Aging Process Research Articles

Male Sex and Ageing are Independent Risk Factors for Sarcopenia Stage in Patients With Chronic Kidney Disease Not Yet on Dialysis.

The risk of sarcopenia in older adults with chronic kidney disease (CKD) not yet on dialysis is controversial. The aims of this study were to investigate the association among sarcopenia, diabetes and predialysis CKD and evaluate the impact of gender and ageing on the risk of sarcopenia statuses in older patients with predialysis CKD. The participants aged ≥60 years old were recruited from the community of New Taipei City, Taiwan. Handgrip strength, appendicular skeletal muscle mass and the 6-m walk were measured. The diagnosis of sarcopenia was established based on the consensus of Asian Sarcopenia Working Group 2019. These older adults were categorised into G1, G2 and G3-5 according to the guidelines of Kidney Disease Improving Global Outcomes (KDIGO) after calculating the estimated glomerular filtration rate by the Modification of Diet in Renal Disease equation. The Chi-square test and ANOVA were used to estimate the difference of categorical and continuous variables, respectively. Polytomous logistic regression was employed to assess the odds ratio (OR) and 95% confidence intervals (CIs) of the sarcopenia status and sarcopenia-associated risk factors in the predialysis CKD patients. All tests were two-sided, and p < 0.05 was defined as statistical significance. Among the 3648 older adults (mean age: 71.9 ± 6.07 years), including 1701 males and 1947 females, 870 (23.9%), 94 (2.58%) and 48 (1.32%) had possible sarcopenia, sarcopenia and severe sarcopenia, respectively. After adjustment, the risk for possible sarcopenia, sarcopenia and severe sarcopenia significantly increased with ageing (OR = 1.11, 1.10 and 1.23; 95% CI = 1.10-1.13, 1.07-1.15 and 1.18-1.30, respectively) and male gender (OR = 2.26, 20.3 and 25.4; 95% CI = 1.87-2.73, 11.5-36.0 and 11.3-57.2, respectively). Compared with KDIGO G1, no significant association between KDIGO G3-5 and the statuses of sarcopenia was observed (OR = 0.97, 0.88 and 0.91; 95% CI = 0.75-1.26, 0.43-1.78 and 0.37-2.27, p = 0.821, 0.718, 0.838, for possible sarcopenia, sarcopenia and severe sarcopenia, respectively). Ageing and male gender indicated a significant risk for higher sarcopenia status in older patients with predialysis CKD (0.027-fold/year and 0.284-fold, respectively) (p < 0.0001). This study illuminated the importance of the male sex and the ageing process on the risk of sarcopenia progression in patients with predialysis CKD. Early clinical screening and aggressive treatment for the prevention of higher sarcopenia status in advanced older male adults with predialysis CKD are recommended.

A study on microstructure evolution of MCrAlY coatings after thermal aging in Te environment

The effects of thermal exposure on tellurium (Te) diffusion behavior in MCrAlY coatings were investigated at 800 °C in Te vapor. The results showed that the diffusion depth of Te in MCrAlY coatings gradually increased with the exposure time, and the dense Cr3Te4 layer formed on the coating surface in the initial stage was no longer continuous, especially under aging conditions with higher Te concentration. The high Cr content of the coating promoted the solid phase transition of the surface reaction product from Cr3Te4 to Cr7Te8, and resulting in the formation of large α-Cr phase either within or beneath the reaction layer during long aging processes. As a result of this phase transition, excess Te atoms were released from Cr3Te4 and continued to diffuse into the coating. Te did not exhibit obvious intergranular diffusion characteristics within the coating. When it encountered Y, it was captured by Y and formed a YTe phase. After aging for 3000 h, Te was distributed throughout the coating, and numerous voids were formed at the interface between the coating and the substrate. These two factors deteriorated the plasticity and adhesion of the coating. Results from molten salt corrosion tests indicated that the high content of Cr and Al in the coating, as well as high densities of grain boundaries providing diffusion pathways, reduced the corrosion resistance of the coating to molten salt.

The effects of UV aging process on the structure and properties of high-tenacity poly(ethylene terephthalate) industrial fiber

The high-tenacity poly(ethylene terephthalate) (HT PET) industrial fibers (1100 dtex/ 192f) were fixed in position with a constant fiber length and subjected to accelerated artificial ultraviolet exposure with temperature of 50 °C to assess their degradation mechanism. The structural evolutions were evaluated using a combination of ex-situ wide-angle X-ray diffraction (WAXD), ex-situ small angle X-ray scattering (SAXS), Fourier transform infrared spectroscopy (FTIR), and intrinsic viscosity tests based on the relaxed aged samples after different aging process. The results indicate that the structures and properties evolutions of HT PET industrial fiber under UV aging process can be categorized into three stages. In the pre-aging stage (t ≤ 0.5d), the fiber experiences a slight decline in tenacity and thermal shrinkage properties due to the combined impact of UV radiation and heat treatment. Subsequently, in the mid-aging stage (0.5d < t ≤ 28d), a notable decrease in the fiber's elongation at break is observed, accompanied by visible macroscopic defects arising from photo-oxidative aging on the fiber surface after 16 days of exposure. While the fiber's unit cell and atomic positions remains stable on atomic scale, the lamellar thickness and long period witness a significant reduction owing to high-orientation molecular breakages in the mesophase region. Moreover, rearrangement of molecular chains leads to a reduction in the tilting angle. In the late-aging stage (t > 28d), the degradation rate of mechanical and thermal shrinkage properties of the fiber decelerates, alongside a decline in intrinsic viscosity. These results suggest that the fiber's crystallinity remains unchanged post UV aging, with the deterioration in mechanical properties of HT PET industrial fiber primarily attributed to molecular degradation during UV exposure.

Ameliorating the microstructure and properties of a Cu[sbnd]Cr alloy by introducing a high-temperature short-time treatment into the thermo-mechanical process

The optimization of process is essential for improving the overall properties of high-strength and high-conductivity Cu alloys. This study introduces a high-temperature short-time treatment (HTSTT, 850 °C/5 min) into the thermo-mechanical process of a CuCr alloy. Following the process of “solid solution - cold rolling - HTSTT - cold rolling - aging”, the tensile strength of the alloy increases from 450 MPa to 508 MPa, with the electrical conductivity increasing from 82.2 %IACS to 86.4 %IACS when compared to the conventional process of “solid solution - cold rolling - aging” under the same total deformation condition. The reasons for the improvement in the comprehensive properties of the alloy after introducing HTSTT are analyzed through microstructural characterization. The results indicate that the HTSTT promotes the occurrence of recrystallization, leading to grain refinement, which results in smaller grain sizes during subsequent processing. Additionally, the introduction of HTSTT changes the main texture of the alloy from 〈100〉//X to 〈111〉//X during the process, which is beneficial to enhancing the alloy's strength and electrical conductivity. More importantly, the HTSTT facilitates the precipitation of solute Cr atoms, leading to the formation of a significant quantity of nanoscale Cr particles, most of which are spherical with an average size of 27 nm. During the subsequent cold rolling process, these Cr particles effectively pin dislocations and promote their proliferation, leading to the precipitation of a large number of smaller Cr particles during the aging process, with an average size of 4.8 nm. These finer Cr particles are crucial for precipitation strengthening. This paper offers valuable insights into the microstructural optimization and performance enhancement of high-strength and high-conductivity Cu alloys.

Evaluation of the properties of high-content degraded crumb rubber–modified asphalt under thermal oxidation and weathering aging

In this study, the properties of high-content degraded crumb rubber–modified asphalt (HCDRA) under thermal oxidation and weathering aging were analyzed by the fluorescence microscopy test, temperature sweep test, zero shear viscosity test, attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) test, and gel permeation chromatography (GPC) test. Morphological structure result shows that after various degrees of thermal oxidation and weathering aging, the number and size of crumb rubber (CR) particles in HCDRA became smaller. Besides, with the deepening of the degree of oxidization, the rutting resistance of HCDRA decreases firstly and then increases. The improvement of the anti-aging and temperature sensitivity of HCDRA is better than that of neat asphalt and 20 % content CR-modified asphalt. Moreover, thermal oxidation and weathering aging make HCDRA more sensitive to temperature, and the temperature sensitivity of HCDRA is more affected by long-term aging relative to neat asphalt and 20 % content CR-modified asphalt. ATR-FTIR test and GPC test show that the complex modulus of HCDRA increases with the increase of carbonyl groups after aging, and HCDRA becomes soft and then hard during the aging process with the increase of macromolecule polymer content. Lastly, cluster analysis and principal component analysis reveal that the degree of asphalt oxidation has a strong influence on failure temperature and zero shear viscosity, and small molecule polymer has a significant effect on the temperature sensitivity of rheological properties.

Evolving Concepts of Pain Management in Elderly Patients.

The elderly population typically suffer from a variety of diseases that mostly reflect the degenerative changes linked with the aging process. These diseases may be exacerbated by acute pain or by an abrupt aggravation of previously stable chronic pain. Physical and psychological changes associated with aging may influence one's experience of pain and, as a result, the severity of pain. Pain treatment in the elderly can be complex and is often a budgetary burden on the nation's health care system. These difficulties arise, in part, because of unanticipated pharmacodynamics, changed pharmacokinetics, and polypharmacy interactions. Therefore, it is critical to integrate a multidisciplinary team to develop a management strategy that incorporates medical, psychological, and surgical methods to control persistent pain conditions. It is in this critical process that pain prediction models can be of great use. The purpose of pain prediction models for the elderly is the use of mathematical models to predict the occurrence and intensity of pain and pain-related conditions. These mathematical models employ a vast quantity of data to ascertain the many risk factors for the development of pain problems in the elderly, whether said risks are adjustable or not. These models will pave the way for more informed medical decision making that are based on the findings of thousands of patients who have previously experienced the same illness and related pain conditions. However, future additional research needs to be undertaken to build prediction models that are not constrained by substantial legal or methodological limitations.

THE RELATIONSHIP BETWEEN SELF-ESTEEM AND POST-POWER SYNDROME IN ELDERLY RETIREMENT IN THE ELDERLY POSYANDU JATIREJO VILLAGE, NGANJUK REGENCY

Background. The aging process is a natural stage of human life, and one of the phases faced by the elderly is retirement. Retirement often triggers anxiety, fear, and other psychological symptoms, known as Post-Power Syndrome. The purpose was to determine the relationship between self-esteem and Post-Power Syndrome in the elderly during retirement. Research Method. This research used a correlational study with a Cross-Sectional design. This research was conducted in July 2024 at the Elderly Posyandu Jatirejo Village, Nganjuk Regency. The sample size was 35 respondents, inclusion criteria are elderly ?60 years old, have not worked for ?1 year, are cooperative, healthy, and do not have physical disabilities. The independent variable is self-esteem and the dependent variable is Post-Power Syndrome in the elderly. Collecting data on self-esteem with Post-Power Syndrome elderly using a questionnaire sheet. Statistical tests using Spearman rank with a significant ? ? 0.05. Findings. Based on the results of research from 35 respondents, most of them showed high self-esteem, namely 19 respondents (54.3%) and 18 respondents (51.4%) experienced mild Post-Power Syndrome. The results of the Spearman rank correlation test show a p-value of 0.012, and r= -0.42 as moderate and negative correlation which means that there is a relationship between self-esteem and Post-Power Syndrome in the Elderly Retirement Period. Conclusion. The higher self-esteem felt by the elderly will decrease the Post Power Syndrome experienced. Appropriate psychological and social interventions in this regard are essential to improve the self-esteem and psychological well-being of the elderly in retirement.

Cellular Senescence and Anti-Aging Strategies in Aesthetic Medicine: A Bibliometric Analysis and Brief Review.

Skin aging is the most obvious feature of human aging, and delaying aging has become a hot and difficult research topic in aesthetic medicine. The accumulation of dysfunctional senescent cells is one of the important mechanisms of skin aging, based on which a series of anti-aging strategies have been generated. In this paper, from the perspective of cellular senescence, we utilize bibliometrics and research review to explore the research hotspots and trends in this field, with a view to providing references for skin health and aesthetic medicine. We obtained literature related to this field from the Web of Science Core Collection database from 1994 to 2024. Bibliometrix packages in R, CiteSpace, VOSviewer, Origin, and Scimago Graphica were utilized for data mining and visualization. A total of 2,796 documents were included in the analysis. The overall trend of publications showed a continuous and rapid increase from 2016-2023, but the total citations improved poorly over time. In this field, Journal of Cosmetic Dermatology, Journal of Investigative Dermatology, Experimental Gerontology are core journals. Kim J, Lee JH, Lee S, Rattan SIS, Chung JH and Kim JH are the core authors in this field. Seoul National University is the first in terms of publications. Korea is the country with the most publications, but USA has the most total citations. Top 10 keywords include: gene-expression, skin, cellular senescence, cell, oxidative stress, antioxidants, in vitro, fibroblasts, mechanism, cancer. Current research trends are focused on neurodegeneration, skin rejuvenation, molecular docking, fibrosis, wound healing, SASP, skin barrier, and antioxidants. The core literature and references reflect topics such as the major molecular pathways in the aging process, and the relationship with tumors. This field of research has been rapidly rising in recent years. Relevant research hotspots focus on oxidative stress, fibroblasts, and senescence-associated secretory phenotype. Anti-aging strategies targeting cellular senescence hold great promise, including removal of senescent cells or attenuation of SASP factors, corresponding to senolytics and senomorphics therapies, respectively.

The effect of carbon black on degradation of pipe grade black polyethylene in high concentration chlorine dioxide solutions

In this research, the impact of carbon black on the accelerated degradation of pipe grade polyethylene (PE100) exposed to high levels of chlorine dioxide (150 ppm) is examined. Tensile testing reveals a faster degradation rate in black samples compared to neat samples, indicating a detrimental effect of carbon black aggregates on the polymer's aging process. Rheological analysis shows changes in molecular weight and structure due to chemical degradation and chain scission and can be a reliable method for detecting slight changes in molecular structure. Isothermal crystallization shows a slowdown in crystallization kinetics at first, explained by gel-formation due to crosslinking which hinder the crystallization, and then an increase in the kinetics as apparently the chain scission gets dominant again. Neat samples exhibit a higher density of tie molecules, indirectly revealed by much more fibrils in crack wall observed in FESEM images, suggesting better resistance to chemical degradation while the black sample shows a much less fibrillar crack wake and becomes almost completely devoid of any fibrils at later stages of aging. The fibrils, which essentially offer a load-bearing role against the widening and growth of the crack play a key role in resistance to slow crack growth (SCG). Therefore, the higher SCG resistance is expected for neat grade compared to black samples. The study proposes a dual-layer pipe design with a UV-resistant black outer layer and an oxidation-resistant neat inner layer to prolong the lifespan of PE100 pipes by protecting against UV radiation and chemical reactions. This solution offers increased durability, lower maintenance costs, and environmental sustainability benefits.

Increased inflammation in older high-pressure glaucoma mice

Besides an elevated intraocular pressure (IOP), advanced age is one of the most crucial risk factors for developing glaucoma. βB1-Connective Tissue Growth Factor (βB1-CTGF) high-pressure glaucoma mice were used in this study to assess whether glaucoma mice display more inflammatory and aging processes than age-matched controls. Therefore, 20-month-old βB1-CTGF and corresponding wildtype (WT) controls were examined. After IOP measurements, retinas were processed for (immuno-)histological and quantitative real-time PCR analyses. A significantly higher IOP and diminished retinal ganglion cell numbers were noted in βB1-CTGF mice compared to WT. An enhanced macrogliosis as well as an increased number of microglia/macrophages and microglia was detected in retinas of old glaucoma mice. Interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and transforming growth factor-β2 were upregulated, suggesting an ongoing inflammation. Moreover, βB1-CTGF retinas displayed an increased senescence-associated β-galactosidase staining accompanied by a downregulation of Lmnb1 (laminin-B1) mRNA levels. Our results provide a deeper insight into the association between inflammation and high-pressure glaucoma and thus might help to develop new therapy strategies.

Immunofluorescence Staining of Murine Spinal Cord Sections to Evaluate Microglial Activation and Astrogliosis.

Microglia and astrocytes are the main components of the central nervous system (CNS). Upon activation, microglia is able to phagocyte cell debris, pathogens, and toxins; astrocytes support neuronal functions, blood-brain barrier (BBB) homeostasis, and neurotransmitter uptake and metabolism. Furthermore, both cell types can produce cytokines and chemokines. Aging impacts microglia and astrocytes by promoting the production of pro-inflammatory cytokines, impairing microglial phagocytosis and motility and astrocyte glutamate uptake. During neurodegenerative and neuroinflammatory diseases, the aging process may be accelerated contributing to the alteration of CNS glial cells functions. Multiple sclerosis (MS) is an autoimmune, demyelinating disease in which immunosenescence can promote the conversion from relapsing-remitting form to progressive disease. The murine model of experimental autoimmune encephalomyelitis (EAE) allows to investigate MS pathogenesis. Furthermore, EAE can be developed as acute or progressive, mimicking different forms of human MS. Microglia and astrocytes report morphological and functional changes during neuroinflammation that can be investigated in different ways. We here present a protocol for the study of glial cell activation in the spinal cord tissue of EAE mice.

Telomere length and 4-year changes in cognitive function in an older Mediterranean population at high risk of cardiovascular disease.

Cognitive decline, a common process of brain ageing, has been associated with telomere length (TL). Delving into the identification of reliable biomarkers of brain ageing is essential to prevent accelerated cognitive impairment. We selected 317 non-smoking 'Prevención con Dieta Mediterránea-Plus' (PREDIMED-Plus) participants (mean age, 65.8 ± 5.0years) with metabolic syndrome from two trial centres who were following a lifestyle intervention. We measured TL and cognitive function at baseline and after 3 and 4years of follow-up, respectively. Associations between baseline or 3-year changes in TL and baseline or 4-year changes in cognitive function were analysed using multivariable regression models. Baseline TL was not associated with baseline cognitive performance. Nevertheless, longer baseline TL was associated with improved 4-year changes in the Executive Function domain (β: 0.29; 95%CI: 0.12 to 0.44; P < 0.001) and the Global Cognitive Function domain (β: 0.19; 95%CI: 0.05 to 0.34; P =0.010). Besides, a positive association was found between longer baseline TL and improved 4-year changes in the animal version of the Verbal Fluency Test (β: 0.33; 95%CI: 0.12 to 0.52; P =0.002). By contrast, 3-year changes in TL were not associated with changes in cognitive function after 4years. Longer baseline TL could protect from cognitive decline and be used as a useful biomarker of brain ageing function in an older Mediterranean population at risk of cardiovascular disease and cognitive impairment.

Comprehensive Geriatric Assessment of Rural Elderly of Odisha – Results from a Community-based Survey

Abstract Background: India is progressing toward an increasing trend in of the geriatric population. By 2050, it is expected to double from 10.8% to 20%. A decrease in functional and locomotor activity among the geriatric population impairs the process of healthy aging. Methodology: The study assessed the fall risk, frailty, and limitation in the activity of daily living among the individuals aged 60 years or more in rural area of Khordha district in Odisha. The cross-sectional study with 188 participants in a rural area assessed the functional ability of the elderly with Fall Risk Assessment Test Scale, Clinical Frailty Scale, and Katz Index. Results: The study reported that 11.7% (confidence interval [CI] = 7%–17%) were medium to high risk of fall, 24% (CI = 18%–30%) were mildly frail, 29% (CI = 22%–36%) were vulnerable, and 10.6% (CI = 6%–15%) had limitation in the activity of daily living. Age, difficulty in vision, decreased sleep duration, and chronic disease were significant determinants of the limitation in the functional ability of the elderly. Conclusion: Elderly population are at higher risk of fall, increased frailty, and limitation in activity of daily living. Comprehensive geriatric assessment, including the physical, psychological, and nutritional assessment, needs to be integrated to meet the health-care needs of the elderly in primary health care.

Design of thermomechanical processes for tailored microstructures: Methodology and application to nanocrystalline titanium alloy Ti-13Nb-13Zr (NanoTNZ)

Thermomechanical processes enable tailoring of material properties and microstructures for advanced products. In medical technology, next-generation titanium implants require tailored material properties to improve health and quality of life. However, the interaction correlation between process parameters and material properties poses a major challenge for the design of thermomechanical manufacturing processes.In this paper, we present a methodology for the design of thermomechanical processes to achieve tailored microstructural properties through forming technology and heat treatments. The methodology consists of five systematic steps to address the complexity of multiphysical coupling relationships between temperature, stress, microstructure and alloy composition, and to provide a guideline for effective implementation. It is applied to the production of nanostructured Ti-13Nb-13Zr (NanoTNZ) alloy for dental implants. The designed process of severe plastic deformation, recrystallization treatment and aging lead to nanostructured microstructures smaller than 200 nm. The resulting mechanical properties (UTS > 980 MPa, Young’s modulus of 73 GPa) meet the desired goals for improved biomedical implant-bone interactions. The tailored material properties and microstructures of NanoTNZ are therefore highly promising for use as an implant material.The case study demonstrates the importance of a systematic method to manage the complexity of multiphysical coupling relationships in the design of thermomechanical processes to enable tailored microstructures for advanced materials and products.

Zircon U-Pb Age and Hf-O Isotope Evidence of the Taihua Complex on the Southern Margin of the North China Craton: Implications for Its Magmatic Process During the Early Paleoproterozoic

The Xiaoqinling is the largest terrane of the Taihua Complex and records Paleoproterozoic silicic magmatism, which is one of the most potential areas for understanding secular changes in tectonic processes during the Tectono-Magmatic Lull (TML). In this study, we use zircon U–Pb dating, Lu–Hf and O isotopic analysis to constrain the age, provenance, and magmatic processes of the protoliths for the Paleoproterozoic granitic gneiss, tonalitic gneisses, and migmatitized tonalitic gneiss from the Xiaoqinling area. The isotopic composition of zircon provides a key proxy for querying the crustal record. Integration of our new U–Pb and Hf–O isotope data with available published data from other regions of the North China Craton (NCC), allows us to better assess the secular changes of the North China Craton during the magmatic lull at ∼2.3 Ga. This study shows that the protolith of the tonalitic gneisses in the study area have crust-like Hf–O isotopic compositions with slightly negative to positive εHf(t) (−3.0− +2.1) and low to moderately elevated δ18O values (2.71–7.87‰), indicating a mixed origin of continental crust assimilated by mantle-derived magmas.

Examining the relationships between pain, activities of daily living, and perceptions of overall health in older adults with breast cancer: Results from a brief geriatric screening.

273 Background: Geriatric assessment has been identified as an essential component to caring for patients with cancer who are over 65 years old. Prior research suggests that physical pain and illness perceptions each impact important health behaviors. This retrospective study utilized a brief geriatric screen to examine the relationships between pain levels, activities of daily living (ADLs), and perceptions of overall health for older adults with breast cancer. Implications for methods to improve the patient experience for this population are considered. Methods: The Senior Adult Oncology Program (SAOP) screening tool was administered to 429 patients age 65 or older at a breast oncology clinic. A total ADL score was computed by summing patient-reported responses to 13 ADL items, such as ability to dress oneself, feed oneself, and remember to take medications. A higher ADL score indicates greater difficulty with these responsibilities. Pain was assessed using a 10-point scale; scores were dichotomized to form a low-pain group (scores 0-4) and high-pain group (scores 5-10). Overall Health was assessed on a 1-10 scale, with higher scores indicating perceptions of greater health. Demographic and medical information was abstracted from patients’ electronic health records. Independent samples t-tests examined differences between the high-pain and low-pain groups in total ADL score and self-assessed Overall Health. Results: The average age of the sample was 76 years old (range = 65-89 years). Approximately half of the sample identified as White (48%); 20% identified as Black. In comparing the high-pain and low-pain groups, the high-pain group reported significantly greater difficulty with ADLs (M score = 3.25, 1.41, respectively; p=.026). Additionally, patients endorsing high pain levels reported significantly worse Overall Health as compared to patients endorsing low levels of pain (M= 7.50, 6.11, respectively; p=.001). Conclusions: Older adults with breast cancer experiencing high levels of pain demonstrated greater difficulty with ADLs and worse perceptions of overall health. It is critical that pain is assessed early and often for older adults with breast cancer. Early identification of high pain levels in this population could allow those in need to receive pharmacological and/or behavioral treatments for pain, which may maintain stability or promote improvement in ADLs and perceptions of one’s health. Incorporating brief pain assessments into future geriatric screening tools could improve the process of aging during and after breast cancer.

Osteoporosis and inflammation: Cause to effect or comorbidity?

Osteoporosis (OP) was long viewed as an inevitable process of aging, due to an imbalance between osteoclast bone resorbing and osteoblast bone formation function, leading to a negative balance in bone remodeling. This leads to low bone mass and increased bone fragility putting the patient at risk for fracture. While this view still holds, a better understanding disclosed that OP can occur at any age, as a comorbidity or a complication of many diseases and treatments. Differentiation, maturation, and function of osteoclasts and osteoblasts are affected by many factors from different morbidities: endocrine, metabolic, mechanical and inflammatory. Inflammatory diseases are often complicated by a generalized bone loss that subsequently leads to OP. Factors such as glucocorticoid treatment, immobilization, malnutrition, and insufficient intake of vitamin D play a role. However, the inflammatory process itself is involved and the resulting bone loss is termed immune-mediated bone loss. Experiments on animals and on humans, in addition to clinical studies, shed light on the role of inflammation in OP.

Effect of pulse current on the creep ageing behavior of pre-strained 2195 Al-Li alloy

Pre-strained aluminum lithium (Al-Li) alloy plates have ultra-high strength and comprehensive performance after aging treatments, and are widely used in the aerospace industry. The initial increase in dislocation density caused by these pre-strains will significantly affect the evolution of deformation, microstructure, and mechanical properties during the pulse current assisted creep ageing forming process. Therefore, the effect of pulse current on the creep ageing behavior of 2195 Al-Li alloy with different pre-strains (0%, 4%, and 8%) was investigated. As the pulse current increases within the first 1h creep aging process of the various pre-strain samples, the 1h creep strain significantly increases and the subsequent steady-state creep rate slightly reduce. Moreover, the larger the pre-strain, the higher the total creep strain. Pulse current promotes the movement and recovery of initial dislocations, and promotes the fine formation of T1 phase and suppresses the nucleation of θ' and phase, thereby improving mechanical properties. Compared with the conventional creep ageing process, the pulse current acting on pre-strained 2195 Al-Li alloy significantly increased the peak aged strengthen and shorten the peak aging time. Meanwhile, the peak time platform period has also been significantly extended. It is evident that the application of pulse current assisted creep ageing forming process to pre-strained 2195 Al-Li alloy plates can significantly improve formability and mechanical properties, enlarges the forming process window and realize collaborative manufacturing of Al-Li alloy component shape and performance.

Thermosensitive polymer/nanosilica hybrid as a multifunctional additive in water-based drilling fluid: rheologicalproperties and lubrication performance as well as filtration loss reduction capacity

In previous studies, for obtaining a flat rheological drilling fluid, binary and ternary thermosensitive silica (SiO2) nanohybrids as rheological modifiers were synthesized using N-isopropylacrylamide with a thermal association temperatureof 32-33 oC as the thermosensitive monomer [J. Petrol. Sci. Eng. 219 (2022), 111096; Geoenergy Science and Engineering 228 (2023), 211934]. However, the as-synthesized SiO2 nanohybrids exhibited limited performance and low thermal transition temperature. Thus surface initiated atom transfer radical polymerization was utilized to graft hydrophilic poly(ethylene glycol) methyl ether methacrylate (PEGMA) onto SiO2 surface to obtain PEGMA/SiO2 nanohybrids with an elevated thermal association temperature of 75°C. The morphology and structure of the as-synthesized PEGMA/SiO2nanohybrid were characterized by infrared spectroscopy and transmission electron microscopy; and its effects as a thermosensitive multifunctional additive on the rheological properties and lubrication performance as well as filtration loss reduction capacity of a water-based drilling fluid were investigated. Results indicate that the drilling fluids with 1.0% PEGMA/SiO2 nanohybrids exhibited obvious thermal thickening behavior in the temperature range of 70-80 °C; at low temperatures, however, they had a significant viscosity reduction effect therein. At room temperature, the apparent viscosity and plastic viscosity were reduced by 68% and 50%, respectively. Besides, due to the tightly packed plugging layer formed by PEGMA/SiO2 nanohybrids and bentonite, the filtration loss of the drilling fluids containing 1.0% PEGMA/SiO2 nanohybrid was reduced by 37% as compared with that of the base slurry; and the lubrication coefficient was decreased by up to 50%. Moreover, the high-temperature aging process promoted the intermolecular interactions of the nanohybrids and their interaction with bentonite flakes, thereby further improving the rheological behavior, filtration reduction ability, and lubricity of the drilling fluids. The as-synthesized thermosensitive PEGMA/SiO2 nanohybrids with excellent multifunctionality could find promising application in water-based drilling fluids.

Soil urease functional stability to Hg pollution: An ecotoxicological perspective.

Mercury (Hg) is a persistent soil pollutant, and its toxicity can be evaluated using soil enzyme indicators. However, a thorough understanding of how the enzyme resists and remains resilient to Hg stress is essential, as it significantly impacts the accuracy of toxicity assessments. Therefore, it is worthwhile to understand the functional stability of urease in soil under Hg pollution. This study compares the effects of Hg at different concentrations and exposure times on soil urease. Results indicate that soil urease activity was enhanced in the first two hours under low levels of Hg pollution, decreased after six hours of acute Hg pollution, and reached its maximum reduction in 24 hours. The urease in fluvo-aquic soil, with higher soil organic matter showed higher resistance to Hg acute pollution than that in red soil. Over a longer aging process, soil urease activity gradually recovered with time. Hormesis effects were observed in red soil under high Hg stress after 30 days, showing the strong resilience of urease enzyme function to Hg pollution. The ecological dose, ED10, (the Hg concentration causing a 10% reduction in soil urease activity) ranged from 0.09 to 0.59 mg kg-1 under short-term exposure, and was lower than that under a longer aging process (0.28 to 2.71 mg kg-1). Further, aging reduced the Hg ecotoxicity due to decreased Hg availability and the resilience of soil urease activity. This indicates that the risk of Hg pollution estimated by soil urease as an indicator depends on exposure time and enzyme stability. These factors need consideration in heavy metal pollution assessments using soil enzymes.