955 resultados para dimensionless chart


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While dehydration is common in older patients and is associated with poor outcomes, it has been infrequently studied in the hospital setting. Thus, the aim of this study was to identify potential barriers and enablers to the maintenance of adequate hydration in older patients in an acute hospital environment. An observational study, involving patients aged 60 years and older admitted to an acute care hospital in Queensland, Australia, was undertaken. Forty-four patients were observed during mealtimes, and chart and room audits were performed to identify hydration management strategies, weight records and the presence or absence of fluid balance charts. Results revealed a number of system and practice-related barriers including patient difficulties with opening fluid containers and low levels of documentation of hydration management strategies. Addressing these issues is an important first step towards improving the management of hydration in medically ill older hospital patients.

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Family tree, genealogical notes and master chart for the Adler family in Warburg, prepared by Claude Corty.

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The paper studies the influence of vectored suction or injection on the flow and heat transfer at the stagnation point of a two-dimensional body (a cylinder) and an axisymmetric body (a sphere) with allowance for the effects of variable gas properties. The analysis is based on the boundary-layer equations in dimensionless form for the steady compressible fluid with variable properties in the stagnation region of a two-dimensional or an axisymmetric body with tangential and normal surface mass transfer under similarity requirements. It is shown that the variation of the density-viscosity product across the boundary layer has a strong effect on the skin friction and heat transfer. This gives rise to a point of inflection which can be removed by suction and by increasing the wall temperature. The skin friction and heat transfer are significantly affected by the pressure gradient parameter.

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In this paper we consider HCI's role in technology interventions for health and well-being. Three projects carried out by the authors are analysed by appropriating the idea of a value chain to chart a causal history from proximal effects generated in early episodes of design through to distal health and well-being outcomes. Responding to recent arguments that favour bounding HCI's contribution to local patterns of use, we propose an unbounded view of HCI that addresses an extended value chain of influence. We discuss a view of HCI methods as mobilising this value chain perspective in multi-disciplinary collaborations through its emphasis on early prototyping and naturalistic studies of use.

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The symbols, signs, and traces of copyright and related intellectual property laws that appear on everyday texts, objects, and artifacts have multiplied exponentially over the past 15 years. Digital spaces have revolutionized access to content and transformed the ways in which content is porous and malleable. In this volume, contributors focus on copyright as it relates to culture. The editors argue that what «counts» as property must be understood as shifting terrain deeply influenced by historical, economic, cultural, religious, and digital perspectives. Key themes addressed include issues of how: • Culture is framed, defined, and/or identified in conversations about intellectual property; • The humanities and other related disciplines are implicated in intellectual property issues; • The humanities will continue to rub up against copyright (e.g., issues of authorship, authorial agency, ownership of texts); • Different cultures and bodies of literature approach intellectual property, and how competing dynasties and marginalized voices exist beyond the dominant U.S. copyright paradigm. Offering a transnational and interdisciplinary perspective, Cultures of Copyright offers readers – scholars, researchers, practitioners, theorists, and others – key considerations to contemplate in terms of how we understand copyright’s past and how we chart its futures.

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The flow, heat and mass transfer problem for boundary layer swirling flow of a laminar steady compressible electrically conducting gas with variable properties through a conical nozzle and a diffuser with an applied magnetic field has been studied. The partial differential equations governing the flow have been solved numerically using an implicit finite-difference scheme after they have been transformed into dimensionless form using the modified Lees transformation. The results indicate that the skin friction and heat transfer strongly depend on the magnetic field, mass transfer and variation of the density-viscosity product across the boundary layer. However, the effect of the variation of the density-viscosity product is more pronounced in the case of a nozzle than in the case of a diffuser. It has been found that large swirl is required to produce strong effect on the skin friction and heat transfer. Separationless flow along the entire length of the diffuser can be obtained by applying appropriate amount of suction. The results are found to be in good agreement with those of the local nonsimilarity method, but they differ quite significantly from those of the local similarity method.

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Spatial variations in the concentration of a reactive solute in solution are often encountered in a catalyst particle, and this leads to variation in the freezing point of the solution. Depending on the operating temperature, this can result in freezing of the solvent oil a portion of catalyst, rendering that part of the active area ineffective Freezing call occur by formation of a sharp front or it mush that separates the solid and fluid phases. In this paper, we model the extent of reduction in the active area due to freezing. Assuming that the freezing point decreases linearly with solute concentration, conditions for freezing to occur have been derived. At steady state, the ineffective fraction of catalyst pellet is found to be the same irrespective of the mode of freezing. Progress of freezing is determined by both the heat of reaction and the latent heat of fusion Unlike in freezing of alloys where the latter plays a dominant role, the exothermicity of the reaction has a significant effect on freezing in the presence of chemical reactions. A dimensionless group analogous to the Stefan number could be defined to capture the combined effect of both of these.

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A non-dimensional parameter descriptive of the plowing nature of surfaces is proposed for the case of sliding between a soft and a relatively hard metallic pair. From a set of potential parameters which can be descriptive of the phenomenon, dimensionless groups are formulated and the influence of each one of them is analyzed. A non-dimensional parameter involving the root-mean square deviation (R-q) and the centroidal frequency (F-mean) deducted from the power-spectrum is found to have a high degree of correlation (as high as 0.93) with the coefficient of friction obtained in sliding experiments under lubricated condition.

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The conventional Clauser-chart method for determination of local skin friction in zero or weak pressure-gradient turbulent boundary layer flows fails entirely in strong pressure-gradient situations. This failure occurs due to the large departure of the mean velocity profile from the universal logarithmic law upon which the conventional Clauser-chart method is based. It is possible to extend this method,even for strong pressure-gradient situations involving equilibrium or near-equilibrium turbulent boundary layers by making use of the so-called non-universal logarithmic laws. These non-universal log laws depend on the local strength of the pressure gradient and may be regarded as perturbations of the universal log law.The present paper shows that the modified Clauser-chart method, so developed, yields quit satisfactory results in terms of estimation of local skin friction in strongly accelerated or retarded equilibrium and near-equilibrium turbulent boundary layers that are not very close to relaminarization or separation.

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The dynamics of loop formation by linear polymer chains has been a topic of several theoretical and experimental studies. Formation of loops and their opening are key processes in many important biological processes. Loop formation in flexible chains has been extensively studied by many groups. However, in the more realistic case of semiflexible polymers, not much results are available. In a recent study [K. P. Santo and K. L. Sebastian, Phys. Rev. E 73, 031923 (2006)], we investigated opening dynamics of semiflexible loops in the short chain limit and presented results for opening rates as a function of the length of the chain. We presented an approximate model for a semiflexible polymer in the rod limit based on a semiclassical expansion of the bending energy of the chain. The model provided an easy way to describe the dynamics. In this paper, using this model, we investigate the reverse process, i.e., the loop formation dynamics of a semiflexible polymer chain by describing the process as a diffusion-controlled reaction. We make use of the ``closure approximation'' of Wilemski and Fixman [G. Wilemski and M. Fixman, J. Chem. Phys. 60, 878 (1974)], in which a sink function is used to represent the reaction. We perform a detailed multidimensional analysis of the problem and calculate closing times for a semiflexible chain. We show that for short chains, the loop formation time tau decreases with the contour length of the polymer. But for longer chains, it increases with length obeying a power law and so it has a minimum at an intermediate length. In terms of dimensionless variables, the closing time is found to be given by tau similar to L-n exp(const/L), where n=4.5-6. The minimum loop formation time occurs at a length L-m of about 2.2-2.4. These are, indeed, the results that are physically expected, but a multidimensional analysis leading to these results does not seem to exist in the literature so far.

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Background and aims. Since 1999, hospitals in the Finnish Hospital Infection Program (SIRO) have reported data on surgical site infections (SSI) following major hip and knee surgery. The purpose of this study was to obtain detailed information to support prevention efforts by analyzing SIRO data on SSIs, to evaluate possible factors affecting the surveillance results, and to assess the disease burden of postoperative prosthetic joint infections in Finland. Methods. Procedures under surveillance included total hip (THA) and total knee arthroplasties (TKA), and the open reduction and internal fixation (ORIF) of femur fractures. Hospitals prospectively collected data using common definitions and written protocol, and also performed postdischarge surveillance. In the validation study, a blinded retrospective chart review was performed and infection control nurses were interviewed. Patient charts of deep incisional and organ/space SSIs were reviewed, and data from three sources (SIRO, the Finnish Arthroplasty Register, and the Finnish Patient Insurance Centre) were linked for capture-recapture analyses. Results. During 1999-2002, the overall SSI rate was 3.3% after 11,812 orthopedic procedures (median length of stay, eight days). Of all SSIs, 56% were detected after discharge. The majority of deep incisional and organ/space SSIs (65/108, 60%) were detected on readmission. Positive and negative predictive values, sensitivity, and specificity for SIRO surveillance were 94% (95% CI, 89-99%), 99% (99-100%), 75% (56-93%), and 100% (97-100%), respectively. Of the 9,831 total joint replacements performed during 2001-2004, 7.2% (THA 5.2% and TKA 9.9%) of the implants were inserted in a simultaneous bilateral operation. Patients who underwent bilateral operations were younger, healthier, and more often males than those who underwent unilateral procedures. The rates of deep SSIs or mortality did not differ between bi- and uni-lateral THAs or TKAs. Four deep SSIs were reported following bilateral operations (antimicrobial prophylaxis administered 48-218 minutes before incision). In the three registers, altogether 129 prosthetic joint infections were identified after 13,482 THA and TKA during 1999-2004. After correction with the positive predictive value of SIRO (91%), a log-linear model provided an estimated overall prosthetic joint infection rate of 1.6% after THA and 1.3% after TKA. The sensitivity of the SIRO surveillance ranged from 36% to 57%. According to the estimation, nearly 200 prosthetic joint infections could occur in Finland each year (the average from 1999 to 2004) after THA and TKA. Conclusions. Postdischarge surveillance had a major impact on SSI rates after major hip and knee surgery. A minority of deep incisional and organ/space SSIs would be missed, however, if postdischarge surveillance by questionnaire was not performed. According to the validation study, most SSIs reported to SIRO were true infections. Some SSIs were missed, revealing some weakness in case finding. Variation in diagnostic practices may also affect SSI rates. No differences were found in deep SSI rates or mortality between bi- and unilateral THA and TKA. However, patient materials between these two groups differed. Bilateral operations require specific attention paid to their antimicrobial prophylaxis as well as to data management in the surveillance database. The true disease burden of prosthetic joint infections may be heavier than the rates from national nosocomial surveillance systems usually suggest.

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Much of what we know regarding the long-term course and outcome of major depressive disorder (MDD) is based on studies of mostly inpatient tertiary level cohorts and samples predating the era of the current antidepressants and the use of maintenance therapies. In addition, there is a lack of studies investigating the comprehensive significance of comorbid axis I and II disorders on the outcome of MDD. The present study forms a part of the Vantaa Depression Study (VDS), a regionally representative prospective and naturalistic cohort study of 269 secondary-level care psychiatric out- and inpatients (aged 20-59) with a new episode of DSM-IV MDD, and followed-up up to five years (n=182) with a life-chart and semistructured interviews. The aim was to investigate the long-term outcome of MDD and risk factors for poor recovery, recurrences, suicidal attempts and diagnostic switch to bipolar disorder, and the association of a family history of different psychiatric disorders on the outcome. The effects of comorbid disorders together with various other predictors from different domains on the outcome were comprehensively investigated. According to this study, the long-term outcome of MDD appears to be more variable when its outcome is investigated among modern, community-treated, secondary-care outpatients compared to previous mostly inpatient studies. MDD was also highly recurrent in these settings, but the recurrent episodes seemed shorter, and the outcome was unlikely to be uniformly chronic. Higher severity of MDD predicted significantly the number of recurrences and longer time spent ill. In addition, longer episode duration, comorbid dysthymic disorder, cluster C personality disorders and social phobia predicted a worse outcome. The incidence rate of suicide attempts varied robustly de¬pending on the level of depression, being 21-fold during major depressive episodes (MDEs), and 4-fold during partial remission compared to periods of full remission. Although a history of previous attempts and poor social support also indicated risk, time spent depressed was the central factor determining overall long-term risk. Switch to bipolar disorder occurred mainly to type II, earlier to type I, and more gradually over time to type II. Higher severity of MDD, comorbid social phobia, obsessive compulsive disorder, and cluster B personality disorder features predicted the diagnostic switch. The majority of patients were also likely to have positive family histories not exclusively of mood, but also of other mental disorders. Having a positive family history of severe mental disorders was likely to be clinically associated with a significantly more adverse outcome.

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The Jorvi Bipolar Study (JoBS) is a collaborative ongoing bipolar research project between the Department of Mental Health and Alcohol Research of the National Public Health Institute, Helsinki, and the Department of Psychiatry, Jorvi Hospital, Helsinki University Central Hospital (HUCH), Espoo, Finland. The JoBS is a prospective, naturalistic cohort study of secondary level care psychiatric out-and inpatients with a new episode of Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) bipolar disorder (BD). Altogether, 1630 patients (aged 18-59) years were screened using the Mood Disorder Questionnaire (MDQ) for a possible new episode of DSM-IV BD. 490 patients were interviewed with semi-structured interview [the Structured Clinical Interview for DSM-IV Disorders, research version with Psychotic Screen (SCID-I/P)]. 191 patients with new episode of DSM-IV BD were included in the bipolar cohort study. Psychiatric comorbidity was evaluated using semi-structured interviews. At 6- and 18-month follow-up, the interviews were repeated and life-chart methodology was used to integrate all available information about nature and duration of all different phases. Suicidal behaviour was examined both at intake and follow-up by psychometric scale [Scale for Suicidal Ideation (SSI)], interviewer s questions and medical and psychiatric records. The aim of this thesis was to evaluate prevalence of suicidal behaviour and incidence of suicide attempts, and examine the wide range of risk factors for attempted suicide both, at intake and follow-up, in representative secondary-level sample of psychiatric in- and outpatients with BD. In this study suicidal behaviour was common among psychiatric patients with BD. During the episode when patients were included into cohort study (index episode), 20% of the patients had attempted suicide and 61% had suicidal ideation. Severity of depressive episode and hopelessness were independent risk factors for suicidal ideation, whereas hopelessness, comorbid personality disorder and previous suicide attempt predicted suicide attempts during the index episode. There were no differences in prevalence of suicidal behaviour between bipolar I and II disorder; the risk factors were overlapping but not identical. During the index episode, suicide attempts took place during depressive, mixed and depressive mixed phases. Furthermore, there were marked differences regarding level of suicidal ideation during different phases, with the highest levels during the mixed phases of the illness. Hopelessness was independently associated with suicidal behaviour during the depressive phase. A subjective rating of severity of depression (Beck Depression Inventory) and younger age predicted suicide attempts during mixed phases. During the 18-month follow-up 20% of patients attempted suicide. Previous suicide attempts, hopelessness, depressive phase at index episode and younger age at intake were independent risk factors for suicide attempts during follow-up. Taken altogether, 55% patients attempted suicide before index episode, during index episode or during follow-up. The incidence of suicide attempts was 37-fold during combined mixed and depressive mixed states and 18-fold during major depressive phase as compared with other phases. Prior suicide attempt and time spent in combined mixed phases - mixed and depressive mixed - and depressive phases independently predicted the suicide attempt during follow-up. More than half of the patients have attempted suicide during their lifetime, a finding which highlights the public health importance of suicidal behaviour in bipolar disorder. Clinically, it is crucial to recognize BD and manage the mixed and depressive phases of bipolar patients fast and effectively, as time spent in depressive and mixed phases involves a remarkably high risk of suicide attempts.

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The Vantaa Primary Care Depression Study (PC-VDS) is a naturalistic and prospective cohort study concerning primary care patients with depressive disorders. It forms a collaborative research project between the Department of Mental and Alcohol Research of the National Public Health Institute, and the Primary Health Care Organization of the City of Vantaa. The aim is to obtain a comprehensive view on clinically significant depression in primary care, and to compare depressive patients in primary care and in secondary level psychiatric care in terms of clinical characteristics. Consecutive patients (N=1111) in three primary care health centres were screened for depression with the PRIME-MD, and positive cases interviewed by telephone. Cases with current depressive symptoms were diagnosed face-to-face with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I/P). A cohort of 137 patients with unipolar depressive disorders, comprising all patients with at least two depressive symptoms and clinically significant distress or disability, was recruited. The Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II), medical records, rating scales, interview and a retrospective life-chart were used to obtain comprehensive cross-sectional and retrospective longitudinal information. For investigation of suicidal behaviour the Scale for Suicidal Ideation (SSI), patient records and the interview were used. The methodology was designed to be comparable to The Vantaa Depression Study (VDS) conducted in secondary level psychiatric care. Comparison of major depressive disorder (MDD) patients aged 20-59 from primary care in PC-VDS (N=79) was conducted with new psychiatric outpatients (N =223) and inpatients (N =46) in VDS. The PC-VDS cohort was prospectively followed up at 3, 6 and 18 months. Altogether 123 patients (90%) completed the follow-up. Duration of the index episode and the timing of relapses or recurrences were examined using a life-chart. The retrospective investigation revealed current MDD in most (66%), and lifetime MDD in nearly all (90%) cases of clinically significant depressive syndromes. Two thirds of the “subsyndromal” cases had a history of major depressive episode (MDE), although they were currently either in partial remission or a potential prodromal phase. Recurrences and chronicity were common. The picture of depression was complicated by Axis I co-morbidity in 59%, Axis II in 52% and chronic Axis III disorders in 47%; only 12% had no co-morbidity. Within their lifetimes, one third (37%) had seriously considered suicide, and one sixth (17%) had attempted it. Suicidal behaviour clustered in patients with moderate to severe MDD, co-morbidity with personality disorders, and a history of treatment in psychiatric care. The majority had received treatment for depression, but suicidal ideation had mostly remained unrecognised. The comparison of patients with MDD in primary care to those in psychiatric care revealed that the majority of suicidal or psychotic patients were receiving psychiatric treatment, and the patients with the most severe symptoms and functional limitations were hospitalized. In other clinical aspects, patients with MDD in primary care were surprisingly similar to psychiatric outpatients. Mental health contacts earlier in the current MDE were common among primary care patients. The 18-month prospective investigation with a life-chart methodology verified the chronic and recurrent nature of depression in primary care. Only one-quarter of patients with MDD achieved and maintained full remission during the follow-up, while another quarter failed to remit at all. The remaining patients suffered either from residual symptoms or recurrences. While severity of depression was the strongest predictor of recovery, presence of co-morbid substance use disorders, chronic medical illness and cluster C personality disorders all contributed to an adverse outcome. In clinical decision making, beside severity of depression and co-morbidity, history of previous MDD should not be ignored by primary care doctors while depression there is usually severe enough to indicate at least follow-up, and concerning those with residual symptoms, evaluation of their current treatment. Moreover, recognition of suicidal behaviour among depressed patients should also be improved. In order to improve outcome of depression in primary care, the often chronic and recurrent nature of depression should be taken into account in organizing the care. According to literature management programs of a chronic disease, with enhancement of the role of case managers and greater integration of primary and specialist care, have been successful. Optimum ways of allocating resources between treatment providers as well as within health centres should be found.