bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of pre‐treatment of almond oil on ultraviolet B–induced cutaneous photoaging in mice
Authors: Sultana Yasmin , Kohli Kanchan , Athar M , Khar R K , Aqil M
Published: March 2007

Background  Ultraviolet (UV) radiation has been implicated in photoaging and various types of skin carcinomas. Although the human skin has evolved several defense mechanisms to survive the insults of actinic damage like keratinization, melanin pigmentation, etc., it is still subjected to the harmful effects of sunlight.

Aims  In this study, the role of almond oil in reducing the degradative changes induced in skin upon exposure to UV radiation was investigated.

Methods  Mice were divided in four groups of 20 animals. Group I was the control group. Group II was negative control, which received almond oil treatment alone. Group III was exposed to UV radiation only and Group IV received both UV treatment and almond oil treatment. Visible skin grading assessed the changes based on a rating scale, biochemical tests (glutathione estimation and lipid peroxidation), and histopathologic studies.

Results  Upon exposure of mice to UV radiation, it was found that pronounced visible skin changes were seen after 12 weeks of exposure. The results of the biochemical tests, glutathione estimation, and lipid peroxidation showed that almond oil reduced the effect of UV light–induced photoaging on the skin. Histopathologic studies also indicated a photoprotective effect of almond oil on the skin after UV exposure.

Conclusions  It was concluded that topical almond oil is capable of preventing the structural damage caused by UV irradiation and it was also found useful in decelerating the photoaging process.
Dutasteride improves male pattern hair loss in a randomized study in identical twins
Authors: Stough Dow
Published: March 2007

Objectives  This study compared the efficacy of dutasteride vs. placebo in the treatment of male pattern hair loss (androgenetic alopecia) in 17 pairs of identical twin males with androgenetic alopecia over a 1‐year period.

Methods  In this randomized, double‐blind, placebo‐controlled, single‐center study, one twin from each identical twin pair received dutasteride 0.5 mg/day for 12 months while the other received placebo for 12 months. Hair growth was evaluated using standardized clinical photographs, hair counts, and patient self‐assessment questionnaires.

Result  Dutasteride significantly improved hair growth at 1‐year compared to placebo based on the analysis of the investigator assessment and the patient self‐assessment questionnaires. Sixteen of 17 sets of twins completed the study, of which 15 sets correctly predicted the use of dutasteride. Only one set could not determine the active drug from the placebo.

Conclusion  Through the use of identical twins, this randomized trial provides evidence that dutasteride significantly reduces hair loss progression in men with male pattern hair loss.
Managing visitor access to seabird colonies: a spatial simulation and empirical observations
Authors: BEALE COLIN M.
Published: March 2007

Managers of wildlife reserves have a range of tools available to them when considering the best way to provide visitor access while avoiding as many of the negative effects of human disturbance as possible. However, managers lack guidelines as to whether conservation interests are best met by spreading visitors thinly throughout a reserve or by aggregating them in a small area. Here I describe how relationships between disturbance impact and disturbance pressure (the dose–response curve) can be used to address this issue. I generate a spatial simulation of two different models of visitor distribution (one more aggregated than the other) and explicitly model disturbance impact for a variety of dose–response curves. I show that the optimal visitor distribution is likely to depend on the sensitivity of the species and the overall visitor pressure. Importantly, I find that in certain circumstances optimal management can shift from one management option to the other if visitor numbers cross a certain threshold. I use published relationships predicting nesting success of Common Guillemots Uria aalge and Black‐legged Kittiwakes Rissa tridactyla to assess optimal management at three nature reserves in Scotland. Optimal management for Guillemots depends on the number of people and the distance between the people and the birds. At sites with high disturbance pressures, management should aim to aggregate visitors in as small an area as possible, whereas at sites with lower disturbance pressure, an even distribution of visitors is favoured. Kittiwake models were not generally accurate, and consequently only site‐specific guidelines could be generated, where an even distribution was favoured.
Approaches to measuring the effects of human disturbance on birds
Authors: GILL JENNIFER A.
Published: March 2007

Human recreational activities are often considered as potential threats to biodiversity, by restricting animals’ access to resources that otherwise would be exploited. Because access to wildlife areas is one major means of increasing their public value, and hence the pressure to conserve them, it is clearly critical to be able to identify accurately when human presence is a threat to conservation and when it is not. A wide range of methods have been used to assess the impacts of human disturbance on wildlife and these methods are summarized here. The type of method used depends principally on whether the disturbance issue relates to a particular site, a particular group of individuals or whole populations. Within these categories, both comparative and experimental approaches have been used to assess behavioural, distributional, demographic and population responses to human presence. Examples of each approach are given here, together with an assessment of the information each method provides.
How perception and density‐dependence affect breeding Woodlarks Lullula arborea
Authors: MALLORD J. W. , DOLMAN P. M. , BROWN A. F. , SUTHERLAND W. J.
Published: March 2007

There is often a perceived conflict between allowing recreational access to the countryside and wildlife conservation. Although many studies have investigated potential impacts on birds, few have assessed the potential impacts of recreational disturbance at the population scale. We studied the impact of disturbance on a Woodlark Lullula arborea population on 16 heathland sites in southern England (Mallord et al. 2006). These sites all had historical records of breeding Woodlarks, and together encompassed a range of visitor access levels. A logistic regression model of patch use was used to quantify habitat suitable for Woodlarks. Woodlarks favoured patches with substantial proportions of bare ground and short vegetation. Across sites, Woodlark density (per hectare of suitable habitat) was lower in sites with higher levels of disturbance. Within sites with recreational access, the probability of suitable habitat being colonized was lower in those areas with greater disturbance; this was reduced to below 50% at around eight disturbance events per hour. There was no effect of disturbance on daily nest survival rates. Birds on sites with higher levels of disturbance fledged more chicks (per pair) owing to a strong density‐dependent increase in reproductive output. A model is presented (Mallord et al. 2007) that predicts the consequences for the Woodlark population of a range of access scenarios. The model suggested that recreational disturbance is already having a major effect on the Woodlark population. Additionally, it predicted that any further impact on the population depended on both the numbers of people and their spatial distribution. Under current access arrangements, a doubling of visitor numbers had little effect, whereas the same number of people distributed evenly across all sites led to a major negative impact on the population. Many previous studies have stressed the negative effects of recreational disturbance on bird behaviour, distribution and breeding success. However, from a conservation viewpoint, the impact at the population level is of paramount importance. Modelling the consequences of alternative access scenarios will help policymakers in the development of appropriate mitigation measures.
Compulsory Generic Switching of Antiepileptic Drugs: High Switchback Rates to Branded Compounds Compared with Other Drug Classes
Authors: Andermann Frederick , Duh Mei Sheng , Gosselin Antoine , Paradis Pierre Emmanuel
Published: March 2007

Summary:  Purpose: Compulsory generic substitution of antiepileptic drugs (AEDs) may lead to adverse effects in epilepsy patients because of seizure recurrence or increased toxicity. The study objectives were (a) to quantify and compare the switchback rates from generic to brand‐name AEDs versus non‐AEDs, and (b) to assess clinical implications of switching from branded Lamictal to generic lamotrigine (LTG) and whether signals exist suggesting outcome worsening.

Methods: By using a public‐payer pharmacy‐claims database from Ontario, Canada, switchback rates from generic to branded AEDs [Lamictal, Frisium (clobazam; CLB), and Depakene (VPA; divalproex)] were calculated and compared with non‐AED long‐term therapies, antihyperlipidemics and antidepressants, in January 2002 through March 2006. We then assessed pharmacy utilization and AED dosage among LTG patients switching back to branded Lamictal compared with those staying on generic formulation.

Results: The 1,354 patients (403 monotherapy, 951 polytherapy) were prescribed generic LTG, of whom 12.9% switched back to Lamictal (11.7% monotherapy, 13.4% polytherapy). Switchback rates of other AEDs were ∼20% for CLB and VPA. The switchback rates for AEDs were substantially higher than for non‐AEDs (1.5–2.9%). Significant increases in LTG doses were observed after generic substitution for those who did not switch back (6.2%; p < 0.0001). The average number of codispensed AEDs and non‐AED drugs significantly increased (p < 0.0001) after LTG generic entry, especially in the generic group.

Conclusions: These results reflect poor acceptance of switching AEDs to generic compounds. They may also indicate increased toxicity and/or loss of seizure control associated with generic AED use.
Development, Worsening, and Improvement of Diabetic Microangiopathy in Older People: Six‐Year Prospective Study of Patients Under Intensive Diabetes Control
Authors: Katakura Masafumi , Naka Motoji , Kondo Teruki , Komatsu Mitsuhisa , Yamauchi Keishi , Hashizume Kiyoshi , Aizawa Toru
Published: March 2007

OBJECTIVES: To examine retinopathy and nephropathy in elderly patients with diabetes mellitus (DM) under intensive multifactorial DM control.

DESIGN: Six‐year interventional observation study.

SETTING: Multicenter study including four hospitals.

PARTICIPANTS: Four hundred thirteen elderly (≥65) patients with type 2 DM attending each hospital for 1 year or longer; those receiving hemodialysis or with uncured malignancy were excluded.

MEASUREMENTS: Development, worsening, and improvement of retinopathy and nephropathy and respective risk factors.

RESULTS: The mean baseline hemoglobin (HbA1c), blood pressure (BP), and total cholesterol were 6.8%, 137/74 mmHg, and 5.13 mmol/L, respectively. Retinopathy developed in 45 of 168 (27%) patients and, of 63 with nonproliferative retinopathy, worsened and improved in 11 (17%) and 23 (37%), respectively. Nephropathy developed in 53 of 227 (23%) patients and improved in 13 of 51 (25%) having it baseline. The mean change in glomerular filtration rate (ΔGFR, baseline GFR–GFR at the end of the study period) in those with nephropathy at baseline was 21.5 mL/min. HbA1c was related to development of retinopathy (P=.001, odds ratio (OR)=1.91), and serum creatinine (P=.03, OR=1.02), systolic BP (SBP) (P=.03, OR=1.22), and prior stroke (P=.005, OR=3.21) were related to development of nephropathy. In patients with nephropathy at baseline, SBP (P=.03, Spearman's rho (ρ)=0.310), total cholesterol (P=.01, ρ=0.361), and low‐density lipoprotein cholesterol (P=.03, ρ=0.322) were correlated with ΔGFR.

CONCLUSION: In elderly patients under intensive control for DM, the outcome of microangiopathy is favorable. Modifiable risk factors were hyperglycemia for development of retinopathy and hypertension and hypercholesterolemia for development or worsening of nephropathy; prior stroke was an unmodifiable risk factor for development of nephropathy.
Adolescent Fathers' Parenting Stress, Social Support, and Involvement with Infants
Authors: Fagan Jay , Bernd Elisa , Whiteman Valerie
Published: March 2007

The present study examined the relationship between concurrent measures of adolescent fathers' parenting stress, social support, and fathers' care‐giving involvement with the 3‐month‐old infant, controlling for fathers' prenatal involvement. The study sample consisted of 50 teenage father–mother dyads. Findings from multivariate regression revealed that fathers' parenting stress was significantly and negatively related to fathers' care giving as perceived by both fathers and mothers. The relationship between support for father involvement provided by the young man's parents and father reported care‐giving involvement approached significance. Social support from both teenagers' parents buffered the negative influence of parenting stress on fathers' involvement with the baby. Policy and intervention implications are discussed.
Grandmothers' Involvement Among Young Adolescents Growing Up in Poverty
Authors: Pittman Laura D.
Published: March 2007

Grandmothers often play an important role in low‐income minority families through providing support to their adult children as well as care to their grandchildren. However, little is known about how varying types of grandmother involvement may influence their grandchildren's functioning. This paper uses data from Welfare, Children, and Families: A Three‐City Study, a longitudinal study sampling low‐income minority youth from high‐poverty neighborhoods, to explore how young adolescents (age 10–14 years at Time 1) function over time based on grandmothers' residential status and their level of caretaking responsibility. Analyses find that young adolescents with a custodial grandmother displayed greater levels of externalizing problem behaviors over time while young adolescents with a co‐residing grandmother reported fewer depressive symptoms over time as compared with their peers. The importance of considering the influence of grandmothers who are more involved, especially among low‐income, minority families, in research and practice will be discussed.
Adolescents' and Their Mothers' Perceptions of Parental Management of Peer Relationships
Authors: Mounts Nina S.
Published: March 2007

The purpose of the present investigation was to examine the relation of level and discrepancy in mothers' and adolescents' reports of parental management of peer relationships and parent–child conflict about peer relationships to mothers' and adolescent's reports of adolescents' drug use, delinquent behavior, and grade‐point‐average (GPA). An ethnically diverse sample of 121 seventh and eighth graders and their mothers completed questionnaires assessing the degree to which mothers managed peer relationships, parent–child conflict about peer relationships, and adolescents' drug use, delinquent behavior, and GPA. Differences in mothers' versus adolescents' reports were found for parental management of peers and conflict about peer relationships. Results suggest that both level and discrepancies between mothers' and adolescents' reports of parenting are important in predicting the outcome variables. Furthermore, the direction of the discrepancy was important in determining its relation to the outcome variables.
Navigating the Transition to Multi‐Ethnic Urban High Schools: Changing Ethnic Congruence and Adolescents' School‐Related Affect
Authors: Benner Aprile D. , Graham Sandra
Published: March 2007

This short‐term longitudinal study investigated 918 students' school‐related affect across the transition to high school. The study focused specifically on the moderating effect of change in student ethnic congruence from middle to high school. Results indicate that students experiencing more ethnic incongruence from middle to high school, in particular African American and male students, reported declining feelings of school belonging over time. Moreover, students experiencing ethnic incongruence also had increasing worries about their academic success. These results suggest that the changing school demographics from middle school to high school may negatively impact students' school‐related affect, especially if they move to high schools which include fewer students who are ethnically similar to themselves.
Transcriptional regulation of theDrosophila rfc1gene by the DRE–DREF pathway
Authors: Tsuchiya Akihiro , Inoue Yoshihiro H. , Ida Hiroyuki , Kawase Yukari , Okudaira Koji , Ohno Katsuhito , Yoshida Hideki , Yamaguchi Masamitsu
Published: March 2007

The DNA replication‐related element (DRE) is a common 8‐bp sequence (5′‐TATCGATA) found in the promoters of many DNA replication‐related genes, to which DRE‐binding factor (DREF) specifically binds to activate transcription. Replication factor C (RFC) is an essential five‐subunit complex in DNA replication, the largest subunit being RFC140. We first identified the gene (rfc1) encoding theDrosophilaRFC140 (dRFC140) protein and then isolated a mutant. The phenotypes suggested that the gene is essential for cell‐cycle progression, and immunocytochemical studies also indicated a relation between its expression and the cell cycle. Therfc1gene contains three DRE‐like sequences in its 5′‐flanking region, one of them perfectly matching DRE and the other two demonstrating a match in seven of eight nucleotides. These sequences were named DRE1 (−63 to −69), DRE2 (−378 to −385), and DRE3 (−1127 to −1134), respectively. Immunostaining of polytene chromosomes in third‐instar larvae using anti‐DREF sera detected a specific band in 82E2 of 3R chromosome, containing therfc1gene region. Band‐mobility shift assays usingDrosophilaKc cell nuclear extracts revealed that DREF binds to DRE1, ‐2, and ‐3in vitro, and chromatin immunoprecipitation using anti‐DREF IgG confirmed that this occursin vivo. Luciferase transient expression assays in S2 cells further suggested that DREs in therfc1promoter are involved in transcriptional regulation of the gene. Moreover,rfc1promoter activity was reduced by 38% in DREF double‐stranded RNA‐treated S2 cells. These results indicate that DREF positively regulates therfc1promoter.
A NEW ALLIANCE IN NEW YORK STATE: A PROGRESS REPORT ON THE LABOR MOVEMENT'S RESTRUCTURING, CAPACITY BUILDING, AND PROGRAMMATIC WORK
Authors: Grabelsky Jeff
Published: March 2007

The labor movement in New York State (NYS) has undergone a dramatic restructuring that is part of a national American Federation of Labor–Congress of Industrial Organizations program called the New Alliance. The purpose of the New Alliance is to build the capacity of local labor movements and to empower unions to help shape a region's political and economic agenda. The restructuring in NYS led to the consolidation of twenty‐five central labor councils into five area labor federations, each of which is developing the resources, staff, and leadership to help grow labor's regional power across the state. This article describes the origins of the New Alliance, the nature of the restructuring process, the ways in which the capacity of local labor movements are expanding, the programmatic work the restructured central bodies have undertaken in the last five years, and the impact of the national split on local and regional central bodies across NYS.
ATLANTA: LOCAL INITIATIVE COMBINES WITH NATIONAL SUPPORT
Authors: Karson Tom
Published: March 2007

For over a decade the Atlanta‐North Georgia Labor Council has had a reputation as an activist council engaged in innovative coalition building. Looking to build on this work and learning from the power‐building experiences in California and elsewhere, the Council founded the nonprofit Georgia Stand‐Up in 2005. The new organization immediately leaped into coalition work around Atlanta's massive new economic development initiative—the BeltLine Project. This article looks at how local leadership was able to combine seeds laid by prior work with national support to produce a dynamic example of the new second generation of regional power building.
YAMAZAWA'S OPEN ECONOMIC ASSOCIATION: AN INDIAN OCEAN GROUPING FOR ECONOMIC COOPERATION
Authors: SHAND Ric , KALIRAJAN K. P.
Published: March 2007

With the landmark economic reforms in South Asia and political changes in South Africa, several issues concerning trade and investment have emerged within the Indian Ocean region and internationally. Following the concept of “open economic association” introduced by Yamazawa, the question examined in this paper is whether a market‐driven economic integration is emerging involving the Indian Ocean Rim countries.
STRUCTURAL CHANGES AND SPECIALIZATION IN BRAZILIAN INDUSTRY: THE EVOLUTION OF LEADING COMPANIES AND THE M&A PROCESS
Authors: ROCHA FREDERICO , KUPFER DAVID
Published: March 2007

This paper analyzes changes in the Brazilian productive structure and in ownership structures of leading companies during the 1990s. It uses information from balance sheets published in Gazeta Mercantil and from the Thomson Financial Securities Data database on M&A. The main findings are: (i) the sectoral distribution of leading companies has remained stable; (ii) there has been a strong change in the ownership structure in Brazil, with an increase in the participation of multinational enterprises (MNEs) in the sample of leading companies; (iii) this increase in participation may be partially, though not integrally, explained by M&A transactions; (iv) though the M&A process has been quite intensive in the period, productive concentration has decreased among the group of leading companies; and (v) acquiring firms have adopted specializing strategies during the period. This trend is even clearer when private national enterprises (PNEs) are examined separately.
WILL THE MARKET KEEP BRAZIL LIT UP? OWNERSHIP AND MARKET STRUCTURAL CHANGES IN THE ELECTRIC POWER SECTOR
Authors: HAMAGUCHI NOBUAKI
Published: March 2007

After achieving significant success until the 1970s, the Brazilian electric power sector stalled due to financial problems. The government promoted a shift toward a private ownership model and tried to entrust the market with creating a stable and efficient energy supply. However, the energy crisis highlighted the difficulties in this transition. This paper points out that the uncertainty inherent in the market‐based model increased information rent for the private companies and complicated the post‐privatization expansion scenario. Privatization driven by macroeconomic problems should be carefully reexamined, especially for public utilities with strong natural monopoly characteristics, since markets tend to fail to supply the socially optimal supply, thus directly affecting people's lives.
TECHNOLOGICAL CHANGE AND DEMAND FOR SKILLS IN DEVELOPING COUNTRIES: AN EMPIRICAL INVESTIGATION OF THE REPUBLIC OF KOREA'S CASE
Authors: KANG Seoghoon , HONG Dong‐Pyo
Published: March 2007

There are few studies that directly address the upskilling issues in developing countries. Since theoretical analyses of these issues usually yield different results, upskilling in developing counties, and the factors of upskilling, if any, are rather empirical questions. This study shows that upskilling that occurs in developed countries in terms of the ratio of the number of white‐collar workers to that of blue‐collar workers also occurred in the Republic of Korea, one of developing countries. Increasing demand for highly‐skilled workers reflected in their employment and wage shares can be largely explained by “within industry’ shifts, not by “between industry” shifts, especially in the manufacturing industry. To further investigate the causes of these shifts, changes in white‐collar shares are regressed on the capital‐output and R&D‐sales ratio. Estimated coefficients are all positive, suggesting capital‐skill complementarities and skill‐biased technological change.
STATE REFORMATION AND THE FORMATION OF A NEWLY EMERGING WELFARE STATE IN TAIWAN
Authors: Chen‐Wei Lin
Published: March 2007

In postwar Taiwan, the legitimacy of the Kuomintang (KMT) regime had depended on the cold war structure and the civil war with the Communist Party. As the KMT regime penetrated Taiwanese society, it exercised tight control over the society through the medium of the strong party organization. However, in the process of democratization that started in the 1980s, the KMT's authoritarian political rule began to crumble, forcing the government to respond to people's demands in order to survive. The reform and improvement of the social security system in Taiwan were brought about against this backdrop of state reformation.
SOCIAL SECURITY REFORM BY THE CARDOSO GOVERNMENT OF BRAZIL: CHALLENGES AND LIMITATIONS OF REFORM TEN YEARS AFTER “DEMOCRATIZATION”
Authors: Koyasu Akiko
Published: March 2007

This article has two purposes. The first is to analyze politically why the Cardoso government's social security reform could not be completed. Though democratic political systems (election and political party systems) were reintroduced after the re‐democratization in 1985, Brazil continued to suffer from elements of its traditional political culture such as corporatism, clientelism, nepotism, etc. These were the stumbling blocks for Cardoso's reform. The second purpose is to deepen understanding of Brazilian democracy by casting light on the behavior of political actors (the government, congress, and political parties) over social security reform issues under the Cardoso and Lula governments.
Bone health: the effect of androgen deprivation therapy in prostate cancer patients
Authors: Drudge‐Coates Lawrence
Published: March 2007

Androgen deprivation therapy (ADT) in the management of prostate cancer poses a considerable risk to bone health in prostate cancer patients, throughout their continuum of care. Associated decreases in bone mineral density and an increased risk of fracture can lead to major quality‐of‐life concerns and an adverse impact on morbidity and mortality, in an often already overburdened patient. Urology nurses in their administration and monitoring of the effects of ADT are essential for identifying at‐risk patients and ensure timely and effective assessment and treatment. As health educators, they are ideally situated to promote and influence patients to adopt essential lifestyle changes in a multidisciplinary arena, to reduce risk factors. Supportive treatments are available to significantly reduce both bone loss and fracture risk that can easily be adopted by urology nurses in their existing clinical working environments to further strengthen positive management strategies for bone health.
Water, Adaptation, and Property Rights on the Snake and Klamath Rivers1
Authors: Slaughter Richard A. , Wiener John D.
Published: March 2007

Abstract:  Water demand in a viable economy tends to be dynamic: it changes over time in response to growth, drought, and social policy. Institutional capacity to re‐allocate water between users and uses under stress from multiple sources is a key concern. Climate change threatens to add to those stresses in snowmelt systems by changing the timing of runoff and possibly increasing the severity and duration of drought. This article examines Snake and Klamath River institutions for their ability to resolve conflict induced by demand growth, drought, and environmental constraints on water use. The study finds that private ownership of water rights has been a major positive factor in successful adaptation, by providing the basis for water marketing and by promoting the use of negotiation and markets rather than politics to resolve water conflict.
Multi‐Criteria Decision Support Systems for Flood Hazard Mitigation and Emergency Response in Urban Watersheds1
Authors: Levy Jason K. , Hartmann Jens , Li Kevin W. , An Yunbi , Asgary Ali
Published: March 2007

Abstract:  Flood management problems are inherently complex, time‐bound and multi‐faceted, involving many decision makers (with conflicting priorities and dynamic preferences), high decision stakes, limited technical information (both in terms of quality and quantity), and difficult tradeoffs. Multi‐Criteria Decision Support Systems (MCDSS) can help to manage this complexity and decision load by combining value judgments and technical information in a structured decision framework. A brief overview of MCDSS is presented, an original MCDSS architecture is put forth, and future research directions are discussed, including extensions to Multi‐Criteria Spatial Decision Support Systems and group MCDSS (as flood management involves shared resources and broad constituencies). With application to the September 11‐12, 2000 Tokai floods in Japan, the proposed multi‐criteria decision support instruments enhance communication among stakeholders and improve emergency management resource allocation. In summary, by making the links among flood knowledge, assumptions and choices more explicit, MCDSS increases stakeholder satisfaction, saves lives, and reduces flood management costs, thereby increasing decision‐making effectiveness, efficiency and transparency.
Residents’ Assessment of an Urban Outdoor Water Conservation Program in Guelph, Ontario1
Authors: Atwood Christine , Kreutzwiser Reid , De Loë Rob
Published: March 2007

Abstract:  Many municipalities have implemented demand management of outdoor water use. Measures such as restrictions on lawn watering and promotion of xeriscaping are effective in reducing water demand during summer months, especially during dry spells. However, little research examines a key factor shaping the success of these programs: residents’ perceptions of and satisfaction with such conservation measures. This article describes an urban outdoor water conservation program in Guelph, Ontario, assesses that program from the perspective of residents, and explores socio‐economic, attitudinal and other factors associated with residents’ assessment of the program. A survey of Guelph residents revealed broad support for the program, which includes restrictions on various outdoor water uses and, under certain circumstances, a ban on lawn watering. However, there was much uncertainty among residents about the effectiveness of the program in reducing water use and the effectiveness of program enforcement. Key factors influencing residents’ assessment of the program were neighborhood, gender and environmental attitude. Implications for the design and implementation of outdoor water conservation programs are discussed, including the importance of better communication of information on program effectiveness and enforcement.
Experimental Investigation of Secondary Flow Structure in a Blade Passage With and Without Leading Edge Fillets
Authors: Mahmood G. I. , Acharya S.
Published: March 2007

Velocity and pressure measurements are presented for a blade passage with and without leading edge contouring in a low speed linear cascade. The contouring is achieved through fillets placed at the junction of the leading edge and the endwall. Two fillet shapes, one with a linear streamwise cross-section (fillet 1) and the other with a parabolic cross-section (fillet 2), are examined. Measurements are taken at a constant Reynolds number of 233,000 based on the blade chord and the inlet velocity. Data presented at different axial planes include the pressure loss coefficient, axial vorticity, velocity vectors, and yaw and pitch angles. In the early stages of the development of the secondary flows, the fillets are seen to reduce the size and strength of the suction-side leg of the horseshoe vortex with associated reductions in the pressure loss coefficients and pitch angles. Further downstream, the total pressure loss coefficients and vorticity show that the fillets lift the passage vortex higher above the endwall and move it closer to the suction side in the passage. Near the trailing edge of the passage, the size and strength of the passage vortex is smaller with the fillets, and the corresponding reductions in pressure loss coefficients extend beyond the mid-span of the blade. While both fillets reduce pressure loss coefficients and vorticity, fillet 1 (linear fillet profile) appears to exhibit greater reductions in pressure loss coefficients and pitch angles.
Large Eddy Simulation of Acoustical Sources in a Low Pressure Axial-Flow Fan Encountering Highly Turbulent Inflow
Authors: Reese Hauke , Kato Chisachi , Carolus Thomas H.
Published: March 2007

A large eddy simulation (LES) was applied to predict the unsteady flow in a low-speed axial-flow fan assembly subjected to a highly “turbulent” inflow that is generated by a turbulence grid placed upstream of the impeller. The dynamic Smagorinsky model (DSM) was used as the subgrid scale (SGS) model. A streamwise-upwind finite element method (FEM) with second-order accuracy in both time and space was applied as the discretization method together with a multi-frame of reference dynamic overset grid in order to take into account the effects of the blade-wake interactions. Based on a simple algebraic acoustical model for axial flow fans, the radiated sound power was also predicted by using the computed fluctuations in the blade force. The predicted turbulence intensity and its length scale downstream of the turbulence grid quantitatively agree with the experimental data measured by a hot-wire anemometry. The response of the blade to the inflow turbulence is also well predicted by the present LES in terms of the surface pressure fluctuations near the leading edge of the blade and the resulting sound power level. However, as soon as the effects of the turbulent boundary layer on the blades become important, the prediction tends to become inaccurate.
Response of Backflow to Flow Rate Fluctuations
Authors: Qiao Xiangyu , Horiguchi Hironori , Tsujimoto Yoshinobu
Published: March 2007

The response of backflow at the inlet of an inducer to the flow rate fluctuation is studied by using three-dimensional numerical calculations based on the k-ϵ turbulence model for the discussion of its effect on cavitation instabilities. It is first shown that the size of the backflow region can be correlated with the angular momentum in the upstream and the phase of the backflow significantly delays behind the quasi-steady response even at a very low frequency. It is then shown that the conservation relation of angular momentum is satisfied with minor effects of the shear stress on the boundary. The supply of the angular momentum by the negative flow is shown to be quasi-steady due to the fact that the pressure difference across the blade causing the backflow is quasi-steady at those frequencies examined. A response function of the angular momentum in the upstream to flow rate fluctuation is derived from the balance of the angular momentum and the results of the numerical calculations. This clearly shows that the backflow responds to the flow rate fluctuation as a first-order lag element. The effects of the backflow cavitation on cavitation instabilities are discussed assuming that the delay of cavity development is much smaller than the delay of the backflow. It was found that the backflow cavitation would destabilize low frequency disturbances due to the effects of the positive mass flow gain factor but stabilize high frequency disturbances due to the effect of the cavitation compliance.
Unsteady Computational Analysis of Vehicle Passing
Authors: Clarke James , Filippone Antonio
Published: March 2007

This paper presents results of the simulation of two vehicles overtaking each other at highways conditions (30m∕s). The simulation was fully unsteady and tracks the maneuver for several body lengths from downstream to upstream. Different mesh strategies have been investigated and assessed. Structured methods with sliding planes have been found the most feasible. The results shown include the effects of relative speed and lateral separation. The passing maneuver is described in detail, and a number of physical phenomena are identified. In particular, the rapid fluid compression and acceleration at the nose passing situation yields a pulse in the drag of the overtaken vehicle. The high pressure bow wave followed swiftly by the low-pressure wake affects the side force and lateral stability at positions slightly different than the nose passing.
Experimental Study on Flow-Induced Disk Flutter Dynamics by Measuring the Pressure Between Disks
Authors: Takada Shigenori , Tagawa Norio , Mori Atsunobu , Mizoh Yoshiaki , Nakakita Masaru
Published: March 2007

It is important to clarify the characteristics of flow-induced vibrations in hard disk drives in order to achieve an ultrahigh magnetic recording density. In particular, it is necessary to reduce the flow-induced disk vibrations referred to as disk flutter. This paper describes the correlation between the disk vibration amplitude and the pressure fluctuation between a pair of high-speed corotating disks. It also reveals the effects of the arm thickness and arm shape on the disk vibrations and the static pressure between the disks. The disk vibrations were measured using a laser Doppler vibrometer (LDV). The static pressure downstream of the arm between a pair of narrow disks was measured by a method in which a side-hole needle was used as a measurement probe. In addition, the direction of air flow along the trailing edge of the arm was measured using a hot-wire anemometer. The experimental results revealed that the arm inserted between the disks suppresses the disk vibrations. However, the shape and thickness of the arm did not quantitatively affect the disk vibrations. The root-mean-square (RMS) static pressure fluctuation downstream of the arm decreased remarkably, whereas the mean static pressure increased when the arm was inserted between the disks. Furthermore, the circumferential variations in both the RMS and mean static pressures reduced when the arm was inserted. Therefore, it is suggested that the disk vibrations are excited by an increase in the static pressure fluctuation, mean dynamic pressure, and circumferential variation in the static pressure between the disks. Consequently, the disk vibrations can be suppressed by inserting the arm or a spoiler.
An Improved Hydrodynamic Model for Open Wet Transmission Clutches
Authors: Yuan Yiqing , Liu Eysion A. , Hill James , Zou Qian
Published: March 2007

A mathematical model describing the hydrodynamics of the flow within a disengaged wet transmission clutch is presented. The primary improvement of this model over the existing ones is the inclusion of the surface tension effect, which is expressed in the pressure equation as an additional term. The drag torque predicted by the model correlates well with the test data for nongrooved clutch packs. The significance of the surface tension in this type of flows is discussed as well.
Performance Assessment of Near‐Surface Facilities for Disposal of Low‐Level Radioactive Waste
Authors: Bashir Sajid
Published: March 2007

Performance Assessment of Near‐Surface Facilities for Disposal of Low‐Level Radioactive Waste NCRP Report No. 152, 468 pp., NCRP Publications, 7910 Woodmound Avenue, Suite 400/Bethesda, MD 20814‐3095; 2006, $75.00. ISBN‐13: 978‐0‐929600‐89‐5, ISBN‐10: 0‐929600‐89‐4.
Evaluation of companding-based spectral enhancement using simulated cochlear-implant processing
Authors: Oxenham Andrew J. , Simonson Andrea M. , Turicchia Lorenzo , Sarpeshkar Rahul
Published: March 2007

This study tested a time-domain spectral enhancement algorithm that was recently proposed by Turicchia and Sarpeshkar [IEEE Trans. Speech Audio Proc. 13, 243–253 (2005)]. The algorithm uses a filter bank, with each filter channel comprising broadly tuned amplitude compression, followed by more narrowly tuned expansion (companding). Normal-hearing listeners were tested in their ability to recognize sentences processed through a noise-excited envelope vocoder that simulates aspects of cochlear-implant processing. The sentences were presented in a steady background noise at signal-to-noise ratios of 0, 3, and 6dB and were either passed directly through an envelope vocoder, or were first processed by the companding algorithm. Using an eight-channel envelope vocoder, companding produced small but significant improvements in speech reception. Parametric variations of the companding algorithm showed that the improvement in intelligibility was robust to changes in filter tuning, whereas decreases in the time constants resulted in a decrease in intelligibility. Companding continued to provide a benefit when the number of vocoder frequency channels was increased to sixteen. When integrated within a sixteen-channel cochlear-implant simulator, companding also led to significant improvements in sentence recognition. Thus, companding may represent a readily implementable way to provide some speech recognition benefits to current cochlear-implant users.
Singular spectrum analysis applied to ultrasonic detection and imaging of brachytherapy seeds
Authors: Mamou Jonathan , Feleppa Ernest J.
Published: March 2007

Ultrasound-guided brachytherapy using titanium-shelled radioactive seeds is a popular, effective means of treating prostate cancer. Unfortunately, implantation using needles inserted transperitoneally causes gland movement and distortion, which often results in seed misplacement and dosimetry errors. If actual seed locations could be determined in the operating room, then corrections to dosimetry errors could be made immediately. However, seed specularity, shadowing, and tissue clutter make imaging seeds difficult using conventional ultrasound. Singular spectrum analysis (SSA) shows promise for reliably imaging radioactive seeds implanted in the prostate and enabling additional corrective implantations to be made in the operating room. SSA utilizes eigenvalues derived from the diagonalized correlation matrix of envelope-detected radio-frequency echo signals to yield a P value indicative of the likelihood of a seed-specific repetitive signal. We demonstrated the potential of SSA for seed detection and imaging and illustrated the trade-off considerations for optimization of SSA in clinical applications using simulations assessing performance as a function of different levels of noise and the presence of repetitive signals with various repetition periods; experiments in an ideal scattering environment; and experiments using seeds implanted in beef.
The Quantum Mechanics of Cohesion
Authors: McWeeny Roy
Published: March 2007

We consider the fundamental problem of "what makes atoms stick together in molecules, crystals, or clusters?" The Heitler and London paper (1927) on the hydrogen molecule marked a first attempt to discuss, in terms of quantum mechanics, the interaction of two atoms with unpaired spins. The aim of this note is to show how the primitive concepts used eighty years ago still retain a certain validity even in a much more general context. We consider in fact the interaction of two arbitrary systems, each with a resultant spin angular momentum, and show how the interaction energy depends on the scalar product of the two resultants. The actual nature of the two systems is irrelevant: they may be atoms, molecules, or ionic species of any kind each described by a wave function which may be, in principle, exact. This provides a first step in the formulation of any general theory of cohesion.
The Absolute Entropies of Alkali Metal Borides. Simple Patterns and High-Level Calculations
Authors: Černušák Ivan , Čukovičová Martina , Asiama Alexandra A. , Gregurick Susan K. , Hoover Paul A. , Tsay Sarah C. , Liebman Joel F.
Published: March 2007

The validity of the recently enunciated average-entropy equation, using symmetry-corrected absolute entropies, was tested against the values obtained from the literature and from accurate quantum chemical calculations. We analyze this validity for the series of yet unexplored alkali metal borides MeB (Me = Li, Na, K, Rb, Cs).
INVESTIGATION OF ELECTRONIC STRUCTURE OF A QUANTUM DOT USING SLATER-TYPE ORBITALS AND QUANTUM GENETIC ALGORITHM
Authors: ÇAKIR BEKİR , ÖZMEN AYHAN , ATAV ÜLFET , YÜKSEL HÜSEYİN , YAKAR YUSUF
Published: March 2007

In this study, electronic properties of a low-dimensional quantum mechanical structure have been investigated by using Genetic Algorithm (GA). One- and two-electron Quantum Dot (QD) systems with an on-center impurity are considerable by assuming the confining potential to be infinitely deep and spherically symmetric. Linear combinations of Slater-Type Orbitals (STOs) were used for the description of the single electron wave functions. The parameters of the wave function of the system were used as individuals in a generation, and the corresponding energy expectation values were used for objective functions. The energy expectation values were determined by using the Hartree-Fock-Roothaan (HFR) method. The orbital exponent ζi's and the expansion coefficient ci's of the STOs were determined by genetic algorithm. The obtained results were compared with the exact result and found to be in a good agreement with the literature.
DYNAMICS OF AVALANCHE ACTIVITIES IN FINANCIAL MARKETS
Authors: KIM CHEOL-HYUN , PARK C. H. , KIM SOO YONG , KIM KYUNGSIK , SCALAS ENRICO
Published: March 2007

We study the dynamical properties of avalanche activities in the Korean Treasury Bond (KTB) futures price and the S&P 500 stock index. We apply the detrended fluctuation analysis, multiscale sample entropy and wavelet coefficient correlation to them, which revealed the scale-free dynamics of the bursting time series, avalanche size, and laminar time. We found that the laminar time and the avalanche size are anti-correlated in a short scale but in a large scale strongly correlated in KTB503, and are strongly correlated over all scales in S&P 500.
TWO-DIMENSIONAL SILICON-BASED PHOTONIC CRYSTAL SLAB WITH PARTIAL AIR-BRIDGE
Authors: TIAN JIE , HAN SHOU-ZHEN , CHENG BING-YING , FENG SHUAI , LI ZHI-YUAN , REN CHENG , ZHANG DAO-ZHONG , JIN AI-ZI
Published: March 2007

We describe a fabrication process of the near-infrared two-dimensional photonic crystal (PC) slab, which is sustained by part of the silica layer underneath the slab and forms a partly air-bridged type. The process involves focused ion beam (FIB) direct write following the selective wet etching of silicon on isolator (SOI) structures. By control the time of dissolving of silica layer in SOI, we successfully fabricated the sample and measured its transmittance spectrum. It is found that the observed spectrum is consistent with the theoretical band structure with FDTD method. For there is partly silica layer remained to support the air-bridge slab, the PC can be fabricated with a large area. If we change the support material under the slab, we might be able to fabricate PC laser with this kind of structure.
NUMERICAL STUDY OF NANOFLUID FLOW AND HEAT TRANSFER IN MICROCHANNELS
Authors: XU DIAO , PAN LUNSHENG
Published: March 2007

It is known that the metal nanoparticles, when dispersed in fluids to form nanofluids, improve the heat conductivity of the fluids. The present paper studies the flow and heat transfer of the nanofluids in a microchannel by using Computational Fluid Dynamic method. It is found that although the nanoparticles enhance the heat transfer of the fluids about certain percent, the nanoparticles also cause a big increase of viscous shear stress on the wall, which causes an increase of the power consumption for driving the nanofluids through the microchannel.