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1.
Polymers (Basel) ; 16(15)2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39125208

ABSTRACT

Additive manufacturing (AM) technologies, including 3D mortar printing (3DMP), 3D concrete printing (3DCP), and Liquid Deposition Modeling (LDM), offer significant advantages in construction. They reduce project time, costs, and resource requirements while enabling free design possibilities and automating construction processes, thereby reducing workplace accidents. However, AM faces challenges in achieving superior mechanical performance compared to traditional methods due to poor interlayer bonding and material anisotropies. This study aims to enhance structural properties in AM constructions by embedding 3D-printed polymeric meshes in clay-based mortars. Clay-based materials are chosen for their environmental benefits. The study uses meshes with optimal geometry from the literature, printed with three widely used polymeric materials in 3D printing applications (PLA, ABS, and PETG). To reinforce the mechanical properties of the printed specimens, the meshes were strategically placed in the interlayer direction during the 3D printing process. The results show that the 3D-printed specimens with meshes have improved flexural strength, validating the successful integration of these reinforcements.

2.
Materials (Basel) ; 17(16)2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39203301

ABSTRACT

In the last decades, nano-silica (NS), nano-alumina (NA), and nano-calcium oxide (NC) particles have been incorporated into cementitious materials, and it seems that each one of them contributes uniquely to the materials' properties. This research explores the influence of each nanomaterial on the fresh properties of cement pastes and their compressive strength evolution over one year. Low proportions (1.5% by weight) of nanomaterials were added to cement pastes, and their fresh properties, such as heat of hydration and X-ray diffraction patterns in the first hours, were analyzed. The compressive strength and open porosity were also measured long-term. The acceleration of hydration heat in NA-cement pastes is linked to enhanced hydration product formation at early ages. Among the tested nanomaterials, NA increased compressive strength by 10% at later ages. Although the fresh properties of NC-cement pastes remained unaffected, their open porosity decreased by 54% at 28 days. In contrast, the increase in heat of hydration in NS-cement pastes did not result in significant strength improvement. Based on these findings, NA was selected for ultra-high-performance cement (UHPC)-based material use. Its incorporation not only preserved the ultra-high-performance (UHP) properties but also provided additional benefits such as an increase in compressive strength under a CO2 atmosphere. Through detailed analysis, this research establishes that nano-alumina incorporation optimizes the microstructural development and compressive strength of ultra-high-performance cement-based systems, presenting a novel advancement in enhancing the mechanical properties and durability of these materials under various environmental conditions.

3.
EXCLI J ; 22: 809-827, 2023.
Article in English | MEDLINE | ID: mdl-37780941

ABSTRACT

Zinc is a multipurpose trace element for the human body, as it plays a crucial part in various physiological processes, such as cell growth and development, metabolism, cognitive, reproductive, and immune system function. Its significance in human health is widely acknowledged, and this has led the scientific community towards more research that aims to uncover all of its beneficial properties, especially when compared to other essential metal ions. One notable area where zinc has shown beneficial effects is in the prevention and treatment of various diseases, including cancer. This review aims to explain the involvement of zinc in specific health conditions such as cancer, coronavirus disease 2019 (COVID-19) and neurological disorders like Alzheimer's disease, as well as its impact on the gut microbiome.

4.
Materials (Basel) ; 16(14)2023 Jul 11.
Article in English | MEDLINE | ID: mdl-37512213

ABSTRACT

The growing need to preserve natural resources and minimize landfill waste has led to an increased consideration of incorporating waste materials in road construction and maintenance. This study focuses specifically on utilizing waste glass as part of the aggregates in hot asphalt, particularly in Asphalt Concrete (AC) for surface layers, known as "Glassphalt". Glass, due to its poor adhesion to bitumen, presents challenges when used in asphalt mixtures. Two types of waste glass, monolithic and tempered, were incorporated at two distinct contents, 10% and 15%, into the AC. Several properties such as stiffness, resistance to permanent deformation (evaluated through cyclic compression tests), indirect tensile strength, and the indirect tensile strength ratio (ITSR) were assessed for all Glassphalt mixtures, as well as the conventional mixture. Additionally, the Solar Reflectance Index (SRI) was measured to evaluate the reflectivity of the resulting Glassphalts. The findings indicate that the incorporation of both types of waste glass resulted in reduced stiffness and resistance to permanent deformation. Regarding water sensitivity (ITSR), the Glassphalts containing 15% waste glass, regardless of the glass type, exhibited ITSR values below the accepted threshold of 80%. The addition of waste glass did not yield significant changes in SRI measurements.

5.
Med Pharm Rep ; 95(3): 267-274, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36060500

ABSTRACT

Aims: To identify to what extent stress and self-efficacy may be associated with specific features in the elderly with type 2 diabetes, such as lifestyle habits, multi-morbidity, sleep quality and duration, and treatment regimen. Methods: A cross-sectional study of 92 out of 103 recruited patients ≥65 year old with a diagnosis of type 2 diabetes was conducted at a rural primary care unit in Northern Greece. The General Self-Efficacy Scale (GSES), the Short Anxiety Screening Test (SAST) and an original questionnaire to assess health habits and disease monitoring information were completed after structured personal interviews. Results: In the multiple linear regression analysis, patients with higher education, with more night sleeping hours and physical exercise weekly had a higher GSES score than their counterparts (p<0.05). Stress levels assessed with SAST were shown mostly associated with poor sleep quality, fewer days of meat and legumes consumption, increased body mass index and multi-morbidity (p<0.05), as emerged from the multiple linear regression analysis. Glycemic control in the elderly does not have a significant correlation with stress levels or general self-efficacy. Conclusions: Self-efficacy and stress levels are not predictors for glycemic control, but can indirectly be seen as co-determinants, contributing to the overall daily life quality among patients with diabetes. Mental health well-being, expressed by higher self-efficacy and less stress scale rating, showed positive interferences with eating, sleep and daily life attitudes among elderly with diabetes.

6.
Surg Endosc ; 36(10): 7652-7655, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35182215

ABSTRACT

BACKGROUND: Patients' social support has been shown to impact outcomes after bariatric surgery. We have previously shown that a Facebook group administered by bariatric providers offers an effective alternative social support mechanism to in-person support groups, with higher patient participation. Our aim was to determine whether participation in this Facebook group could improve patient outcomes after bariatric surgery. METHODS: After institutional board approval, our center's Facebook group members were electronically surveyed about their perceived value of group participation and their Facebook group usage frequency. We also collected patient age, sex, insurance, preoperative weight, type of procedure, hospital stay, postoperative complications, and weight loss from the electronic medical record. To assess the impact of Facebook group participation we compared patient outcomes between "frequent users" (those checking the Facebook group's activity at least once a week), "infrequent users", and a control group of all patients operated on during the year prior to the establishment of the Facebook group. The groups were compared after adjusting for potential confounding factors. RESULTS: 250 out of 1400 Facebook group patients responded to the survey (18%). 195 patients were frequent and 55 were infrequent users. Outcomes were compared with 211 control patients. The groups did not differ in their baseline characteristics apart from their sex. Frequent users had a higher weight loss compared to the other groups up to 2 years postoperatively but no difference in the overall complications. On multivariable analysis, frequency of Facebook use was the main factor associated with 0.5-, 1-, and 2-year weight loss. CONCLUSION: Frequent participation in a Facebook support group after bariatric surgery was associated with improved early weight loss outcomes. If additional longer-term studies confirm our findings, offering similar social support groups may become essential after bariatric surgery, especially during times of social isolation when in-person social support meetings may not be feasible.


Subject(s)
Bariatric Surgery , Obesity, Morbid , Social Media , Humans , Obesity, Morbid/surgery , Social Support , Weight Loss
7.
Epilepsia ; 63(1): 237-243, 2022 01.
Article in English | MEDLINE | ID: mdl-34786697

ABSTRACT

OBJECTIVE: Stroke is the most common cause of epilepsy in older age. Subclinical cerebrovascular disease is believed to underlie some of the 30%-50% of late-onset epilepsy without a known cause (Li et al. Epilepsia. 1997;38:1216; Cleary et al. Lancet. 2004;363:1184). We studied the role of modifiable vascular risk factors in predicting subsequent epilepsy among participants ages 45 or older in the Framingham Heart Study (FHS), a longitudinal, community-based study. METHODS: Participants of the Offspring Cohort who attended FHS exam 5 (1991-1995) were included who were at least 45-years-old at that time, had available vascular risk factor data, and epilepsy follow-up (n = 2986, mean age 58, 48% male). Adjudication of epilepsy cases included review of medical charts to exclude seizure mimics and acute symptomatic seizures. The vascular risk factors studied included hypertension, diabetes mellitus, smoking, and hyperlipidemia. The role of the Framingham Stroke Risk Profile score was also investigated. Cox proportional hazards regression models were used for the analyses. RESULTS: Fifty-five incident epilepsy cases were identified during a mean of 19 years of follow-up. Hypertension was associated with a near 2-fold risk (hazard ratio [HR]: 1.93, 95% confidence interval [CI]: 1.10-3.37, p = .022) of developing epilepsy, even after adjustment for prevalent and interim stroke. In secondary analysis, excluding patients with normal blood pressure who were receiving anti-HTN (anti-hypertensive) treatment (n = 2613, 50 incident epilepsy cases) the association was (HR: 2.44, 95% CI: 1.36-4.35, p = .003). SIGNIFICANCE: Our results offer further evidence that hypertension, a potentially modifiable and highly prevalent vascular risk factor in the general population, increases 2- to 2.5-fold the risk of developing late-onset epilepsy.


Subject(s)
Epilepsy , Hypertension , Stroke , Aged , Epilepsy/epidemiology , Female , Humans , Hypertension/epidemiology , Incidence , Longitudinal Studies , Male , Middle Aged , Risk Factors
8.
J Hazard Mater ; 413: 125407, 2021 Jul 05.
Article in English | MEDLINE | ID: mdl-33930958

ABSTRACT

Red mud (RM) is an industrial waste of the aluminum industry with presently estimated worldwide legacy-site stockpiles of 4 billion tones. RM is typically disposed in the sea, dams or dykes, posing a significant environmental hazard due to its high alkalinity and traces of heavy metals. Despite recent valorization efforts, only 15% of RM deposits are currently utilized. In this work, a novel use of RM to formulate composite phase change materials (CPCMs) is proposed. The CPCM is formulated by milling nitrate salts with RM, compressing and subsequent sintering of the two. Overall good performance over the temperature range of 25-400 â„ƒ is observed. Maximum latent heat of the CPCMs is 58 J/g, while average thermal conductivity and Cp are in the range of 0.77-0.83 W/mK and 1.03-1.31 J/g ℃, respectively. No variations in the melting point or latent heat are observed after 48 cycles. Energy storage density is calculated to be up to 1396 MJ/m3. The working temperature of this novel CPCM make it ideal for waste heat recovery of medium-high temperature waste heat streams providing a valorization pathway and valorization for RM as a by-product for energy-related applications.

9.
Adv Exp Med Biol ; 1317: 35-51, 2021.
Article in English | MEDLINE | ID: mdl-33945131

ABSTRACT

Human remains have been displayed in museums in Europe since many centuries for historical, cultural, and educational reasons. Of particular interest are skeletal remains and body parts that have suffered violent deaths and such remains often feature in Criminology Museums. Despite the well-acknowledged value of human remains in medical education, bioarchaeology, and research, the display of human remains still raises ethical considerations ranging in severity depending on the cultural substrate and legal framework of each country. Recent developments in medical imaging and visualisation are offering an alternative way. Taking into account the emerging issues regarding exhibition and handling of human remains, this research project aims to use virtual methods to reconstruct the circumstances of the death of a nineteenth-century outlaw comprising one of the human exhibits at the Criminology Museum of Athens in Greece.For the purpose of the project, the severed head of the outlaw Stavrou was CT scanned, and the data were used to reconstruct and to evaluate the ballistic trauma sustained at the time of his death. From the scans, it was possible to determine the minimum number of shots, entrance and exit wounds, approximate calibre of the bullets, approximate distance from which they were fired, and general velocity of the round.Shots are fired from the lateral left and backside of the head and bullets exited from the right frontal and temporal area causing extensive damage to the right craniofacial region. The direction of the shots coming from the back and left suggests that Stavrou was more likely ambushed by gendarmerie squads and not shot in a fair fight which would have caused entry wounds in the anterior surface of the body. This is in agreement with historical evidence that placed him in gunfire with his fellow gang member Karapanos against a government squad. On the other hand, the possibility of being captured alive and executed cannot be rejected based only on wound ballistics.This work would be excellent supplementary material to the actual human exhibit for the accurate presentation of Stavrou's history at the Criminology Museum. In addition, it would allow the virtual exhibition of the material for historical and teaching purposes to museums and universities anywhere in Greece and along the globe, thus overcoming the obstacles of moving the actual remains.


Subject(s)
Wounds, Gunshot , Europe , Forensic Ballistics , Greece , Humans , Male , Radiography
10.
Alzheimer Dis Assoc Disord ; 35(4): 291-297, 2021.
Article in English | MEDLINE | ID: mdl-33973881

ABSTRACT

BACKGROUND: Bone mineral density (BMD) is a potential surrogate marker of lifetime estrogen exposure previously linked to increased risk of Alzheimer dementia among elderly women. We examine the association between BMD in the "young old" with imaging biomarkers of brain aging and cognitive performance. METHODS: Offspring participants (N=1905, mean age 66) of a population-based cohort who had BMD, brain imaging and detailed cognitive assessment were included in the study. Sex-stratified, linear, and logistic regression models were used for analysis. RESULTS: Higher femoral neck BMD was associated with lower white matter hyperintensity burden and better performance on Trails B-A in both sexes, even after adjustment for cerebrovascular risk factors. Among women, the positive association with Trails B-A performance was seen only in APOE4 allele carriers. Higher BMD measurements were linked to better visual reproductions test performance in men. Finally, among women, higher femoral trochanter BMD was associated with better logical memory and Hooper visual organization test performance. CONCLUSION: Among the "young old," higher BMD is associated with less white matter hyperintensity burden and better, domain-specific, cognitive performance. This suggests that lifetime estrogen exposure may modulate the degree of cumulative vascular brain injury independent of cerebrovascular risk factors.


Subject(s)
Bone Density , Brain , Aged , Brain/diagnostic imaging , Cognition , Cohort Studies , Female , Femur , Humans , Male
12.
Eur J Gastroenterol Hepatol ; 33(11): 1387-1393, 2021 11 01.
Article in English | MEDLINE | ID: mdl-33470697

ABSTRACT

BACKGROUND: We sought to investigate the prevalence of mucocutaneous manifestations (MCM) and potential associations with clinical characteristics in Greek patients with IBD. METHODS: This was a retrospective observational single-center study. Patients with IBD diagnosis attending a tertiary referral hospital in Heraklion, Crete, from January 2010 to January 2020 were included. Data were extracted with relevant medical information from the IBD registry. Standard statistical tests, descriptive statistics tests, chi-square, Pearson correlation and multivariate analysis tests were performed, using IBM SPSS Statistics 25. RESULTS: A total of 806 IBD patients were included in the study: 463 (57.4%) males, 441 (54.7%) Crohn's Disease, 352 (43.7%) ulcerative colitis and 13 (1.6%) IBD unclassified (IBD-U). Mean age was 50.67 ± 17.67 years, mean age of IBD diagnosis 36.67 ± 16.53 years and mean disease duration 13.65 ± 9.89 years. The prevalence of MCM was 171/806 (21.2%), 9.65% in ulcerative colitis and 30.84% in CD. The presence of MCM was significantly correlated with younger age of IBD diagnosis, longer IBD duration, CD diagnosis, inflammatory behavior and ileal or ileocolonic location of CD, extensive colitis in ulcerative colitis, intestinal manifestations (EIMs) and treatment with immunosuppressant or anti-TNFa. The development of MCM was independently associated with the presence of other EIMs odds ratio (OR), 4.03 [95% confidence interval (CI), 2.60-6.24; P < 0.001] and treatment with immunosuppressant (OR, 1.87; 95% CI, 01.14-3.07; P = 0.013) or anti-TNFa (OR = 2.47; 95% CI, 1.59-3.84; P < 0.01). CONCLUSIONS: In our study, about one-fifth of IBD patients developed MCM that was more frequently present in CD than in ulcerative colitis.


Subject(s)
Colitis, Ulcerative , Crohn Disease , Inflammatory Bowel Diseases , Adult , Aged , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/epidemiology , Crohn Disease/diagnosis , Crohn Disease/drug therapy , Crohn Disease/epidemiology , Greece/epidemiology , Humans , Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/epidemiology , Male , Middle Aged , Retrospective Studies , Young Adult
13.
Semin Pediatr Neurol ; 36: 100855, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33308522

ABSTRACT

A plethora of hormonal and physical changes occur as adolescents grow into adulthood. These changes pose additional challenges for youth with epilepsy. Providers, parents, and patients must be well educated about the hormonal influences, both intrinsic and pharmaceutical, on seizures and antiepileptics (AEDs). In addition, they must be made aware of safe/effective contraception, the importance of pregnancy planning, and potential menstrual and sexual health disturbances related to epilepsy and AEDS. Reproductive and sexual health should be an integral component of transition education and planning for all youth, but is especially important for the youth with epilepsy. While many clinicians will collaborate with adolescent gynecologists or pediatricians, it is important for all child neurologists to be aware of these issues.


Subject(s)
Anticonvulsants/adverse effects , Epilepsy/drug therapy , Epilepsy/metabolism , Health Knowledge, Attitudes, Practice , Hormonal Contraception/adverse effects , Reproductive Health , Sexual Health , Transition to Adult Care , Adolescent , Adult , Female , Humans , Male , Young Adult
14.
Semin Pediatr Neurol ; 36: 100856, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33308524

ABSTRACT

Mental health disorders are prevalent in patients with epilepsy, and adolescents are at particularly high risk. The reason for higher rates of anxiety, depression and suicide in young patients with epilepsy is likely multifactorial, and therefore the approach to treatment has proven challenging. In this review, we discuss important mental health topics for adolescents and young adults with epilepsy, as well as evidence for management. In the past several years, advances have been made in the transition of epilepsy care from pediatric to adult providers, creating a promising method for epilepsy patient engagement and empowerment. Future research into the mental health outcomes from these transition programs may lead to better strategies to support young patients with epilepsy.


Subject(s)
Epilepsy/therapy , Mental Disorders/therapy , Transition to Adult Care , Adolescent , Adult , Comorbidity , Epilepsy/epidemiology , Humans , Mental Disorders/epidemiology , Young Adult
15.
Materials (Basel) ; 13(22)2020 Nov 23.
Article in English | MEDLINE | ID: mdl-33238635

ABSTRACT

The present study proposes nano-calcium oxide (NC) and nano-silica (NS) particles as healing agents in cement pastes, taking into account the curing conditions. Two series of specimens were treated in water and under wetting-drying cycles. The addition of NC (1.5%wt of binder) triggered early healing since cracks were healed within 14 days in underwater immersion and before 28 days at wetting-drying cycles. Attenuated Total Reflectance (ATR) spectroscopy and SEM analysis revealed that the healing products were mainly aragonite and calcite in water conditions and more amorphous carbonates under wetting-drying cycles. The combination of NS and NC (3.0%wt in total) offered healing under both curing conditions before 28 days. The presence of NS assisted toward porosity refinement and NC increased the carbonates' content. The newly formed material was dense, and its elemental analysis by SEM revealed the C-S-H compounds that were also verified by ATR.

16.
Neurology ; 95(24): e3241-e3247, 2020 12 15.
Article in English | MEDLINE | ID: mdl-33097599

ABSTRACT

OBJECTIVE: To assess the risk of incident epilepsy among participants with prevalent dementia and the risk of incident dementia among participants with prevalent epilepsy in the Framingham Heart Study (FHS). METHODS: We analyzed prospectively collected data in the Original and Offspring FHS cohorts. To determine the risk of developing epilepsy among participants with dementia and the risk of developing dementia among participants with epilepsy, we used separate, nested, case-control designs and matched each case to 3 age-, sex- and FHS cohort-matched controls. We used Cox proportional hazards regression analysis, adjusting for sex and age. In secondary analysis, we investigated the role of education level and APOE ε4 allele status in modifying the association between epilepsy and dementia. RESULTS: A total of 4,906 participants had information on epilepsy and dementia and dementia follow-up after age 65. Among 660 participants with dementia and 1,980 dementia-free controls, there were 58 incident epilepsy cases during follow-up. Analysis comparing epilepsy risk among dementia cases vs controls yielded a hazard ratio (HR) of 1.82 (95% confidence interval 1.05-3.16, p = 0.034). Among 43 participants with epilepsy and 129 epilepsy-free controls, there were 51 incident dementia cases. Analysis comparing dementia risk among epilepsy cases vs controls yielded a HR of 1.99 (1.11-3.57, p = 0.021). In this group, among participants with any post-high school education, prevalent epilepsy was associated with a nearly 5-fold risk for developing dementia (HR 4.67 [1.82-12.01], p = 0.001) compared to controls of the same educational attainment. CONCLUSIONS: There is a bi-directional association between epilepsy and dementia. with either condition carrying a nearly 2-fold risk of developing the other when compared to controls.


Subject(s)
Dementia/epidemiology , Epilepsy/epidemiology , Aged , Aged, 80 and over , Apolipoprotein E4/genetics , Case-Control Studies , Comorbidity , Educational Status , Female , Humans , Incidence , Longitudinal Studies , Male , Massachusetts/epidemiology , Middle Aged , Prevalence , Risk
17.
Materials (Basel) ; 13(17)2020 Aug 27.
Article in English | MEDLINE | ID: mdl-32867348

ABSTRACT

The need to increase the durability of clay-based materials, due to their inherent low strength and vulnerability in contact with water, led researchers to examine different options. In this paper, clay mortars were produced using four different activating solutions. Alkali hydroxides, alkali carbonates, and alkali silicates activating solutions were used. Interest is given to long term properties while their behavior to wetting-drying and freeze-thaw cycles is recorded. In total, the results of the experiments indicated the positive effect of the potassium metasilicate on mechanical characteristics presenting, however, low performance at wetting-drying. The combination of sodium metasilicate with sodium hydroxide solution has also presented a positive effect on both mechanical and physical properties. In contrast, sodium carbonate acted better in enhancing physical properties and granting water-resistant abilities. Moreover, the performance of the specimens mixed with water-glass addition presented excellent volume stability and low mass loss in durability tests.

18.
Clin Case Rep ; 8(7): 1301-1303, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32695380

ABSTRACT

We report a case of linear IgA bullous dermatosis, a rare autoimmune blistering disorder that usually presents with the abrupt onset of tense bullae. We also emphasize the importance of direct immunofluorescence for the definitive diagnosis.

20.
Arch Toxicol ; 94(5): 1443-1460, 2020 05.
Article in English | MEDLINE | ID: mdl-32394086

ABSTRACT

Zinc (Zn) is one of the most important essential nutrients of great public health significance. It is involved in numerous biological functions and it is considered as a multipurpose trace element, due to its capacity to bind to more than 300 enzymes and more than 2000 transcriptional factors. Its role in biochemical pathways and cellular functions, such as the response to oxidative stress, homeostasis, immune responses, DNA replication, DNA damage repair, cell cycle progression, apoptosis and aging is significant. Zn is required for the synthesis of protein and collagen, thus contributing to wound healing and a healthy skin. Metallothioneins are metal-binding proteins and they are potent scavengers of heavy metals, including Zn, and protect the organism against stress. Zn deficiency is observed almost in 17% of the global population and affects many organ systems, leading to dysfunction of both humoral and cell-mediated immunity, thus increasing the susceptibility to infection. This review gives a thorough insight into the most recent evidence on the association between Zn biochemistry and human pathologies, epigenetic processes, gut microbial composition, drug targets and nanomedicine.


Subject(s)
Environmental Pollutants/toxicity , Zinc/toxicity , Aging , Animals , Apoptosis , Homeostasis , Humans , Metallothionein , Metals, Heavy , Oxidative Stress , Pharmaceutical Preparations , Protective Agents , Transcription Factors
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