bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling flow control problems under diverse operating conditions by identification and blending of multiple systems
Authors: Kasnakoğlu Coşku
Published: February 2010

In this paper, a dynamical modelling procedure for fluid flow control problems is proposed. The resulting model is simple in that it consists of a number of linear time-invariant systems, but powerful in that it is capable of representing diverse operating conditions within a given flow envelope. The procedure makes use of snapshots of the flow process, which are obtained from experiments or computational fluid dynamics simulations. A proper orthogonal decomposition expansion of the flow is computed from snapshots, and the time coefficients of the expansion are coupled with the input values to form the estimation data. A linear state-space system representing the time coefficients is obtained using subspace system-identification methods. The procedure is repeated for a number of operating points, called breakpoints, which are characterized by one or more flow parameters of interest. The dynamical models obtained at the breakpoints are fused using the output-blending technique. The modelling procedure is illustrated with a flow control case study, where the flow dynamics are governed by the Navier—Stokes equations, the flow parameter of interest is the kinematic viscosity, and the control goal is to regulate the velocity of a given point inside the flow domain.
Transitioning to Middle School in the Sixth Grade: A Hierarchical Linear Modeling (HLM) Analysis of Substance Use, Violence, and Suicidal Thoughts
Authors: Gunter Whitney D. , Bakken Nicholas W.
Published: February 2010

In recent years, public schools have moved away from traditional grade configurations with junior high schools and have shifted toward integrating sixth-grade students into middle schools. It has been argued that the effect this will have on students is to allow for additional freedom and earlier social growth. However, the counterargument to this debate is that these sixth-grade students would then be exposed to an older cohort sooner and, therefore, would be exposed to negative peer influences. This study investigates the behavioral differences between sixth-grade students in elementary schools and their counterparts in middle schools, including suicidal thoughts, violence, and substance abuse. The data used come from the 2007 middle school Delaware Youth Risk Behavior Survey. Results indicate significant differences in suicidal thoughts or actions based on the grade configuration of school they attend, though not in violence or substance use.
Beyond the Shadow of Drugs: Groups with Substance Misusers
Authors: Weegmann Martin , English Christine
Published: February 2010

The myth of Sisyphus speaks to an excruciating cycle of relief and suffering that is central in addiction. This article considers the long shadow cast by drug use, which often constitutes a psychic takeover of personality, with healthier aspects of the self and other interests subsumed by the seductive thrall of intoxication. Such shadows can manifest in groups that promote sober dialogue and eschew anti-dialogue/group process. A means of strengthening psychic muscle, psychodynamic groups are shown to temper the destructive pull towards euphoric or mindless states. In recovery there is a provocative mixing of memory and desire, and recollections of drug highs in groups serve dangerous desires in their enactment of a talking high. Movement towards freedom from drugs, which includes the building of new identities, must be continually fought for. Clinical examples illustrate these points, and point to the devastating impact of addiction in families and the identity voids associated with destructive drinking and drugging.
Decision rules, social norms and the expression of disagreement: the case of qualified-majority voting in the Council of the European Union
Authors: Novak Stéphanie
Published: February 2010

When a group has to make a decision, one can assume that the members’ incentives to state their position vary according to the different decision rules. Decision-making in the Council of the European Union offers an opportunity to study how a decision rule influences the way members of a group state their position. Indeed, in several areas, decisions must be made by qualified-majority voting. But the combination of this rule and of social norms specific to the Council discourages the minority from expressing itself at different stages of decision-making. Decisions seem to be made without opposition at two main stages of the decision-making process: during the plenary sessions, representatives do not vote; according to the official Council records, a high proportion of measures are adopted without opposition.
Samuel Pufendorf: majority rule (logic, justification and limits) and forms of government
Authors: Pasquino Pasquale
Published: February 2010

The article analyses one of the first and more important doctrines of majority rule and its relationship with forms of government, the one presented by Samuel Pufendorf in his De jure naturae et gentium , the most popular work of political theory in the 17th and 18th centuries. It also considers some of the objections raised in the contemporary debate concerning its limits.
Physician Attitudes Regarding Alcohol Use Screening in Older Adult Patients
Authors: Sharp Lindsay , Vacha-Haase Tammi
Published: February 2010

Alcohol use among older adults (65+) is thought to be one of the fastest growing health problems in the country. Although proper assessment and diagnosis is crucial in addressing problem drinking in this population, research suggests that physicians are not adequately screening their older adult patients for alcohol use. The present study examined the relationship between family physicians’ attitudes and perceptions and their screening prevalence with their new and existing older adult patients collected and analyzed in 2007. Results indicated that physicians in the study reported screening 73% of their new patients on intake and 44% of their existing patients. Family physicians with more positive perceptions of their alcohol-management skills with older adults performed more screening with their new and existing older adult patients. Year of medical school graduation was related to screening but only with new patients.
Experimental Study on the Effects of Low Ambient Pressure Conditions at High Altitude on Fire Suppression with Water Mist
Authors: Xin Cai  , Wang Xi-Shi , Liang Tian-Shui , Liao Guang-Xuan
Published: February 2010

In order to study the effects of low ambient pressure conditions at high altitude on fire suppression with water mist, a water mist fire suppression experimental facility was built in Lhasa, Tibet, a province of China. Using this facility, water mist extinguishing tests were carried out on gasoline, diesel oil, molten ghee, and wood crib fires, and the results compared with the similar tests conducted in Hefei. Water mist spray patterns under normal and low atmospheric pressures were characterized with a laser sheet method. Fuel mass burning rates were measured in both Lhasa and Hefei to investigate differences and influences on fire suppression. The experimental results showed that the burning rates of the above fuels are lower in Lhasa than in Hefei, and that mist droplets tended to congregate along the spray cone edge as the atmospheric pressure decreased. For most of the test cases, the fire suppression performance of water mist in Lhasa is a little better than that in Hefei, which may be largely caused by decreasing of the mass burning rate at lower atmospheric pressure conditions.
Enhancing Vocabulary Intervention for Kindergarten Students: Strategic Integration of Semantically Related and Embedded Word Review
Authors: Zipoli Richard P. , Coyne Michael D. , McCoach D. Betsy
Published: February 2010

Two approaches to systematic word review were integrated into an 18-week program of extended vocabulary instruction with kindergarten students from three high-need urban schools. Words in the embedded and semantically related review conditions received systematic and distributed review. In the embedded review condition, brief word definitions were integrated into the narratives of multiple storybooks. In the semantically related review condition, in-depth word review with explicit emphasis on semantic features and associations was provided during extension activities. Systematic review resulted in an almost twofold increase in target word learning. Embedded review was effective and time efficient, whereas semantically related review was time intensive but resulted in higher levels of word learning. There was a significant gain in Peabody Picture Vocabulary Test—III standard scores following the intervention.
Balancing Life as a Nurse in Iran
Authors: Baumann Steven L.
Published: February 2010

The purpose of this column is to provide an introduction to what it is like for nurses in Iran to balance work and family responsibilities.
Disaster Care Through a Humanbecoming Lens
Authors: Hayden Susan J.
Published: February 2010

Hurricane Katrina provided a unique learning experience for a group of senior nursing students from Troy University in Alabama. Using Parse’s teaching-learning processes as a framework, students related their experiences and discovered new meaning for themselves and others as they completed their final semester of the nursing program. This experience exemplified to students that nursing is more than tasks, caring is attentively being with persons, and that holding a hand can demonstrate good nursing care more than a successful intravenous puncture.
Multiple Sclerosis
Authors: Mahdavian Soheyla , Dike Ukamaka , Bryant Alsean , Davison Carina , Ghazvini Patty , Hill Angela
Published: February 2010

Multiple sclerosis, an autoimmune disorder causing the destruction of the impulse carrying myelin sheath of neurons, can be a debilitating and disabling disease. Symptomatic treatment has provided patients with relief through the use of antispasmodics, anticholinergics, and antidepressants, just to name a few, as well as disease treatment by decreasing progression of the illness by treating acute episodes through the use of corticosteroids, interferons, plasmapheresis, and other immunomodulators like glatiramer, mitoxantrone, and natalizumab. With medical advancements and the development of new treatments such as laquinimod, fampridine-SR, and several others, the future looks promising for those living with this illness.
Preconditions for pacts on incomes policy: Bringing structures back in
Authors: Traxler Franz , Brandl Bernd
Published: February 2010

Corporatist theory assumes a close association between centralized structures of interest intermediation and policy concertation, but recent social pacts have occurred in countries without these structures. Recent literature has focused instead on the processes involved in negotiating pacts. We bring structures back into the debate, arguing that tripartite pacts on incomes policy are systematically associated with multi-employer bargaining which is not coordinated by exposed-sector pattern-setting. This thesis is tested on time-series data for 14 West European countries from 1980 to 2003. We conclude by discussing the implications of these findings for the future of pacts.
From Object to Platform
Authors: McQuire Scott , Radywyl Natalia
Published: February 2010

In this article we argue that the upsurge of digital technology in contemporary art practice is requiring artists, art institutions and audiences to engage with time in new ways. Beginning with the way institutions such as New York’s Museum of Modern Art broke with the museological paradigm of only displaying ‘dead’ art, we then examine how the emergence of video art in the 1960s created new practices of time-based spectatorship and altered exhibition protocols. From this vantage, we identify and address a key tendency in the present, namely the move away from conceiving the artwork as a finished object, in favour of the production of open platforms requiring the participation of the public in order to generate their content. We argue that this new setting for art is complex and ambivalent, enabling both new forms of collaboration and social engagement, but also pushing art towards the ‘experience economy’ of commodified leisure.
Latitudinal variation in incidence and type of first central nervous system demyelinating events
Authors: Taylor Bruce V , Lucas Robyn M , Dear Keith , Kilpatrick Trevor J , Pender Michael P , van der Mei Ingrid AF , Chapman Caron , Coulthard Alan , Dwyer Terence , McMichael Anthony J , Valery Patricia C , Williams David , Ponsonby Anne-Louise
Published: February 2010

Increasing prevalence and variable geographic patterns of occurrence of multiple sclerosis suggest an environmental role in causation. There are few descriptive, population-level, data on whether such variability applies to first demyelinating events (FDEs). We recruited 216 adults (18—59 years), with a FDE between 1 November 2003 and 31 December 2006 in a multi-center incident case-control study in four locations on the south-eastern and eastern seaboard of Australia, spanning latitudes 27° south to 43° south. Population denominators were obtained from the Australian Bureau of Statistics censuses of 2001 and 2006. Age and sex adjusted FDE incidence rates increased by 9.55% (95% confidence interval (CI) 7.37—11.78, p < 0.001) per higher degree of latitude. The incidence rate gradient per higher degree of latitude varied by gender (male: 14.69% (95% CI 9.68—19.94, p < 0.001); female 8.13% (95% CI 5.69—10.62, p < 0.001)); and also by the presenting FDE type: optic neuritis 11.39% (95% CI 7.15—15.80, p < 0.001); brainstem/cerebellar syndrome 9.47% (95% CI 5.18—13.93, p < 0.001); and spinal cord syndrome 5.36% (95% CI 1.78—9.06, p = 0.003). Differences in incidence rate gradients were statistically significant between males and females ( p = 0.02) and between optic neuritis and spinal cord syndrome ( p = 0.04). The male to female ratio varied from 1 : 6.7 at 27° south to 1 : 2.5 at 43° south. The study establishes a positive latitudinal gradient of FDE incidence in Australia. The latitude-related factor(s) influences FDE incidence variably according to subtype and gender, with the strongest influence on optic neuritis presentations and for males. These descriptive case analyses show intriguing patterns that could be important for understanding the etiology of multiple sclerosis.
The Paratexts of Inanimate Alice
Authors: Stewart Gavin
Published: February 2010

In her book Writing Machines, N. Katherine Hayles described the concept of the technotext. Hayles used this concept to provide an analysis of a range of texts, including online work, based on their materiality. The analysis described in this article complements this method by developing an approach that explores the conditions of production of contemporary digital literature. It achieves this aim by providing a close reading of the online paratextual elements associated with the first four episodes of Inanimate Alice by Kate Pullinger and Chris Joseph. In doing so, it modifies the print-based analytical framework provide by Gérard Genette and others to develop a detailed account of the off-site, on-site and in-file paratexts of this online work. It sets out a range of thresholds that mould the reception of this text. It also notes how they position it within wider discourses about genre, media, literature and literacy. This article concludes by exploring the limits of this paratextual reading. It discusses whether it provides an adequate account of the material conditions of these texts. It then seeks to integrate this approach into the vision of literary studies described by Hayles in Writing Machines.
Domesticating the mobile in Estonia
Authors: Bolin Göran
Published: February 2010

This article compares the dissemination and usage of mobile phones in post-Soviet, transitional Estonia with patterns in Sweden (a long-time Western democracy). Using a domestication perspective, the study examines the use of voice calls compared with texting by youths (aged 18—24) to probe the role of Estonia’s transition from a state-controlled to a market economy in shaping mobile usage. Results show that while the dissemination of mobiles among young Swedes and Estonians is similar, the patterns of texting and calling are not. In Sweden (as in Japan and even the USA), young people text more than they call, while the reverse is true in Estonia. These findings reflect the fact that unlike Swedes, many Estonians obtained mobile phones before getting landlines, and again unlike Swedes, Estonians are likely to give up landlines in favour of mobiles.
Adherence to vascular protection drugs in diabetic patients in Quebec: a population-based analysis
Authors: Asghari Shabnam , Courteau Josiane , Drouin Catherine , Grégoire Jean-Pierre , Carpentier André C. , Pâquet Mariane , Vanasse Alain
Published: February 2010

The purpose of this study was to assess adherence to vascular protection drugs in diabetic patients using a cohort of diabetic patients aged ≥30 years, covered by the public drug insurance in the province of Quebec, excluding gestational diabetes and patients who were hopitalized or died during the 1-year follow-up. Drug adherence was measured using the medication possession ratio. Multivariate analyses, including logit and multinomial logit were used. Of the 170,381 diabetics (mean age: 62 ± 14 years), 18% and 32% were regular users of ASA and ACEIs/ARBs, respectively. Regular use increased with age (p<0.0001) and comorbidities (p<0.0001). Rural inhabitants were more likely to use ACEIs/ARBs (OR: 1.29; 95% CI: 1.26—1.32) and to be regular users (OR: 1.36; 95% CI: 1.32—1.39). Similar results were found for ASA. In conclusion, despite the high cardiovascular risks associated with diabetes, less than one-third of diabetic adults took vascular-protection drugs regularly. This important issue needs proper attention.
Characterization of rubber particles and rubber chain elongation in Taraxacum koksaghyz
Authors: Schmidt Thomas , Lenders Malte , Hillebrand Andrea , van Deenen Nicole , Munt Oliver , Reichelt Rudolf , Eisenreich Wolfgang , Fischer Rainer , Prüfer Dirk , Gronover Christian Schulze
Published: February 2010

Background

Natural rubber is a biopolymer with exceptional qualities that cannot be completely replaced using synthetic alternatives. Although several key enzymes in the rubber biosynthetic pathway have been isolated, mainly from plants such as Hevea brasiliensis, Ficus spec. and the desert shrub Parthenium argentatum, there have been no in planta functional studies, e.g. by RNA interference, due to the absence of efficient and reproducible protocols for genetic engineering. In contrast, the Russian dandelion Taraxacum koksaghyz, which has long been considered as a potential alternative source of low-cost natural rubber, has a rapid life cycle and can be genetically transformed using a simple and reliable procedure. However, there is very little molecular data available for either the rubber polymer itself or its biosynthesis in T. koksaghyz.

Results

We established a method for the purification of rubber particles - the active sites of rubber biosynthesis - from T. koksaghyz latex. Photon correlation spectroscopy and transmission electron microscopy revealed an average particle size of 320 nm, and 13C nuclear magnetic resonance (NMR) spectroscopy confirmed that isolated rubber particles contain poly(cis-1,4-isoprene) with a purity >95%. Size exclusion chromatography indicated that the weight average molecular mass ("Equation missing"w) of T. koksaghyz natural rubber is 4,000-5,000 kDa. Rubber particles showed rubber transferase activity of 0.2 pmol min-1 mg-1. Ex vivo rubber biosynthesis experiments resulted in a skewed unimodal distribution of [1-14C]isopentenyl pyrophosphate (IPP) incorporation at a "Equation missing"w of 2,500 kDa. Characterization of recently isolated cis-prenyltransferases (CPTs) from T. koksaghyz revealed that these enzymes are associated with rubber particles and are able to produce long-chain polyprenols in yeast.

Conclusions

T. koksaghyz rubber particles are similar to those described for H. brasiliensis. They contain very pure, high molecular mass poly(cis-1,4-isoprene) and the chain elongation process can be studied ex vivo. Because of their localization on rubber particles and their activity in yeast, we propose that the recently described T. koksaghyz CPTs are the major rubber chain elongating enzymes in this species. T. koksaghyz is amenable to genetic analysis and modification, and therefore could be used as a model species for the investigation and comparison of rubber biosynthesis.
SING: Subgraph search In Non-homogeneous Graphs
Authors: Di Natale Raffaele , Ferro Alfredo , Giugno Rosalba , Mongiovì Misael , Pulvirenti Alfredo , Shasha Dennis
Published: February 2010

Background

Finding the subgraphs of a graph database that are isomorphic to a given query graph has practical applications in several fields, from cheminformatics to image understanding. Since subgraph isomorphism is a computationally hard problem, indexing techniques have been intensively exploited to speed up the process. Such systems filter out those graphs which cannot contain the query, and apply a subgraph isomorphism algorithm to each residual candidate graph. The applicability of such systems is limited to databases of small graphs, because their filtering power degrades on large graphs.

Results

In this paper, SING (Subgraph search In Non-homogeneous Graphs), a novel indexing system able to cope with large graphs, is presented. The method uses the notion of feature, which can be a small subgraph, subtree or path. Each graph in the database is annotated with the set of all its features. The key point is to make use of feature locality information. This idea is used to both improve the filtering performance and speed up the subgraph isomorphism task.

Conclusions

Extensive tests on chemical compounds, biological networks and synthetic graphs show that the proposed system outperforms the most popular systems in query time over databases of medium and large graphs. Other specific tests show that the proposed system is effective for single large graphs.
Longitudinal modelling of academic buoyancy and motivation: Do the 5Cs hold up over time?
Authors: Martin Andrew J. , Colmar Susan H. , Davey Louise A. , Marsh Herbert W.
Published: February 2010

Background

Academic buoyancy is students' ability to successfully deal with setbacks and challenges that are typical of academic life. The present study extends previous preliminary cross‐sectional work that tentatively identified five motivational predictors of academic buoyancy – referred to as the ‘5Cs’ of academic buoyancy: confidence (self‐efficacy), coordination (planning), commitment (persistence), composure (low anxiety), and control (low uncertain control).

Aims

The study seeks to more clearly ascertain the effects of motivation (and its mediating role) on academic buoyancy over and above prior academic buoyancy.

Sample

The study comprised N = 1,866 high school students from six schools.

Method

Longitudinal data were collected (1 year apart) and the hypothesized model exploring longitudinal effects was tested using structural equation modelling.

Results

After controlling for prior variance in academic buoyancy, the 5Cs were significant predictors of subsequent academic buoyancy. Furthermore, over and above the direct effects of prior academic buoyancy on subsequent academic buoyancy, the 5Cs significantly mediated this relationship.

Conclusions

The study concludes with a discussion of the substantive, applied, and methodological implications for researchers and practitioners seeking to investigate and address the academic buoyancy of students who require the capacity to effectively function in an ever‐challenging school environment.
Molecular and Cellular Mechanisms Elucidating Neurocognitive Basis of Functional Impairments Associated With Intellectual Disability in Down Syndrome
Authors: Rachidi Mohammed , Lopes Carmela
Published: February 2010

Down syndrome, the most common genetic cause of intellectual disability, is associated with brain disorders due to chromosome 21 gene overdosage. Molecular and cellular mechanisms involved in the neuromorphological alterations and cognitive impairments are reported herein in a global model. Recent advances in Down syndrome research have lead to the identification of altered molecular pathways involved in intellectual disability, such as Calcineurin/NFATs pathways, that are of crucial importance in understanding the molecular basis of intellectual disability pathogenesis in this syndrome. Potential treatments in mouse models of Down syndrome, including antagonists of NMDA or GABAA receptors, and microRNAs provide new avenues to develop treatments of intellectual disability. Nevertheless, understanding the links between molecular pathways and treatment strategies in human beings requires further research.
Correlation Between Methylphenidate and Ritalinic Acid Concentrations in Oral Fluid and Plasma
Authors: Marchei Emilia , Farré Magí , Pardo Ricardo , Garcia-Algar Oscar , Pellegrini Manuela , Pacifici Roberta , Pichini Simona
Published: February 2010

Background: We studied the excretion profile of methylphenidate (MPH) and its metabolite ritalinic acid (RA) in oral fluid and plasma, the oral fluid-to-plasma (OF/P) drug ratio, and the variations of oral fluid pH after drug administration.

Methods: We analyzed oral fluid and plasma samples, obtained from 8 healthy volunteers after ingestion of a single dose of 20 mg fast-release or extended-release MPH, for MPH and RA by LC-MS. We estimated the apparent pharmacokinetic parameters of MPH in plasma and oral fluid and calculated the OF/P ratio for each time interval.

Results: MPH and RA were detected in oral fluid. Whereas parent drug concentrations in oral fluid were an order of magnitude higher than those in plasma, the opposite was observed for RA. Oral fluid concentrations of MPH ranged between 0.5 and 466.7 μg/L and peaked at 0.5 h after administration of the fast-release formulation; they ranged between 0.7 and 89.5 μg/L and peaked at 2 h after administration of the extended-release formulation. Both formulations presented bimodal time-course curves for the OF/P ratio, ranging between 1.8 and 242.1 for the fast-release formulation and between 2.6 and 27.0 for extended-release. Oral fluid pH did not appear to be modified by the administration of the drug, and its influence on OF/P ratio did not affect the correlation of MPH between the 2 body fluids.

Conclusions: The results obtained support the measurement of MPH in oral fluid as an alternative to plasma if the extended-release formulation is used.
Identification of Pathogens by Mass Spectrometry
Authors: Ho Yen-Peng , Reddy P Muralidhar
Published: February 2010

Background: Mass spectrometry (MS) is a suitable technology for microorganism identification and characterization.

Content: This review summarizes the MS-based methods currently used for the analyses of pathogens. Direct analysis of whole pathogenic microbial cells using MS without sample fractionation reveals specific biomarkers for taxonomy and provides rapid and high-throughput capabilities. MS coupled with various chromatography- and affinity-based techniques simplifies the complexity of the signals of the microbial biomarkers and provides more accurate results. Affinity-based methods, including those employing nanotechnology, can be used to concentrate traces of target microorganisms from sample solutions and, thereby, improve detection limits. Approaches combining amplification of nucleic acid targets from pathogens with MS-based detection are alternatives to biomarker analyses. Many data analysis methods, including multivariate analysis and bioinformatics approaches, have been developed for microbial identification. The review concludes with some current clinical applications of MS in the identification and typing of infectious microorganisms, as well as some perspectives.

Summary: Advances in instrumentation (separation and mass analysis), ionization techniques, and biological methodologies will all enhance the capabilities of MS for the analysis of pathogens.
Carnivoran dental microwear textures: comparability of carnassial facets and functional differentiation of postcanine teeth
Authors: Ungar Peter S. , Scott Jessica R. , Schubert Blaine W. , Stynder Deano D.
Published: February 2010

No abstract available
Food Porn
Authors: mcbride anne e.
Published: February 2010

Since the term first appeared, food porn has typically referred to watching others cook on television or gazing at unattainable dishes in glossy magazines without actually cooking oneself. This forum seeks to revisit this notion of food porn that is mostly taken for granted in both popular and scholarly literature. It offers a brief perspective of the appearance and use of the term food porn to examine how it came to be a term used mostly by commentators rather than by people actively engaged in the world of cooking. Practitioners (chefs and a food television producer) and academics address whether or not food porn exists, what shape it might take, what purpose it might serve, and/or what usefulness it might have, showing that these contentious issues are more complex than the ease with which the term is used might let on.
A System Dynamics Model for Planning Cardiovascular Disease Interventions
Authors: Hirsch Gary , Homer Jack , Evans Elizabeth , Zielinski Ann
Published: February 2010

Planning programs for the prevention and treatment of cardiovascular disease (CVD) is a challenge to every community that wants to make the best use of its limited resources. Selecting programs that provide the greatest impact is difficult because of the complex set of causal pathways and delays that link risk factors to CVD. We describe a system dynamics simulation model developed for a county health department that incorporates and tracks the effects of those risk factors over time on both first-time and recurrent events. We also describe how the model was used to evaluate the potential impacts of various intervention strategies for reducing the county's CVD burden and present the results of those policy tests.
When Intraclass Correlation Coefficients Go Awry: A Case Study From a School-Based Smoking Prevention Study in South Africa
Authors: Resnicow Ken , Zhang Nanhua , Vaughan Roger D. , Reddy Sasiragha Priscilla , James Shamagonam , Murray David M.
Published: February 2010

Objectives. We conducted a group randomized trial of 2 South African school-based smoking prevention programs and examined possible sources and implications of why our actual intraclass correlation coefficients (ICCs) were significantly higher than the ICC of 0.02 used to compute initial sample size requirements.

Methods. Thirty-six South African high schools were randomly assigned to 1 of 3 experimental groups. On 3 occasions, students completed questionnaires on tobacco and drug use attitudes and behaviors. We used mixed-effects models to partition individual and school-level variance components, with and without covariate adjustment.

Results. For 30-day smoking, unadjusted ICCs ranged from 0.12 to 0.17 across the 3 time points. For lifetime smoking, ICCs ranged from 0.18 to 0.22; for other drug use variables, 0.02 to 0.10; and for psychosocial variables, 0.09 to 0.23. Covariate adjustment substantially reduced most ICCs.

Conclusions. The unadjusted ICCs we observed for smoking behaviors were considerably higher than those previously reported. This effectively reduced our sample size by a factor of 17. Future studies that anticipate significant cluster-level racial homogeneity may consider using higher-value ICCs in sample-size calculations to ensure adequate statistical power.
Tuberculosis Transmission and Use of Methamphetamines in Snohomish County, WA, 1991–2006
Authors: Pevzner Eric S. , Robison Susan , Donovan Jenny , Allis Donna , Spitters Chris , Friedman Rachel , Ijaz Kashef , Oeltmann John E.
Published: February 2010

Objectives. We investigated a cluster of tuberculosis (TB) cases among persons using methamphetamines in Snohomish County, Washington, to determine the extent of the outbreak, examine whether methamphetamine use contributed to TB transmission, and implement strategies to prevent further infections.

Methods. We screened contacts to find and treat persons with TB disease or infection. We then formed a multidisciplinary team to engage substance abuse services partners and implement outreach strategies including novel methods for finding contacts and a system of incentives and enablers to promote finding, screening, and treating patients with TB and their infected contacts.

Results. We diagnosed and completed treatment with 10 persons with TB disease. Eight of 9 adult patients and 67% of their adult contacts reported using methamphetamines. Of the 372 contacts, 319 (85.8%) were screened, 80 (25.1%) were infected, 71 (88.8%) started treatment for latent infection, and 57 (80.3%) completed treatment for latent infection.

Conclusions. Collaborative approaches integrating TB control, outreach, incentives, and enablers resulted in high rates of treatment adherence and completion among patients and infected contacts. TB control programs should collaborate with substance abuse programs to address addiction, overcome substance abuse–related barriers to treatment, treat TB, and prevent ongoing transmission.
Promoters and Barriers to Fruit, Vegetable, and Fast-Food Consumption Among Urban, Low-Income African Americans—A Qualitative Approach
Authors: Lucan Sean C. , Barg Frances K. , Long Judith A.
Published: February 2010

To identify promoters of and barriers to fruit, vegetable, and fast-food consumption, we interviewed low-income African Americans in Philadelphia. Salient promoters and barriers were distinct from each other and differed by food type: taste was a promoter and cost a barrier to all foods; convenience, cravings, and preferences promoted consumption of fast foods; health concerns promoted consumption of fruits and vegetables and avoidance of fast foods. Promoters and barriers differed by gender and age. Strategies for dietary change should consider food type, gender, and age.
A Framework for Public Health Action: The Health Impact Pyramid
Authors: Frieden Thomas R.
Published: February 2010

A 5-tier pyramid best describes the impact of different types of public health interventions and provides a framework to improve health. At the base of this pyramid, indicating interventions with the greatest potential impact, are efforts to address socioeconomic determinants of health. In ascending order are interventions that change the context to make individuals' default decisions healthy, clinical interventions that require limited contact but confer long-term protection, ongoing direct clinical care, and health education and counseling.

Interventions focusing on lower levels of the pyramid tend to be more effective because they reach broader segments of society and require less individual effort. Implementing interventions at each of the levels can achieve the maximum possible sustained public health benefit.
Economic and social burden due to injuries and violence in Nepal: A cross-sectional study
Authors: Joshi SK , Shrestha S
Published: February 2010

Background: Injury and violence cause five million deaths annually in the world which is around 9% of the global mortality. Eight out of fifteen leading causes of deaths in the age group 15-25 years are injury related. Objective: The objective of this study was to assess the incidence, severity and socio-economic burden of injuries and violence in two cities of Nepal. Materials and methods: Relevant data was collected from 17th August 2008 to 16th September 2008 from injured patients attending emergency departments at six health centres in two cities. Results: In total, 505 injury cases were reported. 42.5% of the injuries occurred in roads and 34.1% at home. 65% of road traffic injuries involved motorcycles. The majority (60%) of the injured subjects were economically active. A single injury case cost 126.2 US$ including all the expenses and the loss due to inability to work. Conclusion: The high incidence of injuries, especially road traffic injuries, adds a huge economic burden to nation. Key words: disabilities; economic burden; injuries; violence DOI: 10.3126/kumj.v7i4.2752 Kathmandu University Medical Journal (2009) Vol.7, No.4 Issue 28, 344-350
Stereotactic radiosurgery for symptomatic solitary cerebral cavernous malformations considered high risk for resection
Authors: Lunsford L. Dade , Khan Aftab A. , Niranjan Ajay , Kano Hideyuki , Flickinger John C. , Kondziolka Douglas
Published: February 2010

Object

A retrospective study was conducted to reassess the benefit and safety of stereotactic radiosurgery (SRS) in patients with solitary cerebral cavernous malformations (CCMs) that bleed repeatedly and are poor candidates for surgical removal.

Methods

Between 1988 and 2005 at the University of Pittsburgh, the authors performed SRS in 103 evaluable patients (57 males and 46 females) with solitary symptomatic CCMs. The mean patient age was 39.3 years. Ninety-eight percent of these patients had experienced 2 or more hemorrhages associated with new neurological deficits. Seventeen patients (16.5%) had undergone attempted resection before radiosurgery. Ninety-three CCMs were located in deep brain structures and 10 were in subcortical lobar areas of functional brain importance. The median malformation volume was 1.31 ml, and the median tumor margin dose was 16 Gy.

Results

The follow-up ranged from 2 to 20 years. The annual hemorrhage rate—that is, a new neurological deficit associated with imaging evidence of a new hemorrhage—before SRS was 32.5%. After SRS 22 hemorrhages were observed within 2 years (10.8% annual hemorrhage rate) and 4 hemorrhages were observed after 2 years (1.06% annual hemorrhage rate). The risk of hemorrhage from a CCM was significantly reduced after radiosurgery (p < 0.0001). Overall, new neurological deficits due to adverse radiation effects following SRS developed in 14 patients (13.5%), with most occurring early in our experience. Modifications in technique (treatment volume within the T2-weighted MR imaging–defined margin, use of MR imaging, and dose reduction for CCM in critical brainstem locations) further reduced risks after SRS.

Conclusions

Data in this study provide further evidence that SRS is a relatively safe procedure that reduces the rebleeding rate for CCMs located in high-surgical-risk areas of the brain.
Fractured Governance and Local Frictions: The Exclusionary Nature of a Clandestine Land Market in Southern Zambia
Authors: Sitko Nicholas J.
Published: February 2010

This article explores the ways in which efforts to expand private land tenure, coupled with the continued centrality of customary land administration in Zambia, produce a fractured system of land governance in which localized markets for land emerge but are forced to operate in a clandestine manner. Using ethnographic and archival data sources, I argue that despite the historical and contemporary relationship between land rights and economic ‘development’, the clandestine nature of land markets in rural Zambia tends to (re)produce many of the social ills that ‘development’ seeks to resolve. Using a case study of a clandestine market for land in a Tonga-speaking region of southern Zambia, this article shows how these markets undermine women's rights to land, while allowing for the consolidation of wealth and power in the hands of a few.
The Effects of Previous Abdominal Operations and Intraperitoneal Adhesions on the Outcome of Peritoneal Dialysis Catheters
Authors: Keshvari Amir , Fazeli Mohammad Sadegh , Meysamie Alipasha , Seifi Sepideh , Taromloo Mohammad Kazem Nouri
Published: February 2010

Background

Patients with previous history of abdominal operations are sometimes excluded from consideration for peritoneal dialysis because of concerns for increased risk of complications during the implantation procedure and inadequate dialysis due to reduced peritoneal surface area. Employing a laparoscopic approach, we compared the outcome of peritoneal dialysis catheters in 2 groups of patients with and without intra-abdominal adhesions.

Methods

All data in this report were recorded prospectively. Revision-free and overall survival of catheters, the incidence of mechanical and infectious complication, and surgical revision rates were compared between the 2 groups.

Results

In 217 successful catheter implantations, there was a history of previous abdominal surgery in 42.9% of procedures; only 26.9% of them had intraperitoneal adhesions; 2.8% of patients without history of previous abdominal surgery had intraperitoneal adhesions. There were no significant differences between the 2 groups for 1- and 2-year revision-free and overall catheter survival, mechanical dysfunction, infectious complications, or surgical revision rates.

Conclusion

History of previous abdominal surgery should not be used to judge the eligibility of patients for peritoneal dialysis. Laparoscopic placement is the best way to ensure optimal catheter outcomes equivalent to patients without previous abdominal surgery.
Angiotensin Receptor Blocker Telmisartan Improves Insulin Sensitivity in Peritoneal Dialysis Patients
Authors: Cioni Antonio , Sordini Caterina , Cavallini Ivo , Bigazzi Roberto , Campese Vito M.
Published: February 2010

Background

Insulin resistance (IR) is common among patients on dialysis and is worse among patients on peritoneal dialysis (PD) than among patients on hemodialysis. In this study we tested the hypothesis that administration of telmisartan, an angiotensin II type 1 receptor antagonist, might improve insulin sensitivity in patients on PD.

Method

This was a crossover study of 30 nondiabetic patients with end-stage renal disease being treated with PD. Group A patients ( n = 15) received telmisartan and other antihypertensive drugs for 4 months, followed by 4 months without telmisartan. Group B patients ( n = 15) received their usual treatment for 4 months, followed by 4 months of treatment with telmisartan. Blood glucose and serum insulin levels were monitored and homeostasis model assessment method for IR (HOMA-IR) was calculated.

Results

Treatment with telmisartan had no significant impact on serum glucose, potassium, and bicarbonate levels. However, telmisartan significantly reduced serum insulin levels and the HOMA index in groups A and B.

Conclusion

This study demonstrated that telmisartan, an angiotensin receptor type 1 antagonist, may effectively improve insulin sensitivity as measured by HOMA in patients treated with PD.
Hydrothorax: Pleural Effusion Associated with Peritoneal Dialysis
Authors: Lew Susie Q.
Published: February 2010

Hydrothorax in a patient treated with peritoneal dialysis (PD) poses a diagnostic dilemma. Hydrothorax due to migration of dialysis fluid across the diaphragm and into the pleural space creates a serious complication of PD but generally does not threaten life. Shortness of breath causes the patient to seek medical attention. A sudden diminution in dialysis adequacy or poor ultrafiltration rate constitutes a unique marker for patients treated with PD compared to the general population. This article reviews the etiology for hydrothorax specifically in the PD population. Thoracentesis with chemical analysis of the fluid, imaging studies with and without contrast or markers, and video-assisted thoracoscopic surgery play important roles in the evaluation of hydrothorax. A conservative PD regimen, surgical intervention, and pleurodesis provide treatment options to those receiving PD.
Peritoneal Dialysis after Nonrenal Solid Organ Transplantation: Clinical Outcomes and Practical Considerations
Authors: Perl Jeffrey , Bargman Joanne M. , Jassal Sarbjit V.
Published: February 2010

The incidence of end-stage renal disease following nonrenal solid organ transplantation (NRSOT) is increasing and is associated with a poor prognosis. The etiology of end-stage renal disease is multifactorial, with calcineurin inhibitor (CNI) nephrotoxicity being primarily responsible. The impact of dialysis modality on the survival of these patients remains unclear. Peritoneal dialysis appears to be a feasible and safe option for renal replacement therapy in NRSOT patients. Concerns that NRSOT patients are at a higher risk of infectious and noninfectious complications necessitate practical considerations when prescribing and planning for peritoneal dialysis in these patients. While nephrotoxicity is a well-recognized complication of long-term CNI use, “peritoneotoxic” effects with significant alterations in peritoneal membrane structure and function have recently been described. Further study including the role of CNI-free immunotherapy protocols to optimize the outcomes of NRSOT recipients is needed.
Comparison of the Multiple-Aliquot and Batch Methods of Monitoring Peritoneal Dialysis Adequacy in Patients
Authors: Lyon Andrew W. , James Janice , Lemaire Christine , Culleton Bruce
Published: February 2010

Background

Effluent fluid is analyzed to determine Kt/V urea and creatinine clearance as measures of adequacy of peritoneal dialysis. To avoid the physical mixing of fluids and to minimize handling of full effluent bags, a multiple-aliquot method of sampling was developed and compared to the traditional batch method.

Methods

The batch method and the multiple-aliquot method were performed for 31 consecutive patients. Pooled fluid urea and creatinine measurements were determined for each method. PD Adequest 2.0 (Baxter Healthcare, Deerfield, IL, USA) was used to derive calculated peritoneal dialysis parameters.

Results

Urea dialysate levels, calculated weekly urea clearances, protein catabolic rate, and Kt/V were not statistically different ( p > 0.05) between the 2 methods. Dialysate creatinine and creatinine clearance with the 2 methods were statistically distinct but the differences were not clinically important. The processing time per set of patient effluent bags was reduced from 45 to 18 minutes, handling of the bags was minimized, and error associated with inadequate mixing of pooled fluids was avoided.

Conclusion

The multiple-aliquot method generates accurate and timely results to assess peritoneal dialysis prescription adequacy while reducing staff effort.