25 research outputs found
SOME COMPARATIVE OPINIONS REGARDING THE WORKING OF FIBERS AND MATRIX ON AXIAL STRESS LIMIT. MATRIX WITH LONGER FIBER EXTENSIONS
This paper falls within the current scientific and technical research concerns related to structures made of long fiber composite materials. An essential problem is the co-operation of the matrix material with that of the fibers in the composite layers under the action of external loads, until the structure is damaged. In the present case, the case is taken into account if the material of the matrix is characterized by elongations superior to those of the fibers, so that they will break before the damage of the matrix. The linear-elastic behavior of the fibers is considered until their rupture and, obviously, the destruction of the composite
SOME COMPARATIVE OPINIONS REGARDING THE EVALUATION OF MAXIMUM STRESSES IN LONG FIBER REINFORCED COMPOSITES
This paper falls within the scope of current concerns for scientific and technical research, relating to technical structures made of composite materials, recognized for their mechanical, thermal and chemical or erosive resistance characteristics. In this case, the study is characterized by the analysis of the bearing capacity of some composites: a) with fibers applied along them, b) in a certain direction, c) in a direction perpendicular to the fibers, d) the stability of the structure along the fibers, e) in a direction perpendicular to the fibers or f) combined stress
SOME COMPARATIVE OPINIONS REGARDING THE EVALUATION OF MAXIMUM STRESSES IN LONG FIBER REINFORCED COMPOSITES
This paper falls within the scope of current concerns for scientific and technical research, relating to technical structures made of composite materials, recognized for their mechanical, thermal and chemical or erosive resistance characteristics. In this case, the study is characterized by the analysis of the bearing capacity of some composites: a) with fibers applied along them, b) in a certain direction, c) in a direction perpendicular to the fibers, d) the stability of the structure along the fibers, e) in a direction perpendicular to the fibers or f) combined stress
SOME COMPARATIVE OPINIONS REGARDING THE WORKING OF FIBERS AND MATRIX ON AXIAL STRESS LIMIT. MATRIX WITH LONGER FIBER EXTENSIONS
This paper falls within the current scientific and technical research concerns related to structures made of long fiber composite materials. An essential problem is the co-operation of the matrix material with that of the fibers in the composite layers under the action of external loads, until the structure is damaged. In the present case, the case is taken into account if the material of the matrix is characterized by elongations superior to those of the fibers, so that they will break before the damage of the matrix. The linear-elastic behavior of the fibers is considered until their rupture and, obviously, the destruction of the composite
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Impact of Intermediate Hyperglycemia and Diabetes on Immune Dysfunction in Tuberculosis
Supplementary Data:
Supplementary materials are available at Clinical Infectious Diseases online at https://academic.oup.com/cid/article/72/1/69/5857148#274319223 . Consisting of data provided by the authors to benefit the reader, the posted materials are not copyedited and are the sole responsibility of the authors, so questions or comments should be addressed to the corresponding author.Copyright © The Author(s) 2020. Background:
People with diabetes have an increased risk of developing active tuberculosis (TB) and are more likely to have poor TB-treatment outcomes, which may impact on control of TB as the prevalence of diabetes is increasing worldwide. Blood transcriptomes are altered in patients with active TB relative to healthy individuals. The effects of diabetes and intermediate hyperglycemia (IH) on this transcriptomic signature were investigated to enhance understanding of immunological susceptibility in diabetes-TB comorbidity.
Methods:
Whole blood samples were collected from active TB patients with diabetes (glycated hemoglobin [HbA1c] ≥6.5%) or IH (HbA1c = 5.7% to <6.5%), TB-only patients, and healthy controls in 4 countries: South Africa, Romania, Indonesia, and Peru. Differential blood gene expression was determined by RNA-seq (n = 249).
Results:
Diabetes increased the magnitude of gene expression change in the host transcriptome in TB, notably showing an increase in genes associated with innate inflammatory and decrease in adaptive immune responses. Strikingly, patients with IH and TB exhibited blood transcriptomes much more similar to patients with diabetes-TB than to patients with only TB. Both diabetes-TB and IH-TB patients had a decreased type I interferon response relative to TB-only patients.
Conclusions:
Comorbidity in individuals with both TB and diabetes is associated with altered transcriptomes, with an expected enhanced inflammation in the presence of both conditions, but also reduced type I interferon responses in comorbid patients, suggesting an unexpected uncoupling of the TB transcriptome phenotype. These immunological dysfunctions are also present in individuals with IH, showing that altered immunity to TB may also be present in this group. The TB disease outcomes in individuals with IH diagnosed with TB should be investigated further.European Union’s Seventh Framework Programme (FP7 2007-2013 - Health) under grant agreement No 305279
Effect of the Antimicrobial Agents Peppermint Essential Oil and Silver Nanoparticles on Bone Cement Properties
The main problems directly linked with the use of PMMA bone cements in orthopedic surgery are the improper mechanical bond between cement and bone and the absence of antimicrobial properties. Recently, more research has been devoted to new bone cement with antimicrobial properties using mainly antibiotics or other innovative materials with antimicrobial properties. In this paper, we developed modified PMMA bone cement with antimicrobial properties proposing some experimental antimicrobial agents consisting of silver nanoparticles incorporated in ceramic glass and hydroxyapatite impregnated with peppermint oil. The impact of the addition of antimicrobial agents on the structure, mechanical properties, and biocompatibility of new PMMA bone cements was quantified. It has been shown that the addition of antimicrobial agents improves the flexural strength of the traditional PMMA bone cement, while the yield strength values show a decrease, most likely because this agent acts as a discontinuity inside the material rather than as a reinforcing agent. In the case of all samples, the addition of antimicrobial agents had no significant influence on the thermal stability. The new PMMA bone cement showed good biocompatibility and the possibility of osteoblast proliferation (MTT test) along with a low level of cytotoxicity (LDH test)