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Selected AbstractsModelling the hysteresis in the velocity pattern of slow-moving earth flows: the role of excess pore pressureEARTH SURFACE PROCESSES AND LANDFORMS, Issue 4 2005T. W. J. van Asch Abstract This paper describes the velocity pattern of a slow-moving earth flow containing a viscous shear band and a more or less rigid landslide body on top. In the case of small groundwater fluctuations, Bingham's law may describe the velocity of these slow-moving landslides, with velocity as a linear function of excess shear stress. Many authors have stated that in most cases a non-linear version of Bingham's law best describes the moving pattern of these earth flows. However, such an exponential relationship fails to describe the hysteresis loop of the velocity, which was found by some authors. These authors showed that the velocity of the investigated earth flows proved to be higher during the rising limb of the groundwater than during the falling limb. To explain the hysteris loop in the velocity pattern, this paper considers the role of excess pore pressure in the rheological behaviour of earth flows by means of a mechanistic model. It describes changes in lateral internal stresses due to a change in the velocity of the earth flow, which generates excess pore pressure followed by pore pressure dissipation. Model results are compared with a hysteresis in the velocity pattern, which was measured on the Valette landslide complex (French Alps). Copyright © 2005 John Wiley & Sons, Ltd. [source] Trade Balance and Exchange Rate: Unit Roots, Co-integration and Long Memory in the US and the UKECONOMIC NOTES, Issue 1 2008Luis A. Gil-Alana This paper deals with the relationship between the balance of trade and the exchange rate in the US/UK case. Many authors have studied this issue for many countries, but despite the intensive research, there is still no agreement about the effectiveness of currency devaluation to increase a country's balance of trade. We first analyse the relationship between the two variables using unit roots and co-integration methods, and the results are ambiguous. We try a new approach based on fractional integration. The unit root hypothesis is rejected in case of the trade balance in favour of smaller orders of integration, while this hypothesis is not rejected for the exchange rate. Thus, the two series do not possess the same order of integration. We sort this problem out by taking the exchange rate as an exogenous variable, and including it in a regression model where the residuals might follow a fractionally integrated model. [source] Biological and ecological traits of benthic freshwater macroinvertebrates: relationships and definition of groups with similar traitsFRESHWATER BIOLOGY, Issue 2 2000Philippe Usseglio-Polatera Summary 1Relating species traits to habitat characteristics can provide important insights into the structure and functioning of stream communities. However, trade-offs among species traits make it difficult to predict accurately the functional diversity of freshwater communities. Many authors have pointed to the value of working with groups of organisms as similar as possible in terms of relationships among traits and have called for definition of groups of organisms with similar suites of attributes. 2We used multivariate analyses to examine separately the relationships among 11 biological traits and among 11 ecological traits of 472 benthic macroinvertebrate taxa (mainly genera). The main objective was to demonstrate (1) potential trade-offs among traits; (2) the importance of the different traits to separate systematic units or functional groupings; and (3) uniform functional groups of taxa that should allow a more effective use of macroinvertebrate biological and ecological traits. 3We defined eight groups and 15 subgroups according to a biological trait ordination which highlighted size (large to small), reproductive traits (K to r strategists), food (animal to plant material) and feeding habits (predator to scraper and/or deposit feeder) as ,significant' factors determining the ordination of taxa. This ordination partly preserved phylogenetic relationships among groups. 4Seven ecological groups and 13 ecological subgroups included organisms with combinations of traits which should be successively more adequate in habitats from the main channel to temporary waters, and from the crenon to the potamic sections of rivers, and to systems situated outside the river floodplain. These gradients corresponded to a gradual shift from (1) rheophilic organisms that lived in the main channel of cold oligotrophic mountain streams to (2) animals that preferred eutrophic habitats of still or temporary waters in lowlands. The groups with similar ecological traits had a more diverse systematic structure than those with similar biological traits. 5Monitoring and assessment tools for the management of water resources are generally more effective if they are based on a clear understanding of the mechanisms that lead to the presence or absence of species groups in the environment. We believe that groups with similar relationships among their species traits may be useful in developing tools that measure the functional diversity of communities. [source] THE USES OF WALTER: WALTER BENJAMIN AND THE COUNTERFACTUAL IMAGINATIONHISTORY AND THEORY, Issue 3 2010BENJAMIN ALDES WURGAFT ABSTRACT Many authors, both scholarly and otherwise, have asked what might have happened had Walter Benjamin survived his 1940 attempt to escape Nazi-occupied Europe. This essay examines several implicitly or explicitly "counterfactual" thought experiments regarding Benjamin's "survival," including Hannah Arendt's influential "Walter Benjamin: 1892,1940," and asks why our attachment to Benjamin's story has prompted so much counterfactual inquiry. It also explores the larger question of why few intellectual historians ask explicitly counterfactual questions in their work. While counterfactuals have proven invaluable for scholars in diplomatic, military, and economic history, those writing about the history of ideas often seem less concerned with chains of events and contingency than some of their colleagues are,or they attend to contingency in a selective fashion. Thus this essay attends to the ambivalence about the category of contingency that runs through much work in intellectual history. Returning to the case of Walter Benjamin, this essay explores his own tendency to pose "what if?" questions, and then concludes with an attempt to ask a serious counterfactual question about his story. The effort to ask this question reveals one methodological advantage of counterfactual inquiry: the effort to ask such questions often serves as an excellent guide to the prejudices and interests of the historian asking them. By engaging in counterfactual thought experiments, intellectual historians could restore an awareness of sheer contingency to the stories we tell about the major texts and debates of intellectual history. [source] Caring in nursing: a different interpretationJOURNAL OF ADVANCED NURSING, Issue 6 2001Jane Sumner PhD MN RNC Caring in nursing: a different interpretation Aim.,To apply Habermas' (1995) Theory of Moral Consciousness and Communicative Action to the nurse,patient relationship, offering a different interpretation to the nurse,patient relationship that is caring in nursing. Rationale.,Many authors have described the nurse,patient relationship, but Habermas' theory synthesizes the components into a complex matrix that is caring in nursing. Findings.,The theory offers three claims to normative validity: the claim to truth which is the factual objective knowledge; the claim to truthfulness which refers to the intrasubjective self; and the claim to right which is the intersubjective interaction. The validity claims explain the patient's personal and illness self, the nurse's personal and professional self, and the interaction/discourse. The interaction is situation specific, and is identified as moral because dialogue/discourse requires a ,considerateness' of each for the other. ,Considerateness' in discourse requires certain rules, including that each participant has an equal voice, be followed in order for the Principle of Universalization to occur. Habermas draws on Kohlberg's (1981), and Selman's (1980) work to develop three levels of moral maturity of communication. These are preconventional, conventional, and postconventional. Initial moral maturity is egocentric, subjective, and obedient to authority. Maturity develops with recognition of other and reciprocity. At the postconventional level there is mutuality and the ability for abstract reasoning. There is a third person objectivity combining speaker and addressee/listener perspectives. Norms are not just accepted, they are reasoned through. This leads to justification of the norm, which is then accepted as valid. When the three validity claims are met and there is genuine ,considerateness' in the interaction there is communicative action. The reverse is strategic action, where the communication is coercive. When there is communicative action both patient and nurse are validated with a sense of fulfillment or On Some Recent Claims for the Efficacy of Cognitive Therapy for People with Intellectual DisabilitiesJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 1 2006Peter Sturmey Background, Many authors have expressed concern regarding the efficacy of psychotherapy, including psychotherapy for people with intellectual disabilities. Materials and Methods, Recently, many authors have made claims for the effectiveness of cognitive therapy for treating people with intellectual disabilities. During this debate, applied behaviour analysis has been misrepresented by incorrectly labelling behavioural as cognitive techniques, repeated misrepresentations of behaviourism and attributing the efficacy of treatment packages to cognitive components of undemonstrated efficacy when it is more parsimonious to attribute efficacy to behavioural elements of known efficacy. Conclusions, This article documents and corrects these errors. [source] The virtue and vice of workplace conflict: food for (pessimistic) thoughtJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 1 2008Carsten K.W. De Dreu Many authors, myself included, have suggested that workplace conflict may be beneficial to the organization. I argue that the support for this conclusion is rather weak. A selective and necessarily limited review of the literature shows that: (1) the positive functions of conflict are found only under an exceedingly narrow set of circumstances, (2) the conclusion that (particular forms of) conflict and conflict management has positive functions can be criticized on methodological grounds, (3) even under favorable circumstances a number of serious negative functions can be identified as well, (4) negative functions easily outweigh positive functions, prohibiting the emergence of ,positive workplace conflict' (where conflict has predominantly positive consequences), and (5) organizations need cooperative conflict management not because it brings positive conflict, but because it prevents workplace conflict to hurt too much. Copyright © 2007 John Wiley & Sons, Ltd. [source] The Impact of Human Recreational Activities in Marine Protected Areas: What Lessons Should Be Learnt in the Mediterranean Sea?MARINE ECOLOGY, Issue 2002Marco Milazzo Abstract. The aesthetic appeal of marine reserves and the facilities provided, together with the increased public awareness of nature, all contribute to creating massive tourism in MPAs. Human activities are being changed inside MPAs in two ways: humans as top predators are generally being removed, but in turn they could come back at great numbers as visitors. Many authors have studied the impact of visitors, and the results highlight that the consequences can be very substantial and may represent a severe threat to the overall diversity of marine communities. To date, the documented effects of human recreational activities on natural communities are restricted to assessing the consequences of trampling over intertidal and upper infralittoral areas, boat anchoring in seagrass meadows and tropical reefs, or SCUB A-diving. In this paper we review the available literature world-wide on the effects of human recreational activities in marine communities. The objective is to address the extent of these impacts and to highlight the gaps of knowledge to be filled in order to optimise decision making on research, monitoring, and management of Mediterranean MPAs. A specific plan for managing tourism use in each Mediterranean MPA should be designated. These strategies should be implemented through education, training, and changes in legislation and policy. [source] Correlation between the dioptric power, astigmatism and surface shape of the anterior and posterior corneal surfacesOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2009David Mas Abstract A knowledge of the shape of the cornea is of major importance for the planning and monitoring of surgery, and for the correct diagnosis of corneal diseases. Many authors have studied the geometry of the second corneal surface in the central region and it has been stated that there is a high correlation between the central radii of curvature and asphericities of the two corneal surfaces. In this work we extend this study to a larger, central, 6 mm diameter of the cornea. Surface height data, obtained with an Oculus Pentacam from 42 eyes of 21 subjects, were analysed to yield surface power vectors. Corneal heights of both surfaces were also decomposed into low-order Zernike polynomials and the correlations between each of the power vectors and low-order Zernike coefficients for the two surfaces were studied. There was not only a strong correlation between spherical powers and Zernike defocus coefficients, but also between the astigmatic components. The correspondence between the astigmatism in both surfaces found here can be of the utmost importance in planning optical surgery, since perfect spherical ablation of the first surface does not assure total correction of corneal astigmatism. [source] Knowledge and Subjunctive ConditionalsPHILOSOPHY COMPASS (ELECTRONIC), Issue 6 2007Juan Comesaña What relation must hold between a fact p and the corresponding belief that p for the belief to amount to knowledge? Many authors have recently proposed that the relation can be captured by subjunctive conditionals. In this paper I critically evaluate the main proposals along those lines. [source] Do Tax-Deferred Exchanges Impact Purchase Price?REAL ESTATE ECONOMICS, Issue 4 2001Evidence from the Phoenix Apartment Market Many authors have commented on the compliance risk associated with tax-deferred exchanges. However, no published studies explicitly address whether the risks associated with the exchange process impact the price at which exchanged assets trade. Using a unique data set that documents transactions for nondirect exchanges, this study examines the price impact of tax-deferred exchanges on apartment transactions in the Phoenix, Arizona, market. Consistent with the price pressure hypothesis originally developed by Scholes (1972) and Kraus and Stoll (1972) and the tax capitalization hypothesis proposed by Oates (1969), the data show that exchange participants pay an economically significant premium to acquire replacement assets. A conventional hedonic price index is generated to investigate the rational bounds of the exchange premium. [source] Teaching & Learning Guide for: Can a Darwinian Be a Christian?RELIGION COMPASS (ELECTRONIC), Issue 3 2008Gregory W. Dawes Author's Introduction The article was provoked by recent discussion of the so-called ,conflict thesis': the idea that the Christian faith and the findings of modern science are necessarily at odds. This thesis is generally attributed to John William Draper (1811,1882) and Andrew Dickson White (1832,1918). Recent opposition to their work dates from a 1979 publication by James Moore. Moore argues that the warfare metaphor employed by Draper and White misrepresents the historical reality, by suggesting that the religion and science debates were clashes between distinct groups of people who were sharply polarized and violently antagonistic. Since then, similar criticisms have been made by historians, such as David Livingstone, Ronald Numbers, and David Lindberg. A key question here is: what does the conflict thesis entail? If it holds that Christian thinkers have invariably opposed scientific progress, while the defenders of science have been non-believers, it would be demonstrably false. But there exist more interesting forms of conflict thesis, which are philosophical rather than historical. These suggest that there is some tension between what Christians have traditionally believed and the findings of modern science, particularly Darwin's theory of evolution by natural selection. Even if the two are not, strictly speaking, incompatible, the truth of one may constitute evidence against the truth of the other. Darwin's theory also undercuts traditional arguments from design, and highlights the epistemological divide between religious and scientific conceptions of authority. Online Materials The following sites contain audio and video files, as well as text and images. 1. http://www.meta-library.net/history/intro-frame.html This is a useful overview of the historical debate by Ronald Numbers, with links to other sites. Most presenters follow Moore in opposing the conflict thesis, narrowly defined, but neglect the conflicts that my article highlights. 2. http://www.pbs.org/wgbh/nova/id/program.html Here one can view an excellent, 2-h PBS television documentary on the Dover, Pennsylvania trial in December 2005 regarding the teaching of ,intelligent design' (ID) in public schools. 3. http://www.butler.edu/clergyproject/rel_evol_sun.htm This is a letter signed by more than 11,000 clergy, arguing that there is no conflict between religion and science, and encouraging (among other things) the liturgical celebration of evolution by natural selection. 4. http://www.discovery.org/csc/ At the other end of the theological spectrum, this is the website of the Discovery Institute, devoted to opposing Darwinism and promoting ,intelligent design' (ID). Controversially, it presents ID as a scientific theory, rather than a religious doctrine. 5. http://www.asa3.org/ Somewhere between the Clergy Letter Project and the Discovery Institute lies the American Scientific Affiliation (ASA). The ASA ,does not take a position when there is honest disagreement between Christians', so it embraces a variety of perspectives. Sample Syllabus The following could form the basis for a graduate seminar on religion and science, focusing on the Darwinian controversies. One could, for instance, devote two classes to each of these topics. 1. The Draper-White Thesis I recommend reading extracts from the two writers thought to be responsible for the conflict thesis, to establish what each actually said. John William Draper, The History of the Conflict between Religion and Science, International Scientific Series 13 (London: Henry S. King & Co., 1875), chap. 8. Andrew Dickson White, A History of the Warfare of Science with Theology in Christendom (1896; New York, NY: Dover Publications, 1960), vol. 1, chap. 1. 2. Criticism of the Draper-White Thesis Either of the following readings from historians critical of Draper and White's work would be a useful starting point for discussion. James R. Moore, The Post-Darwinian Controversies: A Study of the Protestant Struggle to Come to Terms with Darwin in Great Britain and America, 1870,1900 (Cambridge: Cambridge University Press, 1979), chap. 1. David N. Livingstone, ,Re-placing Darwinism and Christianity', in David C. Lindberg and Ronald L. Numbers (eds.), When Science and Christianity Meet, pp. 183,202 (Chicago, IL: University of Chicago Press, 2003). 3. The Incompatibility Thesis Many authors attempt to show that Darwinism and Christianity and compatible. But it would be useful to examine Pope John Paul II's statement on this topic, along with some responses by biologists and philosophers. John Paul II, ,The Pope's Message on Evolution and Four Commentaries', The Quarterly Review of Biology, 72:4 (1997): 375,406. 4. The Evidential Thesis Students might enjoy reading and discussing the following article by a leading evolutionary biologist. George C. Williams, ,Mother Nature Is a Wicked Old Witch', in Matthew H. Nitecki and Doris V. Nitecki (eds.), Evolutionary Ethics, 217,31 (Albany, NY: State University of New York Press, 1993). 5. The Replacement Thesis This is an important but often neglected book. Students would benefit from reading at least the first chapter. Neal C. Gillespie, Charles Darwin and the Problem of Creation (Chicago, IL: University of Chicago Press, 1979), chap. 1. 6. The Faith and Reason Thesis The following article by a well-known historian and philosopher of science touches on some of the key issues. Ernan McMullin, ,Evolution and Special Creation', Zygon 28:3 (1993): 299,335. Focus Questions 1There exist many Christian thinkers who accept Darwin's theory of evolution by natural selection. Does that mean there is no conflict between Darwinism and Christianity? 2Taken at face value, Genesis 1,3 tells the story of the origins of the world and of human beings. What aspects of that story would you consider essential to the Christian faith? 3If we have an entirely natural explanation of the origins of complex living organisms, do we still have reasons to believe in a creator God? 4If God could have created complex living beings by a simple command, why would he choose a lengthy and wasteful process such as natural selection? 5Could a Christian regard the existence of God in the same way as a scientific hypothesis, that is to say, to be accepted only in so far as it is supported by the evidence? Seminar Activity I would suggest a debate, in which students sympathetic to the creationist position are asked to defend Darwin's theory, while students sympathetic to evolution are asked to argue against it. [source] Body condition does not predict immunocompetence of western pond turtles in altered versus natural habitatsANIMAL CONSERVATION, Issue 3 2010N. Polo-Cavia Abstract Many authors have addressed the relationship between body condition and ecological parameters in a wide range of studies, suggesting a better fitness in those individuals with higher values of body condition. However, body size and body condition of individuals can vary significantly at the intraspecific level between geographic locations, which is usually explained by phenotypic plasticity or local adaptation. We suggest that a higher body condition per se might not be a good indicator of physiological health status, particularly when comparing populations inhabiting places with different levels of habitat alteration. We examined two populations of the western pond turtle Emys marmorata in the northern part of California's Central Valley, and found that individuals inhabiting a water pollution control plant located on the valley floor had significantly larger body size and higher body condition than those inhabiting an unaltered natural habitat in the foothills. However, turtles from the water pollution control plant did not show a better health status, estimated by comparisons between two immune system variables: T-cell-mediated immune response and heterophil/lymphocyte ratio. Parameters such as body size and body condition might be misleading indicators of health condition, particularly when they are used to estimate health status of populations from habitats with different levels of alteration. We emphasize the importance of using physiological methods in assessing the conservation state of wildlife populations, rather than relying on biometric indices that might miss important effects of alteration. [source] CLAY RESOURCES AND TECHNICAL CHOICES FOR NEOLITHIC POTTERY (CHALAIN, JURA, FRANCE): CHEMICAL, MINERALOGICAL AND GRAIN-SIZE ANALYSES*ARCHAEOMETRY, Issue 1 2007R. MARTINEAU Many authors have considered pottery manufacturing constraints and sociocultural elements as factors in change in past civilizations over time. The main issue of this research is to better understand the reasons for changes, or choices, in pottery raw materials. The very precise and detailed stratigraphy and cultural succession of occupations is based on dendrochronological data from the lake-dwelling sites of Chalain (Jura, France). Petrographic, palaeontological and chemical analyses were used to determine the nature and origins of the raw materials used by the Neolithic potters. Stratigraphy and dendrochronological data were used to reconstruct in detail the evolution dynamics of fabric changes. Several raw material sources were identified for many of the pottery groups. Each of them was sampled for qualitative experimental tests of pottery forming. The experimental results show a high variability between the sediments tested. This variability was quantitatively estimated by XRF, XRD, the Rietveld method, calcium carbonate quantification and laser grain-size analyses of matrices, indirect measures of plasticity. These analytical results allow a better understanding of the differences observed in the experimental tests. On the basis of these experimental and analytical results, changing parameters such as pottery manufacturing constraints, mineralogical characteristics of raw materials and sociocultural factors are considered. In conclusion, all the social and technical parameters, in each archaeological context, must be taken into account for a better understanding of the changes occurring throughout the chronological sequence. [source] An In Vitro Study Of Coronal Microleakage In Endodontically-Treated Teeth Restored With PostsAUSTRALIAN ENDODONTIC JOURNAL, Issue 3 2003Shohreh Ravanshad DMD. Coronal microleakage has received considerable attention as a factor related to failure of endodontic treatment and much emphasis is placed on the quality of the final restoration. Posts are frequently used for the retention of coronal restorations. These can be custom-made or prefabricated. Many authors have examined coronal microleakage with respect to gutta-percha root fillings and plastic coronal restorations, but few have investigated the coronal seal afforded by various post systems. The seal provided by a cemented post depends on the seal of the cement used. The purpose of this study was to compare coronal microleakage around cast and prefabricated posts using a dye-penetration method. Sixty extracted single-rooted human teeth were chemomechanically prepared. The root canals were filled with gutta-percha and sealer and they were then prepared for standard posts. Six groups, each of 10 teeth, were restored with either cast post or prefrabricated post. The posts were cemented with either glass ionomer cement (GIC), Variolink II or Durelon. The teeth were thermocycled and placed in Indian ink for one week. They were then demineralised and rendered transparent. Linear coronal dye penetration around the post was measured and compared. The least dye-penetration was observed in roots restored with a cast post and Variolink II. Dentatus posts demonstrated the most microleakage. It appears that the dentine-bonding cements have less microleakage than the traditional, non-dentine-bonding cements and adaptation of the post with the canal may be more important than the cement used. [source] Influence of 1 and 25 Hz, 1.5 mT magnetic fields on antitumor drug potency in a human adenocarcinoma cell line,BIOELECTROMAGNETICS, Issue 8 2002M.J. Ruiz-Gómez Abstract The resistance of tumor cells to antineoplastic agents is a major obstacle during cancer chemotherapy. Many authors have observed that some exposure protocols to pulsed electromagnetic fields (PEMF) can alter the efficacy of anticancer drugs; nevertheless, the observations are not clear. We have evaluated whether a group of PEMF pulses (1.5 mT peak, repeated at 1 and 25 Hz) produces alterations of drug potency on a multidrug resistant human colon adenocarcinoma (HCA) cell line, HCA-2/1cch. The experiments were performed including (a) exposures to drug and PEMF exposure for 1 h at the same time, (b) drug exposure for 1 h, and then exposure to PEMF for the next 2 days (2 h/day). Drugs used were vincristine (VCR), mitomycin C (MMC), and cisplatin. Cell viability was measured by the neutral red stain cytotoxicity test. The results obtained were: (a) The 1 Hz PEMF increased VCR cytotoxicity (P,<,0.01), exhibiting 6.1% of survival at 47.5 ,g/ml, the highest dose for which sham exposed groups showed a 19.8% of survival. For MMC at 47.5 ,g/ml, the % of survival changed significantly from 19.2% in sham exposed groups to 5.3% using 25 Hz (P,<,0.001). Cisplatin showed a significant reduction in the % of survival (44.2,39.1%, P,<,0.05) at 25 Hz and 47.5 ,g/ml, and (b) Minor significant alterations were observed after nonsimultaneous exposure of cells to PEMF and drug. The data indicate that PEMF can induce modulation of cytostatic agents in HCA-2/1cch, with an increased effect when PEMF was applied at the same time as the drug. The type of drug, dose, frequency, and duration of PEMF exposure could influence this modulation. Bioelectromagnetics 23:578,585, 2002. © 2002 Wiley-Liss, Inc. [source] Detection of myxovirus resistance protein A in lichen planus lesions and its relationship to hepatitis C virusBRITISH JOURNAL OF DERMATOLOGY, Issue 5 2009O.G. Shaker Summary Background, Lichen planus (LP) is an inflammatory disease of the skin and oral mucosa. Studies suggested that type I interferons (IFNs) could play an important role in the cytotoxic inflammation in LP. Type I IFNs stimulate the production of several IFN-induced proteins including myxovirus resistance protein A (MxA protein). The association of LP and chronic hepatitis C is well established, with variable prevalence rates among different populations. Many authors have considered hepatitis C virus (HCV) as a possible antigen for inducing cytotoxic immune response in LP. Objectives, To investigate the role of type I IFNs in LP through the detection of MxA protein, and to compare the expression of MxA protein between HCV-positive and HCV-negative patients with LP in an attempt to clarify the role of HCV in the pathogenesis of LP. Methods, The study included 33 skin biopsies from patients with LP and 10 control biopsies. MxA mRNA was detected by reverse transcription-polymerase chain reaction. HCV-specific antibodies were detected in patient sera by enzyme-linked immunosorbent assay. Results, Our analysis revealed a significantly higher level of MxA protein in all the LP skin biopsies compared with controls. The expression was significantly higher in HCV-positive patients than in HCV-negative patients. Conclusions, Type I IFNs play a role in the pathogenesis of LP, and HCV could induce LP through increasing the production of type I IFNs. [source] Hospital volume influences the choice of operation for thyroid cancerBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 11 2009J. C. Lifante Background: Many authors advocate total or near-total thyroidectomy for thyroid carcinoma. This study examined the relationship between hospital volume of thyroidectomies and choice of bilateral thyroidectomy for thyroid carcinoma. Methods: Data were extracted from the administrative databases of all hospital discharge abstracts in the Rhône-Alpes area of France. The study population included inpatient stays from 1999 to 2004 with a diagnosis of thyroid disease (benign or malignant) and a procedural code for thyroid surgery. Multivariable logistic regression analyses were performed to determine factors associated with the extent of surgery (unilateral versus bilateral) for thyroid carcinoma. Results: A total of 20 140 thyroidectomies were identified, including 4006 procedures for cancer. Compared with hospitals performing a high volume of procedures for all thyroid diseases (at least 100 annually), the risk of a unilateral procedure for thyroid cancer increased by 2·46 (95 per cent confidence interval 1·63 to 3·71) in low-volume hospitals (fewer than ten operations per year) and by 1·56 (1·27 to 1·92) in medium-volume centres (ten to 99 per year). Conclusion: There is a significant relationship between hospital volume and the decision to perform bilateral surgery for thyroid carcinoma. Thyroid cancer surgery should be performed by experienced surgical teams in high-volume centres. Copyright © 2009 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Parsimony overcomes statistical inconsistency with the addition of more data from the same geneCLADISTICS, Issue 5 2005Kurt M. Pickett Many authors have demonstrated that the parsimony method of phylogenetic analysis can fail to estimate phylogeny accurately under certain conditions when data follow a model that stipulates homogeneity of the evolutionary process. These demonstrations further show that no matter how much data are added, parsimony will forever exhibit this statistical inconsistency if the additional data have the same distributional properties as the original data. This final component,that the additional data must follow the same distribution as the original data,is crucial to the demonstration. Recent simulations show, however, that if data evolve heterogeneously, parsimony can perform consistently. Here we show, using natural data, that parsimony can overcome inconsistency if new data from the same gene are added to an analysis already exhibiting a condition indistinguishable from inconsistency. © The Willi Hennig Society 2005. [source] Creative Leaders: A Decade of Contributions from Creativity and Innovation Management JournalCREATIVITY AND INNOVATION MANAGEMENT, Issue 1 2006Tudor Rickards The study reveals nine overlapping themes, within each of which leadership plays a part in the production of creative insights or innovative productivity. However, for many authors, leadership remains an implicit factor within their models of change. We suggest that leadership, creativity and innovation are knowledge systems which can be more closely integrated for improved theory and practice within communities of practice. [source] The appropriate use of references in a scientific research paperEMERGENCY MEDICINE AUSTRALASIA, Issue 2 2002David McD Taylor Abstract References have an important and varied role in any scientific paper. Unfortunately, many authors do not appreciate this importance and errors within reference lists are frequently encountered. Most reference errors involve spelling, numerical and punctuation mistakes, although the use of too many, too few or even inappropriate references is often seen. The consequences of reference errors include difficulty in reference retrieval, limitation for the reader to read more widely, failure to credit the cited authors, and inaccuracies in citation indexes. This paper discusses the value of accurate reference lists and provides guidelines for their preparation. [source] Ribonucleases expressed by human pancreatic adenocarcinoma cell linesFEBS JOURNAL, Issue 5 2000Ester Fernández-Salas Human ribonucleases have been considered as a possible tumor marker for pancreatic cancer, and elevated serum levels of ribonuclease activity in patients with pancreatic cancer have been reported by many authors. The reason for this elevation is unknown. In this study, we demonstrate that human pancreatic adenocarcinoma cell lines synthesize and secrete different ribonucleases. We isolated and characterized human pancreatic, or secretory, ribonuclease (RNase 1) from the conditioned media of the human pancreatic adenocarcinoma cell lines Capan-1, MDAPanc-3, IBF-CP3 and Panc-1, and the ampullary adenocarcinoma cell line MDAAmp-7, which represent a wide range of differentiation stages. Only one of these cell lines, Panc-1, produces significant amounts of nonsecretory ribonuclease. We then established a purification procedure for both secretory and nonsecretory ribonucleases, consisting of concentration of the supernatant by tangential filtration, anion-exchange and cation-exchange liquid chromatography and C4 RP-HPLC. Ribonuclease activity fractions were monitored using both the spectrophotometric and negative-staining zymogram techniques. The results of N-terminal sequence analysis, kinetic analysis and endoglycosidase digestion studies indicate that the main ribonuclease secreted by all the cell lines is the secretory-type ribonuclease and that it is composed of several differently N -glycosylated forms. Northern blot analyses confirm that some of the cell lines express secretory ribonuclease mRNA. The mRNA levels produced by Panc-1 and MDAPanc-28 are too low to be detected. Similar levels of expression of nonsecretory ribonuclease are found by Northern blot analysis in all the cell lines except Panc-1, which expresses higher levels. Here, we describe, for the first time, that several human pancreatic cancer cell lines with different degrees of differentiation express and secrete ribonucleases. This fact indicates that one origin of the elevated serum RNase levels in patients with pancreatic cancer are tumor cells. Analysis of the oligosaccharide moiety of the RNase 1 secreted by Capan-1 shows that it is highly glycosylated and its N -glycan chains are significantly different from that of the RNase 1 produced by normal pancreas. These results renew the possibility of using human serum RNase 1 determination as a tumor marker. [source] Characterizing regime shifts in the marine environmentFISH AND FISHERIES, Issue 2 2006Kathryn Lees Abstract Recent years have seen a plethora of studies reporting that ,regime shifts' have occurred in the North Atlantic and Pacific Oceans during the last century. In many cases, the criteria used to distinguish a regime shift have not been explicitly stated. In other cases, a formal definition has been proposed and the data set assessed against it. Developing a universal quantitative definition for identifying and distinguishing between purported climatic and ecological regime shifts has proved problematic as many authors have developed criteria that seem unique to the system under study. Consequently, they throw little light on the drivers of ecological regime shifts. Criteria used to define regime shifts are reviewed and on the basis of evidence from purported regime shifts, common characteristics in the speed and amplitude of the changes and the duration of quasi-stable states are used to propose a more clearly defined set of criteria for defining climatic and ecological regime shifts. Causal drivers of regime shifts are explored using correlation analysis. Limitations of these methods are discussed. [source] Optimal clinical trial design using value of information methods with imperfect implementationHEALTH ECONOMICS, Issue 5 2010Andrew R. Willan Abstract Traditional sample size calculations for randomized clinical trials are based on the tests of hypotheses and depend on somewhat arbitrarily chosen factors, such as type I and II errors rates and the smallest clinically important difference. In response to this, many authors have proposed the use of methods based on the value of information as an alternative. Previous attempts have assumed perfect implementation, i.e. if current evidence favors the new intervention and no new information is sought or expected, all future patients will receive it. A framework is proposed to allow for this assumption to be relaxed. The profound effect that this can have on the optimal sample size and expected net gain is illustrated on two recent examples. In addition, a model for assessing the value of implementation strategies is proposed and illustrated. Copyright © 2009 John Wiley & Sons, Ltd. [source] From mixed finite elements to finite volumes for elliptic PDEs in two and three dimensionsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 3 2004Anis Younes Abstract The link between Mixed Finite Element (MFE) and Finite Volume (FV) methods applied to elliptic partial differential equations has been investigated by many authors. Recently, a FV formulation of the mixed approach has been developed. This approach was restricted to 2D problems with a scalar for the parameter used to calculate fluxes from the state variable gradient. This new approach is extended to 2D problems with a full parameter tensor and to 3D problems. The objective of this new formulation is to reduce the total number of unknowns while keeping the same accuracy. This is achieved by defining one new variable per element. For the 2D case with full parameter tensor, this new formulation exists for any kind of triangulation. It allows the reduction of the number of unknowns to the number of elements instead of the number of edges. No additional assumptions are required concerning the averaging of the parameter in hetero- geneous domains. For 3D problems, we demonstrate that the new formulation cannot exist for a general 3D tetrahedral discretization, unlike in the 2D problem. However, it does exist when the tetrahedrons are regular, or deduced from rectangular parallelepipeds, and allows reduction of the number of unknowns. Numerical experiments and comparisons between both formulations in 2D show the efficiency of the new formulation. Copyright © 2003 John Wiley & Sons, Ltd. [source] Nurses' perceptions of care and caringINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 1 2002BA(Hons), Chris Bassett RN Care and caring have been identified as inherently difficult concepts to define, but many authors believe that care is the central and unifying core of nursing. It is vital that nurses understand what care is, with the current issues about measuring and justifying exactly what they do for patients in order to be clear about what good care is. If nurses are to constantly improve the care they give, they need to be clearer about how to care for patients. Nurses need to make sure that they are giving the patients what they want and not what the nurses want. This review of the literature explores nurses' perceptions of care and compares it with what patients want in terms of care. It also highlights some important and interesting differences between what patients and nurses perceive as good care. [source] An analysis of the dynamic , polarization in the V state of etheneINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 13 2010Celestino Angeli Abstract The importance of the dynamic , polarization (absent in methods where the , skeleton is treated at a mean-field level) for the correct description of the V state of the ethene molecule has been recognized by many authors in the past. In this article, this physical effect is analyzed and it is seen as arising from the sum of two contributions: the polarization of the , CC bond and of the , CH bonds. In both cases it is described in a valence bond scheme and the types of excitations needed in a molecular orbital frame to introduce such effects are identified. The effect of the dynamic , polarization on the spatial extent of the V state (,x2,) is described. The analysis here reported has been used in a recent article (Angeli, J Comp Chem 2009, 30, 1319) for the accurate calculation of the V state and of its vertical excitation energy. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem 110:2436,2447, 2010 [source] Tectonic accretion of a subducted intraoceanic remnant arc in Cretaceous Hokkaido, Japan, and implications for evolution of the Pacific northwestISLAND ARC, Issue 4 2005Hayato Ueda Abstract An accretionary complex, which contains fragments of a remnant island arc, was newly recognized in the Cretaceous accretionary terranes in Hokkaido, Japan. It consists of volcanics, volcanic conglomerate, intermediate to ultramafic intrusive rocks with island-arc affinity including boninitic rocks, accompanied by chert and deformed terrigenous turbidites. Compared with the results of modern oceanic surveys, the preserved sequence from island-arc volcanics to chert, via reworked volcanics, is indicative of intraoceanic remnant arc, because the sequence suggests an inactive arc isolated within a pelagic environment before its accretion. The age of a subducting oceanic crust can be discontinuous before and after a remnant-arc subduction, resulting in abrupt changes in accretion style and metamorphism, as seen in Cretaceous Hokkaido. Subduction of such an intraoceanic remnant arc suggests that the subducted oceanic plate in the Cretaceous was not an extensive oceanic plate like the Izanagi and/or Kula Plates as previously believed by many authors, but a marginal basin plate having an arc,back-arc system like the present-day Philippine Sea Plate. [source] On Some Recent Claims for the Efficacy of Cognitive Therapy for People with Intellectual DisabilitiesJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 1 2006Peter Sturmey Background, Many authors have expressed concern regarding the efficacy of psychotherapy, including psychotherapy for people with intellectual disabilities. Materials and Methods, Recently, many authors have made claims for the effectiveness of cognitive therapy for treating people with intellectual disabilities. During this debate, applied behaviour analysis has been misrepresented by incorrectly labelling behavioural as cognitive techniques, repeated misrepresentations of behaviourism and attributing the efficacy of treatment packages to cognitive components of undemonstrated efficacy when it is more parsimonious to attribute efficacy to behavioural elements of known efficacy. Conclusions, This article documents and corrects these errors. [source] A model for the species,area,habitat relationshipJOURNAL OF BIOGEOGRAPHY, Issue 1 2003K. A. Triantis Abstract Aim, To propose a model (the choros model) for species diversity, which embodies number of species, area and habitat diversity and mathematically unifies area per se and habitat hypotheses. Location, Species richness patterns from a broad scale of insular biotas, both from island and mainland ecosystems are analysed. Methods, Twenty-two different data sets from seventeen studies were examined in this work. The r2 values and the Akaike's Information Criterion (AIC) were used in order to compare the quality of fit of the choros model with the Arrhenius species,area model. The classic method of log-log transformation was applied. Results, In twenty of the twenty-two cases studied, the proposed model gave a better fit than the classic species,area model. The values of z parameter derived from choros model are generally lower than those derived from the classic species,area equation. Main conclusions, The choros model can express the effects of area and habitat diversity on species richness, unifying area per se and the habitat hypothesis, which as many authors have noticed are not mutually exclusive but mutually supplementary. The use of habitat diversity depends on the specific determination of the ,habitat' term, which has to be defined based on the natural history of the taxon studied. Although the values of the z parameter are reduced, they maintain their biological significance as described by many authors in the last decades. The proposed model can also be considered as a stepping-stone in our understanding of the small island effect. [source]
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