Accelerated Aging Process Research Articles

Multiscale analysis of the radiooxidative degradation of EVA/EPDM composites. ATH filler and dose rate effect

This study is focused on the radiooxidative degradation of polymeric insulation of electric cables used in Nuclear Power Plants (NPPs). In order to investigate the degradation mechanisms of the insulation, model composites with ATH (Aluminium TriHydrate) filler and blends (without filler) based on a cross-linked mixture of EVA (Ethylene Vinyl Acetate) and EPDM (Ethylene Propylene Diene Monomer) were submitted to gamma-rays. In normal operating conditions of a NPP, the dose rate which electric cables are exposed to is around 0.1Gyh−1. In this work, artificial accelerated ageing test process has been applied at a relatively low dose rate of 7Gyh−1. Gamma-irradiations at higher dose rates typically used to accelerate the ageing, in the range 0.2–1kGyh−1, were also carried out.The first part of the study is focused on irradiations performed at relatively low dose rate and is devoted to the highlighting of the radiooxidative degradation mechanisms of EVA/EPDM blend with and without ATH filler. Correlations between the evolutions of the chemical, morphological and mechanical/electrical properties of the materials occurring after the ageing process are presented. It is shown that the degradation process is governed by radical oxidation mechanism involving chain scissions leading to the formation of carboxylic acids as end-groups. One of the main effects of the ATH filler is the progressive loss of the mechanical properties of the composite upon radiooxidation whereas they are maintained in the case of the unfilled sample. Despite the oxidation of the polymer, no change in the electrical properties of the blend and of the composite could be observed.The second part of the study focuses on the dose rate effect. It is shown that one of the main consequences of an increase of the dose rate from 7Gyh−1 to 0.2–1 kGy h−1 is a reduction of the chain scission process yield by a factor of about 20. Therefore, an important and consistent finding is that there are some limits that must not be exceeded in terms of dose rate to ensure a global satisfactorily representativeness of the accelerated ageing process.

The thermal processing in air of ethylic soybean biodiesel after accelerated aging, with and without antioxidant

Biodiesel is highly susceptible to oxidative degradation during storage or when submitted to thermal processing in air, which is influenced by the composition and the physical–chemical properties of the raw materials, from which it was originated. This work evaluates the influence of synthetic commercial antioxidants on the oxidative degradation of ethylic soybean biodiesel after being submitted to accelerated aging. Biodiesel–antioxidant blends were prepared using a concentration of 500 mg kg−1 of the following commercial antioxidants: 2,6-di-tert-butyl-4-metyl phenol (Ph); 2,2′-methylene-bis (4-methyl-6-tert-butylphenol) (BPh); N,N′-di-sec-butyl-p-phenylenediamine + 2,6-di-tert-butylphenol (PA); and 2-tert-butylhydroquinone (HCA). Samples with and without antioxidant were held for 30, 60 and 90 days in an oven at 43 °C, to accelerate their aging process (ASTM D 4625-04), after which, they were analyzed by thermogravimetry in air, and DSC with real-time view (DSC-RV). The present paper discusses the main volatilization and thermal decomposition steps that occur during the analyses, quantifying the still non-degraded components, as well as the residual carbonaceous products that are formed during the accelerated aging processes or during analysis. HCA and BPh antioxidants showed a more effective action in the maintenance of the biodiesel oxidative stability than Ph and PA antioxidants. The higher was the biodiesel oxidative degradation during aging, the higher was the formation of high molecular weight products, which were quantified by thermogravimetry.

Coir pith/nylon/epoxy hybrid composites and their thermal properties: Thermogravimetric analysis, thermal ageing, and heat deflection temperature

Thermal stability of composites and their constituents becomes an important criterion during their processing and application in different fields. The present work deals with the thermal stability of coir pith/nylon/epoxy hybrid composites by studying the thermogram, heat deflection temperature, and accelerated ageing of these composites. The effect of chemical treatment of coir pith and hybridization on these properties is dealt in detail in the discussion. The composite samples were prepared by hand layup method followed and by compression molding. Coir pith was subjected to different types of chemical treatments—sodium hydroxide, dicumyl peroxide, acrylic acid, acetic acid, sodium hypochlorite, and sulfuric acid before processing. Thermogravimetric analysis of composite samples showed improved thermal stability with treatment of coir pith and hybridization with nylon fabric. The effect of temperature on the ageing of composites was studied after an accelerated ageing process followed by a comparison of retention in impact strength. The thermogram of the samples was found to complement the results obtained in accelerated ageing and heat deflection analysis. J. VINYL ADDIT. TECHNOL., 24:297–303, 2018. © 2017 Society of Plastics Engineers

Improvement of Aroma and Shelf-Life of Non-alcoholic Beverages Through Cyclodextrins-Limonene Inclusion Complexes

Limonene is a monoterpene flavor compound found in several beverages. However, it easily degrades by oxidation reactions at acidic environment contributing to an undesirable off-flavor. Encapsulation technologies can protect compounds from degradation. This work focuses on the effect of using complexes of limonene with α-, β-, and γ- and HP-β-cyclodextrins in non-alcoholic beverages to improve flavor and shelf-life stability due to the chemical structure of cyclodextrins. Spray-drying technology was applied to prepare different cyclodextrin/limonene forms, from which the most promising was selected and further applied in simulated lemon juice beverages. Different drying process conditions were tested, namely feed temperature (120, 160, and 180 °C) and setting of prior incubation (temperature, room and 50 °C; time, 0.17 and 24 h). An inlet temperature of 160 °C favored the encapsulation of limonene into resulting nano/microparticles. Moreover, incubation for 24 h enhanced limonene retention for all complexes, especially for β-cyclodextrin/limonene complexes, which achieved 66% of encapsulation efficiency and a 6.25 w/w of limonene load. The β-cyclodextrin/limonene particles which enabled higher load (160 °C, 24 h) presented particle size ranging between 1 and 3 μm and were chosen to undergo an accelerated aging process in a lemon juice beverage model. This study revealed that the limonene content decreased over time for model and supplemented juice, but decreased less when β-cyclodextrin/limonene particles were added. After 10 days, which mimics 9 months of storage, 40% of complexed limonene remained in the model beverage.

Dissociating Normal Aging from Alzheimer's Disease: A View from Cognitive Neuroscience.

Both normal aging and Alzheimer’s disease (AD) are associated with changes in cognition, grey and white matter volume, white matter integrity, neural activation, functional connectivity, and neurotransmission. Obviously, all of these changes are more pronounced in AD and proceed faster providing the basis for an AD diagnosis. Since these differences are quantitative, however, it was hypothesized that AD might simply reflect an accelerated aging process. The present article highlights the different neurocognitive changes associated with normal aging and AD and shows that, next to quantitative differences, there are multiple qualitative differences as well. These differences comprise different neurocognitive dissociations as different cognitive deficit profiles, different weights of grey and white matter atrophy, and different gradients of structural decline. These qualitative differences clearly indicate that AD cannot be simply described as accelerated aging process but on the contrary represents a solid entity.

HIV Infection and Compromised Mucosal Immunity: Oral Manifestations and Systemic Inflammation.

Mucosal surfaces account for the vast majority of HIV transmission. In adults, HIV transmission occurs mainly by vaginal and rectal routes but rarely via oral route. By contrast, pediatric HIV infections could be as the result of oral route by breastfeeding. As such mucosal surfaces play a crucial role in HIV acquisition, and spread of the virus depends on its ability to cross a mucosal barrier. HIV selectively infects, depletes, and/or dysregulates multiple arms of the human immune system particularly at the mucosal sites and causes substantial irreversible damage to the mucosal barriers. This leads to microbial products translocation and subsequently hyper-immune activation. Although introduction of antiretroviral therapy (ART) has led to significant reduction in morbidity and mortality of HIV-infected patients, viral replication persists. As a result, antigen presence and immune activation are linked to “inflammaging” that attributes to a pro-inflammatory environment and the accelerated aging process in HIV patients. HIV infection is also associated with the prevalence of oral mucosal infections and dysregulation of oral microbiota, both of which may compromise the oral mucosal immunity of HIV-infected individuals. In addition, impaired oral immunity in HIV infection may predispose the patients to periodontal diseases that are associated with systemic inflammation and increased risk of cardiovascular diseases. The purpose of this review is to examine existing evidence regarding the role of innate and cellular components of the oral cavity in HIV infection and how HIV infection may drive systemic hyper-immune activation in these patients. We will also discuss current knowledge on HIV oral transmission, HIV immunosenescence in relation to the oral mucosal alterations during the course of HIV infection and periodontal disease. Finally, we discuss oral manifestations associated with HIV infection and how HIV infection and ART influence the oral microbiome. Therefore, unraveling how HIV compromises the integrity of the oral mucosal tissues and innate immune components of the oral cavity and its association with induction of chronic inflammation are critical for the development of effective preventive interventions and therapeutic strategies.

Evaluation of effect of laser etching on shear bond strength between maxillofacial silicone and acrylic resin subjected to accelerated aging process.

Maxillofacial prosthesis are supported by implants, require a retentive matrix to retain the suprastructure. The retentive matrix is made up of acrylic resin to which the silicone prostheses are anchored by micro-mechanical bond. The delamination of silicone away from the retentive matrix is a persisting problem in implant-supported maxillofacial prosthesis. This study aimed to evaluate the effect of laser etching on the shear bond strength (BS) between acrylic resin and maxillofacial silicone, after 24 h of fabrication and after 200 h of accelerated aging. The samples were prepared according to ISO/TR 11405:1994 in maxillofacial silicone and polymethyl methacrylate resin. The untreated samples were Group A (control), Group B (silicon carbide [SiC] paper abrasion 80 grit size), and Group C (erbium-doped yttrium aluminum garnet laser etching). Then, the samples were coated with primer and bonded to maxillofacial silicone. The samples were subjected to shear BS test in an universal testing machine after 24 h of fabrication and after 200 h of accelerated aging. The results were statistically analyzed using one-way ANOVA and Tukey's HSD post hoc test. The shear BS test after 24 h of fabrication showed better BS in SiC paper abrasion. The shear BS test after 200 h of accelerated aging showed better BS in laser etching compared to SiC abrasion. Laser etching produced better shear BS compared to conventional SiC paper abrasion after 200 h of accelerated aging process.

Accelerated Degradation of Polymer Electrolyte Membrane Fuel Cell Gas Diffusion Layers

In this work, as-received pristine GDLs were degraded (aged) through an accelerated ageing process by immersion into a 35% wt. solution of H2O2 at 90°C for 12 hours. Pristine and degraded GDLs were assembled in custom-built fuel cells for in operando synchrotron X-ray visualization. Electrochemical impedance spectroscopy (EIS) measurements were obtained, while synchrotron X-ray radiography was performed to investigate the effect of ageing on liquid water transport behavior. In both pristine and aged GDLs, the liquid water profile converged to an upper (terminal) threshold in the saturation pattern as the current density increased. The terminal steady state liquid water profile was established at a lower current density for the aged GDLs compared to that of the pristine GDLs. Higher water quantities of liquid water accumulated at the GDL/flow field channel and MPL/carbon fiber substrate interfaces of the fuel cell with an aged GDL compared to the fuel cell with a pristine GDL. The aged GDLs exhibited more liquid water accumulation at lower current densities. Increases in liquid water accumulation and reduced performance were attributed to the reduction in hydrophobicity of the GDL.

Perinatal programming and cardiomyocyte aging

The developmental origins of health and disease hypothesis suggests that the conditions for the development of the organism in the prenatal and early postnatal periods thus affect the expression of genes that program the early onset of cardiovascular and metabolic diseases. Experimental studies demonstrate the major role of epigenetic mechanisms (gene methylation) in this scenario. The review provides data showing that perinatal programming can accelerate aging processes, resulting in early onset of these diseases. It considers the importance of fetal hypoxia as a factor leading to the birth of babies at increased risk for abnormalities of the brain, heart, liver, and kidney, as well as for hypertension and metabolic disorders in later life. The role of oxidative stress and reactive oxygen species in the processes of perinatal programming is discussed.

Associations of alcohol consumption and alcohol flush reaction with leukocyte telomere length in Korean adults.

BACKGROUND/OBJECTIVESTelomere length is a useful biomarker for determining general aging status. Some studies have reported an association between alcohol consumption and telomere length in a general population; however, it is unclear whether the alcohol flush reaction, which is an alcohol-related trait predominantly due to acetaldehyde dehydrogenase deficiency, is associated with telomere length. This cross-sectional study aimed to evaluate the associations of alcohol consumption and alcohol flush reaction with leukocyte telomere length (LTL).SUBJECTS/METHODSThe study included 1,803 Korean adults. Participants provided blood specimens for LTL measurement assay and reported their alcohol drinking status and the presence of an alcohol flush reaction via a questionnaire-based interview. Relative LTL was determined by using a quantitative polymerase chain reaction. Statistical analysis used multiple linear regression models stratified by sex and age groups, and potential confounding factors were considered.RESULTSAge-specific analyses showed that heavy alcohol consumption (> 30 g/day) was strongly associated with a reduced LTL in participants aged ≥ 65 years (P < 0.001) but not in younger participants. Similarly, the alcohol flush reaction was associated with a reduced LTL only in older participants who consumed > 15 g/day of alcohol (P < 0.01). No significant alcohol consumption or alcohol flush reaction associations with LTL were observed in the sex-specific analyses.CONCLUSIONSThe results suggest that older alcohol drinkers, particularly those with the alcohol flush reaction, may have an accelerated aging process.

Accelerated aging of bio-oil from lignin conversion in subcritical water

Accelerated aging of bio-oil derived from lignin was investigated at different aging temperatures (50°C and 80°C) and times (1 hour, 1 day, 1 week, and 1 month). The bio-oil used was produced by the hydrothermal liquefaction of kraft lignin, using phenol as the capping agent, and base (potassium carbonate and potassium hydroxide) and zirconium dioxide as the catalytic system in subcritical water. Elemental composition, molecular weight (by using gel permeation chromatography), and chemical composition (by using gas chromatography–mass spectrometry and 2D nuclear magnetic resonance [18.8 T, DMSO-d6]) of the bio-oil were measured to gain better understanding of the changes that occurred after being subjected to an accelerated aging process. The ligninderived hydrothermal liquefaction bio-oil was quite stable compared with biomass-pyrolysis bio-oil. The yield of the low molecular weight fraction (light oil) decreased from 64.1% to 58.1% and that of tetrahydrofuran insoluble fraction increased from 16.5% to 22.2% after aging at 80°C for 1 month. Phenol and phenolic dimers (Ar–CH2–Ar) had high reactivity compared with other aromatic substituents (i.e., methoxyl and aldehyde groups); these may participate in the polymerization/condensation reactions in the hydrothermal liquefaction bio-oil during accelerated aging. Moreover, the 2D heteronuclear single quantum coherence nuclear magnetic resonance spectra of the high molecular weight fraction (heavy oil) in the aged raw oil in the aromatic region showed that the structure of this fraction was a combination of phenol-alkyl patterns, and the guaiacol cross-peaks of Ar2, Ar5, and Ar6 after aging indicate that a new polymer was formed during the aging process.

Effect of aging and lifestyle on photoreceptors and retinal pigment epithelium: cross-sectional study in a healthy Danish population.

ABSTRACTPhotoreceptors and their supporting retinal pigment epithelium constitute the key functional parts of the retina. Here, a study was undertaken to show how aging and lifestyle factors affect the photoreceptor layer and the retinal pigment epithelium and Bruch’s membrane complex (RPE-BM) in vivo in a healthy Danish population using spectral-domain optical coherence tomography. This was a cross-sectional study of healthy humans aged ≥50 years. All participants were interviewed for medical history and lifestyle factors. Maculae of all participants were scanned using spectral-domain optical coherence tomography. The thickness of the photoreceptor layer and the RPE-BM was measured on one eye from each participant. In 150 eyes of 150 participants, it was found that aging was associated with a decrease in the thickness of the photoreceptor layer (−0.143 μm/year, P = 0.031) and an increase in the thickness of the RPE-BM layer (0.100 μm/year, P = 0.029) at the foveal minimum. Regarding lifestyle factors, alcohol intake or BMI were not associated with any significant trend, but physical inactivity and smoking had effects on the photoreceptor layer (decreased thickness) and the RPE-BM layer (increased thickness) indicating an accelerated aging process of the macula. Taken together, aging affects photoreceptors and the RPE-BM, and these aging trends are accelerated in smokers and the physically inactive.

New techniques for wine aging

The aging of wine requires a long time therefore it can cause loss of time and money. Therefore using of new techniques for wine aging shortens the length of aging time and wines may be placed on the market more quickly. Nowadays, gamma irradiation, ultrasonic waves, AC electric field and micro-oxygenation are the new techniques for wine aging. Gamma irradiation (after fermentation) is accelerated physical maturation method. Gamma irradiation, in a suitable dosage (200 Gy), is a suitable method for improving some wine defects and producing a higher taste quality in wine. The 20 kHz ultrasonic waves aged wine much more quickly than standard aging, with similar quality. The wine treated by 20 kHz ultrasonic waves had a taste equivalent to 1 year aged wine. Wine maturing with AC electric field promises novel process accelerating aging process of fresh wine when suitable conditions are applied. As a result of research, an optimum treatment (electric field 600 V/cm and duration time 3 min) was identified to accelerate wine aging. Harsh and pungent raw wine become harmonious and dainty. This process is equivalent to 6 month aging in oak barrel. Microoxygenation is a very important technique used in aging wines in order to improve their characteristics. The techniques of wine tank aging imply the use of small doses of oxygen (2 ml L−1 month−1 ) and the addition of wood pieces of oak to the wine. Studies concerning these new techniques demonstrated that maturation of wines become more quickly than standard maturation procedures with keeping and improving the wine quality.

The Effect of Accelerated Aging on the Colour Stability of Composite Resin Luting Cements using Different Bonding Techniques.

The main criterion of successful aesthetic restoration is to match the colour of the adjacent teeth. Porcelain laminate veneer is widely practiced indirect restoration in the contemporary aesthetic dentistry. The underlying luting cement colour influences the final outcome of the thin, translucent veneer shade. Hence, colour stability of luting cement is important criteria during their selection. The objective of the study was to assess the colour stability of the different dentin bonding techniques in composite resin luting cements. A total of forty intact, non carious teeth were prepared to receive Porcelain Laminate Veneers (PLV). The lithium disilicate PLV were fabricated, and fitting surface was conditioned with 5% hydrofluoric acid and silane application. According to the bonding technique employed for the cementation of the PLV, the teeth samples were randomly divided into the four groups of ten each. The Group I and Group II samples were conditioned with etch and wash; the polymerization of resin was accomplished with the dual cure for Group I and light cure for Group II. The Group III and Group IV samples were conditioned with self-etch and self-adhesive technique correspondingly. The teeth shade was recorded in similar locations with a spectrophotometer before and after subjecting them to the accelerated ageing process. The ageing process included the thermocycling process in water between 5°C and 55°C for 5000 cycles followed by 100 hours xenon light exposure. The data were analysed with SPSS 19.0 by ANOVA and LSD post-hoc comparison. The higher mean colour change was observed in Group I sample (etch washdual cure) with a ∆E value of 2.491. The ∆E value for Group II (etch wash-light cure) and Group III (selfetch) was 1.110 and 2.357 respectively. The lowest mean colour change was observed in Group IV (self-adhesive) with ∆E at 0.614. Statistical analysis showed significant differences between Group IV and Group I; Group IV and Group III with p<0.05. The self-adhesive and etch-wash light cure luting cements were found to be less susceptible for colour changes due to accelerated ageing.

Optimisation of accelerated ageing of grape marc distillate on a micro-scale process using a Box-Benhken design: influence of oak origin, fragment size and toast level on the composition of the final product

Background and Aims The ageing process, in wooden barrels, is used to improve the sensory quality of wines and distillates. This process, however, is costly, often leading to an alternative strategy of using wood fragments. The main aim of this work was to evaluate the influence of size, toast level and origin of the oak fragments on the composition of grape marc distillates. Methods and Results The accelerated ageing process of grape marc distillate was optimised with a Box–Benhken experimental design. Five dependent variables were evaluated: the concentration of vanillin, whiskey lactone and phenolic substances, the antioxidant activity and the colour parameters to determine the influence of the independent variables: concentration of oak fragments, proportion of ethanol in Galician grape marc distillate (Orujo) and the time of maceration. The concentration of oak fragments was the variable with the greatest effect on the dependent variables evaluated, except for whiskey lactone. The optimal conditions obtained were applied in 11 experimental accelerated ageing processes to study the influence of size, toast level and origin of the oak fragments on the parameters previously mentioned. Conclusions The best results were obtained with the smaller fragment size (granular) from Quercus petraea with medium toast level. The contact time did not significantly influence the parameters evaluated. Significance of the Study This study, performed at a micro-scale, determined the optimum conditions for greater extraction of compounds from oak with beneficial characteristics: volatile compounds with positive notes, vanillin and whiskey lactone, and the phenolic substances with antioxidant properties. This option allows producers to reduce considerably the cost of the process.

Thermal stability of low and high Mw fractions of bio-oil derived from lignin conversion in subcritical water

The thermal stability of bio-oil influences its application in industry and is, therefore, a very important factor that must be taken into consideration. In this study, the stability of low and high molecular weight (Mw) fractions of bio-oil obtained from the hydrothermal liquefaction (HTL) of lignin in subcritical water was studied at an elevated temperature (80 °C) for a period of 1 h, 1 day and 1 week. The changes in molecular weight (gel permeation chromatography (GPC)) and chemical composition (gas chromatography–mass spectrometry (GC–MS) and 2D heteronuclear single quantum correlation (HSQC) NMR (18.8 T, DMSO-d6)) of low and high Mw fractions of the HTL bio-oil (i.e. light oil (LO) and heavy oil (HO)) were evaluated before and after ageing. It was found that only a slight formation of high Mw insoluble structures was obtained during ageing at elevated temperature for 1 week: 0.5% for the LO and 3.1% for the HO. These higher Mw moieties might be formed from different polymerisation/condensation reactions of the reactive compounds (i.e. anisoles, guaiacols, phenols, methylene (–CH2–) groups in phenolic dimers and xanthene). The high Mw insolubles in both the LO and the HO were analysed for structural composition using 2D HSQC NMR to obtain a better understanding of the changes in the composition of bio-oil fractions during the accelerated ageing process. In addition, a chemical shift database in DMSO-d6 was analysed for a subset of phenolic model compounds to simplify the interpretation of the 2D HSQC NMR spectra.

Monitoring the Resistance of the Military Aircraft’s Fuselage

Abstract The article includes the description of the measurements of the military aircraft’s fuselage resistance, conducted for the purpose of identifying corroded spots in the fuselage’s mechanical connections’ structure. Considerations regarding the errors in measuring the single connections of the airframe’s mechanical element pairs and the entire structure of such connections in an actual aircraft are also presented. The paper includes the proposal of the superposition method for locating the mechanical connection pairs with improved electrical resistance. Simultaneously, for the purpose of forecasting the time of exploitation of the selected (most endangered) fuselage mechanical connections pairs, the article proposes conducting (in laboratory conditions) of the accelerated ageing process and converting the results to real-time using the Arrhenius method.

Increased AGE-RAGE ratio in idiopathic pulmonary fibrosis.

BackgroundThe abnormal epithelial-mesenchymal restorative capacity in idiopathic pulmonary fibrosis (IPF) has been recently associated with an accelerated aging process as a key point for the altered wound healing. The advanced glycation end-products (AGEs) are the consequence of non-enzymatic reactions between lipid and protein with several oxidants in the aging process. The receptor for AGEs (RAGEs) has been implicated in the lung fibrotic process and the alveolar homeostasis. However, this AGE-RAGE aging pathway has been under-explored in IPF.MethodsLung samples from 16 IPF and 9 control patients were obtained through surgical lung biopsy. Differences in AGEs and RAGE expression between both groups were evaluated by RT-PCR, Western blot and immunohistochemistry. The effect of AGEs on cell viability of primary lung fibrotic fibroblasts and alveolar epithelial cells was assessed. Cell transformation of fibrotic fibroblasts cultured into glycated matrices was evaluated in different experimental conditions.ResultsOur study demonstrates an increase of AGEs together with a decrease of RAGEs in IPF lungs, compared with control samples. Two specific AGEs involved in aging, pentosidine and Nε-Carboxymethyl lysine, were significantly increased in IPF samples. The immunohistochemistry identified higher staining of AGEs related to extracellular matrix (ECM) proteins and the apical surface of the alveolar epithelial cells (AECs) surrounding fibroblast foci in fibrotic lungs. On the other hand, RAGE location was present at the cell membrane of AECs in control lungs, while it was almost missing in pulmonary fibrotic tissue. In addition, in vitro cultures showed that the effect of AGEs on cell viability was different for AECs and fibrotic fibroblasts. AGEs decreased cell viability in AECs, even at low concentration, while fibroblast viability was less affected. Furthermore, fibroblast to myofibroblast transformation could be enhanced by ECM glycation.ConclusionsAll of these findings suggest a possible role of the increased ratio AGEs-RAGEs in IPF, which could be a relevant accelerating aging tissue reaction in the abnormal wound healing of the lung fibrotic process.

Neuroprotective Effect of TREM-2 in Aging and Alzheimer’s Disease Model

Neuroinflammation and activation of innate immunity are early events in neurodegenerative diseases including Alzheimer's disease (AD). Recently, a rare mutation in the gene Triggering receptor expressed on myeloid cells 2 (TREM2) has been associated with a substantial increase in the risk of developing late onset AD. To uncover the molecular mechanisms underlying this association, we investigated the RNA and protein expression of TREM2 in APP/PS1 transgenic mice. Our findings suggest that TREM2 not only plays a critical role in inflammation, but is also involved in neuronal cell survival and in neurogenesis. We have shown that TREM2 is a soluble protein transported by macrophages through ventricle walls and choroid plexus, and then enters the brain parenchyma via radial glial cells. TREM2 protein is essential for neuroplasticity and myelination. During the late stages of life, a lack of TREM2 protein may accelerate aging processes and neuronal cell loss and reduce microglial activity, ultimately leading to neuroinflammation. As inflammation plays a major role in neurodegenerative diseases, a lack of TREM2 could be a missing link between immunomodulation and neuroprotection.

Study of an Accelerated Aging Process for Conductive Aluminum Alloys

An orthogonal hardness study of 4 factors (the step one aging temperature (T1) and time (t1), and step two aging temperature (T2) and time (t2)) with 3 levels was designed to optimize an accelerated aging process for a newly developed conductive aluminum alloy (Al-0.4wt.%Si-0.3wt.% Mg-0.3wt.%Ce). Statistical analysis of the experimental results indicates that the factor significance ranked from high to low is t2, T2, T1, and t1. The optimal aging process is 140°C×5h+220°C×5h. Experimental validation confirms that all the strength, hardness, elongation and conductivity with the optimized aging process exceed the predictions. Compared with the commonly used T7 process (190°C×20h), the optimized aging process leads to a more superior precipitation effect and much less time. TEM observation indicates the accelerated aging process significantly expedites the precipitating transformation even with much shorter aging time.