173 research outputs found
The Henstock-Kurzweil-Pettis integrals and existence theorems for the Cauchy problem
summary:In this paper we prove an existence theorem for the Cauchy problem using the Henstock-Kurzweil-Pettis integral and its properties. The requirements on the function are not too restrictive: scalar measurability and weak sequential continuity with respect to the second variable. Moreover, we suppose that the function satisfies some conditions expressed in terms of measures of weak noncompactness
Nonlinear fractional differential equations in nonreflexive Banach spaces and fractional calculus
The aim of this paper is to correct some ambiguities and inaccuracies in Agarwal et al. (Commun. Nonlinear Sci. Numer. Simul. 20(1): 59-73, 2015; Adv. Differ. Equ. 2013: 302, 2013, doi:10.1186/1687-1847-2013-302) and to present new ideas and approaches for fractional calculus and fractional differential equations in nonreflexive Banach spaces
Effects of Low Carbohydrate High Protein (LCHP) diet on atherosclerotic plaque phenotype in mice : FT-IR and Raman imaging
Low Carbohydrate High Protein (LCHP) diet displays pro-atherogenic effects, however, the exact mechanisms involved are still unclear. Here, with the use of vibrational imaging, such as Fourier transform infrared (FT-IR) and Raman (RS) spectroscopies, we characterize biochemical content of plaques in Brachiocephalic Arteries (BCA) from ApoE/LDLR−/− mice fed LCHP diet as compared to control, recomended by American Institute of Nutrition, AIN diet. FT-IR images were taken from 6–10 sections of BCA from each mice and were complemented with RS measurements with higher spatial resolution of chosen areas of plaque sections. In aortic plaques from LCHP fed ApoE/LDLR−/− mice, the content of cholesterol and cholesterol esters was increased, while that of proteins was decreased as evidenced by global FT-IR analysis. High resolution imaging by RS identified necrotic core/foam cells, lipids (including cholesterol crystals), calcium mineralization and fibrous cap. The decreased relative thickness of the outer fibrous cap and the presence of buried caps were prominent features of the plaques in ApoE/LDLR−/− mice fed LCHP diet. In conclusion, FT-IR and Raman-based imaging provided a complementary insight into the biochemical composition of the plaque suggesting that LCHP diet increased plaque cholesterol and cholesterol esters contents of atherosclerotic plaque, supporting the cholesterol-driven pathogenesis of LCHP–induced atherogenesis
Determinants of distribution and prevalence of avian malaria in blue tit populations across Europe : separating host and parasite effects
Although avian malarial parasites are globally distributed, the factors that affect the geographical distribution and local prevalence of different parasite lineages across host populations or species are still poorly understood. Based on the intense screening of avian malarial parasites in nine European blue tit populations, we studied whether distribution ranges as well as local adaptation, host specialization and phylogenetic relationships can determine the observed prevalences within populations. We found that prevalence differed consistently between parasite lineages and host populations, indicating that the transmission success of parasites is lineage specific but is partly shaped by locality-specific effects. We also found that the lineage-specific estimate of prevalence was related to the distribution range of parasites: lineages found in more host populations were generally more prevalent within these populations. Additionally, parasites with high prevalence that were also widely distributed among blue tit populations were also found to infect more host species. These findings suggest that parasites reaching high local prevalence can also realize wide distribution at a global scale that can have further consequences for host specialization. Although phylogenetic relationships among parasites did not predict prevalence, we detected a close match between a tree based on the geographic distance of the host populations and the parasite phylogenetic tree, implying that neighbouring host populations shared a related parasite fauna
People with diabetes need a lower cut-off than others for depression screening with PHQ-9
Aims: This study evaluated the psychometric characteristics of the Polish version of the PHQ-9 in detecting major depression (MDD) and ‘MDD and/or dysthymia’ in people with and without type 2 diabetes. Methods: Participants were randomly selected from a diabetes outpatient facility (N = 216) and from among patients admitted to a medical center and psychiatric hospital (N = 99). The participants completed the PHQ-9. The Hamilton Depression Rating Scale and the Mini International Neuropsychiatric Interview were used to identify the presence of psychiatric symptoms. The optimal cut-offs for PHQ-9 in people with and without type 2 diabetes were investigated based on two methods: 1) Youden’s index which identifies cut-off points useful in scientific research; 2) a second method of two-stage screening for depressive disorders to provide guidance for clinical practice. Results: The Polish version of the PHQ-9 is a reliable and valid screening tool for depression in people with and without type 2 diabetes. An optimal cut-off of ≥ 7 was indicated by Youden’s index and ≥ 5 by the two-stage method for screening for MDD and ‘MDD and/or dysthymia’ in the group with type 2 diabetes. A cut-off of ≥ 11 was optimal for screening for both MDD and ‘MDD and/or dysthymia’ among people without diabetes (Youden’s index). The two-stage approach suggested a ≥ 10 score for screening for MDD and ≥ 9 for screening for ‘MDD and/or dysthymia’ in people without diabetes. Conclusions: A lower cut-off score of the PHQ-9 is recommended for people with type 2 diabetes as compared to the general population
Effects of Interspecific Coexistence on Laying Date and Clutch Size in Two Closely Related Species of Hole-nesting Birds
Coexistence between great tits Parus major and blue tits Cyanistes caeruleus, but also other hole-nesting taxa, constitutes a classic example of species co-occurrence resulting in potential interference and exploitation competition for food and for breeding and roosting sites. However, the spatial and temporal variations in coexistence and its consequences for competition remain poorly understood. We used an extensive database on reproduction in nest boxes by great and blue tits based on 87 study plots across Europe and Northern Africa during 1957–2012 for a total of 19,075 great tit and 16,729 blue tit clutches to assess correlative evidence for a relationship between laying date and clutch size, respectively, and density consistent with effects of intraspecific and interspecific competition. In an initial set of analyses, we statistically controlled for a suite of site-specific variables. We found evidence for an effect of intraspecific competition on blue tit laying date (later laying at higher density) and clutch size (smaller clutch size at higher density), but no evidence of significant effects of intraspecific competition in great tits, nor effects of interspecific competition for either species. To further control for site-specific variation caused by a range of potentially confounding variables, we compared means and variances in laying date and clutch size of great and blue tits among three categories of difference in density between the two species. We exploited the fact that means and variances are generally positively correlated. If interspecific competition occurs, we predicted a reduction in mean and an increase in variance in clutch size in great tit and blue tit when density of heterospecifics is higher than the density of conspecifics, and for intraspecific competition, this reduction would occur when density of conspecifics is higher than the density of heterospecifics. Such comparisons of temporal patterns of means and variances revealed evidence, for both species, consistent with intraspecific competition and to a smaller extent with interspecific competition. These findings suggest that competition associated with reproductive behaviour between blue and great tits is widespread, but also varies across large spatial and temporal scales. © 2018 The Authors. Journal of Animal EcologyAcademy of Finland 26585
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PAID-PL—The Polish Version of the Problem Areas in Diabetes Scale: Perfect Reliability and a One-Factor Structure
Purpose: The aim of this study was to assess the structure and validate the Polish version of the Problem Areas in Diabetes (PAID) scale, as the current translations of the original English version significantly vary in their psychometric properties.
Patients and Methods: Two hundred and sixteen consecutive Polish outpatients were invited to participate in this international cross-sectional study on depression in diabetes. The research was based on the demographic and clinical characteristics of the study population, including the level of glycated hemoglobin (HbA1c) and scores obtained in the Polish versions of the following questionnaires: PAID, World Health Organization-Five Well-Being Index (WHO-5), Patient Health Questionnaire 9 (PHQ-9). The psychiatric diagnosis was conducted with the use of Mini-International Neuropsychiatric Interview (M.I.N.I.).
Results: Exploratory factor analyses yielded a 1-factor structure that included all 20 items. The internal consistency of the Polish version of PAID was high (Cronbach α = 0.97). There were significant positive correlation between PAID and PHQ-9 and a negative correlation between PAID and WHO-5. We also observed a negative association between PAID scores and age and a positive correlation between PAID and HbA1c levels. Patients with depression reported significantly higher PAID scores as compared with those without depressive symptoms.
Conclusion: The Polish version of PAID has a one-factor structure and is a reliable, valid outcome measure for Polish outpatients with type 2 diabetes and it may constitute a useful instrument for screening for psychologic issues in diabetic patients during their appointments at the diabetes clinic
Positive left atrial remodeling in patients with paroxysmal atrial fibrillation after a successful radiofrequency pulmonary vein isolation
Background: The potential relationship between the initial left atrial (LA) echocardiographic parameters and LA remodeling after pulmonary vein isolation with RF energy (PVI) with effectiveness of this treatment is discussed.
Aim: To determine the influence of initial and after follow-up transthoracic echocardiography derived predictors of successful PVI in patients with paroxysmal atrial fibrillation (AF).
Methods: 80 patients with paroxysmal AF (58 [interquartile range, IQR], 50–63] years, males: 58 [IQR, 50–63]), hospitalized for the first time PVI procedure were included. Before and after a minimum of 6 months of follow-up period a clinical and echocardiographic evaluation were performed. LA morphological parameters (diameter, volumes and other detailed LA parameters), as well as LA peak segmental and global longitudinal strains (PLS) and LA wall strain synchrony were assessed.
Results: In the whole group after a follow-up period, patients presented higher mean LA Volconduit. Patients with no AF recurrences had lower post-PVI LA volumes, higher LA ejection fraction and LA expansion index, when compared to the patients after ineffective PVI. Patients who maintained sinus rhythm after PVI procedure were characterized by a higher initial segmental strains: LA PLSbasal-inferior and PLSapical-septal, as well as higher LA wall strain dispersion in time.
Conclusions: Some echocardiographic parameters related to LA morphology improve after successful PVI treatment. LA strains and wall strain dispersion in time are not related to LA remodeling after successful PVI procedure. However the baseline LA standard and novel echocardiographic parameters cannot be used as a remote evaluation of the effectiveness of the PVI procedure
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