314 research outputs found

    Uncovering predictability in the evolution of the WTI oil futures curve

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    Accurately forecasting the price of oil, the world's most actively traded commodity, is of great importance to both academics and practitioners. We contribute by proposing a functional time series based method to model and forecast oil futures. Our approach boasts a number of theoretical and practical advantages including effectively exploiting underlying process dynamics missed by classical discrete approaches. We evaluate the finite-sample performance against established benchmarks using a model confidence set test. A realistic out-of-sample exercise provides strong support for the adoption of our approach with it residing in the superior set of models in all considered instances.Comment: 28 pages, 4 figures, to appear in European Financial Managemen

    Adjustment disorder, traumatic stress, depression and anxiety in Poland during an early phase of the COVID-19 pandemic

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    Background: The current COVID-19 pandemic is associated with a variety of stressors. Preliminary research has demonstrated that general public are experiencing a range of psychological problems, including stress-related disturbances. However, to date, there is not much research on the prevalence of adjustment disorder during the current pandemic. Objectives: This study aimed to assess the prevalence and severity of symptoms of adjustment disorder compared to posttraumatic symptoms, depression and generalized anxiety in a large sample of adult Poles, in the first phase of the current pandemic. Method: Self-report data from a web-based sample (N = 1,742) was collected between March 25 and April 27, just after the introduction of nationwide quarantine measures in Poland. Results: The current COVID-19 pandemic was a highly stressful event for 75% of participants and the strongest predictor of adjustment disorder. Increased symptoms of adjustment disorder were reported by 49%, and they were associated with female gender and not having a full-time job. However, after exclusion of co-occurring symptomatology, 14% of the sample were finally qualified as meeting diagnostic criteria of adjustment disorder. A substantial proportion of the sample screened also positive for generalized anxiety (44%) and depression (26%); the rate for presumptive PTSD diagnosis was 2.4%. Conclusions: High rates of negative mental health outcomes were found in the Polish population in the first weeks into the COVID-19 pandemic and lockdown measures. They indicate the intense current stress-related symptoms in the early phase of the pandemic and warrant further monitoring on population’s mental health

    20 Typ z przewagą limfocytów ziarnicy złośliwej: Czy wymaga odmiennego leczenia?

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    WstępTyp z przewagą limfocytów ziarnicy złośliwej (LP-HD) jest wyróżniany jako odrębna postać histokliniczna. Ponadto wykazuje się duże morfologiczne podobieństwo do chłoniaka nieziarniczego z limfocytów B, który w rozpoznaniach LP-HD LP-HD może stanowić do 10%. Celem pracy jest ocena przebiegu klinicznego i wyniki leczenia chorych na LP-HD.MateriałW Krakowskim Centrum Onkologii w latach 1987–1996 leczono 53 chorych z rozpoznaniem LP-HD, 14 kobiet i 39 mężczyzn (M:K – 2,8:1). Wiek chorych wahał się od 14 do 73 lat, mediana 39 lat. W stopniu zaawansowania I+II było 31 chorych (58,5%), III+IV 22 chorych (41,5%). Objawy B stwierdzono u 13/53 chorych (24,5%), X 10/53 chorych (18,8%), E u 2/53 chorych (3,8%). U 2/31 chorych (6,5%) proces był zlokalizowany w układzie chłonnym przedprzeponowym. W grupie I+II, 1 chory był leczony wyłącznie chemicznie (CHT), 22 chorych leczono wyłącznie CHT, 3 chorych RT i 10 chorych CHT+RT. Czas obserwacji waha się od 16 do 132 miesięcy (mediana 66 miesięcy).WynikiW całej grupie uzyskano 78% 5 – letnich i 71% 10 – letnich przeżyć, w grupie I+II odpowiednio 90% i 78%. W grupie III+IV 5 i 10 – letnie przeżycia wyniosły 62%. Całkowitą regresję po I rzucie leczenia uzyskano u 100% chorych w grupie I+II 4/5 wznów (80%) stwierdzono w układzie chłonnym przedprzeponowym. Czas wystąpienia wznowy wahał się od 14 do 712 miesięcy (mediana 41 miesięcy). U jednego chorego stwierdzono transformację typu LP w LD.U 3/53 chorych (5,6%) stwierdzono w kontroli chłoniaka nieziarniczego (MALT żołądka, nieokreślony chłoniak o wysokim stopniu złośliwości, chłoniak z limfocytów T) w okresie od 13 do 35 miesięcy (mediana 28 miesięcy). W grupie III+IV przeżycie 5 – letnie wyniosło 69% u chorych leczonych CHT i 32% leczonych wyłącznie RT (p = 0,3).Wnioski1.Wyniki leczenia chorych na LP-HD w naszym materiale nie odbiegają od wyników leczenia chorych na klasyczną postać ziarnicy. Ograniczenie zakresu RT w grupie I+II i CHT w grupie III+IV może mieć wpły na pogorszenie wyników leczenia.2.Mimo odrębności morfologicznych typ LP-HD powinien być leczony jak klasyczna postać ziarnicy złośliwej

    The bidirectional longitudinal association between depressive symptoms and HbA 1c : a systematic review and meta‐analysis

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    Aim To investigate whether there is a bidirectional longitudinal association of depression with HbA1c. Methods We conducted a systematic literature search in PubMed, PsycINFO, CINAHL and EMBASE for observational, longitudinal studies published from January 2000 to September 2020, assessing the association between depression and HbA1c in adults. We assessed study quality with the Newcastle-Ottawa-Scale. Pooled effect estimates were reported as partial correlation coefficients (rp) or odds ratios (OR). Results We retrieved 1,642 studies; 26 studies were included in the systematic review and eleven in the meta-analysis. Most studies (16/26) focused on type 2 diabetes. Study quality was rated as good (n=19), fair (n=2) and poor (n=5). Of the meta-analysed studies, six investigated the longitudinal association between self-reported depressive symptoms and HbA1c and five the reverse longitudinal association, with a combined sample size of n=48,793 and a mean follow-up of 2 years. Higher levels of baseline depressive symptoms were associated with subsequent higher levels of HbA1c (partial r=0.07;[95%CI0.03,0.12]; I238%). Higher baseline HbA1c values were also associated with 18% increased risk of (probable) depression (OR=1.18;[95%CI1.12,1.25]; I20.0%). Conclusions Our findings support a bidirectional longitudinal association between depressive symptoms and HbA1c. However, the observed effect sizes were small and future research in large-scale longitudinal studies is needed to confirm this association. Future studies should investigate the role of type of diabetes and depression, diabetes distress and diabetes self-management behaviours. Our results may have clinical implications, as depressive symptoms and HbA1c levels could be targeted concurrently in the prevention and treatment of diabetes and depression

    Longitudinal associations between depression and diabetes complications: a systematic review and meta-analysis

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    Aims. To conduct a systematic review and meta-analysis of longitudinal studies assessing the bi- directional association between depression and diabetes macrovascular and microvascular complications. Methods. Embase, Medline, and PsycINFO databases were searched from inception through 27th November 2017. A total of 4,592 abstracts were screened for eligibility. Meta-analyses used multilevel random/mixed-effects models. Quality was assessed using the Newcastle-Ottawa scale. Results. 22 studies were included in the systematic review. 16 studies examined the relationship between baseline depression and incident diabetes complications, of which nine studies involving over 1 million participants were suitable for meta-analysis. Depression was associated with an increased risk for incident macrovascular (Hazard Ratio HR=1.38; 95%CI: 1.30-1.47) and microvascular disease (HR=1.33; 95%CI: 1.25-1.41). Six studies examined the association between baseline diabetes complications and subsequent depression, of which two involving over 230 000 participants were suitable for meta-analysis. The results showed that diabetes complications increased the risk of incident depressive disorder (HR=1.14; 95%CI: 1.07-1.21). The quality analysis showed increased risk of bias notably in the representativeness of selected cohorts and ascertainment of exposure and outcome. Conclusions. Depression in people with diabetes is associated with an increased risk of incident macrovascular and microvascular complications. The relationship between depression and diabetes complications appears bi-directional. However, the risk of developing diabetes complications in depressed people is higher than the risk of developing depression in people with diabetes complications. The underlying mechanisms warrant further research

    Statistical Modeling of Solar Flare Activity from Empirical Time Series of Soft X-ray Solar Emission

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    A time series of soft X-ray emission observed on 1974-2007 years (GOES) is analyzed. We show that in the periods of high solar activity 1977-1981, 1988-1992, 1999-2003 the energy statistics of soft X-ray solar flares for class M and C is well described by a FARIMA time series with Pareto innovations. The model is characterized by two effects. One of them is a long-range dependence (long-term memory), and another corresponds to heavy-tailed distributions. Their parameters are statistically stable enough during the periods. However, when the solar activity tends to minimum, they change essentially. We discuss possible causes of this evolution and suggest a statistical model for predicting the flare energy statistics.Comment: 21 pages, 7 figure

    Prevalence and correlates of depressive disorders in people with Type 2 diabetes: results from the International Prevalence and Treatment of Diabetes and Depression (INTERPRET‐DD) study, a collaborative study carried out in 14 countries

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    Aims To assess the prevalence and management of depressive disorders in people with Type 2 diabetes in different countries. Methods People with diabetes aged 18–65 years and treated in outpatient settings were recruited in 14 countries and underwent a psychiatric interview. Participants completed the Patient Health Questionnaire and the Problem Areas in Diabetes scale. Demographic and medical record data were collected. Results A total of 2783 people with Type 2 diabetes (45.3% men, mean duration of diabetes 8.8 years) participated. Overall, 10.6% were diagnosed with current major depressive disorder and 17.0% reported moderate to severe levels of depressive symptomatology (Patient Health Questionnaire scores >9). Multivariable analyses showed that, after controlling for country, current major depressive disorder was significantly associated with gender (women) (PPPPP<0.0001). The proportion of those with either current major depressive disorder or moderate to severe levels of depressive symptomatology who had a diagnosis or any treatment for their depression recorded in their medical records was extremely low and non-existent in many countries (0–29.6%). Conclusions Our international study, the largest of this type ever undertaken, shows that people with diabetes frequently have depressive disorders and also significant levels of depressive symptoms. Our findings indicate that the identification and appropriate care for psychological and psychiatric problems is not the norm and suggest a lack of the comprehensive approach to diabetes management that is needed to improve clinical outcomes

    AR and MA representation of partial autocorrelation functions, with applications

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    We prove a representation of the partial autocorrelation function (PACF), or the Verblunsky coefficients, of a stationary process in terms of the AR and MA coefficients. We apply it to show the asymptotic behaviour of the PACF. We also propose a new definition of short and long memory in terms of the PACF.Comment: Published in Probability Theory and Related Field

    Short-form measures of diabetes-related emotional distress: The Problem Areas in Diabetes Scale (PAID)-5 and PAID-1

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    Aims/hypothesis: We wanted to identify a five-item short form of the Problem Areas in Diabetes Scale and a single-item measure for rapid screening of diabetes-related emotional distress. Methods: Using an existing database of 1,153 patients with diabetes, we conducted a principal-components analysis to identify a set of five items and then conducted a reliability analysis and validity checks. From those five items, we identified the item with the strongest psychometric properties as a one-item screening tool. Results: We identified a reliable and valid short version of the Problem Areas in Diabetes Scale (PAID) comprising five of the emotional-distress questions of the full PAID items (PAID-5, with items 3, 6, 12, 16, 19). The PAID-5 has satisfactory sensitivity (94%) and specificity (89%) for recognition of diabetes-related emotional distress. We also identified a one-item screening tool, the PAID-1 (Question 12: Worrying about the future and the possibility of serious complications), which has concurrent sensitivity and specificity of about 80% for the recognition of diabetes-related emotional distress. Conclusions/ interpretation: The PAID-5 and PAID-1 appear to be psychometrically robust short-form measures of diabetes-related emotional distress.Centro de Endocrinología Experimental y Aplicad
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