Wpływ składu kompozytu wapienno konopnego na jego właściwości mechaniczne i fizyczne

W pracy przeanalizowano wpływ składu kompozytu wapienno konopnego na kluczowe właściwości mechaniczne i fizyczne. Artykuł zawiera wyniki badań wytrzymałości na ściskanie, paroprzepuszczalności oraz przewodności cieplnej kompozytu w zależności od składu mieszanek. Mieszanki różniły się miedzy sobą składem spoiwa oraz proporcjami spoiwa do paździerzy konopnych. Uzyskane wyniki porównano z wynikami z innej literatury naukowej. Na tej podstawie sformułowano wnioski, że skład spoiwa ma drugorzędne znaczenie na analizowane właściwości fizyczne i mechaniczne kompozytu wapienno konopnego. W toku badań i analiz wyników wykazano, że kluczowy wpływ na właściwości kompozytu wapienno konopnego ma jego gęstość. Wykazano również, na zależy ona od proporcji spoiwa do kruszywa. Rodzaj zastosowanego spoiwa ma drugorzędne znaczenie dla właściwości materiału. Z tego powodu zaleca się stosować spoiwa jak najbardziej ekologiczne, takie jak metakaolin, aby wpływ materiału na środowisko był jak najniższy.The following work analyzes the effect of the composition of a hemp-lime composite on key mechanical and physical properties. The article contains results from testing the compressive strength, vapor permeability, and thermal conductivity of the composite, depending on the composition of the mix. The mixes differed from each other in binder composition and in the proportion of binder to hemp shives. The obtained results were compared with the results from other scientific literature. Based on this, conclusions were drawn that the binder composition is of secondary importance for the analyzed physical and mechanical properties of the hemp-lime composite. The main property that determines the values of the thermal conductivity coefficient as well as the compression strength is the density of the material, which depends on the proportion of binder to aggregate and the level of compaction of the mix. The value of the diffusion resistance coefficient of the analyzed material was very low regardless of the composition of the composite

Hormonal determinants of the severity of andropausal and depressive symptoms in middle-aged and elderly men with prediabetes

Michał Rabijewski,1 Lucyna Papierska,2 Roman Kuczerowski,1 Paweł Piątkiewicz11Department of Internal Diseases, Diabetology and Endocrinology, Medical University of Warsaw, 2Department of Endocrinology, Medical Centre for Postgraduate Education, Warsaw, PolandAbstract: Andropausal and depressive symptoms are common in aging males and may be associated with hormone deficiency. We investigated the severity of andropausal and depressive symptoms, as well as their hormonal determinants, in 196 middle-aged and elderly men (age range: 40–80 years) with prediabetes (PD) and in 184 healthy peers. PD was diagnosed according to the definition of the American Diabetes Association. The severity of andropausal and depressive symptoms was assessed using the Aging Males’ Symptoms Rating Scale and the Self-Rating Depression Scale. Total testosterone (TT), calculated free testosterone (cFT), dehydroepiandrosterone sulfate (DHEAS), and insulin-like growth factor 1 (IGF-1) were measured. The prevalence of andropausal syndrome in men with PD was significantly higher than that in healthy men (35% vs 11%, respectively). In men with PD aged 40–59 years, the severity of sexual, psychological, and all andropausal symptoms was greater than in healthy peers, while in elderly men (60–80 years), only the severity of psychological symptoms was greater than in healthy peers. The severity of depressive symptoms in the middle-aged men with PD was greater than in healthy peers, while the severity of depressive symptoms in elderly men with PD and healthy peers was similar. The higher prevalence of andropausal symptoms was independently associated with cFT and IGF-1 in middle-aged men and with TT and DHEAS in elderly men with PD. The more severe depression symptoms were associated with low TT and DHEAS in middle-aged men and with low cFT and DHEAS in elderly men with PD. In conclusion, the prevalence of andropausal symptoms, especially psychological, was higher in prediabetic patients as compared to healthy men, while the severity of depressive symptoms was higher only in middle-aged men with PD. Hormonal determinants of andropausal and depressive symptoms are different in middle-aged and elderly patients, but endocrine tests are necessary in all men with PD.Keywords: prediabetes, andropausal symptoms, depression, testosterone, DHEAS, IGF-

Retinal Photoreceptors and Microvascular Changes in Prediabetes Measured with Adaptive Optics (rtx1™): A Case-Control Study

Background. Patients with prediabetes are at risk for diabetes, cardiovascular events, and microvascular complications. The rtx1 (Imagine Eyes, France) permits early detection of changes in the retinal photoreceptors and vessels. Objective. Cone parameters and retinal microvasculature were analyzed with the rtx1 in 12 prediabetic patients and 22 healthy subjects. The analysis was based on cone density (DM), interphotoreceptor distance (SM), cone packing regularity, and retinal vessel parameters: wall thickness, lumen diameter (LD), wall-to-lumen ratio (WLR), and cross-sectional area of the vascular wall. Results. DM in the prediabetic group was not significantly lower than that in the control group (18,935 ± 1713 cells/mm2 and 19,900 ± 2375 cells/mm2, respectively; p=0.0928). The LD and WLR means differed significantly between the prediabetic and the control groups (LD 94.3 ± 10.9 versus 101.2 ± 15, p=0.022; WLR 0.29 ± 0.05 versus 0.22 ± 0.03, p<0.05). A multivariate regression analysis showed that the WLR was significantly correlated with BMI and total cholesterol. Conclusions. Abnormalities found in rtx1 examinations indicated early signs of arteriolar dysfunction, prior to impaired glucose tolerance progressing to diabetes. The rtx1 retinal image analysis offers noninvasive measurement of early changes in the vasculature that routine clinical examination cannot detect