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Depression has been associated with subclinical hypothyroidism and altered hypothalamic-pituitary-thyroid axis functioning. Adequate iodine nutrition is essential for healthy thyroid functioning. We therefore determined associations of iodine and thyroid status with paediatric major depressive disorder (pMDD) among Swiss adolescents and explored whether associations are sex-specific and mediated by stress. We conducted a matched case–control study in 95 adolescents with diagnosed pMDD and 95 healthy controls. We assessed depression severity using the Children’s Depression Rating Scale-Revised and stress using the perceived stress scale (PSS) and measuring hair cortisol levels. We determined iodine status by measuring urinary iodine concentrations (UIC) and thyroid status by thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in serum. Median (IQR) UIC did not differ between cases (121 (87, 174) µg/l) and controls (114 (66, 183) μg/l, P = 0·3). Median TSH and FT4 were lower in cases than controls (TSH: 1·36 (0·91, 2·00) mlU/l v. 1·50 (1·18, 2·06) mlU/l, P = 0·039; FT4: 14·7 (12·9, 16·9) pmol/l v. 15·7 (14·3, 17·2) pmol/l, P = 0·004). The prevalence of hypothyroxinaemia (normal TSH; low FT4) was higher among female cases than controls (21 % v. 4%, P = 0·006). PSS scores were higher while hair cortisol was lower in cases than controls (PSS: 25 (20, 28) v. 11 (7, 15), P < 0·001; cortisol: 2·50 (1·34, 3·57) pg/mg v. 3·23 (1·79, 4·43) pg/mg, P = 0·044). After adjusting for confounders, the associations of TSH and hair cortisol with pMDD were no longer significant. Furthermore, TSH and FT4 were not associated with PSS scores and hair cortisol levels. Summarising, iodine nutrition was adequate for adolescents with and without pMDD. However, FT4 concentrations were lower in those with pMDD, and 1 in 5 female adolescents with pMDD were hypothyroxinaemic.
Diagnostic criteria for major depressive disorder allow for heterogeneous symptom profiles but genetic analysis of major depressive symptoms has the potential to identify clinical and etiological subtypes. There are several challenges to integrating symptom data from genetically informative cohorts, such as sample size differences between clinical and community cohorts and various patterns of missing data.
Methods
We conducted genome-wide association studies of major depressive symptoms in three cohorts that were enriched for participants with a diagnosis of depression (Psychiatric Genomics Consortium, Australian Genetics of Depression Study, Generation Scotland) and three community cohorts who were not recruited on the basis of diagnosis (Avon Longitudinal Study of Parents and Children, Estonian Biobank, and UK Biobank). We fit a series of confirmatory factor models with factors that accounted for how symptom data was sampled and then compared alternative models with different symptom factors.
Results
The best fitting model had a distinct factor for Appetite/Weight symptoms and an additional measurement factor that accounted for the skip-structure in community cohorts (use of Depression and Anhedonia as gating symptoms).
Conclusion
The results show the importance of assessing the directionality of symptoms (such as hypersomnia versus insomnia) and of accounting for study and measurement design when meta-analyzing genetic association data.
Deep reinforcement learning (DRL) is promising for solving control problems in fluid mechanics, but it is a new field with many open questions. Possibilities are numerous and guidelines are rare concerning the choice of algorithms or best formulations for a given problem. Besides, DRL algorithms learn a control policy by collecting samples from an environment, which may be very costly when used with Computational Fluid Dynamics (CFD) solvers. Algorithms must therefore minimize the number of samples required for learning (sample efficiency) and generate a usable policy from each training (reliability). This paper aims to (a) evaluate three existing algorithms (DDPG, TD3, and SAC) on a fluid mechanics problem with respect to reliability and sample efficiency across a range of training configurations, (b) establish a fluid mechanics benchmark of increasing data collection cost, and (c) provide practical guidelines and insights for the fluid dynamics practitioner. The benchmark consists in controlling an airfoil to reach a target. The problem is solved with either a low-cost low-order model or with a high-fidelity CFD approach. The study found that DDPG and TD3 have learning stability issues highly dependent on DRL hyperparameters and reward formulation, requiring therefore significant tuning. In contrast, SAC is shown to be both reliable and sample efficient across a wide range of parameter setups, making it well suited to solve fluid mechanics problems and set up new cases without tremendous effort. In particular, SAC is resistant to small replay buffers, which could be critical if full-flow fields were to be stored.
Thrombocytopenia is a risk factor for patent ductus arteriosus. Immature and mature platelets exhibit distinct haemostatic properties; however, whether platelet maturity plays a role in postnatal, ductus arteriosus closure is unknown.
Methods:
In this observational study, counts of immature and mature platelets (=total platelet count − immature platelet count) were assessed on days 1, 3, and 7 of life in very low birth weight infants (<1500 g birth weight). We performed echocardiographic screening for haemodynamically significant patent ductus arteriosus on day 7.
Results:
Counts of mature platelets did not differ on day 1 in infants with (n = 24) and without (n = 45) haemodynamically significant patent ductus arteriosus, while infants with significant patent ductus arteriosus exhibited lower counts of mature platelet on postnatal days 3 and 7. Relative counts of immature platelets (fraction, in %) were higher in infants with patent ductus arteriosus on day 7 but not on days 1 and 3. Receiver operating characteristic curve analysis unraveled associations between both lower mature platelet counts and higher immature platelet fraction (percentage) values on days 3 and 7, with haemodynamically significant ductus arteriosus. Logistic regression analysis revealed that mature platelet counts, but not immature platelet fraction values, were independent predictors of haemodynamically significant patent ductus arteriosus.
Conclusion:
During the first week of postnatal life, lower counts of mature platelets and higher immature platelet fraction values are associated with haemodynamically significant patent ductus arteriosus. Lower counts of mature platelet were found to be independent predictors of haemodynamically significant patent ductus arteriosus.
Somatic symptoms and anxiety symptoms are often disregarded in the detection of depression in primary care. The present investigation examined to what extent somatic and anxiety symptoms recorded with the Composite International Diagnostic Interview—Primary Health Care Version (CIDI—PHC) can improve the detection of depression as compared to the General Health Questionnaire—12-item version alone. Data from the World Health Organization study on Psychological Problems in General Health Care were used. The study sample consisted of primary care attenders from 15 centres from all over the world who underwent a psychiatric examination with the CIDI—PHC. Medically unexplained somatic symptoms (back pain, feelings of heaviness/lightness in parts of the body, periods of bodily weakness, seizures/convulsions, permanent tiredness, exhaustion after a minimum of effort) and—to a smaller extent—diverse anxiety symptoms (e.g. feelings of anxiousness/nervousness, feelings of tension, difficulties relaxing) significantly contributed to the detection of depression in a logistic regression analysis. The results confirm the observation that in primary care somatic symptoms play an important role in the manifestation of depressive disorders. The items investigated herein could prove beneficial for future depression screening instruments to improve the detection of depressive disorders in primary care.
Pulmonary hypertension is a complex and progressive condition that is either idiopathic or heritable, or associated with one or multiple health conditions, with or without congenital or acquired cardiovascular disease. Recent developments have tremendously increased the armamentarium of diagnostic and therapeutic approaches in children and young adults with pulmonary hypertension that is still associated with a high morbidity and mortality. These modalities include non-invasive imaging, pharmacotherapy, interventional and surgical procedures, and supportive measures. The optimal, tailored diagnostic and therapeutic strategies for pulmonary hypertension in the young are rapidly evolving but still face enormous challenges: Healthcare providers need to take the patient’s age, development, disease state, and family concerns into account when initiating advanced diagnostics and treatment. Therefore, there is a need for guidance on core and advanced medical training in paediatric pulmonary hypertension. The Association for European Paediatric and Congenital Cardiology working group “pulmonary hypertension, heart failure and transplantation” has produced this document as an expert consensus statement; however, all recommendations must be considered and applied in the context of the local and national infrastructure and legal regulations.
Despite the environmental stresses that mangrove forests experience – including fluctuating salinity, low soil oxygen and buffeting by waves – they can be highly productive. Facilitation, defined here as the benefits to an organism by the minimisation by neighbouring organisms of biotic or physical stress, may help explain this. Theory suggests that facilitation is likely in stressful environments, and trees and shrubs have been found to be particularly likely to exhibit facilitation. Hence, we should find facilitation in mangrove forests, and this chapter summarises new and published evidence for its existence. Facilitation occurs at a wide range of scales and during all different points in a mangrove tree's life. Amelioration of hydrodynamic and dessicative stresses can be important during seedling establishment and early growth. Interactions with fauna, including crabs and ants, can sustain tree production and help defend against herbivores. Ecosystem-scale facilitation helps ensure resilience in the face of changes such as sea-level rise. Hence facilitation is common in mangroves, and the challenge now is to gain a theoretical understanding of when and where to expect it.
Background: Atrial fibrillation (AF) is a cause of ischemic stroke and is associated with recurrence and with acute multi-vessel territory non lacunar stroke. Many cryptogenic strokes could be secondary to undiagnosed paroxystic AF. As left atrium (LA) dilatation is a risk factor of AF, we sought to determine if moderate or severe LA dilatation was associated with multiple vascular territory infarcts on magnetic resonance imaging (MRI) in patients with acute ischemic stroke without known AF. Normal LA diameter values are ≤4.0 cm for men and ≤3.8 for women. Methods: Patients who presented at our center between 2006 and 2011 with a diagnosis of acute ischemic stroke (AIS) or transient ischemick attack (TIA) who had a transthoracic echocardiography and a brain MRI were included. Patients with known or de novo AF diagnosed within 3 months of the event were excluded. The main outcome was the presence of acute multi-vessel territory infarct(s) on MRI.Results: 356 patients were included. The mean LA diameter was 37 mm in the control group (normal or mildly dilated LA) and 49 mm in those with moderately to severely enlarged LA (p<0.001). More patients in the LA dilatation group met the main outcome (20% vs 6%; OR 3.89; 95% CI 1.32-11.43; p=0.0014). Conclusions: LA dilatation (at least moderate) is associated with acute non lacunar multiple vascular territory infarcts on MRI in patients with AIS or TIA without known AF or a confirmed diagnosis of AF. Further studies are necessary to determine if this population might benefit from anticoagulation therapy.
We present a compositional programme logic for call-by-value imperative higher-order functions with general forms of aliasing, which can arise from the use of reference names as function parameters, return values, content of references and parts of data structures. The programme logic extends our earlier logic for alias-free imperative higher-order functions with new operators which serve as building blocks for clean structural reasoning about programms and data structures in the presence of aliasing. This has been an open issue since the pioneering work by Cartwright–Oppen and Morris twenty-five years ago. We illustrate usage of the logic for description and reasoning through concrete examples including a higher-order polymorphic Quicksort. The logical status of the new operators is clarified by translating them into (in)equalities of reference names.
Adherence to treatment guidelines enhances treatment outcome. However, in clinical practice many patients with depression do not receive appropriate treatment.
Aims
To evaluate the treatment of depression in in-patients of German psychiatric hospitals with respect to treatment outcome and adherence to guidelines.
Method
We recruited 1202 in-patients with depression from ten different hospitals. Quality data concerning treatment were collected at admission, during the treatment course and at discharge.
Results
The level of depression was significantly decreased and most patients were satisfied with treatment. Many aspects of the treatment routine adhered to guideline recommendations. Adherence to guidelines could be improved with respect to adjustment of antidepressant dosage, reduction of benzodiazepine prescription, enhanced use of electroconvulsive therapy and wider use of interpersonal therapy.
Conclusions
The study reveals a high standard of psychiatric treatment of in-patients with depression. Nevertheless there is still room for improvement. Differences between hospitals in adherence to guidelines indicates the need for individual application of quality management tools.
A menudo, se hace caso omiso de los smtomas somáticos y los síntomas de ansiedad en la detección de la depresión en atencion primaria. La presente investigacion examinó en qué medida los síntomas somáticos y de ansiedad registrados en la Entrevista Diagnostica Internacional Compuesta-Version de Atención Primaria (CIDI-PHC) pueden mejorar la detección de la depresión comparado con el Cuestionario de Salud General, versión de 12 elementos, solo. Se utilizaron datos del estudio de la Organización Mundial de la Salud sobre Problemas Psicológicos en Atención Sanitaria General. La muestra de estudio constaba de las personas que acudieron a los servicios de atención primaria de 15 centros de todo el mundo y se sometieron a un examen psiquiátrico con la CIDI-PHC. Los smtomas somáticos sin explicación médica (dolor de espalda, sensaciones de pesadez/ligereza en partes del cuerpo, períodos de debilidad corporal, crisis/convulsiones, cansancio permanente, agotamiento después de un esfuerzo mínimo) y -en menor medidasíntomas de ansiedad diversos (p. ej., sentimientos de ansiedad/nerviosismo, sentimientos de tensión, dificultades para relajarse) contribuyeron significativamente a la detección de la depresión en un análisis de regresión logística. Los resultados confirman la observación de que, en la atención primaria, los síntomas somáticos desempefian un papel importante en la manifestacion de los trastornos depresivos. Los elementos investigados aquí podrían resultar beneficiosos para que futuros instrumentos de deteccion selectiva de la depresivos en la atención primaria.
The oil palm (Elaeis guineensis) is a native of West Africa. It flourishes in the humid tropics in groves of varying density, mainly in the coastal belt between 10 degrees north latitude and 10 degrees south latitude. It is also found up to 20 degrees south latitude in Central and East Africa and Madagascar in isolated localities with a suitable rainfall. It grows on relatively open ground and, therefore, originally spread along the banks of rivers and later on land cleared by humans for long-fallow cultivation (Hartley 1988: 5–7).
The palm fruit develops in dense bunches weighing 10 kilograms (kg) or more and containing more than a thousand individual fruits similar in size to a small plum. Palm oil is obtained from the flesh of the fruit and probably formed part of the food supply of the indigenous populations long before recorded history. It may also have been traded overland, since archaeological evidence indicates that palm oil was most likely available in ancient Egypt. The excavation of an early tomb at Abydos, dated to 3000 B.C., yielded “a mass of several Kilograms still in the shape of the vessel which contained it” (Friedel 1897).
A sample of the tomb material was submitted to careful chemical analysis and found to consist mainly of palmitic acid, glycerol in the combined and free state, and a mixture of azelaic and pimelic acids. The latter compounds are normal oxidation products of fatty acids, and the analyst concluded that the original material was probably palm oil, partly hydrolyzed and oxidized during its long storage.