bluuebunny/crossref_metadata_2025 huggingface dataset:
Mutational Analysis of CLC-5, Cofilin and CLC-4 in Patients with Dent’s Disease
Authors: Wu Fiona , Reed Anita A.C. , Williams Sian E. , Loh Nellie Y. , Lippiat Jonathan D. , Christie Paul T. , Large Oliver , Bettinelli Alberto , Dillon Michael J. , Goldraich Noemia P. , Hoppe Bernd , Lhotta Karl , Loirat Chantal , Malik Rayaz , Morel Delphine , Kotanko Peter , Roussel Bernard , Rubinger Dvora , Schrander-Stumpel Connie , Serdaroglu Erkin , Nesbit M. Andrew , Ashcroft Frances , Thakker Rajesh V.
Published: June 2009

Background/Aims: Dent’s disease is caused by mutations in the chloride/proton antiporter, CLC-5, or oculo-cerebro-renal-syndrome-of-Lowe (OCRL1) genes. Methods: Eighteen probands with Dent’s disease were investigated for mutations in CLC-5 and two of its interacting proteins, CLC-4 and cofilin. Wild-type and mutant CLC-5s were assessed in kidney cells. Urinary calcium excretion following an oral calcium challenge was studied in one family. Results: Seven different CLC-5 mutations consisting of two nonsense mutations (Arg347Stop and Arg718Stop), two missense mutations (Ser244Leu and Arg516Trp), one intron 3 donor splice site mutation, one deletion-insertion (nt930delTCinsA) and an in-frame deletion (523delVal) were identified in 8 patients. In the remaining 10 patients, DNA sequence abnormalities were not detected in the coding regions of CLC-4 or cofilin, and were independently excluded for OCRL1. Patients with CLC-5 mutations were phenotypically similar to those without. The donor splice site CLC-5 mutation resulted in exon 3 skipping. Electrophysiology demonstrated that the 523delVal CLC-5 mutation abolished CLC-5-mediated chloride conductance. Sixty percent of women with the CLC-5 deletion-insertion had nephrolithiasis, although calcium excretion before and after oral calcium challenge was similar to that in unaffected females. Conclusions: Three novel CLC-5 mutations were identified, and mutations in OCRL1, CLC-4 and cofilin excluded in causing Dent’s disease in this patient cohort.
Pro-Inflammatory Cytokine Genes Influence the Clinical Features of Frontotemporal Lobar Degeneration
Authors: Rainero Innocenzo , Rubino Elisa , Cappa Giorgetta , Rota Eugenia , Valfrè Walter , Ferrero Patrizia , Fenoglio Pierpaola , Baci Denisa , D’Amico Giuseppina , Vaula Giovanna , Gallone Salvatore , Pinessi Lorenzo
Published: June 2009

Background/Aims: Recent studies suggested a role for pro-inflammatory mediators in frontotemporal lobar degeneration (FTLD). The objective of this study was to evaluate the association of functionally active polymorphisms in pro-inflammatory cytokine genes with the occurrence and the clinical features of the disease. Methods: Using a case-control study, we compared allelic and genotypic frequencies of several polymorphisms in the interleukin (IL)-1α, interleukin (IL)-1β, interleukin (IL)-6 and tumor necrosis factor (TNF)-α genes between 110 FTLD patients and 119 healthy controls. Results: No significant association between the examined polymorphisms and the disease was found. However, in comparison with remaining genotypes, patients carrying the T/T genotype of the IL-1β gene showed a significantly lower age at onset of the disease. In addition, scores of the Frontal Assessment Battery were significantly modified by the IL-6 –174G>C polymorphism. Conclusion: Our findings support a role for pro-inflammatory cytokine genes in the pathogenesis of frontotemporal lobar degeneration.
Antimesenteric Tapering Enteroplasty in an Adult Patient with Clinical Evidence of Obstruction: A Bowel-Preserving Alternative to Resection
Authors: Lavotshkin S. , Savel R.H. , Theilen T.M. , Shlasko E. , Chorost M.I.
Published: June 2009

Background/Aims: The approach to small bowel obstruction, when unrelieved with medical management, is open or laparoscopic exploration, often necessitating lysis of adhesions and the resection of any compromised bowel. In patients with prior bowel resections, the surgeon must tread a fine line, so as not to precipitate the clinical derangement known as short bowel syndrome (SBS). Techniques have been described that curtail the extent of intestinal resection, but these are primarily limited to the pediatric literature and are not commonly practiced in the general surgical population. Methods: We report a case of a complicated small bowel obstruction in a patient with pre-existing short bowel length, in which a tapering enteroplasty was performed. Results: Antimesenteric tapering successfully achieved a return of bowel function, avoiding the morbidity of an extended small bowel resection and the possibility of developing SBS. Conclusion: In such patients who are at high risk of developing SBS, in whom a segment of dilated small bowel has become defunctionalized, leading to significant and life-threatening symptoms, this procedure has the potential to help prevent SBS and its lifelong complications and associated mortality.
Small Cell Carcinoma with Paraneoplastic Polyneuropathy and Tumor Embolization: A Case Report and Literature Review
Authors: Sodhi Manica , Stoller James K.
Published: June 2009

Although small cell cancer of the lung may have protean manifestations, tumor embolization and inability to identify the primary sites are unusual features. We present a patient with anti-Hu antibody-associated paraneoplastic sensory polyneuropathy and tumor embolism diagnosed by endovascular biopsy to be due to small cell cancer, the primary site of which was not evident. To our knowledge, this patient represents only the second individual to be described with tumor embolization complicating small cell cancer and reminds clinicians of the extended spectrum of this disease.
A Comparison of Mycophenolate Mofetil with Ciclosporine for the Treatment of Chronic Plaque-Type Psoriasis
Authors: Beissert Stefan , Pauser Sylvia , Sticherling Michael , Frieling Uta , Loske Klaus-Dieter , Frosch Peter J. , Haase Ingo , Luger Thomas A.
Published: June 2009

Aims: To compare the efficacy of ciclosporine (CsA) versus mycophenolate mofetil (MMF) in psoriasis, a randomized trial was conducted. Methods: A prospective multicenter randomized open-label clinical trial was performed to compare two parallel groups of patients with chronic plaque psoriasis undergoing different treatments. Therefore, a total of 54 patients with psoriasis were randomly assigned to treatment with either CsA (2.5 mg/kg body weight) or MMF (2 g daily) for 12 weeks, and the drug doses were adjusted according to response. The psoriasis area and severity index (PASI) was used to assess the clinical severity of psoriasis. The primary outcome of this trial was the time to disease relapse. Safety, PASI scores and psoriasis disability index (PDI) were assessed as secondary outcome. Results: There was no difference in time to disease relapse between the two groups. After 12 weeks of treatment, the mean PASI score (±SD) decreased from 24.6 ± 11.1 to 6.6 ± 7.3 in the CsA group (n = 27) and from 22.4 ± 9.2 to 10.6 ± 6.7 in the MMF group (n = 27; p = 0.02). The side effects, time to remission and PDI were similar in both groups. Conclusions: After 12 weeks, CsA demonstrated a significantly superior efficacy in psoriasis compared to MMF.
Scaling of Precipitation Extremes over a Wide Range of Climates Simulated with an Idealized GCM
Authors: O’Gorman Paul A. , Schneider Tapio
Published: June 2009

Extremes of precipitation are examined in a wide range of climates simulated with an idealized aquaplanet GCM. The high percentiles of daily precipitation increase as the climate warms. Their fractional rate of increase with global-mean surface temperature is generally similar to or greater than that of mean precipitation, but it is less than that of atmospheric (column) water vapor content. A simple scaling is introduced for precipitation extremes that accounts for their behavior by including the effects of changes in the moist-adiabatic lapse rate, the circulation strength, and the temperature when the extreme events occur. The effects of changes in the moist-adiabatic lapse rate and circulation strength on precipitation extremes are important globally, whereas the difference in the mean temperature and the temperature at which precipitation extremes occur is important only at middle to high latitudes.
Investigating Possible Links between Incoming Cosmic Ray Fluxes and Lightning Activity over the United States
Authors: Chronis Themis G.
Published: June 2009

During the past two decades, particular scientific attention has been drawn to the potential cosmic ray–atmospheric coupling. Galactic cosmic rays reaching the upper troposphere are suggested as the key modulators of the global electric circuit, with further implications on cloud microphysical processes. Unfortunately, the scarcity of the associated observations renders the evaluation of the theoretical mechanisms rather difficult. This contribution proposes a different approach by introducing observations provided by the National Lightning Detection Network for the period 1990–2005. The study area encompasses the greater part of continental United States and the surrounding waters. The results highlight a statistically significant positive trend between monthly lightning activity and galactic cosmic ray fluxes during the winter season. During the summer season, the trend becomes statistically nonsignificant. In addition, the featured analysis introduces a technique to assess the potential impact of Forbush events on daily lightning activity. Results illustrate that lightning activity may be responsive (minimized) 4–5 days after a Forbush event.
Southern Africa Summer Drought and Heat Waves: Observations and Coupled Model Behavior
Authors: Lyon Bradfield
Published: June 2009

Observations of daily maximum temperature (Tx) and monthly precipitation and their counterpart fields from three coupled models from the Coupled Model Intercomparison Project Phase 3 (CMIP3) archive have been used for exploratory research into the behavior of heat waves, drought, and their joint occurrence across the southern Africa subcontinent. The focus is on seasonal drought and heat waves during austral summer [December–February (DJF)] for land areas south of 15°S. Observational results (Tx available only for South Africa) are compared with those based on CMIP3 twentieth-century climate runs for a common analysis period of 1961–2000 while climate projections for the twenty-first century are also considered using the Special Report on Emissions Scenarios (SRES) A1B forcing scenario. Heat waves were defined when daily Tx values exceeded the 90th percentile for at least 3 consecutive days, while drought was identified via a standardized index of seasonal precipitation. When assessed over the entire study domain the unconditional probability of a heat wave, and its conditional probability given drought conditions, were similar in the models and (for a smaller domain) observations. The models exhibited less ability in reproducing the observed conditional probability of a heat wave given El Niño conditions. This appears to be related to a comparatively weak seasonal precipitation teleconnection pattern into southern Africa in the models during El Niño when drought conditions often develop. The heat wave–drought relationship did not substantially change in climate projections when computing anomalies from future climate means. However, relative to a 1981–2000 base period, the probability of a heat wave increases by over 3.5 times relative to the current climate. Projections across the three models suggest a future drying trend during DJF although this was found to be a model-dependent result, consistent with other studies. However, a decreasing trend in the evaporative fraction was identified across models, indicating that evaluation of future drought conditions needs to take into account both the supply (precipitation) and demand (evaporation) side of the surface water balance.
A Multiscale Ensemble Filtering System for Hydrologic Data Assimilation. Part II: Application to Land Surface Modeling with Satellite Rainfall Forcing
Authors: Pan Ming , Wood Eric F.
Published: June 2009

Part I of this series of studies developed procedures to implement the multiscale filtering algorithm for land surface hydrology and performed assimilation experiments with rainfall ensembles from a climate model. However, a most important application of the multiscale technique is to assimilate satellite-based remote sensing observations into a land surface model—and this has not been realized. This paper focuses on enabling the multiscale assimilation system to use remotely sensed precipitation data. The major challenge is the generation of a rainfall ensemble given one satellite rainfall map. An acceptable rainfall ensemble must contain a proper multiscale spatial correlation structure, and each ensemble member presents a realistic rainfall process in both space and time. A pattern-based sampling approach is proposed, in which random samples are drawn from a historical rainfall database according to the pattern of the satellite rainfall and then a cumulative distribution function matching procedure is applied to ensure the proper statistics for the pixel-level rainfall intensity. The assimilation system is applied using Tropical Rainfall Measuring Mission real-time satellite rainfall over the Red–Arkansas River basin. Results show that the ensembles so generated satisfy the requirements for spatial correlation and realism and the multiscale assimilation works reasonably well. A number of limitations also exist in applying this generation method, mainly stemming from the high dimensionality of the problem and the lack of historical records.
First Eurasia Emerging Markets Forum
Authors: Linn Johannes F.
Published: June 2009

Eurasia, along with Africa, is the last big frontier of global integration. While the last two centuries were marked by rapid economic integration across the Atlantic and Pacific oceans, there is still need for a catch-up across the vast continental space encompassing Europe and Asia (Eurasia). Central Asia is centrally located in this super-continent. Its development will be one of the critical factors for the effective integration of Eurasia. At the same time, Eurasian economic integration represents a major opportunity for Central Asia, as it moves from being a land-locked region far from markets to one positioned at the core of a dynamic and rapidly connecting economic space with access to the major new markets and sources of finance, knowledge and power in the world.

The article explores six issues: ( i) How severe is the current global financial and economic crisis and its impact on Central Asia? ( ii) What are the implications of the Eurasian economic integration process? ( iii) What are Central Asia's need and potential for economic integration and cooperation? ( iv) How to reap maximum benefits from Central Asia's energy and water resources for the countries in the region? ( v) How to facilitate trade and transit within the region and with the major neighbours? And, what can be done to improve the private business climate in Central Asia?
Business Opportunities in Africa for CDM Projects and Carbon Trading
Authors: Jeker Rolf M.
Published: June 2009

This paper complements the parallel paper by Ramos and Kahla on the policy and business implications of climate change for Africa. This paper outlines, in language understandable to a lay reader, the background to and mechanisms related to Clean Development Mechanism (CDM). TCDM is the major international initiative to provide incentives to private companies and countries to develop and implement projects aimed at reducing carbon emissions at the global level and thus mitigating climate change by transferring financial resources across national boundaries through a market mechanism.

It then explores opportunities and challenges for Africa, including the political, technical, financial and legal barriers that have prevented Africa until now from participating and benefitting adequately from the CDM and similar other international financial mechanisms. To illustrate the issues concretely, it presents a case study of past efforts in Kenya to participate in the CDM. It then suggests possible ways to improve Africa's access to CDM markets in the future as well as practical steps private businesses can take to benefit from CDM and private markets in carbon trading. It argues that given inadequate public policy attention so far, African private sector needs to play a much stronger role perhaps in partnership with experienced players from the outside.
Older Adult Safety and Mobility
Authors: Eby David W. , Molnar Lisa J.
Published: June 2009

In the coming decades, about one in five drivers will be aged 65 or more years in many Western nations. Given the increased fatal crash risk of older adults coupled with the continuing need for effective mobility, the issue of older adult safety and mobility is complex. Indeed, researchers have suggested that this issue has two interdependent, underlying goals for research and programs: to help those who are able to drive safely continue to do so and to identify and provide community mobility support to those who are no longer able to drive. This article briefly discusses the issues and research needs related to older adult safety and mobility including population and driving trends, crash risks, skills needed for safe driving, the effects of medical conditions and medicines on driving skills, screening and assessment, strategies for extending safe driving, and driving cessation and the use of alternative transportation options.
Immigrants and Travel Demand in the United States
Authors: Chatman Daniel G. , Klein Nicholas
Published: June 2009

Immigrants account for a majority of recent urban population growth in the United States, and for much economic growth as well. This is expected to continue for the next several decades. The foreign-born are much more likely to use transit, carpool, walk, and bicycle, particularly in their first few years of living in the United States. These trends represent challenges and opportunities for transportation and land use planners to increase the environmental sustainability of population growth, use existing transportation systems to their maximum efficiency, and support economic development. But doing so depends on anticipating the travel demands of varying immigrant groups, and those demands in turn depend on their employment and residential location choices. The authors present the most current data available on these trends, summarize research literature, and identify the major research questions needing answers to understand how to accommodate the travel demands of immigration-driven population growth.
Sex Changes Everything
Authors: Crane Randall , Takahashi Lois
Published: June 2009

The average U.S. male historically commutes further and longer than his female counterpart. Yet pivotal changes at home, as younger women especially increase their influence on household location and work decisions, and in the labor market, and as women's participation rates and profiles approach men's, strongly suggest that gender's influence on travel might be changing as well. Furthermore, the independent and interactive influence of other demographic factors, not least age and race, remain unclear. This study analyzes national microdata covering the past 20 years to examine both issues. We find sources of both convergence and divergence in travel behaviors by sex. The gender gap in commute length of older workers is growing, even while that of younger workers steadily closes. At the same time, racial differences in mode choice and commute times are becoming less pronounced—both by race and by gender. Thus, gendered elements of travel demand are indeed evolving, if not in predictable directions.
Longevity, Lifestyle, and Anticipating the New Demands of Aging on the Transportation System
Authors: Coughlin Joseph F.
Published: June 2009

The baby boomers, 77 million people born between 1946 and 1964, are the single largest generation in American history. They have changed the face of the United States while placing new demands on the transportation sector. Today, America's “youth generation” is aging. Although older driver safety is a perennial issue, this article does not address this topic; instead, the focus is on the following: Who are the baby boomers, how are they different from previous generations of older people, and what difference does it make for transportation? What will they be doing in old age? Where will they live, and how will they get around? What role might new technologies play in their mobility? What does their retirement mean for the transportation workforce in both government and industry? This article identifies key transportation research questions, policy issues, and practical implications associated with an aging America.
Demographics, Destiny, and Anticipating the Future of the Transportation System
Authors: Coughlin Joseph F. , Tompkins Curtis J.
Published: June 2009

The United States' demographic profile is changing. Tomorrow's America will be older, more ethnically and culturally diverse, experience more immigration both internally and internationally, and have a new generation of better educated women. How will these potentially disruptive demographics affect the future of the transportation system? This article outlines the objectives of a U.S. Department of Transportation, Research and Innovative Technology Administration's University Transportation Centers Program's Spotlight Conference on the Impact of Changing Demographics on the Transportation System, held at the National Academies, Washington, DC, October 2008. Seven of the several papers presented are published here as a special issue to identify key research questions and implications for both policy and practice.
Cellular Mechanism of the QT Prolongation Induced by Sulpiride
Authors: Lee Hyang-Ae , Kim Ki-Suk , Park Sang-Joon , Kim Eun-Joo
Published: June 2009

In this study, the authors investigated the electrophysiological effect of sulpiride on cardiac repolarization using conventional microelectrode recording techniques in isolated canine Purkinje fibers and a whole-cell patch clamp technique in transiently transfected cells with the hERG, KCNQ1/KCNE1, KCNJ2, and SCN5A cDNA and in rat cardiac myocytes for ICa. In studies of action potential duration, 10 μM, 100 μM, 300 μM, and 1 mM sulpiride prolonged action potential duration in a concentration-dependent manner. In studies of cardiac ion channels, sulpiride did not significantly affect INa, ICa, IKs, IK1, except for IKr. Sulpiride dose-dependently decreased the hERG tail current. It is considered that the prolonged action potential duration by sulpiride was mainly the result of inhibition of the hERG channel. The data suggest that the clinical use of sulpiride is reasonable within therapeutic plasma concentrations, but all patients taking this drug should be cautiously monitored for clinical signs of long-QT syndrome and severe arrhythmia.
Alternative Strategies for Toxicity Testing of Species-Specific Biopharmaceuticals
Authors: Bussiere Jeanine L. , Martin Pauline , Horner Michelle , Couch Jessica , Flaherty Meghan , Andrews Laura , Beyer Joseph , Horvath Christopher
Published: June 2009

Although toxicology studies should always be conducted in pharmacologically relevant species, the specificity of many biopharmaceuticals can present challenges in identification of a relevant species. In certain cases, that is, when the clinical product is active only in humans or chimpanzees, or if the clinical candidate is active in other species but immunogenicity limits the ability to conduct a thorough safety assessment, alternative approaches to evaluating the safety of a biopharmaceutical must be considered. Alternative approaches, including animal models of disease, genetically modified mice, or use of surrogate molecules, may improve the predictive value of preclinical safety assessments of species-specific biopharmaceuticals, although many caveats associated with these models must be considered. Because of the many caveats that are discussed in this article, alternative approaches should only be used to evaluate safety when the clinical candidate cannot be readily tested in at least one relevant species to identify potential hazards.
Heat Shock Protein 72 Protects Kidney Proximal Tubule Cells From Injury Induced by Triptolide by Means of Activation of the MEK/ERK Pathway
Authors: Wang Zhipeng , Jin Haifeng , Li Chen , Hou Ying , Mei Qibing , Fan Daiming
Published: June 2009

Triptolide, which has been used to treat inflammatory diseases, has also been reported to inhibit proliferation of cancer cells. However, it can cause severe nephrotoxicity, limiting its clinical use. Here, nephrotoxicity of triptolide was observed in vivo and in vitro. Heat shock protein 72 (HSP72) was upregulated during kidney injury in rats. HSP72 partially protected human kidney proximal tubule cell lines HK-2 and HKC from triptolide-induced injury. Phospho-Raf, phospho-MEK and phospho-ERK were elevated in HK-2 cells that overexpressed HSP72 after either heat shock or triptolide treatment, and downregulated when HSP72 was repressed by siRNA. The participation of the MEK/ERK1/2 pathway was confirmed by exposure of the cells to the MEK inhibitor U0126. Collectively, our results suggested that HSP72 plays a protective role by means of the MEK/ERK pathway, against triptolide-induced kidney injury.
Clinical Controversy Review: The Transformation of Vascular Surgeons to Vascular Specialists: Policy or Necessity?
Authors: Avgerinos Efthimios D. , Dalainas Ilias , Liapis Christos
Published: June 2009

The wide spreading of vascular diseases along with the emergence of minimally invasive endovascular therapies and modern medical therapies is inevitably bringing many disciplines into play. Although by definition, vascular surgery is the clinical and scientific discipline concerned with the diagnosis, treatment, and prevention of vascular diseases, many more radiologists and a significant number of cardiologists become increasingly involved. The question of which specialist among those qualified should carry out medical treatment, open, and endovascular procedures is still suspended, and a professional competition is pronounced. This article discusses the necessity of a vascular specialist who guides the holistic management of vascular diseases: open surgery, endovascular intervention, and medical therapy. The different characteristics of those intending to offer vascular care, the training curricula, the workforce demands, and the role of vascular centers are analyzed to illustrate the keystone role of vascular surgeons who are currently transforming to vascular specialists.
A Framework for Narrative-Driven Transformative Learning in Medicine
Authors: Brendel William
Published: June 2009

Like bookends, birth and death contain innumerable narratives that we come to experience, recall, and reflect on in a unique fashion throughout life. In hindsight, the bookmarks we leave behind often refer us to poignant ups and downs, many of which pertain to shifts in personal health as well as the health of those we hold dear. In this article, I will demonstrate how in medical contexts such as a terminal illness, our narratives are driven by assumptions we tend to take for granted or rarely challenge as patients. Drawing from transformative learning theory, I will suggest a framework in which medical practitioners invite narratives with the aim of helping patients identify, challenge, and in some cases transform assumptions about their health and worldviews of medicine.
Reflecting on Issues of Enacting a Critical Pedagogy in Nursing
Authors: Lynam M. Judith
Published: June 2009

This article explores the contributions critical analytic perspectives offer for understanding the conditions that contribute to inequalities in health and considers the ways these may be taken up in nursing education. This article proposes that if there is commitment in effecting transformation of, and articulating the opportunities for, action within systems of health care, to achieve more equitable health outcomes for clients, then insights generated in the critical paradigm must be translated into formative education and practice. The aim of this article is to examine and reflect on a range of critical pedagogical strategies with a view to identifying their potential for fostering uptake of insights from research generated in the critical paradigm in order to achieve transformations in practice. It is argued that insights from this work can be drawn on to inform the design of learning experiences and educational practices.
Teaching for Change in Social Work
Authors: Jones Peter
Published: June 2009

Transformative learning approaches have been applied in a diverse range of educational settings, where they have been used to develop an understanding of learners' experiences and to guide teaching and learning practices in ways that promote individual and social change. This article argues that despite clear congruence between many of the features of transformative learning theories and the nature and aims of social work education, this theoretical perspective has yet to be incorporated into thinking around critical approaches to the education of future social work practitioners. Drawing on literature that highlights the centrality of experience, critical reflection, and dialogue to the learning process, and that demonstrates a commitment in both social work and the broader field of transformative education to promoting individual and social change, the benefits of using a transformative learning approach in social work education are discussed. These benefits may be of particular significance for social work educators seeking to promote emancipatory perspectives in their profession.
Geographical and Psychological Terrains of Adults From War-Affected Backgrounds
Authors: Magro Karen , Polyzoi Eleoussa
Published: June 2009

This qualitative study uses transformative learning theory as a lens to interpret and understand the challenges and barriers that Canadian and Greek adult refugees experience. In essence, transformative learning is a deeper level learning that challenges learners to understand themselves and their world in a new way. Aspects of the refugee experience common to both Canadian and Greek individuals include being forced to flee zones of conflict and war; the experience of trauma, separation, and loss; the challenge of rebuilding one's life in an unfamiliar culture; and the process of learning to navigate new cultural, linguistic, and social mores. Situational and institutional barriers make the task of resettlement more complex.
The Use of Holmium Laser Technology for the Treatment of Refractory Common Bile Duct Stones, With a Short Review of the Relevant Literature
Authors: Day Andrew , Sayegh Mazin E. , Kastner Christof , Liston Tom
Published: June 2009

Background. The treatment of common bile duct (CBD) stones can vary in complexity and many methods exist to fragment them before removal. Although holmium laser is frequently used in urological surgery, it is rarely used to achieve this aim. Methods. The holmium laser was passed along a fiber introduced via a flexible scope through the cystic duct at the time of laparoscopic cholecystectomy. This energy modality was used to fragment the stones to a size that allowed easy removal. Results. The authors have used this technique once so far and achieved complete clearance of the CBD with no mucosal damage. Conclusion. Holmium laser provides an alternative and realistic treatment option for difficult CBD stones.
Anal Incontinence Improvement After Silicone Injection May Be Related to Restoration of Sphincter Asymmetry
Authors: Oliveira Lucia C. C. , Neves Jorge José Marcio , Yussuf Sonia , Habr-Gama Angelita , Kiss Desidério , Cecconello Ivan
Published: June 2009

Background. This study aimed to evaluate manometric parameters that may explain improvement in anal incontinence using a silicone bulking agent. Methods. Incontinent patients having internal sphincter defects were prospectively selected and injected with a silicone bulking agent. Manometry and endoanal ultrasound were performed before and 3 months after injections. Twenty continent healthy volunteers were used only for manometric comparison. Results. Thirty-five patients (28 females; mean age 60.3 years) and 20 controls entered this study. Patients had lower resting and squeeze pressures compared with controls ( P < .05). Length of the high-pressure zone increased from 1 to 1.7 cm postinjection ( P = .002). Asymmetry index showed a significant change postinjection ( P < .001). Conclusion. Despite considerable clinical improvement, no significant increase in manometric pressures was noted posttreatment. There was significant improvement in both high-pressure zone and asymmetry index, and these findings may explain the mechanism of action of the bulking agent injected.
Training and Working in High-Stakes Environments: Lessons Learned and Problems Shared by Aviators and Surgeons
Authors: Schwaitzberg Steven D. , Godinez Charles , Kavic Stephen M. , Sutton Erica , Worthington Raymond B. , Colburn Brian , Park Adrian
Published: June 2009

Surgeons and naval aviators are both trained to work in high-stakes environments. Any misadventure in either of their working worlds can lead to death. Yet the pathways to certification and implicit attitudes toward training are quite different in these 2 disciplines and provide an opportunity to compare and contrast the methodologies employed. At the 5th annual Innovations in the Surgical Environments Conference, senior and junior aviators and surgeons shared their experiences from the perspective of trainee and trainer and in the process presented an interesting study in parallels and contrasts. The US Navy follows a highly regimented training syllabus with graduated levels of responsibility designed to create the safest possible flying environment. Extensive preflight and postflight effort is required for each mission flown. Surgical training is also hierarchal in responsibility, but graduates demonstrate greater variability in their training experience. The surgical field can only fortify its emphasis on safety by seeking to provide the optimal training experiences necessary in the high-stakes environment of the operating theater. In doing so, surgeons may find reinvigorated commitment through study of the aviation industry's established methods of training and practice.
Blackwell Optimality for Controlled Diffusion Processes
Authors: Jasso-Fuentes Héctor , Hernández-Lerma Onésimo
Published: June 2009

In this paper we study m-discount optimality (m ≥ −1) and Blackwell optimality for a general class of controlled (Markov) diffusion processes. To this end, a key step is to express the expected discounted reward function as a Laurent series, and then search certain control policies that lexicographically maximize the mth coefficient of this series for m = −1,0,1,…. This approach naturally leads to m-discount optimality and it gives Blackwell optimality in the limit as m → ∞.
Maximizing the Expected Duration of Owning a Relatively Best Object in a Poisson Process with Rankable Observations
Authors: Kurushima Aiko , Ano Katsunori
Published: June 2009

Suppose that an unknown number of objects arrive sequentially according to a Poisson process with random intensity λ on some fixed time interval [0,T]. We assume a gamma prior density Gλ(r, 1/a) for λ. Furthermore, we suppose that all arriving objects can be ranked uniquely among all preceding arrivals. Exactly one object can be selected. Our aim is to find a stopping time (selection time) which maximizes the time during which the selected object will stay relatively best. Our main result is the following. It is optimal to select the ith object that is relatively best and arrives at some time si(r) onwards. The value of si(r) can be obtained for each r and i as the unique root of a deterministic equation.
Double Optimal Stopping in the Fishing Problem
Authors: Karpowicz Anna
Published: June 2009

In this paper we consider the following problem. An angler buys a fishing ticket that allows him/her to fish for a fixed time. There are two locations to fish at the lake. The fish are caught according to a renewal process, which is different for each fishing location. The angler's success is defined as the difference between the utility function, which is dependent on the size of the fish caught, and the time-dependent cost function. These functions are different for each fishing location. The goal of the angler is to find two optimal stopping times that maximize his/her success: when to change fishing location and when to stop fishing. Dynamic programming methods are used to find these two optimal stopping times and to specify the expected success of the angler at these times.
A Two-Step Branching Splitting Model Under Cost Constraint for Rare Event Analysis
Authors: Lagnoux-Renaudie Agnès
Published: June 2009

In this paper we consider the splitting method first introduced in rare event analysis. In this technique, the sample paths are split into R multiple copies at various stages to speed up the simulation. Given the cost, the optimization of the algorithm suggests taking all the transition probabilities to be equal; nevertheless, in practice, these quantities are unknown. We address this problem by presenting an algorithm in two phases.
Similar States in Continuous-Time Markov Chains
Authors: Yap V. B.
Published: June 2009

In a homogeneous continuous-time Markov chain on a finite state space, two states that jump to every other state with the same rate are called similar. By partitioning states into similarity classes, the algebraic derivation of the transition matrix can be simplified, using hidden holding times and lumped Markov chains. When the rate matrix is reversible, the transition matrix is explicitly related in an intuitive way to that of the lumped chain. The theory provides a unified derivation for a whole range of useful DNA base substitution models, and a number of amino acid substitution models.
On the Maximum Exceedance of a Sequence of Random Variables Over a Renewal Threshold
Authors: Ha Xuemiao , Tang Qihe , Wei Li
Published: June 2009

In this paper we study the tail behavior of the maximum exceedance of a sequence of independent and identically distributed random variables over a random walk. For both light-tailed and heavy-tailed cases, we derive a precise asymptotic formula, which extends and unifies some existing results in the recent literature of applied probability.
Poisson Approximation in a Poisson Limit Theorem Inspired by Coupon Collecting
Authors: Pósfai Anna
Published: June 2009

In this paper we refine a Poisson limit theorem of Gnedenko and Kolmogorov (1954): we determine the error order of a Poisson approximation for sums of asymptotically negligible integer-valued random variables that converge in distribution to the Poisson law. As an application of our results, we investigate the case of the coupon collector's problem when the distribution of the collector's waiting time is asymptotically Poisson.
A Stochastic Model for Phylogenetic Trees
Authors: Liggett Thomas M. , Schinazi Rinaldo B.
Published: June 2009

We propose the following simple stochastic model for phylogenetic trees. New types are born and die according to a birth and death chain. At each birth we associate a fitness to the new type sampled from a fixed distribution. At each death the type with the smallest fitness is killed. We show that if the birth (i.e. mutation) rate is subcritical, we obtain a phylogenetic tree consistent with an influenza tree (few types at any given time and one dominating type lasting a long time). When the birth rate is supercritical, we obtain a phylogenetic tree consistent with an HIV tree (many types at any given time, none lasting very long).
High-sensitivity HPLC Quantification of Nonfluorescent but Photolabile Analyte through Photoreversion in Fluorescence Detector
Authors: Nishijima Masaki , Wada Takehiko , Nagamori Koushi , Inoue Yoshihisa
Published: June 2009

Ultrahigh sensitivity chiral HPLC analysis of nonfluorescent cyclodimers of 2-anthracenecarboxylic acid (AC) was achieved with much improved accuracy and reproducibility through a nonconventional on-detector photoreversion/re-excitation/detection mechanism. Excitation of cyclodimers at 254 nm in the detector cuvette caused photoreversion to AC, in situ excitation of which led to strong fluorescence at longer λ. The sensitivity was enhanced by a factor of ca. 2000 compared to usual UV detection.
Hydrolysis of Disaccharides by Metal Species in Neutral Homogeneous Solutions
Authors: Takahashi Daisuke , Kobayashi Sakiko , Tsumura Kana , Toshima Kazunobu
Published: June 2009

Metal species, including lanthanoid(III) ions were found to effectively hydrolyze disaccharides to the corresponding monosaccharides at 80 °C without the accompanying oxidative cleavage under neutral conditions.
Switchable transmissive and reflective liquid‐crystal display using a multi‐domain vertical alignment
Authors: Ge Zhibing , Zhu Xinyu , Wu Thomas X. , Wu Shin‐Tson , Li Wang‐Yang , Wei Chung‐Kuang
Published: June 2009

Abstract— A wide‐view transflective liquid‐crystal display (LCD) capable of switching between transmissive and reflective modes in response to different ambient‐light conditions is proposed. This transflective LCD adopts a single‐cell‐gap multi‐domain vertical‐alignment (MVA) cell that exhibits high contrast ratio, wide‐viewing angle, and good light transmittance (T) and reflectance (R). Under proper cell optimization, a good match between the VT and VR curves can also be obtained for single‐gamma‐curve driving.
Moving‐picture response time (MPRT) of LCDs for the oblique viewing direction
Authors: Hong HyungKi , Yoon JaeKyeong , Lim Moojong
Published: June 2009

Abstract— The dynamic performance of displays is an important characteristic for multimedia applications. Motion‐picture response time (MPRT) has been used as an indicator of the dynamic performance of LCDs. This paper describes a comprehensive method of MPRT evaluation for the oblique viewing direction. By using a tilted camera configuration, the angular dependency of MPRT is investigated for the condition that the horizontally scrolling patterns are observed from the vertical direction. For each gray‐to‐gray transition, distinct changes in MPRT and the luminance profile of blur are observed.
Image improvement in a laser projection display with a spatial light modulator with a deformable polymer
Authors: Kartashov Vladimir , Henriksen Lars , Ulvensøen Jon Herman , Svardal Benny , Svortdal Tore , Berglind Richard , Hedin Gunnar
Published: June 2009

Abstract— The image quality of a laser projection display based on a spatial light modulator with a deformable polymer layer (SLMDPL) has been improved. Bias diffraction has been reduced by two methods: (1) by filling the spacings between electrodes with SiO2 followed by deposition of a slightly conductive thin film and (2) by splitting electrodes. Both methods resulted in a contrast ratio of ≃1200:1, which is significantly better than 50:1 measured for an earlier type of SLMDPL. Different methods of reducing the influence of electrical‐charge movement on the image quality have also been investigated. Substantial improvement has been achieved by using an alternating mode for signal voltage pulses, by increasing the conductivity of the gel layer, and by increasing the surface conductivity of the substrate between electrodes. Cross‐talk between neighboring pixels has been suppressed without a loss in the sensitivity by using a special layout of the electrodes in the SLMDPL.
Laser display with single‐mirror MEMS scanner
Authors: Schreiber Peter , Hoefer Bernd , Braeuer Andreas , Scholles Michael
Published: June 2009

Abstract— While arrayed DMD and LCD microdisplays are well‐established approaches for visualization tasks, image‐forming laser scanners are an emerging technology used to build miniaturized projection displays. A directly modulated RGB‐laser module consisting of diode lasers for red and blue and a frequency‐doubled semiconductor laser for green with color combining optics form the light source for the laser scanner have been developed. Subsequent beam‐shaping optics suppresses unwanted stray light and enables optimum illumination of the scanning mirror. The MEMS device features a single scanning mirror oscillating in two directions in resonant mode. This requires appropriate data delivery realized by a custom‐made driving logic, which converts the pixel stream originally arranged in rows and columns to the Lissajous‐like spot trajectory on the screen. Additionally, the increased image brightness at the vertical and horizontal borders of the field of view (FOV) is also compensated by the modulation of laser power. Theoretical investigations of the resulting maximum achievable system transmission are presented. Different systems, such as an extremely miniaturized monochrome projection head with an integrated diode laser and a full‐color projector have been realized. Important problems to be tackled are fast analog modulation of the laser power with high resolution and improved suppression of stray light and speckle.
Microdisplay‐based industrial 3‐D and microstructure measurement systems
Authors: Riehemann Stefan , Lippmann Uwe , Palme Martin , Großmann Constanze , Kuehmstedt Peter , Notni Gunther
Published: June 2009

Abstract— Microdisplays, whether they are of the liquid‐crystal‐on‐silicon (LCOS) or organic light‐emitting diode (OLED) type, have been, up until now, mainly used in multimedia applications or head‐mounted displays. Due to their interesting possibilities, these displays open more and more alternative applications; for example, in optical metrology. Projection lenses for this application area need to be specially designed because the requirements on these systems differ completely from those for multimedia applications. The lenses must have very low geometrical image distortion and they have to be adapted to small objects and/or image distances. On the other hand, they often work with light sources with small spectral bandwidths; consequently, they do not need to be corrected for chromatic aberrations. In addition, the numerical aperture has to be large enough to collect and transfer as much light as possible, but also the size of the projection lens has to be as small as possible to ensure compact measurement systems. All these requirements lead to a compromise in optical lens design. Three optical system designs and realizations — one with an OLED microdisplay and two with an LCOS microdisplay — are presented.
Design of a compact projection display for the visualization of 3‐D images using polarization sensitive eyeglasses
Authors: Bogaert Lawrence , Meuret Youri , van Giel Bart , de Smet Herbert , Thienport Hugo
Published: June 2009

Abstract— A compact optical architecture of a three‐dimensional projection display that simultaneously generates two full‐color images with an orthogonal polarization state is presented. The minimal size of the optical engine was investigated and a compact illumination system using light‐emitting diodes as light sources was designed. The effect of dichroic mirrors in the illumination path on the stereoscopic images was also investigted.