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Abstract  The simplest, yet robust, gradient elasticity theory (GRADELA) as first introduced by the last author is used to deduce nonsingular expressions for the stress and strain fields near dislocation lines and crack tips. These expressions are particularly useful for small volumes where the details of the deformation field need to be known for interpreting related experimental observations. Various implications are discussed in relation to the determination of the size of dislocation cores, the size of maximum stress or maximum strain in crack tips, and the interpretation of X-ray line profile measurements in determining internal stresses. [ABSTRACT FROM AUTHOR]

The aim of the present study was to examine whether the exercise intensity corresponding to the lactate threshold may be predicted by the Maximum Phonation Time task (MPT). Ten Greek amateur football players (age: 18.4 ± 1.0 years), performed a graded cycling exercise test to exhaustion in order to determine lactate threshold. A number of physiological variables were measured including perceived exertion, cardiopulmonary values and blood lactate. The MPT variable was correlated with all of the physiological variables. Also, a binary logistic regression analysis was used to investigate whether MPT could predict lactate threshold. The ROC analysis showed specificity to be 0.90 and sensitivity to be 0.70 (optimal screening cutoff point for MPT 9.5 seconds). The results showed an odds ratio of 1.45 indicating a 45% increase in the probability of passing the threshold for every second there was a reduction in voice duration. MPT may be used as a simple, non-invasive, inexpensive method for monitoring exercise intensity during physical exercise. Further research is needed to measure its efficacy in bigger samples and in different sports., (Copyright © 2021 The Voice Foundation. Published by Elsevier Inc. All rights reserved.)

Human activities are considered among the main producers of any kind of pollution. This paper, through a Driver-Pressure-State-Impact-Response (DPSIR) model analyses, focuses on the evaluation and assessment of the existing practices, procedures, and results obtained in order to determine whether the municipal solid waste (MSW) management implemented in three major Greek municipalities in the greater urban area of Attica, namely the municipalities of Nea Smirni, Vyronas, and Piraeus, could be considered viable and sustainable. The evaluation indicated that MSW in Greek cities have reduced over the last years, also suggesting a steady downward trend, which could be considered consistent with that of the per capita incomes in Greece due to the extended economic austerity, while at the same time the recycling indicator seems to optimize. The results are very useful for policymakers and local authorities towards taking actions related to the targets set from the circular economy strategies as well as the targets set from United Nation Development Program and the European Green Deal Strategy.

It is generally accepted that neuromuscular overload and fatigue of one lower limb can affect the functional ability of the ipsilateral limb, and possibly the contralateral limb, increasing the likelihood of injury. The purpose of the current study was to examine the effect of a unilateral countermovement vertical jump (UCVJ) fatigue protocol on the neuromuscular function of the ipsilateral as well as the contralateral lower limb. The isometric strength of the hip stabilizers, postural control via posturographic analysis during the Y-Balance-Test (YBT), and the stance-phase-of-gait were assessed in 24 healthy physical active males and females before and after execution of a UCVJ fatigue protocol. The fatigue protocol included 5 sets of 20 maximum UCVJs performed on the supportive leg, with a 30-s break between sets. Following a 16.8% decline in vertical jump performance and an associated 2.3-fold increase in perceived exertion, our findings revealed significant post-fatigue inter-limb differences regarding postural control. The post-fatigue inter-limb differences regarding the isometric strength of the hip stabilizers and the stance-phase-of-gait parameters were not significant. Our findings showed that a 100 UCVJs session is likely to induce significant inter-limb differences in postural control, possibly increasing the risk of lower limb injury.

It has been suggested that cytokine release during DKA may result in capillary perturbation and thus may contribute to the development of its acute clinical complications (i.e.cerebral or pulmonary edema). We studied in 38 newly diagnosed T1DM children with DKA, aged 7.68±3.07 years, plasma levels of cytokines IL-1β (interleukin-1β), IL-2, IL-6, IL-8, IL-10, TNF-α (tumour necrosis factor-α) and also WBC (white blood cell count), hs-CRP (high sensitivity C-reactive protein), GH (growth hormone) and cortisol, prior to, during and 120h after DKA management, with the aim to monitor their levels at different time-points and in different degrees of DKA severity. Prior to DKA management the levels of IL-6, IL-8, IL-10, WBC and cortisol were elevated, but were all reduced within 120 h after DKA management. Then the patients were divided into two groups: a. moderate/severe: pH≤7.2, b. mild DKA: pH>7.2. In the group with moderate/severe DKA (ph≤7.2), IL-10 levels were the highest of all cytokines, but were significantly decreased after 6h (91.76 vs 18.04 pg/mL, p=0.008), with no further change, while IL-6 levels were decreased at 120 h (28.32 vs 11.9 pg/mL, p=0.003). The above were not observed in the group with mild DKA. In conclusion, in the children with DKA of our study, in the group with moderate/severe DKA the IL-10 levels were prematurely reduced at 6 hours, while the IL-6 levels remained high and were reduced at 120 hours after the DKA management. These changes may be responsible for increased capillary perturbation, which could lead to the subsequent development of acute DKA complications.

Background/aims: Type 1 diabetes (T1DM) is associated with autoimmune thyroid, celiac, autoimmune gastric and Addison's disease. Our aim was to investigate the prevalence of associated autoantibodies in relation to the demographic and beta-cell autoantibody status (anti-GAD)., Methods: Antibodies against thyroid peroxidase (anti-TPO), thyroglobulin (anti-Tg), tissue transglutaminase (anti-tTG IgA), parietal cells (APCA) and adrenal tissue (AAA) were measured in 144 children with T1DM with a mean +/- SD age of 12.3 +/- 4.6 years and a diabetes duration of 4.6 +/- 3.8 years., Results: The prevalence of antibody positivity among our patients was: anti-GAD 53.2%, anti-thyroid (anti-TPO 17.4%, anti-Tg 11.1%); anti-tTG IgA 7.6%, APCA 4.0%, and AAA 0%. Among the children with positive anti-thyroid antibodies, 60% developed autoimmune thyroiditis, while among those anti-tTG IgA positive, 62.5% developed biopsy-confirmed celiac disease. Female gender was more frequent among anti-tTG IgA-positive patients (OR 4.47, p = 0.068), while increasing age was associated with anti-Tg positivity (OR 22.9, p = 0.041). The presence of anti-thyroid antibodies was associated with the presence of anti-GAD (OR 1.45, p = 0.01) and parietal cell antibodies (OR 4.98, p = 0.09)., Conclusion: Among T1DM patients, the prevalence rates of anti-thyroid and parietal cell antibodies increased with age and diabetes duration. As the presence of anti-GAD was associated with gastric and thyroid autoimmunity, it could serve as marker for the development of additional autoimmunity in adolescents with diabetes., (2009 S. Karger AG, Basel.)

The aim of the study was to assess the possible associations between allergies and type 1 diabetes mellitus (DM1), stratified by social class. We studied 127 children with DM1 with a median age of 10.8 yr and 150 controls of comparable age and sex distribution. The parents completed questionnaires on their education and occupation and on their children's history of allergic symptoms, breast-feeding, viral infections, and measles-mumps-rubella (MMR) vaccination. Lower family's social class was more frequently encountered among the DM1 families than in the controls (OR = 0.56, 95% CI: 0.35-0.92). The occurrence of any allergic symptoms among children with DM1 (35.45%) was not significantly different from the controls (38.78%), neither in the total group (OR = 0.87, 95% CI: 0.52-1.45) nor in the stratified analysis by social class. Similar findings were observed regarding the different types of allergic symptoms. In the univariate analysis, breast-feeding, the experience of viral infections, and MMR vaccination were found to be protective of DM1 presentation in both upper and lower social classes. In the multiple logistic regression analysis, the experience of more than 2 infections/yr (OR = 0.12, 95% CI: 0.04-0.34), the origin from middle and upper social classes (OR = 0.42, 95% CI: 0.22-0.80) and breast-feeding (OR = 0.58, 95% CI: 0.31-1.07) were protective of DM1 occurrence. In children with DM1, the presence of allergic symptoms was not associated with the development of DM1. Among the environmental factors, the origin from middle or upper social classes, breast-feeding, the experience of viral infections, and MMR vaccination were found to have a protective effect on DM1 presentation.

Diabetic cardiomyopathy is a well-defined complication of diabetes that occurs in the absence of ischemic heart disease or hypertension. Moreover impaired circadian blood pressure (BP) variation has been associated with autonomic dysfunction. The aim of our study was to evaluate diurnal BP fluctuations and autonomic function and their association with left ventricular function in adolescents with Type 1 diabetes mellitus (T1DM). In 48 normotensive, normoalbuminuric diabetic adolescents, with a mean (+/-SD) age of 17.3 (+/-4.1) yr and a mean (+/-SD) diabetes duration of 8.5 (+/-3.3) yr, 24-h ambulatory BP was recorded. Moreover 24-h heart rate (HR) monitoring was performed. Myocardial structural parameters were studied by echocardiogram. Left ventricular end-diastolic (EDDLV) and end-systolic diameters (ESDLV) were estimated and left ventricular mass index (LVMI) was calculated using the Devereux formula. The patients were divided into 2 groups according to the absence of decrease (non-dippers) or the decrease (dippers) of nocturnal diastolic BP (DBP). The non-dippers showed, in comparison with the dippers, reduced mean 24-h HR (79.6 vs 84.0 beats/min, p=0.05) and reduced mean day-time HR (81.3 vs 86.0 beats/min, p=0.05). The nondippers also presented greater ESDLV (28.7 vs 25.9 mm, p=0.001) and EDDLV (47.8 vs 45.1 mm, p=0.040), and LVMI (90.2 vs 78.3 g/m2, p=0.044), in comparison with the dippers. During stepwise multiple regression, the most important variables affecting LVMI were mean HR (day): (b=-0.40, p=0.001), high frequency domain variable of HR variability (b=0.38, p=0.016) and glycosylated hemoglobin (b=0.67, p=0.001). In conclusion, we found that a group of normotensive diabetic adolescents with impaired nocturnal BP reduction, also had autonomic dysfunction, together with impaired left ventricular function. These findings suggest that there is a close relationship between autonomic function and left ventricular remodeling in patients with T1DM, which may be attributed to altered diurnal BP profile, autonomic neuropathy and poor glycemic control.

Aims: The aim of our study was to assess diurnal blood pressure (BP) and heart rate variability and their possible relationship to the duration of the QT interval in adolescents with Type 1 diabetes., Methods: In 48 normotensive, normoalbuminuric diabetic adolescents, with a mean (+/- sd) age of 17.3 (+/- 4.1) years and a mean (+/- sd) diabetes duration of 8.5 (+/- 3.3) years, 24-h ambulatory BP was recorded. In addition, 24-h heart rate (HR) monitoring was performed and QT and corrected QT (QTc) intervals were estimated as indices of autonomic function. The patients were divided into two groups according to the absence of a decrease (non-dippers) or the presence of a decrease (dippers) in nocturnal diastolic BP (DBP)., Results: In comparison with the dippers, the non-dippers showed reduced mean 24-h HR (79.6 vs. 84.0 beats/min, P = 0.05) and reduced mean daytime HR (81.3 vs. 86.0 beats/min, P = 0.05). The QT interval was prolonged in the non-dippers (366.3 vs. 347.5 ms, P = 0.015), and end systolic (28.7 vs. 25.9 mm, P = 0.004) and end diastolic left ventricular diameters (47.8 vs. 45.5 mm, P = 0.037) were greater. In stepwise multiple regression, HR variables were the most important factors affecting DBP ratio or the duration of the QT interval., Conclusions: In conclusion, normotensive diabetic adolescents with impaired nocturnal BP reduction also have impaired autonomic function tests, in association with prolonged QT interval and increased left ventricular diameters. These findings suggest that diabetic adolescents who have the 'non-dipper' phenomenon may need close follow-up for the possible development of vascular complications, such as cardiac arrhythmias and left-ventricular hypertrophy.