: Social Explanations and Social Explanatory Styles as Bases of Prosocial Emotions and Intergroup Attitudes
Authors: Gill Michael J. , Andreychik Michael R.
Published: September 2009

We are interested in the bases of social emotions such as compassion and hostility. Our analysis centers on social explanations, or people’s answers to the question: Why does the target behave that way or experience those outcomes? Below, we review classic approaches to social explanation and then review work linking explanations to emotions. Finally, we focus on work from our lab that connects explanations to prosocial emotions and intergroup attitudes, including compassion for the disadvantaged and reduced vengefulness toward the violent. A crucial contribution of our work is to illuminate complex connections between explanations and emotions: A given explanation has different socio‐emotional implications depending on the explainer’s motives. Finally, we review our work suggesting that individuals have social explanatory styles, and that particular styles are predictive of dispositional compassion. A key implication of our work is that social explanations are another basis of prosociality, in addition to factors such as empathy and moral principles.
On the Relationship between Social Capital and Individualism–Collectivism
Authors: Realo Anu , Allik Jüri
Published: September 2009

Both social capital and individualism–collectivism (IC) have been, and still are, popular and well‐researched constructs in social sciences. Many theorists have argued that individualism poses a threat to social cohesion and communal association. Other researchers believe that growth of individuality, autonomy, and self‐sufficiency are necessary conditions for the development of social solidarity and cooperation. The present article reviews the studies on the relationship between social capital and IC, using different data and different measures. We conclude that countries with higher level of social capital (where people believe that most people can be trusted) are also more individualistic, emphasizing the importance of independence, personal accomplishments, and freedom to choose one’s own goals. In societies where trust is limited to the nuclear family or kinship alone, people have lower levels of social capital. Social capital increases as the radius of trust widens to encompass a larger number of people and social networks, bridging the ‘gap’ between the family and state.
The effect of deep sclerectomy on intraocular pressure of normal‐tension glaucoma patients: 1‐year results
Authors: Suominen Sakari , Harju Mika , Ihanamäki Tapio , Vesti Eija
Published: September 2009

Purpose:  To study the intraocular pressure (IOP)‐reducing effect of deep sclerectomy on normal‐tension glaucoma (NTG) patients.

Methods:  We retrospectively analysed 21 eyes of 18 consecutive NTG patients who had undergone deep sclerectomy with mitomycin‐C and a collagen implant.

Results:  Median (range) preoperative IOP was 15.1 mmHg (9.3–20.8) and median follow‐up time 13 months (12–18). At the 1‐year follow‐up visit, median IOP was significantly (P < 0.001) reduced to 10.5 mmHg (4–15) with median IOP reduction from preoperative values of 37% (12–78). Laser goniopuncture was performed in 10 eyes (48%) 1–16 months postoperatively. After 13 months’ follow‐up, a complete success at 20%, 25% and 30% IOP reduction levels was achieved in 67%, 62% and 52% of eyes, respectively. Few complications were encountered, but these included reduced visual acuity, problems with conjunctiva, microperforation, hyphaema, Dellen formation and encapsulated bleb. We encountered no complications related to postoperative hypotony.

Conclusion:  Deep sclerectomy with a collagen implant and mitomycin‐C was a safe and effective method for reducing IOP in NTG patients during 1‐year follow‐up.
Occupational exposure to polycyclic aromatic hydrocarbons and lung cancer risk: a multicenter study in Europe
Authors: Olsson Ann C , Fevotte Joelle , Fletcher Tony , Cassidy Adrian , 't Mannetje Andrea , Zaridze David , Szeszenia-Dabrowska Neonila , Rudnai Peter , Lissowska Jolanta , Fabianova Eleonora , Mates Dana , Bencko Vladimir , Foretova Lenka , Janout Vladimir , Brennan Paul , Boffetta Paolo
Published: September 2009

Background

Lung cancer incidence in Central and Eastern Europe (CEE) is among the highest in the world, and the role of occupational exposures has not been adequately studied in these countries.

Objectives

To investigate the contribution of occupational exposure to polycyclic aromatic hydrocarbons (PAH) to lung cancer in CEE.

Methods

A case–control study was conducted in the Czech Republic, Hungary, Poland, Romania, Russia and Slovakia, as well as the United Kingdom (UK) between 1998 and 2002. Occupational and socio-demographic information was collected through interviews from 2861 newly diagnosed lung cancer cases and 2936 population or hospital controls. Industrial hygiene experts in each country evaluated exposure to 70 occupational agents, whereof 15 mixtures containing PAH. ORs of lung cancer were calculated after adjusting for other occupational exposures and tobacco smoking.

Results

The OR for ever exposure to PAH in the CEE countries was 0.93 (95% CI 0.77 to 1.14). The ORs for the highest category of cumulative exposure, duration of exposure and intensity of exposure were 1.13 (95% CI 0.80 to 1.58), 1.02 (95% CI 0.66 to 1.57) and 1.11 (95% CI 0.60 to 2.05), respectively. The OR for ever PAH exposure in the UK was 1.97 (95% CI 1.16 to 3.35).

Conclusion

Occupational PAH exposure does not appear to substantially contribute to the burden of lung cancer in CEE. The apparently stronger effect observed in the UK may be due to high exposure levels and a joint effect with asbestos.
Respiratory health effects of ultrafine and fine particle exposure in cyclists
Authors: Strak Maciej , Boogaard Hanna , Meliefste Kees , Oldenwening Marieke , Zuurbier Moniek , Brunekreef Bert , Hoek Gerard
Published: September 2009

Objectives

Monitoring studies have shown that commuters are exposed to high air pollution concentrations, but there is limited evidence of associated health effects. We carried out a study to investigate the acute respiratory health effects of air pollution related to commuting by bicycle.

Methods

Twelve healthy adults cycled a low- and a high-traffic intensity route during morning rush hour in Utrecht, The Netherlands. Exposure to traffic-related air pollution was characterised by measurements of PM10, soot and particle number. Before, directly after and 6 h after cycling we measured lung function (FEV1, FVC, PEF), exhaled NO (FENO) and respiratory symptoms. The association between post- minus pre-exposure difference in health effects and exposure during cycling was evaluated with linear regression models.

Results

The average particle number concentration was 59% higher, while the average soot concentration was 39% higher on the high-traffic route than on the low-traffic route. There was no difference for PM10. Contrary to our hypothesis, associations between air pollution during cycling and lung function changes immediately after cycling were mostly positive. Six hours after cycling, associations between air pollution exposure and health were mostly negative for lung function changes and positive for changes in exhaled NO, although non-significant.

Conclusions

We found substantial differences in ultrafine particle number and soot exposure between two urban cycling routes. Exposure to ultrafine particles and soot during cycling was weakly associated with increased exhaled NO, indicative of airway inflammation, and decrements in lung function 6 h after exposure. A limitation of the study was the relatively small sample size.
A Robust Procedure for Estimating Salmon Escapement based on the Area-Under-the-Curve Method
Authors: English K. K. , Bocking R. C. , Irvine J. R.
Published: September 2009

Salmon spawning escapements are estimated using the area-under-the-curve (AUC) method by dividing the integral of the escapement curve by the average residence time of fish in the survey area. We present two forms of the basic AUC method which differ in the procedure used to estimate residence time from the observations of tagged fish during stream surveys. AUC estimates based on "observed residence times" were sensitive to variability in survey timing, observer efficiency, and tag detection, while those based on "total residence times" were more robust. For two coastal streams, escapement estimates based on "observed residence times" were between 1.1, and 6.8 times larger than an independent escapement estimate (from fence counts and mark–recapture data), while estimates based on "total residence times" were generally closer to the independent estimate (0.74–1.51 times the estimate, and within 26% six times out of seven). The consistency of our results under a wide variety of survey conditions, combined with their strong theoretical basis, indicates that an AUC method based on annual estimates of total residence time and observer efficiency is robust. However, the level of survey effort required for these methods would limit their application to high-priority streams or populations.
Size-Dependent Density of the Demersal Fish off Namibia: Patterns within and among Species
Authors: Gordoa Ana , Duarte Carlos M.
Published: September 2009

The density of the 40 most abundant demersal fish species off Namibia is inversely scaled to their average length, similar to the scaling of mortality to fish length. However, the density of individual fish species is, on average, scaled to the −2 power of average fish length in the aggregates, indicating that biomass increases (slope > −3) during the growth of most species examined. These findings indicate that size structure of these fish populations is primarily determined by mortality.
Food of the Alewife (Alosa pseudoharengus) in Lake Ontario before and after the Establishment of Bythotrephes cederstroemi
Authors: Mills Edward L. , O'Gorman Robert , DeGisi Joe , Heberger Roy F. , House Robert A.
Published: September 2009

Diets and length–weight relationships of Lake Ontario alewife (Alosa pseudoharengus) in 1972 differed from those in 1988; the large cladoceran Bythotrephes cederstroemi colonized the lake during the mid-1980's. Micro-crustacean zooplankton were the dominant prey of alewife during April–October in 1972 and 1988. Although Bythotrephes was not found in 1988 net samples, it replaced other zooplankters in the alewife's diet. Typically, tailspines were the only part of Bythotrephes in alewife stomachs; their frequency was high in April–May, diminished rapidly in summer and was very low by fall. In spring 1988, alewife [Formula: see text] were in better condition than in spring 1972 and this may have been due to larger fish feeding more heavily on Bythotrephes. Variation in diet among widely separated sampling sites was due to differences in alewife abundance, stability of thermal structure, progress of zooplankton community development and distance to the mouth of the Niagara River (through which Bythotrephes probably enter the lake in summer and fall). In the Great Lakes, inter- and intralake differences in diet clearly exist, and these must be incorporated into models of alewife planktivory to gain an accurate understanding of energy flow between trophic levels.
Juvenile Dungeness Crab (Cancer magister) Recruitment Variability and Oceanic Transport during the Pelagic Larval Phase
Authors: McConnaughey Robert A. , Armstrong David A. , Hickey Barbara M. , Gunderson Donald R.
Published: September 2009

The influence of environmental variability on Cancer magister year class strength was examined using trawl survey data from the Washington coast, 1983–88. Average June–September estimates of early instar abundance within two coastal estuaries and the adjacent nearshore are compared with alongshore and cross-shelf transport vectors during the preceding 4- to 5-mo pelagic larval phase. Settlement in the study area varied interannually by nearly 40-fold and was inversely related to net alongshore (northward) transport during January–May. Settlement was confined to a relatively narrow band along the coast and in estuaries; new recruits were rarely encountered beyond 46 m depth, corresponding to a distance of ~15 km from shore. We found no evidence for sustained westward Ekman transport to account for progressive seaward transport of zoeae, as proposed by other authors. Rather, persistent landward transport of near-surface waters will tend to minimize advective loss of larvae to seaward while promoting retention in proximity to suitable juvenile and adult habitat nearshore. Temporal and spatial continuity of northward transport during the winter months, coupled with proximity to high-risk areas downstream, suggests that Washington C. magister populations are frequently dependent on larvae originating to the south for recruitment.
Egg Weight, Fecundity, and Gonad Weight Variability among Northwest Atlantic Herring (Clupea harengus) Populations
Authors: Bradford Rodney G. , Stephenson Robert L.
Published: September 2009

Egg weight varies among northwest Atlantic herring (Clupea harengus) populations that spawn in different seasons (n = 12), but the range in weights is less than half of that known for northeast Atlantic populations. Egg weights were similar for both spring (May–June)- and autumn (August–October)-spawning herring (1.06 ×) and most dissimilar between spring- and summer (July)-spawning herring (1.21 ×). Mean population egg weights were not correlated with temperature either at spawning or for the last 2 mo of the egg development period. The product of egg weight and fecundity (standardized to length) differed between spring- and autumn-spawning herring of the southern Gulf of St. Lawrence. Spring-spawners, particularly smaller fish [Formula: see text], have lower ripe ovary weights than do autumn-spawning herring. Differences between spawning seasons in the relative allocation of storage energy to gonad and metabolism, a process mediated by the duration of the gonad maturation period, are the likely basis for the observed patterns.
Corynosoma wegeneri (Acanthocephala: Polymorphida) and Pseudoterranova decipiens (Nematoda: Ascaridoidea) Larvae in Scotian Shelf Groundfish
Authors: Marcogliese David J. , McClelland Gary
Published: September 2009

We examined larvae of the seal parasites Corynosoma wegeneri and Pseudoterranova decipiens in various fish species collected from Western and Sable Island banks between February 1989 and October 1990. Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), American plaice (Hippoglossoides platessoides), yellowtail flounder (Pleuronectes ferrugineus), windowpane (Scophthalmus aquosus), longhorn sculpin (Myoxocephalus octodecemspinosus), and sea raven (Hemitripterus americanus) were infected by both parasites, longhorn sculpin being a new host record for C. wegeneri. Only C. wegeneri occurred in winter flounder (Pleuronectes americanus), and neither parasite was found in northern sand lance (Ammodytes dubius) or capelin (Mallotus villosus). The two parasites were most numerous in sea raven and longhorn sculpin. Corynosoma wegeneri was more prevalent in fish sampled in 1989–90 than in previous surveys of Atlantic cod and haddock from the Scotian Shelf. Pseudoterranova decipiens and C. wegeneri occurred throughout the sampling area, but small fishes in the vicinity of Sable Island had the heaviest sealworm infections, and both parasites in longhorn sculpin declined with distance from Sable Island. Increases of C. wegeneri in groundfish, like recent increased levels of P. decipiens infection on the Scotian Shelf, can be attributed to the dramatic growth of the grey seal (Halichoerus grypus) population on Sable Island.
Orientation and Distribution of Individual Placopecten magellanicus (Gmelin) in Two Natural Populations with Differing Production
Authors: MacDonald B. A. , Bajdik C. D.
Published: September 2009

Spatial distribution patterns and orientation of individual scallops were determined for two natural populations of the sea scallop Placopecten magellanicus (Gmelin) from shallow coastal habitats in Newfoundland. The orientation of each scallop's dorsal–ventral axis and the positions of individuals relative to each other were determined from a composite image, constructed from a series of underwater photographs, of a grid (256 m2) laid on the bottom at each site. Estimates of the variance to mean ratio for the number of individuals per unit area indicated that scallops from Sunnyside were aggregated, while there was evidence of a haphazard pattern at Colinet. Most scallops from Sunnyside oriented themselves with the exhalant margin facing downstream or at least some portion of the inhalant margin directed into the prevailing current whereas scallops from Colinet were randomly oriented. Differences in density, individual orientation, and patterns of spatial distribution may be partially responsible for differences in growth rates and gonad production observed between the two populations.
AN INVERSE METHOD FOR PARAMETRIC TIMED AUTOMATA
Authors: ANDRÉ ÉTIENNE , CHATAIN THOMAS , FRIBOURG LAURENT , ENCRENAZ EMMANUELLE
Published: September 2009

We consider in this paper systems modeled by timed automata. The timing bounds involved in the action guards and location invariants of our timed automata are not constants, but parameters. Those parametric timed automata allow the modelling of various kinds of timed systems, e.g. communication protocols or asynchronous circuits. We will also assume that we are given an initial tuple π0 of values for the parameters, which corresponds to values for which the system is known to behave properly. Our goal is to compute a constraint K0 on the parameters, satisfied by π0, guaranteeing that, under any parameter valuation satisfying K0, the system behaves in the same manner: for any two parameter valuations satisfying K0, the behaviors of the timed automata are (time-abstract) equivalent, i.e., the traces of execution viewed as alternating sequences of actions and locations are identical. We present an algorithm InverseMethod that terminates in the case of acyclic models, and discuss how to extend it to the cyclic case. We also explain how to combine our method with classical synthesis methods which are based on the avoidance of a given set of bad states. A prototype implementation has been done, and various experiments are described.
HANDLING NON LEFT-LINEAR RULES WHEN COMPLETING TREE AUTOMATA
Authors: BOICHUT YOHAN , COURBIS ROMEO , HEAM PIERRE-CYRILLE , KOUCHNARENKO OLGA
Published: September 2009

This paper addresses the following general problem of tree regular model-checking: decide whether [Formula: see text] where [Formula: see text] is the reflexive and transitive closure of a successor relation induced by a term rewriting system [Formula: see text], and [Formula: see text] and [Formula: see text] are both regular tree languages. We develop an automatic approximation-based technique to handle this – undecidable in general – problem in the case when term rewriting system rules are non left-linear.
MULTIPROCESSOR INTERCONNECTION NETWORKS WITH SMALL TIGHTNESS
Authors: CVETKOVIĆ DRAGOŠ , DAVIDOVIĆ TATJANA
Published: September 2009

Homogeneous multiprocessor systems are usually modelled by undirected graphs. Vertices of these graphs represent the processors, while edges denote the connection links between adjacent processors. Let G be a graph with diameter D, maximum vertex degree Δ, the largest eigenvalue λ1 and m distinct eigenvalues. The products mΔ and (D+1)λ1 are called the tightness of G of the first and second type, respectively. In recent literature it was suggested that graphs with a small tightness of the first type are good models for the multiprocessor interconnection networks. In a previous paper we studied these and some other types of tightness and some related graph invariants and demonstrated their usefulness in the analysis of multiprocessor interconnection networks. We proved that the number of connected graphs with a bounded tightness is finite. In this paper we determine explicitly graphs with tightness values not exceeding 9. There are 69 such graphs and they contain up to 10 vertices. In addition we identify graphs with minimal tightness values when the number of vertices is n = 2,…, 10.
CONCERNING THE EQUATION OF STATE FOR A PARTIALLY IONIZED SYSTEM
Authors: BAKER GEORGE A.
Published: September 2009

I will discuss the expansion of various thermodynamic quantities about the ideal gas in powers of the electric charge, and I will discuss some cellular models. The first type of cellular model is appropriate for hydrogen. The second type is for Z > 1. It has the independent electron approximation within the atoms. These models are cross compared and minimal regions of validity are determined. The actual region of validity is expected to be larger. In the cellular models, the phase boundaries for liquid-gas transitions are found. For the second type of cellular model, in the part of the low-temperature, low-density region where there is not much expectation of validity of these methods, a non-thermodynamic region is found. I have devised a construction, similar in spirit to the Maxwell construction, to bridge this region so as to leave a thermodynamically valid equation of state. The non-thermodynamic region does not occur in hydrogen and it seems to be due to the inadequacy of the aforementioned approximation in that region.
ON THE "GENERALIZED SLATER" APPROXIMATION
Authors: MESSUD J. , DINH P. M. , SURAUD E. , REINHARD P.-G.
Published: September 2009

We work within the Density Functional Theory (DFT), in the Local Density Approximation (LDA) with Self Interaction Correction (SIC). We show that, thanks to a formulation which employs two different sets of orbitals, the equations can be written in the form of eigenvalues equations, leading to single electron interpretation. However, the resulting hamiltonian is non-local. We propose to find it's best local approximation within using the Optimized Effective Potential (OEP) method. The resulting approximate theory is denominated "Generalized Slater". We show that this new scheme cures the pathologies of the standard SIC-Slater or SIC-KLI approximations.
MICROSCOPIC APPROACH IN THE DESCRIPTION OF SLOWING OF ELECTROMAGNETIC PULSES IN BEC OF ALKALIS
Authors: SLYUSARENKO YURII , SOTNIKOV ANDRII
Published: September 2009

We propose a microscopic approach for a description of interaction of the ideal gas of alkali atoms with a weak electromagnetic radiation. The description is constructed in the framework of the Green functions formalism that is based on a new formulation of the second quantization method in case of the bound states (atoms) presence. For a gas in the Bose-condensed (BEC) state we study the dependencies of the propagation velocity and damping rate on the microscopic characteristics of the system. For a condensed dilute gas of sodium atoms we find the conditions of the group velocity reducing for optical pulses tuned up close to the resonant transitions. We also show that the slowing phenomenon can strongly depend on the intensity of the external static magnetic field.
HIGH-FREQUENCY RESPONSE AND VOLTAGE NOISE IN MAGNETIC NANOCOMPOSITES
Authors: BUZNIKOV N. A. , IAKUBOV I. T. , RAKHMANOV A. L. , KUGEL K. I. , SBOYCHAKOV A. O.
Published: September 2009

We study the noise spectra and high-frequency permeability of inhomogeneous magnetic materials consisting of single-domain magnetic nanoparticles embedded into an insulating matrix. Possible mechanisms of 1/f voltage noise in phase-separated manganites is analyzed. The material is modelled by a system of small ferromagnetic metallic droplets (magnetic polarons or ferrons) in insulating antiferromagnetic or paramagnetic matrix. The electron transport is related to tunnelling of charge carriers between droplets. One of the sources of the 1/f noise in such a system stems from fluctuations of the number of droplets with extra electron. In the case of strong magnetic anisotropy, the 1/f noise can arise also due to the fluctuations of the magnetic moments of ferrons.

The high frequency magnetic permeability of nanocomposite film with magnetic particles in insulating non-magnetic matrix is studied in detail. The case of strong magnetic dipole interaction and strong magnetic anisotropy of ferromagnetic granules is considered. The composite is modelled by a cubic regular array of ferromagnetic particles. The high-frequency permeability tensor components are found as a functions of frequency, temperature, ferromagnetic phase content, and magnetic anisotropy. The results demonstrate that magnetic dipole interaction leads to a shift of the resonance frequencies towards higher values, and nanocomposite film could have rather high value of magnetic permeability in the microwave range.
CRITICAL TEMPERATURE OF HIGH-Tc SUPERCONDUCTORS AND BOUNDARY CONDITIONS IN GINZBURG-LANDAU THEORY
Authors: LYKOV A.
Published: September 2009

New boundary condition for the order parameter in the Ginzburg-Landau theory is applied to the case of CuO 2 planes which are the main structural elements responsible for superconductivity in high-Tc superconductors. It was found that the order parameter in these superconductors is significantly depressed in the CuO 2 planes. As a result, this boundary condition to the GL equations is found to limit the critical temperature of high-Tc superconductors. Thus, in order to increase Tc of cuprate superconductors, the number of CuO 2 planes that are within a short distance of each other in unit cell or insulating properties of the layers located in the vicinity to the CuO 2 planes should be increased.
NOVEL MAGNETIC PROPERTIES IN MULTI-WALLED CARBON NANOTUBE MATS: CONSISTENT WITH THE PARAMAGNETIC MEISSNER EFFECT DUE TO ULTRAHIGH-TEMPERATURE SUPERCONDUCTIVITY
Authors: ZHAO GUO-MENG , BEELI PIEDER
Published: September 2009

We report magnetic measurements up to 1200 K on iron-contaminated multi-walled carbon nanotube mats with a Quantum Design vibrating sample magnetometer. Extensive magnetic data consistently show a ferrromagnetic transition at about 1000 K and a ferromagnetic-like transition at about 1275 K. The ferromagnetic transition at about 1000 K is associated with an Fe impurity phase and its saturation magnetization is in quantitative agreement with the Fe concentration measured by an inductively coupled plasma mass spectrometer. On the other hand, the saturation magnetization for the ferromagnetic-like phase (at 1275 K) is about four orders of magnitude larger than that expected from the measured concentration of Co or CoFe . We show that this ultrahigh-temperature ferromagnetic-like behavior cannot be explained by ferromagnetism of any Fe -carbon phases, carbon-based phases, or magnetic impurities, but is consistent with the paramagnetic Meissner effect (orbital ferromagnetism) due to the existence of π Josephson junctions in a granular superconductor.
NUMERICAL STUDY OF π-JUNCTION USING SPIN FILTERING BARRIERS
Authors: KAWABATA SHIRO , ASANO YASUHIRO
Published: September 2009

We numerically investigate the Josephson transport through ferromagnetic insulators (FIs) by taking into account its band structure. By use of the recursive Green's function method, we found the formation of the π junction in the case of the fully spin-polarized FI (FPFI), e.g., La 2 BaCuO 5. Moreover, the 0-π transition is induced by increasing the thickness of FPFI. On the other hand, Josephson current through the Eu chalcogenides shows the π junction behavior in the case of the strong d-f hybridization between the conduction d and the localized f electrons of Eu . Such FI-based Josephson junctions may becomes a element in the architecture of future quantum information devices.
TWO-DIMENSIONAL MACROSCOPIC QUANTUM DYNAMICS IN YBCO JOSEPHSON JUNCTIONS
Authors: KAWABATA SHIRO , KATO TAKEO , LOMBARDI FLORIANA , BAUCH THILO
Published: September 2009

We theoretically study classical thermal activation (TA) and macroscopic quantum tunneling (MQT) for a YBa2Cu3O7-δ( YBCO ) Josephson junction coupled with an LC circuit. The TA and MQT escape rate are calculated by taking into account the two-dimensional nature of the classical and quantum phase dynamics. We find that the MQT escape rate is largely suppressed by the coupling to the LC circuit. On the other hand, this coupling leads to the slight reduction of the TA escape rate. These results are relevant for the interpretation of a recent experiment on the MQT and TA phenomena in YBCO bi-epitaxial Josephson junctions.
JOSEPHSON PLASMA RESONANCE SPECTROSCOPY OF THE LAYERED SUPERCONDUCTORS WITH INTRINSIC JOSEPHSON EFFECT
Authors: GAIFULLIN MARAT B. , MATSUDA YUJI
Published: September 2009

Over 10 years pass after experimental discovery Josephson plasma resonance (JPR) in high-Tc superconductors. JPR spectroscopy became the powerful tool to study vortex phase diagram and interlayer electrodynamics in Josephson coupled layered superconductors like certain of high-Tc cuprates and molecular superconductors. We describe main principles of the JPR spectroscopy for measurement longitudinal plasma oscillations at the fundamental frequency ωp. That frequency and linewidth of resonance is directly related to the interlayer phase coherence. In this paper we report about developments and achievments in spectroscopy of JPR. The study of the vortex state of Bi 2 Sr 2 CaCu 2 O 8+δ and c-axis electrodynamics of Bi 2 Sr 2 CaCu 2 O 8+δ and Bi 2 Sr 2 CuO 6+δ w in zero magnetic field by JPR.
BOUNDS ON THE DOMINATION NUMBER OF PERMUTATION GRAPHS
Authors: GU WEIZHEN , WASH KIRSTI
Published: September 2009

For a graph G with n vertices and a permutation α on V(G), a permutation graph Pα(G) is obtained from two identical copies of G by adding an edge between v and α(V) for any v ϵ V(G). Let γ(G) be the domination number of a graph G. It has been shown that γ(G) ≤ γ(Pα(G) ≤ 2γ(G) for any permutation α on V(G). In this paper, we investigate specific graphs for which there exists a permutation α such that γ(Pα(G)) ≻ γ(G) in terms of the domination number of G or the maximum degree of G. Additionally, we construct a class of graphs for which the domination number of any permutation graph is twice the domination number of the original graph, as well as explore finding a specific graph G and permutation α for any two positive integers a and b with a ≤ b ≤ 2a, to have γ(G) = a and γ(Pα(G)) = b.
FAULT-TOLERANT MAXIMAL LOCAL-CONNECTIVITY ON CAYLEY GRAPHS GENERATED BY TRANSPOSITION TREES
Authors: SHIH LUN-MIN , CHIANG CHIEH-FENG , HSU LIH-HSING , TAN JIMMY J. M.
Published: September 2009

The local connectivity of two vertices is defined as the maximum number of internally vertex-disjoint paths between them. In this paper, we define two vertices as maximally local-connected, if the maximum number of internally vertex-disjoint paths between them equals the minimum degree of these two vertices. Moreover, we show that an (n-1)-regular Cayley graph generated by transposition tree is maximally local-connected, even if there are at most (n-3) faulty vertices in it, and prove that it is also (n-1)-fault-tolerant one-to-many maximally local-connected.
Wavelet Methods in Computational Fluid Dynamics
Authors: Schneider Kai , Vasilyev Oleg V.
Published: September 2009

This article reviews state-of-the-art adaptive, multiresolution wavelet methodologies for modeling and simulation of turbulent flows with various examples. Different numerical methods for solving the Navier-Stokes equations in adaptive wavelet bases are described. We summarize coherent vortex extraction methodologies, which utilize the efficient wavelet decomposition of turbulent flows into space-scale contributions, and present a hierarchy of wavelet-based turbulence models. Perspectives for modeling and computing industrially relevant flows are also given.
Species Distribution Models: Ecological Explanation and Prediction Across Space and Time
Authors: Elith Jane , Leathwick John R.
Published: September 2009

Species distribution models (SDMs) are numerical tools that combine observations of species occurrence or abundance with environmental estimates. They are used to gain ecological and evolutionary insights and to predict distributions across landscapes, sometimes requiring extrapolation in space and time. SDMs are now widely used across terrestrial, freshwater, and marine realms. Differences in methods between disciplines reflect both differences in species mobility and in “established use.” Model realism and robustness is influenced by selection of relevant predictors and modeling method, consideration of scale, how the interplay between environmental and geographic factors is handled, and the extent of extrapolation. Current linkages between SDM practice and ecological theory are often weak, hindering progress. Remaining challenges include: improvement of methods for modeling presence-only data and for model selection and evaluation; accounting for biotic interactions; and assessing model uncertainty.
First-Principles Study of Molecular Reactions at Metal/Perovskite-Oxide Interface
Authors: Shimojo Fuyuki
Published: September 2009

Molecular reactions at the metal/perovskite-oxide interface are investigated by ab initio molecular-dynamics simulations. The microscopic processes of dissociative adsorption of a hydrogen molecule on the metal surface are clarified. It is shown that excess oxygen atoms on the oxide surface promote the migration of the proton from the metal surface to the oxide. We also investigate the structural and dynamic properties of water molecules on the perovskite-oxide surface.
Performance and Microstructure of Porous LSCF-Ag Cermet Cathode for LSGM Electrolyte Solid Oxide Fuel Cells
Authors: Muranaka Minoru , Sasaki Kazuya , Suzuki Akihiro , Terai Takayuki
Published: September 2009

The relationships between the cathode performance and LSCF/Ag ratios and porosity of the LSCF-Ag cermet cathode were investigated. The Ag fractions in the LSCF-Ag powder were changed from 20 wt % to 80 wt %. The microstructures of the porous LSCF-Ag cermet cathodes were observed using a scanning electron microscope (SEM), and the area specific resistance (ASR) of the cathodes was measured by the two-probe AC impedance method. The LSCF-Ag cermet cathodes with different Ag fractions annealed at 750 ° for 3 h had the optimum microstructure and the lowest Rp when the Ag fraction in the LSCF-Ag cermet cathodes was 40 wt % or 50 wt %, and the LSCF-Ag cermet cathode including 50 wt % Ag had a sufficient porosity without the PMMA.
Multiple Length Scale Characterization of Doped Lanthanum Manganate Composite Cathodes
Authors: Gostovic Danijel , O'Hara Kathryn A. , Vito Nicholas J. , Wachsman E. D. , Jones Kevin S.
Published: September 2009

Composite cathodes extend the electrochemically active region for solid oxide fuel cells (SOFCs). The complex microstructural and chemical composition of composite cathodes often make them difficult to fully characterize. The active regions of composite cathodes were analyzed at various length scales using Focused Ion Beam/Scanning Electron Microscope (FIB/SEM) and Transmission Electron Microscope (TEM) techniques, to verify the effect of calcium doping on microstructure and interfacial stability. Dual beam FIB/SEM three-dimensional (3-D) reconstructions provided micron-level information on porosity, surface area and tortuosity while the TEM provided nanometer-level two-dimensional (2-D) chemical characterization of the interface between the cathode and electrolyte. These characterization techniques were applied on two different calcium doped lanthanum manganite (LCM)-scandium stabilized zirconia (SCZ) composite cathodes.
A Kinetic Study of Catalytic Activity Degradation of La0.6Sr0.4Co0.2Fe0.8O3-δ
Authors: Oh Dongjo , Yoo Jiho , Gostovic Danijel , Jones Kevin S. , Wachsman E. D.
Published: September 2009

The long term performance of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) was evaluated using electrical conductivity relaxation (ECR). The degradation rate of the chemical exchange coefficient (kchem) was faster than that of the chemical diffusion coefficient (Dchem) when LSCF was aged at 800 oC, which indicates surface degradation during the test. No crystallographic phase changes were detected by X-ray diffraction (XRD). Scanning electron microscopy (SEM), however, showed a significant change in surface morphology. SEM energy dispersive spectroscopy (EDS) and Auger electron spectroscopy (AES) showed that the surface was separated into two regions: A Sr rich phase on the grain boundaries and a Sr deficient top surface layer surrounding it. Transition metals were deficient in both phases. It is proposed that Sr is initially enriched to the top surface and diffuses to the grain boundary by surface diffusion. The preferential growth of Sr rich particles might be related to the Cr poisoning from the thermocouple sheath. From defect chemistry it is shown that both Sr rich particles and Sr deficient surface can contribute to the degradation of the catalytic activity of the cathode material by the reducing the oxygen vacancy and transition metal concentration.
Conductivity Variation of Yttria-Stabilized Zirconia Under Stress
Authors: Izumi Toru , Narumi Ryo , Sato Kazuhisa , Suzuki Ken , Yashiro Keiji , Hashida Toshiyuki , Mizusaki Junichiro
Published: September 2009

Electrical conductivity of 10 mol% yttria-stabilized zirconia (10YSZ) and YBa2Cu3O7-δ (YBCO) under stress were measured in the temperature range from 600oC to 800oC for 10YSZ and at 600oC for YBCO. It was observed that conductivity under stress slightly decreased for 10YSZ and increased for YBCO. In the case of 10YSZ, the conductivity change was caused by the change in mobility. In the case of YBCO, the conductivity change was caused by the change in mobility and change in carrier concentration.