bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenomenal Permanence and the Development of Predictive Tracking in Infancy
Authors: Bertenthal Bennett I. , Longo Matthew R. , Kenny Sarah
Published: February 2007

The perceived spatiotemporal continuity of objects depends on the way they appear and disappear as they move in the spatial layout. This study investigated whether infants' predictive tracking of a briefly occluded object is sensitive to the manner by which the object disappears and reappears. Five‐, 7‐, and 9‐month‐old infants were shown a ball rolling across a visual scene and briefly disappearing via kinetic occlusion, instantaneous disappearance, implosion, or virtual occlusion. Three different measures converged to show that predictive tracking increased with age and that infants were most likely to anticipate the reappearance of the ball following kinetic occlusion. These results suggest that infants' knowledge of the permanence and nonpermanence of objects is embodied in their predictive tracking.
Nature and dynamics of appropriability: strategies for appropriating returns on innovation
Authors: Hurmelinna‐Laukkanen Pia , Puumalainen Kaisu
Published: February 2007

The appropriability regime represents a combination of available and effective means of protecting intangibles and innovations, their profitability, and the increased rents due to research and development. It has a central role in appropriating returns on investment, but the nature of appropriability and the strategies for appropriation may not be fully known to managers, or even to researchers. The aim in this study, therefore, is to categorise the appropriability regime by extending, combining and complementing previous research. We also conducted a survey among 299 companies in order to determine the roles, availability, strength and efficiency of appropriability mechanisms. Such mechanisms offer institutional protection in the form of intellectual property rights, contracts and labour legislation, tacitness of knowledge, lead‐time, practical secrecy and human‐resource management. As a result, we suggest a conceptual clarification of the appropriability regime, and offer empirical evidence to increase understanding of the appropriation of returns on innovation.
Gendered production spaces and crop varietal selection: Case study in Yucatán, Mexico
Authors: Lope‐Alzina Diana Gabriela
Published: February 2007

This paper examines the influence of gender relations and gendered domains on maize and squash varietal selection in a village in Yucatán State, southeast Mexico. Results of the exploratory study indicate that the traditional production spaces of homegardens and agricultural fields are complementary gendered domains of varietal maintenance for both crops although with different cropping patterns, while a ‘new’ space, of land allocated to some families for future residential construction (terreno) is in the meantime a jointly worked agricultural domain. Women’s labour, knowledge and preferences predominate in post‐harvest processes. Fieldwork revealed that neither men nor women are independent decision‐makers, planning what to grow, where and in what amounts, but that in most aspects of farming the interests of both are accommodated within the household’s production spaces.
The Burden of Labour Costs in Mexico
Authors: Rojas Gabriel Montes , Santamaría Mauricio
Published: February 2007

Abstract.  We analysed labour costs in Mexico and evaluated their impact in terms of firm performance. Using a new survey, we studied how firms chose to conduct a firing procedure (i.e. mandatory payment, negotiation, or legal dispute) and the actual costs derived from that decision. We found that firms that negotiate have, on average, lower costs. This may mean that workers subvaluate the legal benefits. Moreover, legal disputes may increase firing costs by 50 per cent. We contributed to the analysis of the impact of such costs on employment and found that, when firms negotiate or pay higher costs, this decreases the level of employment. We also analysed the impact of Social Benefits on employment using an industrial survey. We found that a 10 per cent increment in these benefits may have a negative long‐term impact of 9 per cent on the level of employment.
Life cycles of growing organizations: A review with implications for knowledge and learning
Authors: Phelps Robert , Adams Richard , Bessant John
Published: February 2007

Conceptualizing growth trajectories of organizations in organismic terms describing transitions through a series of stages, from birth to maturity, has considerable intuitive appeal. Recently, the assumptions underpinning the life‐cycle perspective (growth is linear, sequential, deterministic and invariant) have been argued not to pertain to organizations. This paper reviews the literature on life‐cycle growth models, traces the development of a growing sophistication of conceptualizing growth and highlights some of the limitations of the literature. The authors make a contribution by proposing an alternative conceptual framework for thinking about growing businesses. The framework consists of two dimensions. First, a typology of key issues that are likely to be faced by all growing firms, and the discussion is shaped by M. Gladwell's (The Tipping Point: How Little Things Can Make a Big Difference. Boston: Little Brown, 2000) notion of ‘tipping points’. The second dimension is developed by drawing on the knowledge management literature and the concept of absorptive capacity (Cohen, W.M. and Levinthal, D.A. (1990). Absorptive capacity: a new perspective on learning and innovation. Administrative Science Quarterly, 35, 128–152). This concept is applied to a discussion of the state of an organization regarding its ability to absorb and use new knowledge. Further, it is suggested that the framework has value for both policy and practice and can be used for the design and specification of interventional support and, to identify and evaluate their impact. If interventions are to help firms to grow, they must provide the right knowledge or support in forms that the firm can utilize. Together, these two dimensions provide a framework to examine firm growth issues and to analyse the effectiveness of different interventions on firms in different states within this framework.
Liquidity Commonality in the London Stock Exchange
Authors: Galariotis Emilios C. , Giouvris Evangelos
Published: February 2007

Abstract:  A number of events such as the international market crash of October 1987 and the 1997 East Asian crisis show that individual firm liquidity is affected by market‐wide factors. However, research in systematic liquidity is still at an embryonic stage and given the gap in the literature, the paper offers first time evidence (to the best of our knowledge) on the presence of systematic liquidity in the UK using FTSE100 and FTSE250 stocks. The unique setting of the London Stock Exchange as regards changes in trading regimes, allows an original answer as to whether changes in the nature of market making from obligatory to non‐obligatory, affect commonality in liquidity. Results indicate that commonality is quite strong for FTSE100 stocks at individual and portfolio level, while for the FTSE250 it is strong only at portfolio level. Overall commonality is on average similar across trading regimes, irrespective of the nature of the provision of liquidity.
Protecting Europe's Critical Infrastructures: Problems and Prospects
Authors: Fritzon Åsa , Ljungkvist Kristin , Boin Arjen , Rhinard Mark
Published: February 2007

The European Union has become increasingly involved with protecting the security and safety of European citizens. The latest addition to this new policy space is critical infrastructure protection (CIP) at the EU level. A central role for the EU in guarding against infrastructural breakdowns and preparing for failures may seem self‐evident. In reality, the precise nature of such a role remains unclear. Moreover, enthusiastic rhetoric is not always matched by firm action. This article surveys what the EU has in place in terms of CIP and identifies outstanding issues for debate.
Morphological correlates of aquatic and terrestrial locomotion in a semi‐aquatic frog, Rana esculenta: no evidence for a design conflict
Authors: Nauwelaerts Sandra , Ramsay Jason , Aerts Peter
Published: February 2007

Semi‐aquatic frogs are faced with an unusual locomotory challenge. They have to swim and jump using the same apparatus, i.e. the hind limbs. Optimization of two tasks that require mutually incompatible morphologies or physiologies cannot occur simultaneously. In such cases, natural selection will result in some compromise, i.e. an intermediate phenotype that can perform both tasks reasonably well, but its performance will never match that of a specialized phenotype. We found no direct evidence for a trade‐off between jumping and swimming performance nor for a coupled optimization. This could be due to the importance of overall quality, as suggested by the fact that some frogs possess greater overall muscularity than others, irrespective of their body size. Another explanation could be that some morphological characteristics have a positive effect on both locomotor modes and others show a trade‐off effect. The net effect of these characteristics could result in an overall absence of correlation between the two locomotor performances. Size has a great influence on the morphological data and on jumping performance, but not if performance is expressed as velocity. The body shape of an anuran is conservative and scales mostly isometrically.
The sympathetic postganglionic and sensory innervation of oviducal magnum in hen: a choleratoxin subunit B‐conjugated horseradish peroxidase study
Authors: Liu Jinxiong , Wang Wenjie , Feng Yamei , Li Meiying , Bao Huijun , Chen Qiusheng
Published: February 2007

The anatomy of the extrinsic innervation of the avian magnum has not been accurately demonstrated previously. In the present study, choleratoxin subunit B‐conjugated horseradish peroxidase (CB‐HRP) was used as a retrograde tracer to determine the sympathetic postganglionic and sensory innervation of the magnum of hens. With regard to the sympathetic postganglionic innervation, following CB‐HRP injections under the serosa of the magnum, CB‐HRP‐positive neurons were found bilaterally in the C12–LS13 ganglia of the sympathetic chain, splanchnic ganglia and adrenal ganglia. The number of labelled neurons in the left ganglia of the sympathetic chain and splanchnic ganglia was approximately 2.1 times that in the right ganglia. This suggests that the unilateral magnum is bilaterally innervated with sympathetic postganglionic nerves, the left nerves being predominant. With regard to the sensory innervation, following tracer injections, CB‐HRP‐positive neurons were found bilaterally in the spinal ganglia C13–LS12, jugular ganglia and nodose ganglia. The number of positive cells in the left ganglia was about 2.2 times that in the right ganglia. In the spinal ganglia, 85.6% of the labelled neurons were in the T5–LS2 and LS8–LS11 ganglia. These results suggest that the sensory nerve fibres of the magnum reach the central nervous system principally via two groups of spinal ganglia and vagus nerves, and that the innervation is bilateral although the left‐hand route predominates. Moreover, 45.7% of all the CB‐HRP‐labelled neurons were found in the rectal region of the intestinal nerve of Remak (INR), which suggests that the INR plays a very important role in the functional regulation of the magnum.
Ethiopia's Coffee Sector: A Bitter or Better Future?
Authors: PETIT NICOLAS
Published: February 2007

Coffee, Ethiopia's largest export crop, is the backbone of the Ethiopian economy. The Ethiopian coffee sector is highly dependent on international prices and affected by the structure and workings of the world coffee market. In this context, this paper seeks to identify what can be done in Ethiopia to improve the performance of the sector so as to yield benefits for the government and the estimated 15 million people dependent on coffee in the country. The paper argues that despite a limited room for manoeuvre, Ethiopia has not yet fully exploited its position as the producer of some of the best coffees in the world. A number of competitive advantages may still be seized if quality and consistency are guaranteed. In order to maximize this potential, and on the basis of a critical analysis of government policies and donor interventions in the sector, a number of recommendations are made.
National Vocational Qualifications: the candidates’ experience
Authors: Isaac Susan
Published: February 2007

Purpose:  To examine the experience of studying for an National Vocational Qualification (NVQ) by past and present candidates in the library and information science sector, their reasons for choosing this qualification and its impact on completion.

Methodology:  Following a review of the literature, a number of NVQ candidates were interviewed using a semi‐structured questionnaire. Candidates were contacted via e‐mail through NVQ Centres and the LondonLinks e‐mail list. There is a focus on health libraries as the flexibility and work‐based nature of NVQs enable more staff to access training and education in this sector, despite the not uncommon low levels of staffing.

Results:  NVQ Centres have gained experience since NVQs were launched 10 years ago. More support is offered to candidates and a number of issues such as isolation, are no longer a problem. An interesting result was the high number of candidates who had gone on to higher education following the completion of an NVQ.

Conclusions:  The NVQ is a useful method of providing staff with an opportunity to gain a recognized qualification. A significant number of candidates reported that the NVQ was ultimately a positive experience that improved their working practices. It can be an important first step for non‐professional staff, but the future remains uncertain.
Evaluating the impact of library user training programmes across Thames Valley Strategic Health Authority in the UK
Authors: Trinder Valerie M , Fleet Geoffrey E , Gray Anne E
Published: February 2007

Background:  This study was undertaken to provide evidence that library outreach projects in the NHS in the Thames Valley Strategic Health Authority area were effective and could justify continued funding.

Objectives:  The object was to assess whether information literacy skills training taken up by health professionals impacts on their confidence and skills in using electronic sources of health information.

Method:  A total of 487 health professionals taking up training on a voluntary basis were assessed by completing a self‐assessment questionnaire prior to and after training to establish their information literacy skills and confidence levels. Of these, 223 trainees (46%) also returned 6‐week follow‐up questionnaires.

Results:  Results showed that 464 trainees (95%) intended to apply what they had learnt in a variety of ways; use of specific resources greatly increased after training and confidence in using them increased substantially. Use of search techniques increased considerably overall, whereas use of Google decreased.

Conclusions:  The major findings of this research are that training health‐care personnel in the use of electronic resources impacts positively on their information literacy skills and confidence, and that the information available to them is considered to have potential value across health‐care practice.
Effectiveness of information skills training and mediated searching: qualitative results from the EMPIRIC project
Authors: Brettle Alison , Hulme Claire , Ormandy Paula
Published: February 2007

Objectives:  To explore library staff and health professionals’ views on the effectiveness of information skills training and librarian mediated searching as methods of providing information for patient care. This is the second article describing the Effective Methods of Providing InfoRmation for patIent Care (EMPIRIC) project. The first paper, in a previous issue of this journal (Brettle et al. The costs and effectiveness of information skills training and mediated searching: quantitative results for the EMPIRIC project. Health Information and Libraries Journal 2006, 23, 239–247) describes the quantitative results.

Methods:  A questionnaire survey to library staff and health professionals in the North West. Data was collected on perceptions of services, satisfaction and service usage. Statistical data were analysed using the Statistical Package for the Social Sciences (SPSS) and qualitative data using thematic analysis.

Results:  Both information skills training and mediated searches are perceived by library staff and health professionals to be effective. There is strong support for mediated searches carried out on behalf of the health professional and information skills training to enable them to carry out their own searches. The results provide insights into the effectiveness of the services and the factors that make them effective.

Conclusions:  Evidence and stakeholders views support the provision of both information skills training and mediated search services. Both services are valued by users who see them as complementary methods of obtaining information depending on their needs at different times.
Characterization of new SSR‐EST markers in cod, Gadus morhua
Authors: WEISS EMILY , BENNIE MICHAEL , HODGINS‐DAVIS ANDREA , ROBERTS STEVEN , GERLACH GABRIELE
Published: February 2007

For years, fishermen have noted that cod (Gadus morhua) within the Georges Bank Atlantic fishery spawn multiple times annually with peaks in the spring and in the fall. To evaluate the hypothesis that these differences in reproductive behaviour reflect genetically different spawning populations, we identified eight polymorphic simple sequence repeats within expressed sequence tags (ESTs). Previously, only a few genetic markers have been informative for distinguishing between cod populations of the Northwest Atlantic. The development of additional markers from ESTs will be a valuable tool to improve our understanding of population structure in this commercially important species.
Sexual conflict over parental care in Penduline Tits Remiz pendulinus: the process of clutch desertion
Authors: VAN DIJK RENÉ E. , SZENTIRMAI ISTVÁN , KOMDEUR JAN , SZÉKELY TAMÁS
Published: February 2007

Do the two parents at a nest make simultaneous decisions whether to care for their offspring or to desert? If a single parent is sufficient for rearing young, one parent (typically, the male) may desert and reproduce with a new mate within the same breeding season, leaving the other parent with the brunt of care. As each parent is expected to maximize its own reproductive success, the interests of the two parents do not necessarily coincide, and a sexual conflict over care may emerge. Here we investigate the process of clutch desertion in a small passerine bird, the Penduline Tit Remiz pendulinus. Among birds, this species has a remarkably variable breeding system, because a single parent (either the male or the female) may provide the full care of the young, whereas about 30% of clutches are abandoned by both parents. First, we show that biparental desertion occurs within a single day in 73.7% of the clutches (n = 14), whereas desertion decisions are sequential in 26.3% of the clutches (n = 5) (male first: 10.5% (n = 2); female first: 15.8% (n = 3); n = 19 clutches in total). Secondly, we observed the behaviour of both parents before desertion, and investigated whether desertion can be predicted from their behaviour. However, neither singing nor nest‐building behaviour predicted whether the male or the female would desert. We therefore suggest that biparental desertion may be simultaneous by male and female in our population of Penduline Tits. Furthermore, the parents do not appear to signal their intention to desert their mate. We argue that the parents’ interest may be actually to disguise their intention to desert.
Vertebrate aging research 2006
Authors: Austad Steven N.
Published: February 2007

This Hot Topics review, the first in a projected annual series, discusses those articles, published in the last year, which seem likely to have a major impact on our understanding of the aging process in mammals and the links between aging and late‐life illnesses. The year's highlights include studies of oxidation damage in the very‐long‐lived naked mole‐rat, and of caloric restriction in monkeys, humans, and growth hormone‐unresponsive mice. Two studies of resveratrol, one showing its ability to extend lifespan in a short‐lived fish, the other demonstrating beneficial effects in mice subjected to a diet high in fat, may well be harbingers of a parade of intervention studies in the coming decade.
UNDERSTANDING REGIONAL POVERTY AND INEQUALITY TRENDS IN CHINA: METHODOLOGICAL ISSUES AND EMPIRICAL FINDINGS
Authors: Wan Guanghua
Published: February 2007

This paper focuses on methodological and empirical issues in analyzing regional poverty and inequality trends in China. It provides a time profile of China's regional inequality, outlines the latest development in inequality decomposition techniques, introduces six papers in this special issue of the Review, and finally offers suggestions for future research.
ESTIMATING INCOME INEQUALITY IN CHINA USING GROUPED DATA AND THE GENERALIZED BETA DISTRIBUTION
Authors: Chotikapanich Duangkamon , Rao D. S. Prasada , Tang Kam Ki
Published: February 2007

There are two main types of data sources of income distributions in China: household survey data and grouped data. Household survey data are typically available for isolated years and individual provinces. In comparison, aggregate or grouped data are typically available more frequently and usually have national coverage. In principle, grouped data allow investigation of the change of inequality over longer, continuous periods of time, and the identification of patterns of inequality across broader regions. Nevertheless, a major limitation of grouped data is that only mean (average) income and income shares of quintile or decile groups of the population are reported. Directly using grouped data reported in this format is equivalent to assuming that all individuals in a quintile or decile group have the same income. This potentially distorts the estimate of inequality within each region. The aim of this paper is to apply an improved econometric method designed to use grouped data to study income inequality in China. A generalized beta distribution is employed to model income inequality in China at various levels and periods of time. The generalized beta distribution is more general and flexible than the lognormal distribution that has been used in past research, and also relaxes the assumption of a uniform distribution of income within quintile and decile groups of populations. The paper studies the nature and extent of inequality in rural and urban China over the period 1978 to 2002. Income inequality in the whole of China is then modeled using a mixture of province‐specific distributions. The estimated results are used to study the trends in national inequality, and to discuss the empirical findings in the light of economic reforms, regional policies, and globalization of the Chinese economy.
A Common SCN5A Variant Alters the Responsiveness of Human Sodium Channels to Class I Antiarrhythmic Agents
Authors: SHURAIH MOSSAAB , AI TOMOHIKO , VATTA MATTEO , SOHMA YOSHIRO , MERKLE EILEEN M. , TAYLOR ERICA , LI ZHAOHUI , XI YUTAO , RAZAVI MEHDI , TOWBIN JEFFREY A. , CHENG JIE
Published: February 2007

Background: The potential pathophysiological role of common SCN5A polymorphisms in cardiac arrhythmias has been increasingly recognized. However, little is known about the impact of those polymorphisms on the pharmocological response of hNav1.5 to various antiarrhythmic agents.

Methods and Results: The known SCN5A polymorphism, S524Y, was studied in comparison with the wild type (WT) define the SCN5A‐Q1077del variant. The ion channel gating kinetics and pharmacology were evaluated using whole‐cell patch‐clamp methods in HEK‐293 cells. Consistent with a previous report, the basal ion channel gating kinetics of S524Y were indistinguishable from the WT. Quinidine (20 μM) caused similar extent of tonic block reduction of sodium currents at –120 mV in WT and S524Y. Surprisingly, quinidine (20 μM) exerted a more use‐dependent block by a 10 Hz pulse train in S524Y than in WT at 22°C (Ki: WT, 51.3 μM; S524Y, 20.3 μM). S524Y significantly delayed recovery from the use‐dependent block, compared with the WT (τ= 88.6 ± 7.9 s vs 41.9 ± 6.6 s, P < 0.005). Under more physiological conditions using a 2 Hz pulse train at 37°C, S524Y similarly enhanced the use‐dependent block by quinidine. In addition, S524Y enhanced the use‐dependent block by flecainide (12.5 μM), but not by mexiletine (100 μM).

Conclusion: A common SCN5A polymorphism, S524Y, can enhance a use‐dependent block by class Ia and Ic antiarrhythmic agents. Our findings may have clinical implications in pharmacological management of cardiac arrhythmias since this common SCN5A polymorphism might be a contributing factor to the variable antiarrhythmic response.
Intraoperative Transesophageal Echocardiographic Diagnosis of a Stuck Bioprosthetic Mitral Valve Leaflet
Authors: Singh Anurag , Nanda Navin C. , Kirklin James K.
Published: February 2007

Stuck (immobilized) leaflet of a metallic mitral prosthetic valve due to obstruction by mitral subvalvular apparatus is a well recognized complication after placement of prosthetic valves. However, a stuck mitral valve leaflet involving a bioprosthetic valve has not been reported so far most likely because of increased pliability of tissue leaflets. We describe the first case of a stuck bioprosthetic mitral valve leaflet in which intraoperative transesophageal echocardiography was useful to make a definitive diagnosis and helped to resolve the problem immediately.
Pulmonary Hypertension and Left Heart Function: Insights from Tissue Doppler Imaging and Myocardial Performance Index
Authors: Chang Shu‐Mei , Lin Chiung‐Chih , Hsiao Shih‐Hung , Lee Chiu‐Yen , Yang Shu‐Hsin , Lin Shih‐Kai , Huang Wei‐Chen
Published: February 2007

Background: As a consequence of a leftward shift of the interventricular septum and of pericardial restraint, related to the degree RV dilatation, left heart function would be influenced after pulmonary hypertension and right heart failure. Methods and Results: We enrolled 70 patients with pulmonary artery systolic pressure (PASP) more than 30 mmHg: 40 patients with PASP between 30 and 60 mmHg (Group 2), 30 patients with PASP more than 60 mmHg (Group 3). Another 70 patients with normal heart performance and PASP less than 30 mmHg served as the control group (Group 1). Myocardial performance index (MPI), isovolumic contraction time (IVCT), and isovolumic relaxation time (IVRT) were obtained by tissue Doppler imaging (TDI). PASP correlated negatively to peak systolic velocity of lateral tricuspid annulus (RV‐Sm) and RVEF. The MPI of RV and LV in patients with severe pulmonary hypertension (Group 3) became higher as the result of the prolongation of IVRT. The higher E/Em (peak early‐diastolic mitral‐inflow velocity divided by early‐diastolic velocity of mitral annulus) in pulmonary hypertension indicated diastolic dysfunction of LV. The decline of left ventricular ejection fraction, and also right ventricular ejection fraction, suggested LV systolic dysfunction after pulmonary hypertension. The LV‐MPI truly reflected LV systolic and diastolic dysfunction in patients with pulmonary hypertension. In multiple linear regression analysis, LV‐MPI was independently associated only with RV‐MPI (Beta 0.47, P < 0.0001). Conclusion: The result infers that the systolic and diastolic function of LV declined, following pulmonary hypertension.
Preserved Windkessel Function in Patients Following Reduction Aortoplasty of the Ascending Aorta
Authors: Bail Dorothee H.L. , Walker Tobias , Gruler Miriam , Ziemer Gerhard
Published: February 2007

Objective: Reduction ascending aortoplasty (RAA) is a controversial procedure. Agreement has not yet been made regarding the indication for surgery and surgical technique. The goal of this study was to examine the long‐term outcome of RAA without external support, and to compare the accuracy of transthoracic echocardiographic with computed tomographic (CT) measurements. Of particular interest was whether the important elastic properties of the aorta, the Windkessel function, is preserved following reduction aortoplasty of the ascending aorta without external wrapping. Methods: Ninety‐eight patients with dilation of the ascending aorta underwent reduction aortoplasty with concomitant cardiac procedures. Fifty‐four patients were available for follow‐up. Measurement of the ascending aortic diameter was performed prior to and directly following surgery, and 37 months postoperatively (range: 10–96 months). Both echocardiography and CT imaging were performed. The elastic properties of the ascending aorta were determined by measuring the distension of the ascending aorta during diastole and systole by means of transthoracic echocardiography. Fifteen patients with graft replacement of the ascending aorta were examined, and the control group contained 11 healthy volunteers. Results: The diameter of the ascending aorta was significantly reduced in all patients who had undergone RAA. The change in diameter between diastole and systole was 3 mm in patients with reduction aortoplasty. Patients with graft replacement had a change of only 0.07 cm. There was no relevant increase (2 mm) in diameter at follow‐up. Echocardiographic and CT measurements of the aortic diameter did not differ. Conclusions: RAA without external wrapping shows good long‐term results in patients with a dilated ascending aorta who underwent concomitant cardiac procedures. Echocardiography is very accurate in measuring the ascending aortic diameter, which makes it a cost‐effective diagnostic tool. Moreover, ascending aortoplasty without external wrapping preserves the important elastic properties, namely the Windkessel function. Follow‐up of the cardiac function and aortic diameter can be performed easily and precisely in the outpatient setting.
Clinical and Echocardiographic Risk Factors for Embolization in the Presence of Left Atrial Thrombus
Authors: Kavlak Ela Sahinbas , Kucukoglu Hayriye , Yigit Zerrin , Okcun Baris , Baran Turker , Ozkan Alev Arat , Kucukoglu Serdar
Published: February 2007

Aims: The aim of our study was to evaluate the factors leading to embolization in patients with left atrial thrombi (LAT). With this purpose, we retrospectively analyzed clinical, transthoracic, transesophageal echocardiographic data of patients with LAT in the transesophageal echocardiographic evaluation. Methods and Results: One hundred ninety‐two patients with LAT not on anticoagulant therapy were divided into two groups according to the presence of prior ischemic stroke. The group with ischemic stroke included more patients with sinus rhythm and less patients with mitral stenosis. They had smaller left atrial diameter, more left atrial appendage spontaneous echo‐contrast, higher appendage ejection fraction, and emptying velocity. Conclusion: Once the thrombus has been formed, cerebral embolization seems to be higher in patients with relatively preserved appendage ejection fraction and emptying velocity. Presence of atrial appendage spontaneous echo‐contrast also favor embolization. Factors leading to embolization seem to differ in some respects from the causes of thrombus formation.
Two‐Dimensional Assessment of Right Ventricular Function: An Echocardiographic–MRI Correlative Study
Authors: Anavekar Nagesh S. , Gerson David , Skali Hicham , Kwong Raymond Y. , Kent Yucel E. , Solomon Scott D.
Published: February 2007

Background: While echocardiography is used most frequently to assess right ventricular (RV) function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Hence, quantitative estimation of RV function has proven difficult in clinical practice. Objective: We sought to determine which commonly used echocardiographic measures of RV function were most accurate in comparison with an MRI‐derived estimate of RVEF. Methods: We analyzed RV function in 36 patients who had cardiac MRI studies and echocardiograms within a 24 hour period. 2D parameters of RV function—right ventricular fractional area change (RVFAC), tricuspid annular motion (TAM), and transverse fractional shortening (TFS) were obtained from the four‐chamber view. RV volumes and EFs were derived from volumetric reconstruction based on endocardial tracing of the RV chamber from the short axis images. Echocardiographic assessment of RV function was correlated with MRI findings. Results: RVFAC measured by echocardiography correlated best with MRI‐derived RVEF (r = 0.80, P < 0.001). Neither TAM (r = 0.17; P = 0.30) nor TFC (r = 0.12; p< 0.38) were significantly correlated with RVEF. Conclusions: RVFAC is the best of commonly utilized echocardiographic 2D measure of RV function and correlated best with MRI‐derived RV ejection fraction. Condensed Abstract: While echocardiography is used most frequently to assess RV function in clinical practice, echocardiography is limited in its ability to provide an accurate measure of RV ejection fraction (RVEF). Using cardiac MRI, RV fractional area change (RVFAC), determined either by MRI or echocardiography, was found to correlate best with MRI‐derived RVEF.
IMAGING DIAGNOSIS—METASTATIC HEMANGIOSARCOMA CAUSING CEREBRAL HEMORRHAGE IN A DOG
Authors: DENNLER MATTHIAS , LANGE EVA‐MARIA , SCHMIED OLIVER , KASER‐HOTZ BARBARA
Published: February 2007

A 9‐year‐old male Appenzeller mountain dog had progressive severe ataxia and central vestibular syndrome that was localized clinically to the brain stem. The cerebrospinal fluid characteristics were suggestive of hemorrhage into the subarachnoid space. On computed tomography (CT), hyperattenuating masses were found in the left lateral ventricle extending into the cerebrum, and another involving the cerebellum and brainstem. The hyperattenuation of the masses in noncontrast images and the absence of contrast enhancement were consistent with hemorrhage. The dog underwent euthanasia. A metastatic hemangiosarcoma in the brain, causing acute bleeding in the left lateral ventricle and the brainstem, was found. A solitary mass in the left myocardium was thought to be the primary site. CT characteristics of intracranial hemorrhage are reviewed.
Gene silencing at the nuclear periphery
Authors: Shaklai Sigal , Amariglio Ninette , Rechavi Gideon , Simon Amos J.
Published: February 2007

The nuclear envelope (NE) is composed of inner and outer nuclear membranes (INM and ONM, respectively), nuclear pore complexes and an underlying mesh like supportive structure – the lamina. It has long been known that heterochromatin clusters at the nuclear periphery adjacent to the nuclear lamina, hinting that proteins of the lamina may participate in regulation of gene expression. Recent studies on the molecular mechanisms involved show that proteins of the nuclear envelope participate in regulation of transcription on several levels, from direct binding to transcription factors to induction of epigenetic histone modifications. Three INM proteins; lamin B receptor, lamina‐associated polypeptide 2β and emerin, were shown to bind chromatin modifiers and/or transcriptional repressors inducing, at least in one case, histone deacetylation. Emerin and another INM protein, MAN1, have been linked to down‐regulation of specific signaling pathways, the retino blastoma 1/E2F MyoD and transforming growth factor beta/bone morphogenic protein, respectively. Therefore, cumulative data suggests that proteins of the nuclear lamina regulate transcription by recruiting chromatin modifiers and transcription factors to the nuclear periphery. In this minireview we describe the recent literature concerning mechanisms of gene repression by proteins of the NE and suggest the hypothesis that the epigenetic ‘histone code’, dictating transcriptional repression, is ‘written’ in part, at the NE by its proteins. Finally, as aberrant gene expression is one of the mechanisms speculated to underlie the newly discovered group of genetic diseases termed nuclear envelopathies/laminopathies, elucidating the repressive role of NE proteins is a major challenge to both researchers and clinicians.
Structure of coenzyme F420H2 oxidase (FprA), a di‐iron flavoprotein from methanogenic Archaea catalyzing the reduction of O2 to H2O
Authors: Seedorf Henning , Hagemeier Christoph H. , Shima Seigo , Thauer Rudolf K. , Warkentin Eberhard , Ermler Ulrich
Published: February 2007

The di‐iron flavoprotein F420H2 oxidase found in methanogenic Archaea catalyzes the four‐electron reduction of O2 to 2H2O with 2 mol of reduced coenzyme F420(7,8‐dimethyl‐8‐hydroxy‐5‐deazariboflavin). We report here on crystal structures of the homotetrameric F420H2 oxidase from Methanothermobacter marburgensis at resolutions of 2.25 Å, 2.25 Å and 1.7 Å, respectively, from which an active reduced state, an inactive oxidized state and an active oxidized state could be extracted. As found in structurally related A‐type flavoproteins, the active site is formed at the dimer interface, where the di‐iron center of one monomer is juxtaposed to FMN of the other. In the active reduced state [Fe(II)Fe(II)FMNH2], the two irons are surrounded by four histidines, one aspartate, one glutamate and one bridging aspartate. The so‐called switch loop is in a closed conformation, thus preventing F420 binding. In the inactive oxidized state [Fe(III)FMN], the iron nearest to FMN has moved to two remote binding sites, and the switch loop is changed to an open conformation. In the active oxidized state [Fe(III)Fe(III)FMN], both irons are positioned as in the reduced state but the switch loop is found in the open conformation as in the inactive oxidized state. It is proposed that the redox‐dependent conformational change of the switch loop ensures alternate complete four‐electron O2 reduction and redox center re‐reduction. On the basis of the known Si–Si stereospecific hydride transfer, F420H2 was modeled into the solvent‐accessible pocket in front of FMN. The inactive oxidized state might provide the molecular basis for enzyme inactivation by long‐term O2 exposure observed in some members of the FprA family.
Characterization of the bga1‐encoded glycoside hydrolase family 35 β‐galactosidase of Hypocrea jecorina with galacto‐β‐d‐galactanase activity
Authors: Gamauf Christian , Marchetti Martina , Kallio Jarno , Puranen Terhi , Vehmaanperä Jari , Allmaier Günter , Kubicek Christian P. , Seiboth Bernhard
Published: February 2007

The extracellular bga1‐encoded β‐galactosidase of Hypocrea jecorina (Trichoderma reesei) was overexpressed under the pyruvat kinase (pki1) promoter region and purified to apparent homogeneity. The monomeric enzyme is a glycoprotein with a molecular mass of 118.8 ± 0.5 kDa (MALDI‐MS) and an isoelectric point of 6.6. Bga1 is active with several disaccharides, e.g. lactose, lactulose and galactobiose, as well as with aryl‐ and alkyl‐β‐d‐galactosides. Based on the catalytic efficiencies, lactitol and lactobionic acid are the poorest substrates and o‐nitrophenyl‐β‐d‐galactoside and lactulose are the best. The pH optimum for the hydrolysis of galactosides is ∼ 5.0, and the optimum temperature was found to be 60 °C. Bga1 is also capable of releasing d‐galactose from β‐galactans and is thus actually a galacto‐β‐d‐galactanase. β‐Galactosidase is inhibited by its reaction product d‐galactose and the enzyme also shows a significant transferase activity which results in the formation of galacto‐oligosaccharides.
Purification and cloning of a Delta class glutathioneS‐transferase displaying high peroxidase activity isolated from the German cockroachBlattella germanica
Authors: Ma Bennett , Chang Frank N.
Published: February 2007

A highly active glutathioneS‐transferase was purified from adult German cockroaches,Blattella germanica. The purified enzyme appeared as a single band of 24 kDa by SDS/PAGE, and had a different electrophoretic mobility than, a previously identified Sigma class glutathioneS‐transferase (Bla g 5). Kinetic study of 1‐chloro‐2,4‐dinitrobenzene conjugation revealed a high catalytic rate but common substrate‐binding and cosubstrate‐binding affinities, withVmax,kcat,Kmfor 1‐chloro‐2,4‐dinitrobenzene andKmfor glutathione estimated to be 664 µmol·mg−1·min−1, 545 s−1, 0.33 mmand 0.76 mm, respectively. Interestingly, this enzyme possessed the highest activity for cumene hydroperoxide among insect glutathioneS‐transferases reported to date. Along with the ability to metabolize 1,1,1‐trichloro‐2,2‐bis(p‐chlorophenyl)ethane and 4‐hydroxynonenal, this glutathioneS‐transferase may play a role in defense against insecticides as well as oxidative stress. On the basis of the amino acid sequences obtained from Edman degradation and MS analyses, a 987‐nucleotide cDNA clone encoding a glutathioneS‐transferase (BggstD1) was isolated. The longest ORF encoded a 24 614 Da protein consisting of 216 amino acid residues. The sequence had close similarities (∼ 45–60%) to that of Delta class glutathioneS‐transferases, but had only 14% identity to Bla g 5. The putative amino acid sequence contained matching peptide fragments of the purified glutathioneS‐transferase. ELISA showed that BgGSTD1 bound to serum IgE obtained from patients with cockroach allergy, indicating that the protein may be a cockroach allergen.
Borderline ovarian tumors
Authors: GHAEMMAGHAMI Fatemeh , ASHRAF‐GANJOOIE Tahereh , IRAVANLOO Giti
Published: February 2007

Borderline ovarian tumors account for approximately 15% of all epithelial ovarian tumors. In the early 1970s, borderline tumors were categorized as either serous or mucinous with overall survival rates of 75–90%. Since then, it has been recognized that the two categories are heterogonous. There are now many different groups following the recognition of serous tumors with microinvasion, non‐invasive and invasive peritoneal implants and a micropapillary pattern, and of mucinous tumors with microinvasion, intraepithelial carcinoma and pseudomyxoma peritoneal implants, in addition to further delineation of endometrial, clear cell and transitional cell tumors with atypical proliferation. This review outlines the most recent information regarding the epidemiology, pathology and clinical management of borderline tumors. Surgical management to excise all visible tumors remains the cornerstone of therapy. Because borderline ovarian tumors often occur in reproductive‐age women, fertility is an important issue. Conservative surgery is a safe in carefully selected patients. Effective non‐surgical therapies are yet to be identified.
Are the GFRUP’s recommendations for withholding or withdrawing treatments in critically ill children applicable? Results of a two-year survey
Authors: Cremer R , Binoche A , Noizet O , Fourier C , Leteurtre S , Moutel G , Leclerc F
Published: February 2007

Objective:To evaluate feasibility of the guidelines of the Groupe Francophone de Réanimation et Urgence Pédiatriques (French-speaking group of paediatric intensive and emergency care; GFRUP) for limitation of treatments in the paediatric intensive care unit (PICU).

Design:A 2-year prospective survey.

Setting:A 12-bed PICU at the Hôpital Jeanne de Flandre, Lille, France.

Patients:Were included when limitation of treatments was expected.

Results:Of 967 children admitted, 55 were included with a 2-day median delay. They were younger than others (24v60 months), had a higher paediatric risk of mortality (PRISM) score (14v4), and a higher paediatric overall performance category (POPC) score at admission (2v1); all p<0.002. 34 (50% of total deaths) children died. A limitation decision was made without meeting for 7 children who died: 6 received do-not-resuscitate orders (DNROs) and 1 received withholding decision. Decision-making meetings were organised for 31 children, and the following decisions were made: 12 DNROs (6 deaths and 6 survivals), 4 withholding (1 death and 3 survivals), with 14 withdrawing (14 deaths) and 1 continuing treatment (survival). After limitation, 21 (31% of total deaths) children died and 10 survived (POPC score 4). 13 procedures were interrupted because of death and 11 because of clinical improvement (POPC score 4). Parents’ opinions were obtained after 4 family conferences (for a total of 110 min), 3 days after inclusion. The first meeting was planned for 6 days after inclusion and held on the 7th day after inclusion; 80% of parents were immediately informed of the decision, which was implemented after half a day.

Conclusions:GFRUPs procedure was applicable in most cases. The main difficulties were anticipating the correct date for the meeting and involving nurses in the procedure. Children for whom the procedure was interrupted because of clinical improvement and who survived in poor condition without a formal decision pointed out the need for medical criteria for questioning, which should systematically lead to a formal decision-making process.
Contesting the science/ethics distinction in the review of clinical research
Authors: Dawson Angus J , Yentis Steve M
Published: February 2007

Recent policy in relation to clinical research proposals in the UK has distinguished between two types of review: scientific and ethical. This distinction has been formally enshrined in the recent changes to research ethics committee (REC) structure and operating procedures, introduced as the UK response to the EU Directive on clinical trials. Recent reviews and recommendations have confirmed the place of the distinction and the separate review processes. However, serious reservations can be mounted about the science/ethics distinction and the policy of separate review that has been built upon it. We argue here that, first, the science/ethics distinction is incoherent, and, second, that RECs should not onlybe permittedto consider a study’s science, but that theyhave anobligationdo so.
OPTIMIZING LOCATION AMONG N-COUNTRIES UNDER EXCHANGE RATE UNCERTAINTY: APPLYING REAL OPTIONS
Authors: WU CHENG-RU , LIN CHIN-TSAI
Published: February 2007

This study considers the effects of one real exchange rate on strategies that govern locations of production by firms that are entering N - 1 foreign countries. The batch process production model (Lin, CT and CR Wu (2004a). Asia Pacific Journal of Operational Research, 21, 35–52) which considers two locations of production, one in each of two countries is extended to develop a decision valuation model to choose the two optimal locations to produce a good — one in each country. This extended model applies the real options approach (ROA) to determine the value of locating production in N countries. Moreover, a closed-form solution to the Continuous-Time Model Optimization Problem is derived. The optimal entry threshold value of a firm from country-0 to country-(N - 1) is calculated; a sensitivity analysis is performed, and some characteristic strategies of the operating method for the Constant Elasticity of Substitution (CES) batch process model among N countries are determined. Next, we can get optimal entry threshold value for Cobb-Douglas, perfect substitution and Leontief by CES production function. A useful summary of insights is provided for global managers.
AN EOQ MODEL WITH GENERALIZED RAMP-TYPE DEMAND AND WEIBULL DISTRIBUTION DETERIORATION
Authors: PANDA S. , SAHA S. , BASU M.
Published: February 2007

An inventory model is discussed with generalized ramp-type demand where the time to deterioration follows Weibull distribution. Shortages of inventories are allowed and completely backlogged. Total cost is derived by trading off setup cost, holding cost, deterioration cost, and shortage cost. The optimal replenishment policy for a single period is derived by minimizing the total cost per unit time over infinite time horizon. A numerical example is presented and sensitivity analysis is also carried out. The rationale for generalized ramp-type demand is discussed.