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Considerable Controversy (considerable + controversy)
Selected AbstractsRecharge Through a Regional Till Aquitard: Three-Dimensional Flow Model Water Balance ApproachGROUND WATER, Issue 3 2000Richard E. Gerber In southern Ontario, vertical leakage through a regionally extensive till is the primary source of recharge to underlying aquifers used for domestic and municipal water supply. Since leakage is largely controlled by the bulk hydraulic conductivity (K) of the aquitard, accurate estimates of K are necessary to quantify the resource. Considerable controversy exists regarding estimates of K for this aquitard, which vary according to the scale of the test method. For the till matrix, estimates from core samples and slug tests consistently range from 10,11 to 10,10 m/s. Isotopic evidence (3H), on the other hand, indicates that nonmatrix structures such as sand lenses, erosional surfaces, joints, and fractures significantly enhance till permeability. This is confirmed by slug test, pump test, recharge, and water balance studies, which show that K varies over seven orders of magnitude (10,12 to 10,5 m/s). To provide a regional estimate of bulk K and a reliable estimate of vertical recharge through the Northern Till, a numerical ground water flow model was constructed for the Duffins and Petticoat Creek drainage hasin. The model was calibrated to measurements of hydraulic head and estimates and measurements of base flow throughout the basin. This model demonstrates that the vertical hydraulic conductivity (Kv) for the Northern Till ranges from 5 × 10,10 to 5 × 10,9 m/s, values that are up to 2.5 orders of magnitude greater than matrix K estimates. Regional recharge through the Northern Till is estimated to range from 30 to 35 mm/a. [source] Accounting for the trend in trade union recognition in IrelandINDUSTRIAL RELATIONS JOURNAL, Issue 1 2001William K. Roche Considerable controversy surrounds the issue of union recognition in Irish industrial relations. Academic commentators have sought to identify and explain the trend in recognition since the 1980s. Their arguments are examined and tested. No secular rise in non-recognition is evident, and ,individualisation' and ,union substitution' are shown to add little to explaining the trend. No evidence is found that the trend reflects Irish employers pursuing union suppression and US-employers pursuing union substitution. The significant development is a sharp rise in non-recognition among new US employers. Their anti-union animus does not, however, appear to be coupled with any distinctive or generalised union avoidance strategy. [source] Minimum Bedrock Exposure Ages and Their Implications: Larsemann Hills and Neighboring Bolingen Islands, East AntarcticaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 3 2010Feixin HUANG Abstract: Considerable controversy exists over whether or not extensive glaciation occurred during the global Last Glacial Maximum (LGM) in the Larsemann Hills. In this study we use the in situ produced cosmogenic nuclide 10Be (half life 1.51 Ma) to provide minimum exposure ages for six bedrock samples and one erratic boulder in order to determine the last period of deglaciation in the Larsemann Hills and on the neighboring Bolingen Islands. Three bedrock samples taken from Friendship Mountain (the highest peak on the Mirror Peninsula, Larsemann Hills; ,2 km from the ice sheet) have minimum exposure ages ranging from 40.0 to 44.7 ka. The erratic boulder from Peak 106 (just at the edge of the ice sheet) has a younger minimum exposure age of only 8.8 ka. The minimum exposure ages for two bedrock samples from Blundell Peak (the highest peak on Stornes Peninsula, Larsemann Hills; ,2 km from the ice sheet) are about 17 and 18 ka. On the Bolingen Islands (southwest to the Larsemann Hills; ,10 km from the ice sheet), the minimum exposure age for one bedrock sample is similar to that at Friendship Mountain (i.e., 44 ka). Our results indicate that the bedrock exposure in the Larsemann Hills and on the neighboring Bolingen Islands commenced obviously before the global LGM (i.e., 20,22 ka), and the bedrock erosion rates at the Antarctic coast areas may be obviously higher than in the interior land. [source] Child sexual abuse in the etiology of depression: A systematic review of reviewsDEPRESSION AND ANXIETY, Issue 7 2010Roberto Maniglio Psy.D. Ph.D. Abstract Background: Despite a large amount of research, there is considerable controversy about the role that child sexual abuse plays in the etiology of depression. To prevent interpretative difficulties, mistaken beliefs, or confusion among professionals who turn to this literature for guidance, this article addresses the best available scientific evidence on the topic, by providing a systematic review of the several reviews that have investigated the literature on the issue. Methods: Seven databases were searched, supplemented with hand search of reference lists from retrieved papers. The author and a psychiatrist independently evaluated the eligibility of all studies identified, abstracted data, and assessed study quality. Disagreements were resolved by consensus. Results: Four reviews, including about 60,000 subjects from 160 studies and having no limitations that could invalidate their results, were analyzed. There is evidence that child sexual abuse is a significant, although general and nonspecific, risk factor for depression. The relationship ranges from small-to-medium in magnitude and is moderated by sample source. Additional variables may either act independently to promote depression in people with a history of sexual abuse or interact with such traumatic experience to increase the likelihood of depression in child abuse survivors. Conclusions: For all victims of abuse, programs should focus not only on treating symptoms, but also on reducing additional risk factors. Depressed adults who seek psychiatric treatment should be enquired about early abuse within admission procedures. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc. [source] When marital interaction and intervention researchers arrive at different points of view: the active listening controversyJOURNAL OF FAMILY THERAPY, Issue 1 2003McArthur Hafen Jr In 1998, John Gottman and his associates published an article which asserted that training ,active listening' between couples was an ineffective therapeutic intervention. Not surprisingly, this claim generated considerable controversy, particularly in relation to treatment and educational models that were heavily dependent on active listening as a major part of their intervention programmes. The authors of one such approach, the Prevention and Relationship Enhancement Program (PREP), were particularly vocal in their disagreement with Gottman's conclusions. This paper provides an account of the controversy, a summary of the current status of the debate and a discussion of the remaining unanswered questions. [source] A reconstruction of development of the periodic table based on history and philosophy of science and its implications for general chemistry textbooksJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 1 2005Angmary Brito The objectives of this study are: (a) elaboration of a history and philosophy of science (HPS) framework based on a reconstruction of the development of the periodic table; (b) formulation of seven criteria based on the framework; and (c) evaluation of 57 freshman college-level general chemistry textbooks with respect to the presentation of the periodic table. The historical reconstruction of the periodic table showed that the periodicity of the elements could be construed as an inductive generalization or as a function of the atomic theory. There is considerable controversy with respect to the nature of Mendeleev's contribution, and various alternatives are discussed: ordered domain; empirical law; and a theory with limited explanatory power. Accommodation of the elements according to their physicochemical properties is considered to be the major contribution of the periodic table by all textbooks, followed by contrapredictions of previously unknown elements (30 textbooks), and novel predictions (corrections of atomic mass) of known elements (10 textbooks). The relative importance of accommodation and prediction within an HPS framework is generally ignored. Few textbooks have attempted to explore the possible cause of periodicity in the table and very few textbooks have explored the nature of Mendeleev's contribution. The development of the periodic table as a sequence of heuristic principles in the form of a convincing argument has been ignored. The textbook approach of emphasizing that the development of the periodic table was an inductive generalization, and that Mendeleev had no model or theory, does not facilitate the spirit of critical inquiry that led the scientists to grapple with alternative interpretations, conflicts, and controversies. It is concluded that the development of the periodic table went through a continual critical appraisal (conflict and controversy), in which scientists presented various tentative theoretical ideas to understand the observed phenomena. © 2004 Wiley Periodicals, Inc. J Res Sci Teach 42: 84,111, 2005 [source] Body Mass Index Measurement in Schools,JOURNAL OF SCHOOL HEALTH, Issue 10 2007Allison J. Nihiser MPH ABSTRACT Background:, School-based body mass index (BMI) measurement has attracted much attention across the nation from researchers, school officials, legislators, and the media as a potential approach to address obesity among youth. Methods:, An expert panel, convened by the Centers for Disease Control and Prevention (CDC) in 2005, reviewed and provided expertise on an earlier version of this article. The panel comprised experts in public health, education, school counseling, school medical care, and a parent organization. This article describes the purposes of BMI measurement programs, examines current practices, reviews existing research, summarizes the recommendations of experts, identifies concerns, and provides guidance including a list of safeguards and ideas for future research. Results:, The implementation of school-based BMI measurement for surveillance purposes, that is, to identify the percentage of students in a population who are at risk for weight-related problems, is widely accepted; however, considerable controversy exists over BMI measurement for screening purposes, that is, to assess the weight status of individual students and provide this information to parents with guidance for action. Although some promising results have been reported, more evaluation is needed to determine whether BMI screening programs are a promising practice for addressing obesity. Conclusions:, Based on the available information, BMI screening meets some but not all of the criteria established by the American Academy of Pediatrics for determining whether screening for specific health conditions should be implemented in schools. Schools that initiate BMI measurement programs should evaluate the effects of the program on BMI results and on weight-related knowledge, attitudes, and behaviors of youth and their families; they also should adhere to safeguards to reduce the risk of harming students, have in place a safe and supportive environment for students of all body sizes, and implement science-based strategies to promote physical activity and healthy eating. [source] Frege's Judgement Stroke and the Conception of Logic as the Study of Inference not ConsequencePHILOSOPHY COMPASS (ELECTRONIC), Issue 4 2009Nicholas J. J. Smith One of the most striking differences between Frege's Begriffsschrift (logical system) and standard contemporary systems of logic is the inclusion in the former of the judgement stroke: a symbol which marks those propositions which are being asserted, that is, which are being used to express judgements. There has been considerable controversy regarding both the exact purpose of the judgement stroke, and whether a system of logic should include such a symbol. This paper explains the intended role of the judgement stroke in a way that renders it readily comprehensible why Frege insisted that this symbol was an essential part of his logical system. The key point here is that Frege viewed logic as the study of inference relations amongst acts of judgement, rather than , as in the typical contemporary view , of consequence relations amongst certain objects (propositions or well-formed formulae). The paper also explains why Frege's use of the judgement stroke is not in conflict with his avowed anti-psychologism, and why Wittgenstein's criticism of the judgement stroke as ,logically quite meaningless' is unfounded. The key point here is that while the judgement stroke has no content, its use in logic and mathematics is subject to a very stringent norm of assertion. [source] Issues and concerns of couples presenting for preimplantation genetic diagnosis (PGD)PRENATAL DIAGNOSIS, Issue 12 2002Mandy G. Katz Abstract Background The use of preimplantation genetic diagnosis (PGD) to select genetically ,normal' human embryos and to transfer them to the uterus of a woman has generated considerable controversy. Debate has occurred over the implications of PGD, sex selection, safety of embryonic manipulation and eugenics. This study evaluates a range of social and moral concerns of couples towards PGD and assisted reproductive technologies (ART) prior to treatment to obtain unbiased authentic attitudes independent of the treatment cycle and the outcome. Methods A total of 121 subjects were administered a structured questionnaire after each couple's in vitro fertilization (IVF) or genetic counselling session. Group A consisted of 41 subjects presenting for PGD of single gene disorders (PGD-SG) and group B consisted of 48 subjects undertaking PGD for aneuploidy screening (PGD-AS). A control group consisted of 32 subjects that were about to commence their first IVF cycle. Results and discussion All groups found PGD to be a highly acceptable treatment. They expressed little concern about its extension to testing non-disease states such as sex and they were strongly in favour of a shared decision-making model in which couples have considerable autonomy over decisions about the embryo(s) to transfer. Differences between the groups included issues surrounding the transfer of embryos, restrictions to PGD and the destruction of embryos. Copyright © 2002 John Wiley & Sons, Ltd. [source] Development of the blood-brain barrier: A historical point of viewTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 1 2006Domenico Ribatti Abstract Although there has been considerable controversy since the observation by Ehrlich more than 100 years ago that the brain did not take up dyes from the vascular system, the concept of an endothelial blood-brain barrier (BBB) was confirmed by the unequivocal demonstration that the passage of molecules from blood to brain and vice versa was prevented by endothelial tight junctions (TJs). There are three major functions implicated in the term "BBB": protection of the brain from the blood milieu, selective transport, and metabolism or modification of blood- or brain-borne substances. The BBB phenotype develops under the influence of associated brain cells, especially astrocytic glia, and consists of complex TJs and a number of specific transport and enzyme systems that regulate molecular traffic across the endothelial cells. The development of the BBB is a complex process that leads to endothelial cells with unique permeability characteristics due to high electrical resistance and the expression of specific transporters and metabolic pathways. This review article summarizes the historical background underlying our current knowledge of the cellular and molecular mechanisms involved in the development and maintenance of the BBB. Anat Rec (Part B: New Anat) 289B:3,8, 2006. © 2006 Wiley-Liss, Inc. [source] The American Right and the Framing of 9/11THE POLITICAL QUARTERLY, Issue 1 2004Martin Durham ABSTRACT On September 11th, 2001, 2 hijacked airliners were crashed into the World Trade Center and a third into the Pentagon. The Bush administration's response, both in regard to civil liberties at home and the launching of military action abroad, has been the subject of considerable controversy. As we might expect, the Bush administration's framing of events met with acclaim among many on the American right But here, as elsewhere on the political spectrum, how to understand and react to 9/11 was also the subject of bitter dispute, a dispute that sheds new light on the ongoing arguments among American conservatives in the aftermath of the Cold War. [source] Monoclinic PZN-8%PT [Pb(Zn0.3066Nb0.6133Ti0.08)O3] at 4,KACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2007Jennifer S. Forrester The structure of the relaxor ferroelectric Pb(Zn0.3066Nb0.6133Ti0.08)O3 (lead zinc niobium titanium trioxide), known as PZN-8%PT, was determined at 4,K from very high resolution neutron powder diffraction data. The material is known for its extraordinary piezoelectric properties, which are closely linked to the structure. Pseudo-cubic lattice parameters have led to considerable controversy over the symmetry of the structure. We find the structure to be monoclinic in the space group Cm (No. 8), with the Zn, Nb and Ti cations sharing the octahedrally coordinated B site (site symmetry m, special position 2a) and Pb occupying the 12-coordinate A site (site symmetry m, special position 2a). O atoms occupy a disorted octahedron around the B site (site symmetry m and special position 2a, and site symmetry 1 and general position 4b). Atomic coordinates have been determined for the first time, allowing the direction of spontaneous polarization to be visualized. [source] Field-Flow Fractionation as Analytical Technique for the Characterization of Dry Yeast: Correlation with Wine Fermentation ActivityBIOTECHNOLOGY PROGRESS, Issue 6 2003Ramsés Sanz Important oenological properties of wine depend on the winemaking yeast used in the fermentation process. There is considerable controversy about the quality of yeast, and a simple and cheap analytical methodology for quality control of yeast is needed. Gravitational field flow fractionation (GFFF) was used to characterize several commercial active dry wine yeasts from Saccharomycescerevisiae and Saccharomyces bayanus and to assess the quality of the raw material before use. Laboratory-scale fermentations were performed using two different S. cerevisiae strains as inocula, and GFFF was used to follow the behavior of yeast cells during alcoholic fermentation. The viable/nonviable cell ratio was obtained by flow cytometry (FC) using propidium iodide as fluorescent dye. In each experiment, the amount of dry wine yeast to be used was calculated in order to provide the same quantity of viable cells. Kinetic studies of the fermentation process were performed controlling the density of the must, from 1.071 to 0.989 (20/20 density), and the total residual sugars, from 170 to 3 g/L. During the wine fermentation process, differences in the peak profiles obtained by GFFF between the two types of commercial yeasts that can be related with the unlike cell growth were observed. Moreover, the strains showed different fermentation kinetic profiles that could be correlated with the corresponding fractograms monitored by GFFF. These results allow optimism that sedimentation FFF techniques could be successfully used for quality assessment of the raw material and to predict yeast behavior during yeast-based bioprocesses such as wine production. [source] The increasing prevalence of allergy: a challenge for the physicianCLINICAL & EXPERIMENTAL ALLERGY REVIEWS, Issue 1 2002R. Mösges Summary The prevalence of allergic disorders has increased markedly throughout the world during the past three decades. There has been considerable controversy about the extent to which the increase is real, or attributable to increased awareness or better diagnosis. It seems probable that the increased prevalence is real because longitudinal studies have shown a rapid exponential increase in allergic disorders such as asthma. Since there is a marked difference in the occurrence of allergic disorders between Western and less developed countries, as well as between rural and urban areas, it is likely that environmental (,lifestyle') factors are aetiologically involved. It also seems probable that contact with microbial antigens, in the form of childhood infections, vaccinations and contact with farm animals, can exert some protection against the later development of allergies. Studies are in progress to determine whether reduction in risk factors or intervention with anti-allergic therapies can modify the long-term outcome in populations at high risk. [source] | ||||||||||||||||