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11.
We give a parametrized family of rational interval maps of degree two, each ergodic, exact and preserving a measure equivalent to a Lebesgue measure. The family includes the unique quadratic Chebyshev polynomial as its only polynomial map. We extend the family to other settings on the circle and real line. We also give numerical approximations to the entropy of the equivalent invariant measure and the Hausdorff dimension of the singular measure of maximal entropy. 相似文献
12.
Haley William E.; Larson Dale G.; Kasl-Godley Julia; Neimeyer Robert A.; Kwilosz Donna M. 《Canadian Metallurgical Quarterly》2003,34(6):626
Professional psychologists are increasingly likely to encounter opportunities to work with patients and families facing end-of-life issues. Psychologists can provide psychological assessment, intervention for patients and families, consultation with and support of health care team members, grief therapy, and program development and evaluation. Psychological services are useful for healthy individuals who wish to make thoughtful plans about their own future care, patients with life-limiting illnesses, families stressed by providing end-of-life care, bereaved individuals, and health care providers who face issues of burnout and strain. Several challenges for psychologists working in end-of-life care are noted, including training, development of clear roles, and reimbursement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
Simpson Jeffry A.; Rholes William S.; Nelligan Julia S. 《Canadian Metallurgical Quarterly》1992,62(3):434
Examined how adult attachment styles moderate spontaneous behavior between dating couples when 1 member of the dyad is confronted with an anxiety-provoking situation. 83 dating couples were unobtrusively videotaped for 5 min in a waiting room while the woman waited to participate in an "activity" known to provoke anxiety in most people. Independent observers then evaluated each partner's behavior on several dimensions. Results revealed that persons with more secure attachment styles behaved differently than persons with more avoidant styles in terms of physical contact, supportive comments, and efforts to seek and give emotional support. Findings are discussed in the context of theory and research on attachment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
14.
G Pons-Lladó F Carreras X Borrás J Palmer J Llauger A Bayés de Luna 《Canadian Metallurgical Quarterly》1997,79(12):1651-1656
To compare the value of echocardiography and magnetic resonance imaging (MRI) in the assessment of the amount and extent of hypertrophy in hypertrophic cardiomyopathy (HC) and, second, to correlate the degree of hypertrophy, as assessed by MRI, with clinical and electrocardiographic parameters, 30 consecutive patients (16 men and 14 women, aged 20 to 74 years) with HC were studied. Measurements of left ventricular wall thickness were performed at 11 predetermined segments (5 basal, 5 midventricular, and 1 apical) by 2-dimensional echocardiography and MRI. Two parameters derived from MRI studies were considered as indicators of the degree and extent of hypertrophy: (1) mean of the measured wall thickness at the 11 segments, and (2) the number of segments with thickness > 15 mm. Results showed that, from a total of 330 myocardial segments, thickness could be measured by echocardiography in 221 (67%), whereas MRI allowed measurement of 320 segments (97%). When compared with clinical and electrocardiographic data, no correlation was found regarding mean wall thickness and number of hypertrophied segments by MRI except for the presence of an abnormal electrocardiographic repolarization pattern. It is concluded that MRI allows a better assessment of the degree and extension of left ventricular hypertrophy than echocardiography in HC. Despite the precise information on hypertrophy provided by MRI, the amount and degree of hypertrophy bears no correlation with most of the clinical data in these patients. 相似文献
15.
Snell-Johns Jessica; Mendez Julia L.; Smith Bradley H. 《Canadian Metallurgical Quarterly》2004,18(1):19
Various definitions exist for what constitutes family therapy. In this article, we consider family therapy to encompass any intervention that targets family interactions and conceptualizes problems as existing beyond individual clients. Numerous individual studies and several quantitative reviews have established family therapy as an effective treatment modality and the treatment of choice for many disorders. However, critiques of existing service provision highlight the unfortunate fact that numerous barriers to treatment exist at multiple levels of the broader ecology, preventing many families from benefiting from these services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
Extending the power line LAN up to the neighborhood transformer 总被引:1,自引:0,他引:1
Abad J. Badenes A. Blasco J. Carreras J. Dominguez V. Gomez C. Iranzo S. Riveiro J.C. Ruiz D. Torres L.M. Comabella J. 《Communications Magazine, IEEE》2003,41(4):64-70
This article reports on the performance of audio, video, multimedia, and other high-data-rate in-home networking applications. The article starts by describing the problems encountered in power line communication channels in terms of frequency response and noise characteristics, and explains how in-home power line LANs can be extended to the neighborhood transformer. OFDM physical layers providing speeds of 45 Mb/s and 200 Mb/s as well as QoS and security are introduced. Finally, the results of large tests involving several thousands of nodes are described. 相似文献
17.
Sigal Gottlieb Julia S. Mullen Steven J. Ruuth 《Journal of scientific computing》2006,27(1-3):271-287
The weighted essentially non-oscillatory (WENO) method is an excellent spatial discretization for hyperbolic partial differential equations with discontinuous solutions. However, the time-step restriction associated with explicit methods may pose severe limitations on their use in applications requiring large scale computations. An efficient implicit WENO method is necessary. In this paper, we propose a prototype flux-implicit WENO (iWENO) method. Numerical tests on classical scalar equations show that this is a viable and stable method, which requires appropriate time-stepping methods. Future study will include the examination of such methods as well as extension of iWENO to systems and higher dimensional problems.Sigal Gottlieb - The work of this author supported by NSF grant DMS-0106743.Steven J. Ruuth - The work of this author was partially supported by a grant from NSERC Canada. 相似文献
18.
This research was an investigation of children's performance on a task that requires memory binding. In Experiments 1 and 2, 4-year-olds, 6-year-olds, and adults viewed complex pictures and were tested on memory for isolated parts in the pictures and on the part combinations (combination condition). The results suggested improvement in memory for the combinations between the ages of 4 and 6 years but not in memory for the isolated parts. In Experiments 2 and 3, the authors also examined the developmental relationship between performance in the combination condition and free recall of a naturalistic event, finding preliminary evidence that performance on a memory task that requires binding is positively related to performance in episodic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
103 undergraduates listened to and recalled 3 passages and were given a general reading comprehension test. The passages were presented such that Ss could use general knowledge to understand them or such that no specific world knowledge seemed applicable. The passages were written in 2 different versions, preserving their content but varying their style. All 3 factors (domain knowledge, writing style, and skill) significantly affected reproductive recall, and there were no interactions between these factors. However, while good writing was sufficient to improve the reproduction of the texts, an analysis of the recall elaborations Ss made revealed that the correctness of their elaborations depended strongly on the availability of appropriate domain knowledge. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
A Gratwohl J Hermans JM Goldman W Arcese E Carreras A Devergie F Frassoni G Gahrton HJ Kolb D Niederwieser T Ruutu JP Vernant T de Witte J Apperley 《Canadian Metallurgical Quarterly》1998,352(9134):1087-1092
BACKGROUND: Transplantation of blood or bone-marrow stem cells is the treatment of choice for selected patients with chronic myeloid leukaemia (CML). Transplantation is used with increasing frequency and success, but remains associated with substantial risks of morbidity and mortality. Other treatments with satisfactory short-term outcome are available. For appropriate counselling of patients, a rapid and simple way to assess risk is needed. METHODS: Data from 3142 patients (1873 [60%] male, 1269 [40%] female; mean age 34 years, range <1-60 years) treated with allogeneic blood or marrow transplants for CML between 1989 and 1997, reported to the European Group for Blood and Marrow Transplantation (EBMT), were used to develop and test a simple risk score based on previously reported major pretransplant risk factors: histocompatibility, stage of disease at time of transplantation, age and sex of donor and recipient, and time from diagnosis to transplantation. We analysed probabilities of survival, leukaemia-free survival, transplant-related mortality, and relapse incidence with respect to these risk factors. FINDINGS: At the time of analysis, 1922 (61%) of the 3142 patients were alive-1567 (65%) of those with HLA-identical sibling donors and 417 (57%) of those with unrelated donors. 1682 (54%) were alive without relapse. 1220 (39%) patients had died, 1013 (83%) of transplant-related causes, 207 (17%) of relapse. 447 (14%) patients had relapsed. The final scoring system was highly predictive for leukaemia-free survival, survival and transplant-related mortality. Survival at 5 years was 72%, 70%, 62%, 48%, 40%, 18%, and 22% for patients with scores 0, 1, 2, 3, 4, 5, and 6, respectively. Risk of transplant-related mortality was 20%, 23%, 31%, 46%, 51%, 71%, and 73%. Data showed the same trends for HLA-identical sibling transplants and unrelated transplants for transplants done in 1989-93 and 1994-96. INTERPRETATION: Pretransplant risk factors are cumulative for individual patients with CML having blood or marrow transplantation. A simple system based on five main factors gives adequate risk assessment for counselling of patients and taking decisions. 相似文献