bluuebunny/crossref_metadata_2025 huggingface dataset:
Zur Beteiligung potentieller Blut-Ersatzlösungen mit Sauerstoffträgereigenschaften und deren Einsatzmöglichkeiten
Authors: Zander R.
Published: May 2009

Neben dem notwendigen Volumeneffekt (isoosmotische und isoonkotische Lösung) und der physiologischen Bicarbonatkonzentration (Verhinderung der Dilutions-Azidose) sollte eine potentielle Blut-Ersatzlösung mit O2-Trägereigenschaften einen optimalen O2-Transport ermöglichen: Viskosität so niedrig wie möglich und unabhängig vom Schergrad (Newton’sches Verhalten), O2-Konzentration beim gegebenen O2-Partialdruck mindestens 6 ml/dl und mittlerer kapillärer O2-Partialdruck so hoch wie möglich. Zur Beurteilung eines derartigen Blut-Ersatzes wird der sogenannte O2-Versorgungsindex vorgeschlagen, das Produkt aus O2-Konzentration und mittlerem kapillärem O2-Partialdruck dividiert durch die Viskosität.
L-Type Calcium Channel C Terminus Autoregulates Transcription
Authors: Schroder Elizabeth , Byse Miranda , Satin Jonathan
Published: May 2009

Calcium homeostasis is critical for cardiac myocyte function and must be tightly regulated. The guiding hypothesis of this study is that a carboxyl-terminal cleavage product of the cardiac L-type calcium channel (Ca
V
1.2) autoregulates expression. First, we confirmed that the Ca
V
1.2 C terminus (CCt) is cleaved in murine cardiac myocytes from mature and developing ventricle. Overexpression of full-length CCt caused a 34±8% decrease of Ca
V
1.2 promoter activity, and truncated CCt caused an 80±3% decrease of Ca
V
1.2 promoter (n=12). The full-length CCt distributes into cytosol and nucleus. A deletion mutant of CCt has a greater relative affinity for the nucleus than full-length CCt, and this is consistent with increased repression of Ca
V
1.2 promoter activity by truncated CCt. Chromatin immunoprecipitation analysis revealed that CCt interacts with the Ca
V
1.2 promoter in adult ventricular cardiac myocytes at promoter modules containing Nkx2.5/Mef2, C/EBp, and a
cis
regulatory module. The next hypothesis tested was that CCt contributes to transcriptional signaling associated with cellular hypertrophy. We explored whether fetal cardiac myocyte Ca
V
1.2 was regulated by serum in vitro. We tested atrial natriuretic factor promoter activity as a positive control and measured the serum response of Ca
V
1.2 promoter, protein, and L-type current (
I
Ca,L
) from fetal mouse ventricular myocytes. Serum increased atrial natriuretic factor promoter activity and cell size as expected. Serum withdrawal increased Ca
V
1.2 promoter activity, mRNA, and
I
Ca,L
. Moreover, serum withdrawal decreased the relative nuclear localization of CCt. A combination of promoter deletion mutant analyses, and the response of promoter mutants to serum withdrawal support the conclusion that CCt, a proteolytic fragment of Ca
V
1.2, autoregulates Ca
V
1.2 expression in cardiac myocytes. These data support the novel mechanism that a mobile segment of Ca
V
1.2 links Ca handling to nuclear signaling.
Lipoprotein Accumulation in Macrophages via Toll-Like Receptor-4–Dependent Fluid Phase Uptake
Authors: Choi Soo-Ho , Harkewicz Richard , Lee Jee Hyun , Boullier Agnès , Almazan Felicidad , Li Andrew C. , Witztum Joseph L. , Bae Yun Soo , Miller Yury I.
Published: May 2009

Toll-like receptor (TLR)4 recognizes microbial pathogens, such as lipopolysaccharide, and mediates lipopolysaccharide-induced proinflammatory cytokine secretion, as well as microbial uptake by macrophages. In addition to exogenous pathogens, TLR4 recognizes modified self, such as minimally oxidized low-density lipoprotein (mmLDL). Here we report that mmLDL and its active components, cholesteryl ester hydroperoxides, induce TLR4-dependent fluid phase uptake typical of macropinocytosis. We show that mmLDL induced recruitment of spleen tyrosine kinase (Syk) to a TLR4 signaling complex, TLR4 phosphorylation, activation of a Vav1-Ras-Raf-MEK-ERK1/2 signaling cascade, phosphorylation of paxillin, and activation of Rac, Cdc42, and Rho. These mmLDL-induced and TLR4- and Syk-dependent signaling events and cytoskeletal rearrangements lead to enhanced uptake of small molecules, dextran, and, most importantly, both native and oxidized LDL, resulting in intracellular lipid accumulation. An intravenous injection of fluorescently labeled mmLDL in wild-type mice resulted in its rapid accumulation in circulating monocytes, which was significantly attenuated in TLR4-deficient mice. These data describe a novel mechanism leading to enhanced lipoprotein uptake in macrophages that would contribute to foam cell formation and atherosclerosis. These data also suggest that cholesteryl ester hydroperoxides are an endogenous ligand for TLR4. Because TLR4 is highly expressed on the surface of circulating monocytes in patients with chronic inflammatory conditions, and cholesteryl ester hydroperoxides are present in plasma, lipid uptake by monocytes in circulation may contribute to the pathological roles of monocytes in chronic inflammatory diseases.
The Performance of MRI-Based Cerebral Blood Flow Measurements in Acute and Subacute Stroke Compared With 15O-Water Positron Emission Tomography
Authors: Zaro-Weber Olivier , Moeller-Hartmann Walter , Heiss Wolf-Dieter , Sobesky Jan
Published: May 2009

Background and Purpose—

Perfusion-weighted MRI-based maps of cerebral blood flow (CBF
MRI
) are considered a good MRI measure of penumbral flow in acute ischemic stroke but are seldom used in clinical routine due to methodical issues. We validated CBF
MRI
on quantitative CBF measurement by 15O-water positron emission tomography (CBF
PET
).

Material and Methods—

Comparative CBF
MRI
and CBF
PET
were performed in patients with acute and subacute stroke. In a voxel-based seed-growing technique, predefined CBF
MRI
thresholds (<40, <30, <20, <10 mL/100 g/min) were applied and the resulting volumes were compared with the hypoperfusion volume detected by the penumbral threshold (<20 mL/100 g/min) on CBF
PET
. The volumetric comparison was expressed as the C-ratio (volume CBF
MRI
/volume CBF
PET
) to identify the best MRI threshold. The influence of vessel pathology, hypoperfusion size, and time point of imaging was described. The proportion of voxels correctly classified as hypoperfused and the proportion of voxel correctly classified as nonhypoperfused of the best CBF
MRI
threshold was calculated and a Bland-Altman plot illustrated the method-specific differences.

Results—

In 24 patients (median time MRI to PET: 68 minutes; 16 patients imaged within 24 hours after stroke), the median volume of hypoperfusion <20 mL/100 g/min (CBF
PET
) was 78.5 cm
3
. Median hypoperfusion volume on CBF
MRI
ranged from 245.9 cm
3
(<40 mL/100 g/min) to 35.5 cm
3
(<10 mL/10 g/min). On visual inspection, an excellent qualitative congruence was found. The quantitative congruence was best for the MRI-CBF threshold <20 mL/100 g/min (median C-ratio: 1.0), reaching a proportion of voxels correctly classified as hypoperfused of 76% and a proportion of voxel correctly classified as nonhypoperfused of 96%, but a wide interindividual range (C-ratio 0.3 to 3.5) was found. Ipsilateral vessel pathology, time point of imaging, and size of hypoperfusion did not significantly influence the C-ratio. The Bland-Altman analysis for the volumetric difference of CBF
MRI
and CBF
PET
found a good overall agreement but a large SD.

Conclusion—

Hypoperfusion areas below the CBF
PET
penumbral threshold can be well identified by the CBF
MRI
threshold <20 mL/10 g/min at a group level, but a large individual variance (exceeding 20% of volume in nearly half of the patients) could not be explained. Our results support a prudent use of MRI-based quantitative CBF measurement in clinical routine.
Influence of Weekend Hospital Admission on Short-Term Mortality After Intracerebral Hemorrhage
Authors: Crowley R. Webster , Yeoh Hian K. , Stukenborg George J. , Medel Ricky , Kassell Neal F. , Dumont Aaron S.
Published: May 2009

Background and Purpose—

There is expanding literature to show that certain patients admitted during the weekend have worse outcomes than similar patients admitted during the week. Although many clinicians have hypothesized the presence of this “weekend effect” with patients with intracerebral hemorrhage, there is a paucity of studies validating this conjecture.

Methods—

We performed a retrospective cohort study of patients with intracerebral hemorrhage (International Classification of Diseases, 9th Revision, Clinical Modification=431) extracted from the 2004 Nationwide Inpatient Sample. Multivariable logistic regression analyses and Cox proportional hazards regression were conducted to calculate the odds of death (within 7, 14, and 30 days) and the hazard ratio of death for patients with weekend intracerebral hemorrhage admissions compared with weekday intracerebral hemorrhage admissions. All analyses were adjusted for concurrent differences in length of stay, patient demographics, and comorbid disease.

Results—

Weekend hospital admissions accounted for 26.8% of the 13 821 patients with a diagnosis of intracerebral hemorrhage in the National Inpatient Sample. Admission during the weekend was a statistically significant independent predictor of death within 7 days (OR, 1.14; 95% CI, 1.05 to 1.25), within 14 days (OR, 1.15; 95% CI, 1.05 to 1.25), and within 30 days (OR, 1.15; 95% CI, 1.05 to 1.25). The adjusted hazard of in-hospital death (hazard ratio, 1.12; CI, 1.05 to 1.20) indicates that the overall risk of in-hospital death with intracerebral hemorrhage is 12% higher with weekend admission.

Conclusion—

Weekend admission for intracerebral hemorrhage was associated with increased risk-adjusted mortality when compared with admission during the remainder of the week.
Performance of Bedside Transpulmonary Thermodilution Monitoring for Goal-Directed Hemodynamic Management After Subarachnoid Hemorrhage
Authors: Mutoh Tatsushi , Kazumata Ken , Ishikawa Tatsuya , Terasaka Shunsuke
Published: May 2009

Background and Purpose—

Early goal-directed hemodynamic therapy is of particular importance for adequate cerebral circulation of patients with vasospasm after subarachnoid hemorrhage but is often precluded by the invasiveness of established cardiac output determination using a pulmonary artery catheter. This study was undertaken to validate the usefulness of less invasive goal-directed hemodynamic monitoring by transpulmonary thermodilution technique in patients after subarachnoid hemorrhage.

Methods—

One hundred sixteen patients with subarachnoid hemorrhage who underwent surgical clipping within 24 hours of ictus were investigated. Validation of transpulmonary thermodilution-derived intermittent/continuous cardiac output and cardiac preload (global end diastolic volume) were compared with pulmonary artery catheter-derived reference cardiac output and pulmonary capillary wedge pressure or central venous pressure in 16 patients diagnosed with vasospasm. In a subsequent trial of 100 consecutive cases, clinical results between the new and standard management paradigms were compared.

Results—

Transpulmonary thermodilution-derived intermittent cardiac output and transpulmonary thermodilution-derived continuous cardiac output showed close agreement to catheter-derived reference cardiac output with high correlation (
r
=0.85 and 0.77) and low percentage error (13.5% and 18.0%). Fluid responsiveness to defined volume loading was predicted better with global end diastolic volume than with pulmonary capillary wedge pressure and central venous pressure for larger receiver operating characteristic curve area. Patients receiving early goal-directed management by transpulmonary thermodilution experienced reduced frequencies of vasospasm and cardiopulmonary complications compared with those managed with standard therapy (
P
<0.05), whereas their functional outcomes at 3 months were not different (
P
=0.06).

Conclusions—

Goal-directed hemodynamic management guided by transpulmonary thermodilution appears to have a therapeutic advantage for optimizing the prognosis of patients with subarachnoid hemorrhage with vasospasm over conventional methods.
Gender Differences in Acute Ischemic Stroke
Authors: Förster Alex , Gass Achim , Kern Rolf , Wolf Marc E. , Ottomeyer Caroline , Zohsel Katrin , Hennerici Michael , Szabo Kristina
Published: May 2009

Background and Purpose—

Differences between women and men in relation to stroke are increasingly being recognized.

Methods—

From July 2004 until June 2007, 237 acute ischemic stroke (AIS) patients were treated with recombinant tissue plasminogen activator (rtPA) within 3 hours after onset of symptoms in our stroke unit. Baseline characteristics, etiology, CT/MRI stroke patterns, clinical outcome, and complications of women were compared to those of men.

Results—

Of 237 AIS patients (mean age 70.7 years), 111 (46.8%) were women and 126 (53.2%) were men. Women were older (
P
=0.001), but history of hyperlipidemia (
P
=0.03), smoking (
P
=0.03), and coronary heart disease (
P
<0.001) was less frequent than in men. Internal carotid artery disease occurred more often in men (
P
=0.02), whereas atrial fibrillation was observed more often in women (
P
=0.002). In men borderzone/small embolic and lacunar stroke was found more frequently (39.7 versus 27.2%), whereas women showed a higher percentage of large territorial stroke (72.8 versus 60.3%,
P
=0.09). Baseline National Institute of Health Stroke Scale scores (12.5 versus 11.3), NIHSS score at discharge (11.0 versus 9.5), 3-month-outcome modified Rankin Scale score, thrombolysis-related (17.1% versus 13.5%) or independent complications (32.4% versus 30.2%), and mortality after 3 months (13.5% versus 9.5%) were similar.

Conclusion—

Differences of stroke lesion patterns in genders are paralleled by differences in etiology and risk factor profiles (women, cardioembolism; men, large and small vessel disease). Baseline characteristics, rates of rtPA-related and independent complications, as well as clinical outcomes were not different between women and men with AIS.
Imitation as a Mechanism of Cultural Transmission
Authors: Marriott Chris , Parker James , Denzinger Jörg
Published: May 2009

We study the effects of an imitation mechanism on a population of animats capable of individual ontogenetic learning. An urge to imitate others augments a network-based reinforcement learning strategy used in the control system of the animats. We test populations of animats with imitation against populations without for their ability to find, and maintain over generations, successful foraging behavior in an environment containing three necessary resources: food, water, and shelter. We conclude that even simple imitation mechanisms are effective at increasing the frequency of success when measured over time and over populations of animats.
Forward with Fairness? Industrial Relations under Labor in 2008
Authors: Cooper Rae
Published: May 2009

The Rudd government was elected in late 2007 after a national election campaign centred squarely on industrial relations. In 2008, with a massive mandate, the government presented key pieces of legislation to the Australian parliament, aimed at moving away from the Howard government's Work Choices and toward implementing the `Forward with Fairness' election policy. The government's substantive industrial relations legislation — the Fair Work Bill — was introduced late in 2008 to widespread, though not universal, approval from trade unionists and, at first, muted acceptance and, later, and in the face of deteriorating economic circumstances, sharper criticism from employer groups.
Employer Matters in 2008
Authors: Mackinnon Bruce Hearn
Published: May 2009

In terms of employer matters, the year 2008 may be best characterized as one dominated by change, challenge and Canberra, as the political landscape was transformed, industrial relations legislation was rewritten and global capitalism went into financial meltdown. The new political and economic environment seemed to demand a greater emphasis on consultation, efforts at cooperation and, dare I say it, in some cases even `consensus'. Nevertheless, employers were nonetheless active in pursuing their own objectives, with the main employer associations preoccupied for most of 2008 lobbying for changes and amendments to the form and substance of Labor's new industrial relations regime, Forward with Fairness. Importantly, the new industrial and legal landscape suggested that the changed status of the `parties' vis-a-vis awards, is likely to lead to increased competition for relevance among employer associations, leading to a series of amalgamations and rationalization, much as occurred with unions in the 1990s.
Rethinking the Regulation of Vulnerable Work in the USA: A Sector-based Approach
Authors: Weil David
Published: May 2009

This article discusses one of the major challenges of US workplace policy: protecting roughly 35m workers who are vulnerable to a variety of major risks in the workplace. After laying out the dimensions of this problem, I show that the vulnerable workforce is concentrated in a subset of sectors with distinctive industry characteristics. Examining how employer organizations relate to one another in these sectors provides insight into some of the causes as well as possible solutions for redressing workforce vulnerability in the US as well as other countries facing similar problems.
The Impact of the Financial and Economic Crisis on European Tourism
Authors: Smeral Egon
Published: May 2009

This study1 concentrates on analysing and forecasting demand for international travel of the EU 15 countries in terms of tourism imports at constant prices and exchange rates. Starting out from a description of the key macroeconomic factors, it then analyses their effect on tourism demand and develops forecast models. Two scenarios are evolved to project demand for foreign travel in 2009 and 2010, and their findings are discussed. Subsequently, proposals are developed for strategies aimed to mitigate the consequences of the crisis.
Micronutrient Supplementation in Adult Nutrition Therapy: Practical Considerations
Authors: Sriram Krishnan , Lonchyna Vassyl A.
Published: May 2009

Preexisting micronutrient (vitamins and trace elements) deficiencies are often present in hospitalized patients. Deficiencies occur due to inadequate or inappropriate administration, increased or altered requirements, and increased losses, affecting various biochemical processes and resulting in organ dysfunction, poor wound healing, and altered immune status with deleterious sequelae. Guidelines for the 13 essential vitamins and 10 essential trace elements have been established. These recommendations, however, are applicable to healthy adults and not to critically ill patients, in whom decreased serum levels may indicate actual deficiencies or a deficiency due to redistribution. Benefits of supplementation over and above the daily requirements, which may not result in increased serum levels, are also unclear and may, in fact, be detrimental. Vitamin requirements are increased in disease states, but a similar recommendation for trace elements has not been initiated except for selenium (Se) and zinc (Zn). In practice, a multivitamin preparation and a multiple trace element admixture (containing Zn, Se, copper, chromium, and manganese) are added to parenteral nutrition formulations. Most enteral nutrition preparations also contain adequate amounts of vitamins and trace elements, although bioavailability may be an issue. Detailed information about individual micronutrient use specifically in hospitalized adult patients receiving nutrition therapy will be discussed, emphasizing the practical and clinical aspects. Clinicians are encouraged to think of micronutrients not as nutritional supplements alone but also as therapeutic agents and nutraceuticals.
The π-index: a new indicator for assessing scientific impact
Authors: Vinkler Peter
Published: May 2009

There are several simple and sophisticated scientometric indicators generally applied in the literature (e.g. total number of publications and citations, citations per journal paper, relative citedness indexes, Hirsch index, etc.), which may characterize the publications of scientists both qualitatively and quantitatively. The calculation methods generally use data referring to the total set of papers studied. Scientific progress, however, may be attributed primarily to information in the highly cited publications. Therefore, a new indicator (π-index) is suggested for comparative assessment of scientists active in similar subject fields. The π-index is equal to one hundredth of the number of citations obtained to the top square root of the total number of journal papers (‘elite set of papers’) ranked by the decreasing number of citations. The relation of the π-index to other indexes and its dependence on the field is studied, using data of journal papers of ‘highly cited researchers’.
Power and Organizational Transformation through Technology: Hybrids of Electronic Government
Authors: Bloomfield Brian P. , Hayes Niall
Published: May 2009

This paper considers the UK Government's major modernization programme for local government and its aim to use technology to bring about a radical transformation in the delivery of public services by joining up hitherto separate service departments and focusing the organization of services around the citizen. Drawing upon empirical fieldwork in the North of England, the paper seeks to shed light on the realization and operation of modernization and considers the issues of power and hybridity involved in the emplacement of new organizational configurations (`front office' contact centres and `back office' service departments) to handle citizen inquiries.
States, Power, Legitimacy, and Maintaining Institutional Control: The Battle for Private Sector Telecommunication Services in Zimbabwe
Authors: Goodstein Jerry D. , Velamuri S. Ramakrishna
Published: May 2009

Drawing directly on Stinchcombe (1968, 1983) we study the interdependence between power and legitimacy in state—organization contests for maintaining institutional control. We focus on postcolonial sub-Saharan Africa and the dynamics between the Zimbabwean state and Econet Wireless Zimbabwe, a start-up private firm that challenged the state's rights to monopoly control over the telecommunications sector during the period 1993—1998. Our findings show that in contexts such as postcolonial settings, states use their power to dominate institutional sectors and maintain institutional control. We find as well that states can attempt to reinforce the legitimacy of their use of power and coercion through (1) securing critical property rights and embedding these rights in the state bureaucracy, and (2) calling on other `centers of power'. Finally, our study highlights the ways in which states and challenging organizations engage in various strategies of institutional work to maintain and disrupt, respectively, existing structures and practices of institutional control.
Market Shaping as an Answer to Ambiguities: The Case of Credit Derivatives
Authors: Huault Isabelle , Rainelli-Le Montagner Hélène
Published: May 2009

Building on Smith (1989), we describe the social processes surrounding a new financial OTC derivatives market,3 the market for credit derivatives. We show that in contradiction to more traditional derivatives, credit derivatives generate ambiguities of a cognitive and political nature. By conducting an in-depth longitudinal qualitative study from 1996 to 2004, we document the efforts made by the promoters of the market to alleviate these ambiguities and show how the size of resources needed results in the leadership of the most powerful. We thus provide a socially based explanation for the concentration and lack of transparency of the market. Our research exemplifies the contradictions between the rhetorical justification of financial innovations provided by financial theory and the empirical realities of a modern derivative market. It suggests that the actual structure of the market might best be understood by paying attention to the way different cognitive and political communities react to these contradictions.
Internationalization and Alliance Formation
Authors: Ali Ulubaşoğlu Mehmet , Akdiş Muhammet , Kök Sabahat Bayrak
Published: May 2009

This study explores the issue of internationalization through forming alliances with foreign capital in the small business sector in Turkey. Using a sample of 257 SMEs from this emerging market economy, collected via a field study, it finds that Turkish SMEs would like to form alliances with foreign capital for expanding their production capacity and accessing to world markets. Multivariate multinomial logit models are employed to analyse the survey data econometrically. Size-specific, sector-specific and management-specific factors are identified in the alliance motivation. The `market' and `finance' aspects of alliances prevail in the multivariate analysis with significant implications. There is also evidence that some conditional relationships offered by multivariate analysis differ from unconditional associations found in the survey, which implies that alliance motivation is partly a product of multidimensional decision-making process on behalf of SMEs.
An Anatomy of Media Hypes
Authors: Wien Charlotte , Elmelund-Præstekær Christian
Published: May 2009

■Media hypes are a well known phenomenon. They occur on a regular basis and attract much media attention, but there is very little knowledge about them. This article supplements Vasterman's analysis of the phenomenon and presents new empirical evidence. Through a case study of five Danish media hypes occurring between 2000 and 2005, the article shows that not every event has the potential to trigger a media hype: it must, of course, satisfy the general news values, but should also contain some violation of norms, be suitable for public debate and, finally, it must be possible for the media to cover the event from a variety of perspectives. Concerning the structure and dynamics of the media hype, the article concludes that media hypes begin with a trigger event, they last approximately three weeks and come in several, usually three, waves of decreasing intensity. ■
Neural activity changes to emotional stimuli in healthy individuals under chronic use of clomipramine
Authors: Cardoso de Almeida JR , Phillips ML , Cerqueira CT , Zilberman M. , Lobo D. , Henna E. , Tavares H. , Amaro E. , Gorenstein C. , Gentil V. , Busatto GF
Published: May 2009

Previous functional magnetic resonance imaging (fMRI) studies examined neural activity responses to emotive stimuli in healthy individuals after acute/subacute administration of antidepressants. We now report the effects of repeated use of the antidepressant clomipramine on fMRI data acquired during presentation of emotion-provoking and neutral stimuli on healthy volunteers. A total of 12 volunteers were evaluated with fMRI after receiving low doses of clomipramine for 4 weeks and again after 4 weeks of washout. Fear-, happiness-, anger-provoking and neutral pictures from the International Affective Picture System (IAPS) were used. Data analysis was performed with statistical parametric mapping (P < 0.05). Paired t-test comparisons for each condition between medicated and unmedicated states showed, to negative valence paradigms, decrease in brain activity in the amygdala when participants were medicated. We also demonstrated, across both positive and negative valence paradigms, consistent decreases in brain activity in the medicated state in the anterior cingulate gyrus and insula. This is the first report of modulatory effects of repeated antidepressant use on the central representation of somatic states in response to emotions of both negative and positive valences in healthy individuals. Also, our results corroborate findings of antidepressant-induced temporolimbic activity changes to emotion-provoking stimuli obtained in studies of subjects treated acutely with such agents.
Laypersons' Responses to the Communication of Uncertainty Regarding Cancer Risk Estimates
Authors: Han Paul K. J. , Klein William M. P. , Lehman Thomas C. , Massett Holly , Lee Simon C. , Freedman Andrew N.
Published: May 2009

Objective . To explore laypersons' responses to the communication of uncertainty associated with individualized cancer risk estimates and to identify reasons for individual differences in these responses. Design . A qualitative study was conducted using focus groups. Participants were informed about a new colorectal cancer risk prediction model, and presented with hypothetical individualized risk estimates using presentation formats varying in expressed uncertainty (range v. point estimate). Semistructured interviews explored participants' responses to this information. Participants and Setting . Eight focus groups were conducted with 48 adults aged 50 to 74 residing in 2 major US metropolitan areas, Chicago, IL and Washington, DC. Purposive sampling was used to recruit participants with a high school or greater education, some familiarity with information technology, and no personal or immediate family history of cancer. Results . Participants identified several sources of uncertainty regarding cancer risk estimates, including missing data, limitations in accuracy and source credibility, and conflicting information. In comparing presentation formats, most participants reported greater worry and perceived risk with the range than with the point estimate, consistent with the phenomenon of ``ambiguity aversion.'' However, others reported the opposite effect or else indifference between formats. Reasons suggested by participants' responses included individual differences in optimism and motivations to reduce feelings of vulnerability and personal lack of control. Perceptions of source credibility and risk mutability emerged as potential mediating factors. Conclusions . Laypersons' responses to the communication of uncertainty regarding cancer risk estimates differ, and include both heightened and diminished risk perceptions. These differences may be attributable to personality, cognitive, and motivational factors.
How Far Do You Go? Efficient Searching for Indirect Evidence
Authors: Hawkins Neil , Scott David A. , Woods Beth
Published: May 2009

Background. Indirect evidence is particularly valuable in health care decision making when direct trial evidence comparing relevant treatments is absent or limited. Current approaches using a predetermined set of comparators in the search query may fail to identify all relevant indirect evidence. Purpose. To present a framework for the efficient design of search strategies for identifying clinical trials providing indirect evidence for a treatment comparison. Findings. The authors present 2 search strategies that differ from traditional search strategies in using a series of iterative searches to identify the set of relevant comparators. In both, the comparators included in each search are determined by the results of previous searches. For a given number of searches, the strategies presented will find all indirect comparisons that include a certain number of comparators linking the treatments of interest. Methods of estimating the value of indirect evidence via a given number of comparators linking the treatments of interest are presented, thus allowing the burden of additional searching to be traded off against the likely impact of finding more distant comparisons. A practical illustration of the search strategies in the context of informing a network meta-analysis of second-line treatments for non-small cell lung cancer is presented. Conclusions. The iterative strategies presented offer a means of identifying such evidence and allow the researcher to determine the optimal scope of the search by estimating the value of additional indirect evidence.
The Effect of Erroneous Computer Interpretation of ECGs on Resident Decision Making
Authors: Southern William N. , Arnsten Julia Hope
Published: May 2009

Background . The use of computer interpretations of electrocardiograms (ECGs) as an aid to physician interpretations is widespread. Computer misinterpretations are common and negatively affect physician interpretations. Objective . To measure the effect of computer ECG misinterpretations on clinical decision making. Design . Quasi-randomized trial. Setting . Resident teaching conferences. Participants . Included 105 internal and emergency medicine residents. Intervention . After a brief case presentation, residents were asked to interpret an ECG and choose appropriate management. Residents chose from a concealed stack of handouts; some contained an erroneous computer interpretation of the ECG (citing acute ischemia), and some contained no computer interpretation. Measurements . ECG interpretations and management decisions by residents whose ECG did or did not include an erroneous computer interpretation were compared using chi-square tests. Results . The presence or absence of erroneous computer interpretations of ischemia did not significantly affect residents' ECG interpretations (P= 0.62). However, the residents whose ECGs included erroneous computer interpretations were more likely to recommend revascularization than the residents without (30% v. 10%, P= 0.01). Of those residents who read the ECG as diagnostic of ischemia, those with the erroneous computer interpretation were more likely to recommend revascularization than those without (54% v. 25%, P= 0.048). Limitations . A single ECG was used. Conclusions . Erroneous computer interpretations of ECGs affected residents' clinical decision making in the absence of an effect on the actual interpretation of the ECG. Measuring the impact of computer misinterpretations by examining only physician interpretations will underestimate the effect of computer misinterpretations on clinical decision making.
Control for Localization of Targets using Range-only Sensors
Authors: Stump Ethan , Kumar Vijay , Grocholsky Ben , Shiroma Pedro M.
Published: May 2009

We present an application of a novel framework and algorithms for: (1) conservatively and recursively incorporating information obtained through sensors that yield observations that are non-linear functions of the state; and (2) finding control inputs that continuously improve the quality of the resulting estimates. We present an experimental study of the application of our framework to mobile robots utilizing range-only sensors, and demonstrate its effectiveness in dealing with problems of target localization with one or more robots where traditional approaches involving linearization fail to consistently capture uncertainty.
Cooperative Localization for Autonomous Underwater Vehicles
Authors: Bahr Alexander , Leonard John J. , Fallon Maurice F.
Published: May 2009

This paper describes an algorithm for distributed acoustic navigation for Autonomous Underwater Vehicles (AUVs). Whereas typical AUV navigation systems utilize pre-calibrated arrays of static transponders, our work seeks to create a fully mobile network of AUVs that perform acoustic ranging and data exchange with one another to achieve cooperative positioning for extended duration missions over large areas. The algorithm enumerates possible solutions for the AUV trajectory based on dead-reckoning and range-only measurements provided by acoustic modems that are mounted on each vehicle, and chooses the trajectory via minimization of a cost function based on these constraints. The resulting algorithm is computationally efficient, meets the strict bandwidth requirements of available AUV modems, and has potential to scale well to networks of large numbers of vehicles. The method has undergone extensive experimentation, and results from three different scenarios are reported in this paper, each of which utilizes MIT SCOUT Autonomous Surface Craft (ASC) as convenient platforms for testing. In the first experiment, we utilize three ASCs, each equipped with a Woods Hole acoustic modem, as surrogates for AUVs. In this scenario, two ASCs serve as Communication/Navigation Aids (CNAs) for a third ASC that computes its position based exclusively on GPS positions of the CNAs and acoustic range measurements between platforms. In the second scenario, an undersea glider is used in conjunction with two ASCs serving as CNAs. Finally, in the third experiment, a Bluefin12 AUV serves as the target vehicle. All three experiments demonstrate the successful operation of the technique with real ocean data.
Extracting Object Contours with the Sweep of a Robotic Whisker Using Torque Information
Authors: Solomon Joseph H. , Hartmann Mitra J. Z.
Published: May 2009

Several recent studies have investigated the problem of object feature extraction with artificial whiskers. Many of these studies have used an approach in which the whisker is rotated against the object through a small angle. Each small-angle “tap” of the whisker provides information about the radial distance between the base of the whisker and the object. By tapping at various points on the object, a full representation of the surface can be gradually constructed in three-dimensional space. It is clear, however, that this tapping method does not exploit useful information about object contours that could be extracted by “sweeping” the whisker against the object. Rotating the whisker against the object through a large angle permits the collection of a sequence of contact points as the whisker slips along the surface. The present paper derives an algorithm based on a numerical cantilever beam model of the whisker to measure object profile shape over a single large-angle whisker rotation using only information about torque and angle at the whisker base. The algorithm is validated experimentally using three different object shapes. As the method does not require measurement of force, it is well suited for implementation on an array of robotic whiskers to accomplish quick and precise object feature extraction.
Robot-assisted Tactile Sensing for Minimally Invasive Tumor Localization
Authors: Trejos A.L. , Jayender J. , Perri M.T. , Naish M.D. , Patel R.V. , Malthaner R.A.
Published: May 2009

The 10 mm incisions used in minimally invasive cancer surgery prevent the direct palpation of internal organs, making intraoperative tumor localization difficult. A tactile sensing instrument (TSI), which uses a commercially available sensor to measure distributed pressure profiles along the contacting surface, has been developed to facilitate remote tissue palpation. The objective of this research is to assess the feasibility of using the TSI under robotic control to reliably locate underlying tumors while reducing collateral tissue trauma. The performance of humans and a robot using the TSI to locate tumor phantoms embedded into ex vivo bovine livers is compared. An augmented hybrid impedance control scheme has been implemented on a Mitsubishi PA10-7C to perform the force/position control used in the trials. The results show that using the TSI under robotic control realizes an average 35% decrease in the maximum forces applied and a 50% increase in tumor detection accuracy when compared to manual manipulation of the same instrument. This demonstrates that the detection of tumors using tactile sensing is highly dependent on how consistently the forces on the tactile sensing area are applied, and that robotic assistance can be of great benefit when trying to localize tumors in minimally invasive surgery.
Identification of Human Limb Viscoelasticity using Robotics Methods to Support the Diagnosis of Neuromuscular Diseases
Authors: Venture Gentiane , Yamane Katsu , Nakamura Yoshihiko , Yamamoto Tomotaka
Published: May 2009

In this paper we present an original method to estimate in vivo the joint dynamics of the human limbs. The method is based on a non-invasive and painless technology making use of an optical motion capture system and an associated skeletal model to record the human motion and compute its kinematics and its dynamics. The formalism that is used for the identification is commonly used in robotics. The passive limb joints properties are modeled by enhanced spring-damper systems. The inverse dynamics is sampled along a movement to give an over-determined system. The obtained system is solved by the linear least-squares method. To perform the estimation, we place emphasis on giving indicators and requirements to interpret the obtained results, and on using painless, passive constraint-free movements that are usually performed during the clinical diagnosis of neuromuscular diseases. Finally the method is experimentally applied to two healthy subjects and five patients of neuromuscular diseases in order to estimate the upper-limb viscoelastic properties. The obtained results are discussed.
A Compact Modular Teleoperated Robotic System for Laparoscopic Surgery
Authors: Berkelman Peter , Ji Ma
Published: May 2009

Compared with traditional open surgery, minimally invasive surgical procedures reduce patient trauma and recovery time, but the dexterity of the surgeon in laparoscopic surgery is reduced owing to the small incisions, long instruments and limited indirect visibility of the operative site inside the patient. Robotic surgical systems, teleoperated by surgeons from a master control console with joystick-type manipulation interfaces, have been commercially developed yet their adoption into standard practice may be limited owing to their size, complexity, cost and time-consuming setup, maintenance and sterilization procedures. The goal of our research is to improve the effectiveness of robot-assisted surgery by developing much smaller, simpler, modular, teleoperated robotic manipulator systems for minimally invasive surgery.
The Epi.q-1 Hybrid Mobile Robot
Authors: Quaglia G. , Maffiodo D. , Franco W. , Appendino S. , Oderio R.
Published: May 2009

In this paper we propose an innovative solution for a small size hybrid mobile robot called Epi.q-1. Overall dimensions are about 160 mm x 360 mm x 280 mm (height x length x width). The Epi.q-1 robot moves on flat, steep or uneven ground. It can climb over obstacles or steps, even if they are non-uniform in size. Its operating mode adapts to ground conditions and changes accordingly: from rolling (on wheels) to stepping (on legs); thanks to its great mobility it can follow complex routes. It is easy to control with just a few actuators. Robot locomotion drive-generating units employ an original driving mechanism, where degrees of freedom (DOFs) can be limited to some extent according to the operating conditions or thanks to a switching device. Locomotion units consist of a motor linked to a gear (double epicyclical chain) and an axial device (mini-motor and lead screw system) able to lock or unlock some DOFs of the kinematic chain. Moreover, the robot locomotion unit can change its size, from small to large and vice versa, in order to be able to reach restricted spaces and to overcome even quite tall obstacles. It was experimentally tested on flat ground and slopes. It can overcome 90 mm obstacles, that are 72% of the height of the locomotion unit, and climb stairs.
The Solitude and Agony of Unbearable Shame
Authors: Rustomjee Sabar
Published: May 2009

The focus of this article is only on the very severe intensity of unbearable shame, which remains unspoken, as opposed to shame encountered in everyday life, which does not lead to longstanding, emotionally traumatic consequences.

Theoretical, as well as clinical aspects of unbearable shame, leading to `loss of face', dehumanization, severe impairment of both physical and emotional health, repeated failures in psychotherapy, or in certain circumstances, resulting in even more serious consequences, namely soul murder, overwhelming despair, leading to violence, suicide, or murder are explored. Group analysis, as well as combined group and individual psychotherapy frameworks, as used for the management of these patients, are discussed.

A study of the complexities of unbearable shame is made with reference to the works of Paul Mollon (2002), James Gilligan (2000), Donald Nathanson (1987), Helen Block Lewis (1971), Michael Lewis (1975) and others.
Analytical Investigation and Comparative Assessment of Interphase Influence on Elastic Behavior of Fiber Reinforced Composites
Authors: Gohil Piyush P. , Shaikh A.A.
Published: May 2009

Interfacial interactions and interphases play a key role in all fiber reinforced composites. However, a clear distinction must be made between interface and interphase. Interphase becomes interface if its thickness decreases to zero. In most of the available micromechanical models the interface is considered perfect (no interphase). However, such a condition is hardly fulfilled in real composites. It is possible to find the volume of interphase by using DSC or identification of interphase region using SEM or some other sophisticated instrument techniques as it is a region created between the two main phase of a composite. All these techniques require special technical skill. In the present study attempt is made to identify the existence of the interphase region in fiber matrix composites using SEM. It was also decided to develop an equation for volume fraction and thickness of interphase by considering the composite as three-phase RVE. Developed equations of interphase volume fraction was used by considering the soft and stiff interphase parameters. Comparisons were made to study elastic behavior of fiber reinforced composites in longitudinal and transverse directions with available experimental data and published model in the literature and they are in good agreement.
Macroscale Simulation of Fiber Bed Impregnation Utilizing Microscale Material Properties
Authors: Brennan Kelly P. , Walrath David E.
Published: May 2009

A numerical process model was created to simulate unsteady flow through nonhomogeneous unidirectional fibrous media. Permeabilities calculated at the fiber level were applied over small spatial and temporal regions to improve accuracy of macroscopic analysis. Consideration was given to non-ideal aspects of the fiber bed, especially fiber array randomness and fiber bed compressibility. Experimental results indicated that permeant driven fiber compaction had a major influence on flow front advancement. Overall, the process model developed in this work showed marked improvement in predicting flow front locations over a standard bulk property model.
Effect of Wood Species and Coupling Agent on Mechanical Properties of Wood Flour/HDPE Composites
Authors: Zabihzadeh Seyed Majid , Dastoorian Foroogh , Ebrahimi Ghanbar
Published: May 2009

As the major component of WPCs, wood flour species plays an important role on the properties of the resulting composites. The effect of wood species as filler and reinforcement and MAPE as compatibilizer on mechanical properties of wood flour/high-density polyethylene composite was investigated. The wood species used in this study were loblolly pine and hybrid Euro-American poplar. The mechanical properties such as tensile properties and notched impact toughness were tested. Poplar flour provides an improvement in tensile strength, tensile modulus, tensile energy absorption, and failure strain over pine. Tensile strength of both the composites was much higher for compatibilized composites as compared with uncompatibilized ones. For the pine composites, tensile modulus improvements were attained even with 1% compatibilizer. There was little difference in the properties obtained between the 1% and 2% compatibilizer. For the poplar composites, adding 1% compatibilizer did not have significant effect on tensile modulus and there was a significant drop in tensile modulus with further 2% increase in the compatibilizer. Wood species and compatibilizer percent did not have significant effect on the notched Izod toughness.