Обернені сингулярно збурені задачі типу «конвекція-дифузія» для двозв’язних областей

Побудовано асимптотичне розвинення розв’язків сингулярно збурених крайових задач типу «конвекція-дифузія» з невідомим коефіцієнтом дифузії, який залежить від координат двозв’язної області. При побудові алгоритму використано перехід від вихідної постановки конвективно-дифузійної задачі у криволінійній двозв’язній області до періодичної задачі стосовно відповідної області комплексного потенціалу. Наведено результати числових розрахунків.The asymptotic expansion is constructed for solving singular disturbed boundary-value «convection-diffusion» problems with the unknown coefficient of diffusion which depends on physical coordinates of a double-connected area. Transition from the initial formulation of «convectional-diffusion» problems in curvilinear double-connected area to periodic task at the corresponding area complex potential is used to algorithm construction. The results of numerical calculations are given.Построено асимптотическое развитие решений сингулярно возмущенных краевых задач типа «конвекция-диффузия» с неизвестным коэффициентом диффузии, зависящем от координат двухсвязной области. При построении алгоритма использовано переход от исходной постановки конвективно-диффузионной задачи в криволинейной двусвязной области к периодической задаче относительно соответствующей области комплексного потенциала. Приведены результаты численных расчетов

Possible Sources of Bias in Primary Care Electronic Health Record Data Use and Reuse

Background - Enormous amounts of data are recorded routinely in health care as part of the care process, primarily for managing individual patient care. There are significant opportunities to use this data for other purposes, many of which would contribute to establishing a learning health system. This is particularly true for data recorded in primary care settings, as in many countries, these are the first place patients turn to for most health problems. Objective - In this paper, we discuss whether data that is recorded routinely as part of the health care process in primary care is actually fit to use for these other purposes, how the original purpose may affect the extent to which the data is fit for another purpose and the mechanisms behind these effects. In doing so, we want to identify possible sources of bias that are relevant for the (re-)use of this type of data. Methods –This discussion paper is based on the authors’ experience as users of electronic health records data, as a general practitioner, health informatics experts, and health services researchers. It is a product of the discussions they had during the TRANSFoRm project, which was funded by the EU and sought to develop, pilot and evaluate a core information architecture for the Learning Health System (LHS) in Europe, based on primary care electronic health records. Results – We first describe the different stages in the processing of EHR data, as well as the different purposes for which this data is used. Given the different data processing steps and purposes, we then discuss the possible mechanisms for each individual data processing step, that can generate biased outcomes. We identified thirteen possible sources of bias. Four of them are related to the organization of a health care system, some are of a more technical nature. Conclusions - There are a substantial number of possible sources of bias, and very little is known about the size and direction of their impact. However, any (re-)user of data that was recorded as part of the health care process (such as researchers and clinicians) should be aware of the associated data collection process and environmental influences that can affect the quality of the data. Our stepwise, actor and purpose oriented approach may help to identify these possible sources of bias. Unless data quality issues are better understood and unless adequate controls are embedded throughout the data lifecycle, data-driven healthcare will not live up to its expectations. We need a data quality research agenda to devise the appropriate instruments needed to assess the magnitude of each of the possible sources of bias, and then start measuring their impact. The possible sources of bias described in this paper serve as a starting point for this research agenda

Increased cocaine self-administration in rats lacking the serotonin transporter : a role for glutamatergic signaling in the habenula

Serotonin (5-HT) and the habenula (Hb) contribute to motivational and emotional states such as depression and drug abuse. The dorsal raphe nucleus, where 5-HT neurons originate, and the Hb are anatomically and reciprocally interconnected. Evidence exists that 5-HT influences Hb glutamatergic transmission. Using serotonin transporter knockout (SERT-/- ) rats, which show depression-like behavior and increased cocaine intake, we investigated the effect of SERT reduction on expression of genes involved in glutamate neurotransmission under both baseline conditions as well as after short-access or long-access cocaine (ShA and LgA, respectively) intake. In cocaine-na\uefve animals, SERT removal led to reduced baseline Hb mRNA levels of critical determinants of glutamate transmission, such as SLC1A2, the main glutamate transporter and N-methyl-D-aspartate (Grin1, Grin2A and Grin2B) as well as \u3b1-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (Gria1 and Gria2) receptor subunits, with no changes in the scaffolding protein Dlg4. In response to ShA and LgA cocaine intake, SLC1A2 and Grin1 mRNA levels decreased in SERT+/+ rats to levels equal of those of SERT-/- rats. Our data reveal that increased extracellular levels of 5-HT modulate glutamate neurotransmission in the Hb, serving as critical neurobiological substrate for vulnerability to cocaine addiction

The Stability of Comorbid Psychiatric Disorders: A 7 Year Follow Up of Children with Pervasive Developmental Disorder-Not Otherwise Specified

The current study was a 7-year follow-up of 74 6–12 year old children with Pervasive Developmental Disorder-Not Otherwise Specified. We examined the rates and 7 year stability of comorbid psychiatric diagnoses as ascertained with the Diagnostic Interview Schedule for Children: Parent version at ages 6–12 and again at ages 12–20. Also, we examined childhood factors that predicted the stability of comorbid psychiatric disorders. The rate of comorbid psychiatric disorders dropped significantly from childhood (81 %) to adolescence (61 %). Higher levels of parent reported stereotyped behaviors and reduced social interest in childhood significantly predicted the stability of psychiatric comorbidity. Re-evaluation of psychiatric comorbidity should be considered in clinical practice, since several individuals shifted in comorbid diagnoses

Fitness for purpose of routinely recorded health data to identify patients with complex diseases: The case of Sjögren's syndrome

Background: This study is part of the EU-funded project HarmonicSS, aimed at improving the treatment and diagnosis of primary Sjögren's syndrome (pSS). pSS is an underdiagnosed, long-term autoimmune disease that affects particularly salivary and lachrymal glands. Objectives: We assessed the usability of routinely recorded primary care and hospital claims data for the identification and validation of patients with complex diseases such as pSS. Methods: pSS patients were identified in primary care by translating the formal inclusion and exclusion criteria for pSS into a patient selection algorithm using data from Nivel Primary Care Database (PCD), covering 10% of the Dutch population between 2006 and 2017. As part of a validation exercise, the pSS patients found by the algorithm were compared to Diagnosis Related Groups (DRG) recorded in the national hospital insurance claims database (DIS) between 2013 and 2017. Results: International Classification of Primary Care (ICPC) coded general practitioner (GP) contacts combined with the mention of “Sjögren” in the disease episode titles, were found to best translate the formal classification criteria to a selection algorithm for pSS. A total of 1462 possible pSS patients were identified in primary care (mean prevalence 0.7‰, against 0.61‰ reported globally). The DIS contained 208 545 patients with a Sjögren related DRG or ICD10 code (prevalence 2017: 2.73‰). A total of 2 577 577 patients from Nivel PCD were linked to the DIS database. A total of 716 of the linked pSS patients (55.3%) were confirmed based on the DIS. Conclusion: Our study finds that GP electronic health records (EHRs) lack the granular information needed to apply the formal diagnostic criteria for pSS. The developed algorithm resulted in a patient selection that approximates the expected prevalence and characteristics, although only slightly over half of the patients were confirmed using the DIS. Without more detailed diagnostic information, the fitness for purpose of routine EHR data for patient identification and validation could not be determined

Is green space in the living environment associated with people's feelings of social safety?

Abstract. The authors investigate whether the percentage of green space in people's living environ- ment affects their feelings of social safety positively or negatively. More specifically they investigate the extent to which this relationship varies between urban and rural areas, between groups in the community that can be identified as more or less vulnerable, and the extent to which different types of green space exert different influences. The study includes 83736 Dutch citizens who were interviewed about their feelings of social safety. The percentage of green space in the living environment of each respondent was calculated, and data analysed by use of a three-level latent variable model, controlled for individual and environmental background characteristics. The analyses suggest that more green space in people's living environment is associated with enhanced feelings of social safetyöexcept in very strongly urban areas, where enclosed green spaces are associated with reduced feelings of social safety. Contrary to the common image of green space as a dangerous hiding place for criminal activity which causes feelings of insecurity, the results suggest that green space generally enhances feelings of social safety. The results also suggest, however, that green space in the most urban areas is a matter of concern with respect to social safety.

Childhood Characteristics of Adolescent Inpatients with Early-Onset and Adolescent-Onset Disruptive Behavior

Childhood characteristics are associated with life-course-persistent antisocial behavior in epidemiological studies in general population samples. The present study examines this association in an inpatient sample. The purpose is to identify easily measurable childhood characteristics that may guide choice of treatment for adolescent psychiatric inpatients with severe disruptive behavior. Patients (N = 203) were divided into two groups with either early-onset (EO) or adolescent-onset (AO) disruptive behavior, based on ages at which professional care was used for disruptive behavior, referral to special education, and criminal offences. Both groups differed on several childhood characteristics. No gender differences in these characteristics were found. Logistic regression analysis indicated that individuals with grade retention in primary school, childhood impulsive behavior, and a history of physical abuse, had the highest probability of being member of the EO group. These characteristics are reasonably easy to identify, likely apply to other clinical samples as well, and may help clinicians to target their treatment