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This study investigates the mechanical, fatigue, water absorption, and flammability properties of polyethylene terephthalate (PET) core-pineapple fiber sandwich composites reinforced with silane-treated neem fruit husk (NFH) biosilica additives. The novel approach includes modifying the fiber’s surface and incorporating biosilica to enhance environmental resistance. The composites were prepared using a hand layup method, followed by silane treatment of the biosilica, pineapple fiber, PET core and vinyl ester resin. Subsequently, to evaluate environmental impacts on composite’s performance, sandwich composites were subjected to temperature aging at 40^∘C and 60^∘C in a hot oven for 30 days and warm water aging at the same temperatures in tap water with pH 7.4. According to the results, adding 1%, 3%, and 5 vol.% silane-treated biosilica significantly improved the mechanical properties. The composite with 3% biosilica (L2) showed a tensile strength of 120.8MPa, flexural strength of 194.4MPa, compression strength of 182.4MPa, rail shear strength of 20.21MPa, ILSS of 23.14MPa, hardness of 85 Shore-D, and Izod impact strength of 6.56 J. Even under temperature and water aging conditions, the composites showed only minimal reductions in properties, highlighting the efficacy of the silane treatment. The temperature-aged L2 composite had a tensile strength of 104MPa, flexural strength of 172.8 MPa, compression strength of 164MPa, and ILSS of 22.5MPa, while the water-aged L2 composite exhibited a tensile strength of 96MPa, flexural strength of 152.8MPa, compression strength of 146.4MPa, and ILSS of 21.4MPa. Scanning electron microscope (SEM) analysis confirmed uniform dispersion of biosilica particles, critical for improved performance, though higher concentrations led to agglomeration and stress points. The composites also demonstrated excellent flame retardancy, maintaining a UL-94 V-0 rating with decreased flame propagation speeds, specifically 9.05mm/min for L2. These findings underscore the potential of silane-treated biosilica as a reinforcing additive to enhance the durability and performance of composites in adverse conditions.

Rotation of the cervical spine beyond its normal range of motion is a leading cause of fall-related spinal cord injuries (SCIs) in older adults. This rotation is constrained, in part, by the spinal ligaments. The experimentally measured properties of these ligaments are tabulated in literature, including sex-specific properties; however, their influence on the rotation kinematics of the cervical spine has not been compared. We examined how different mechanical properties of spinal ligaments, including sex-specific properties, affected the rotational kinematics of the cervical spine using finite element analysis (FEA). Ligament properties most influenced the rotation of the lower cervical spine, with increased ligament stiffness reducing rotation. Ligament deformation remained mostly in the toe region of their force-displacement curves, emphasizing the need to incorporate non-linear ligament behavior in FEA. Predictions made using one set of experimental properties (Property 1) better-matched experimental kinematic data. Using sex-specific properties had a moderate effect (6% in extension, –3% in flexion) on rotation, with a greater impact on extension. Ligament properties also affected the segmental distribution of rotation, causing a variability of 3–21% at different levels. We emphasized the need to incorporate tailored approaches to FEA to obtain clinically relevant results when modeling flexion/extension rotation.

An age replacement maintenance policy is considered here, in which a system is restored whenever it fails, or ages without failure up to a preventive maintenance epoch (whichever comes first). The duration of the restoration activity is random, and depends on whether it was precipitated by a failure or by a preventive maintenance action. The case where the preventive maintenance epoch is deterministic has been studied previously, and shown to be optimal in a certain sense. Here, we consider the case where the preventive maintenance epoch is randomized, which is more realistic for many systems. The system availability is the long run proportion of time that the system is operational (i.e., not undergoing repair or preventive maintenance). The optimal rate of preventive maintenance to maximize availability is considered, along with sufficient conditions for such an optimum to exist. The results obtained herein are useful to systems engineers in making critical design decisions.

For repairable systems, aging properties of the time to first failure cannot adequately reflect its degradation over time — which is influenced by repairs. For such systems, exploring notions of aging under repairs would provide a more relevant description of deterioration in performance. A framework to formulate appropriate notions of aging relative to repair strategies and examine their implications is indicated. Included among such strategies are renewals (perfect repair or, replacements) and minimal repairs, as are the repair schemes of Brown-Proschan and Block-Borges-Savits. We examine some specific notions of repair relative to aging and briefly review recent results on two aging properties under perfect repairs. The concept of efficiency of repair strategies is introduced and illustrated by simple examples. Our final results concern an induced distribution related to perfect repairs and its realizability.

The effect of thermal heat treatment on the mechanical and electrical properties of Cu–Ag alloys was investigated. The homogenization heat treatment leads to an increase in tensile strength and a decrease in electrical conductivity due to dissolution of Ag into copper matrix. Also, it is shown that electrical conductivity of as-cast Cu–Ag alloys decreases with increasing Ag content. In contrast, the aging heat treatment gives rise to increase both the tensile strength and electrical conductivity because the Ag solute diffuses out from copper matrix during aging heat treatment. Therefore, it can be mentioned that the electrical conductivity of Cu–Ag alloys depends on Ag solute in copper matrix. Also, aging treatment is favorable to acquire high strength and high electrical conductivity.

This paper investigates the impact of heat input and post-weld aging behavior at different temperatures on the laser paper welded maraging steel grade 250. Three different levels of heat inputs were chosen and CO₂ laser welding was performed. Aging was done at six different temperatures: 360${}^{\circ }$C, 400${}^{\circ }$C, 440${}^{\circ }$C, 480${}^{\circ }$C, 520${}^{\circ }$C and 560${}^{\circ }$C. The macrostructure and microstructure of the fusion zone were obtained using optical microscope. The microhardness test was performed on the weld zone. Tensile tests and impact tests were carried out for the weld samples and different age-treated weld samples. Fracture surfaces were investigated by scanning electron microscopy (SEM). Microhardness values of the fusion zone increased with increasing aging temperature, while the base metal microhardness value decreased. Tensile properties increased with aging temperature up to 480${}^{\circ }$C and reduced for 520${}^{\circ }$C and 560${}^{\circ }$C. This was mainly due to the formation of reverted austenite beyond 500${}^{\circ }$C. XRD analysis confirmed the formation of reverted austenite.

Age-related alterations of gene expression of transforming growth factor β1 (TGF-β1) and its receptors (TβRs) in tissues derived from rat intervertebral discs were assessed together with TGF-β1-dependent proteoglycan synthesis by the cultured disc cells. Disc tissues and cells were individually harvested from two sites of the coccygeal vertebrae, namely the nucleus pulposus (NP) and annulus fibrosus (AF), which are major distinct components of the intervertebral discs. Semi-quantitative RT-PCR analysis indicated that the level of gene expression of TGF-β1/TGF-β1 receptor type I (TβR-I) of NP decreased with age. In AF, the level of TGF-β1/TβRs gene expression did not apparently differ with age. Consistent with the RT-PCR results, stimulation of proteoglycan synthesis by TGF-β1 in NP cells decreased with age. Proteoglycan synthesis by AF cells was also stimulated by TGF-β1. However, levels of this stimulation by AF cells were identical. The present findings indicate that the genetic expression of TGF-β1/TβR-I and TGF-β1-dependent proteoglycan synthesis decreased with age in NP cells, and further suggest that a loss of proteoglycan synthesis with age in the intervertebral disc is at least in part due to the transcriptional down regulation of TGF-β1/TβR-I and decreased synthetic ability of proteoglycans in response to TGF-β1 by NP cells.

The effect of aging on long bone mechanical properties and bone formative capacity was characterized in the male Fisher 344 rat. The femurs of rats from three age groups (4 mo., 12 mo. and 28 mo.) were tested in three-point bending to determine their structural properties. The apparent material properties were then calculated by adjusting for bone geometry. Bone formation was assessed by dynamic histomorphometry of both cortical and cancellous bone as well as by Northern blot analysis for the expression of the osteoblast phenotypic proteins osteopontin (OP), osteocalcin (OC), type I collagen (COL) and alkaline phosphatase (AP). Aging resulted in a decline in the apparent material properties that was associated with a compensatory alteration of bone geometry that preserved structural strength and stiffness. Histomorphometric analysis revealed significant age-related decreases in cancellous bone volume, trabecular number and increased trabecular separation suggesting the existence of senile osteopenia in the proximal tibia of the male Fisher 344 rat. A significant decline in bone formation rate (BFR), but not mineral apposition rate, suggests that a reduction in osteoblast number, but not osteoblast activity, contributes to age-related bone loss. The decline in BFR with aging was reflected in a decreased mRNA expression for OP, OC and COL but not AP. Further, the pattern of mRNA expression was consistent with reduced osteoblast differentiation with aging. The present study indicates the age-related decline in material properties of long bones is paralleled by a decrease in osteogenesis.

The purposes of this study were to investigate the activation of neck muscles during movement of the head from the neutral position to the maximum points and back to the neutral position. The experiment was designed to compare between groups. There were in total 26 subjects: 11 in the young group (mean age 24.3 years old) and 15 in the middle-age group (mean age 55.9 years old) were recruited. The active ROM, velocity, and surface EMG activities of the left and right sternocleidomastoid (SCM) muscles were recorded during repetitive cervical movements in the six directions of flexion/extension, right/left rotation and side-bending. The data were evaluated with repeated-measures analysis of variance (ANOVA). The active ROM and maximum force in both flexion and extension were significantly lower for the middle-age group than for the young group. However, the integrated EMG values for the left and right SCM muscles during movement of the head to and from the maximum points of the ROM in three cardinal planes were significantly greater in the middle-age group than in the young group. Whether these over-activation of SCM is related to degeneration of the cervical spines requires further investigation.

Purpose: The aim of this study is to investigate deterioration in mechanical integrity of the collagen network of bovine bone formed by non-enzymatic glycation (NEG), a process that mimics aging by microindentation technique. Methods: Young and old bovine cortical bone specimens were rested in solutions for four weeks for the process of NEG and were grouped as ribosylated and non-ribosylated. A series of indentations were made on bone specimens weekly for each of 3-masses of 50 g, 100 g and 200 g for 10 s to detect the effect of indentation load and for each of five durations of 5 s, 10 s, 20 s, 30 s for 100 g to study the effect of indentation duration. The applied load was increased to 300 g, 500 g, 1000 g and 2000 g for 10 s to be able to make microcracks. Specimens were tested in the wet and dry state to study the effects of hydration on microhardness measurement. Results: Loads of 50 g, 100 g and 200 g for 10 s were able to differ ribosylated bone from non-ribosylated bone for the young and old bovine bones. Microhardness values increased with increasing incubation period. Microhardness of dry specimens were found to be statistically higher than that of wet specimens. Presence of extrinsic toughening mechanisms including crack bridging due to uncracked ligaments and collagen fibers were directly observed by scanning electron microscope (SEM). Ribosylated bone was found to have lower number of collagen bridging compared to non-ribosylated bovine bone. Conclusion: Microhardness test by these are able to discriminate non-modified collagen structure from modified collagen. On the other hand, it is found that microindentation was not able to discriminate the degree of NEG.

The clinical application of stem cells in hematopoietic disease.

Use of pluripotent stem cells and their differentiated products in pharmacological drug discovery and safety testing.

Messages from the nucleus: Insights into Aging.

inStem: The Institute for Stem Cell Biology and Regenerative Medicine.

Yak genome provides new insights into high altitude adaptation.

Gentris and Shanghai Institutes of Preventative Medicine expand collaboration.

Chinese researchers identify rice gene enhancing quality, productivity.

Quintiles opens new Center of Excellence in Dalian to support innovative drug development.

BGI demonstrated genomic data transfer at nearly 10 gigabits per second between US and China.

Quintiles deepens investment in China - New Quintiles China Headquarters and local lab testing solution announced.

Beike earns AABB Accreditation for cord blood and cord tissue banking.

Epigenomic differences between newborns and centenarians provide insight to the understanding of aging.

Biotechnology unveils secrets of Chinese medicine.

Climate change a mixed blessing for wheat, say experts.

NTOU identified germ cells and somatic cells in coral bodies for the first time in the world.

Researchers tabulate disturbing changes and disappearance in biodiversity in Southern Taiwan coral reefs over last 26 years.

NCKU research team discovers new complex in treating cancer.

Chinese scientists successfully crack the genome of diploid cotton.

Taiwan's healthcare market boosted by aging population.

Researchers develop mouse model of common motor neuron disease pinpointing TDP-43 protein as likely cause.

INDIA – Oral chlorea vaccine ‘offers protection for five years’.

JAPAN – Gene discovery leads way to more rice.

MALAYSIA – Top international hospitals to hold summit in Asia to address efficiency, patient safety issues.

SINGAPORE – Study led by NUS scientists provides new insights into cause of human neurodegenerative disease.

SINGAPORE – Recycled plastic proves effective in killing drug-resistant fungi.

SINGAPORE – Singapore scientists engineer human stem cells and move closer to mastering regenerative medicine.

SINGAPORE – A*STAR scientists discover novel hormone essential for heart development.

SINGAPORE – New discovery on how skin cells form “bridges” paves the way for advances in wound healing and tissue engineering.

AUSTRALIA – Pathogen study explores blocking effect of E. coli protein on immune system.

CANADA – Alzheimer's risk gene may begin to affect brains as early as childhood.

EUROPE – Simple blood test detects 85% of colorectal cancers and over 50% of polyps.

JERUSALEM – New compound for slowing the aging process can lead to novel treatments for brain diseases.

US – Older mice fed wolfberries show reduced risk for flu virus with vaccine diseases.

US – Molecular sensor detects early signs of multiple sclerosis, Gladstone study finds.

US – Scripps Research Institute scientists achieve detailed picture of key part of Hepatitis C virus.

US – Researchers discover promising new treatment to help people with spine injuries walk better.

US – Personalized vaccine for most lethal type of brain tumor shows promise.

Is Aging a Risk Factor for Cancer?

Adverse Effects of Substance Abuse on Aging: Implication of Brain Cell Injury

Diabetes and the Elderly

The Necessity for Early Therapeutic Interventions in Dementia: The Role of Neurosteroids

Indian Pharma Industry: Trends, Predictions and Challenges.

RFID Smart Sensing.

Rational Design for the Next Generation of Vaccines.

Is Aging a Risk Factor for Cancer?

China's Synthetic Biology Research.

Ethical Responsibility to Manage Incidental Findings in Brain Imaging Research.

Translating Research at SingHealth: Cardiometabollic Diseases.

Universities: A Treasure Trove of Technologies.

The Increasing Need for Bioinformatics in Life Science and Biotechnology Research.

Site Mapping the Innovative Way.

New Antifungals or Old?

SINGAPORE – VIVA Foundation and NUS Launches $10 Million Cancer Research Centre for Childhood Leukaemia.

SINGAPORE – Discovery Paves the Way for Potential Genetics-Guided Precision Medicine for Paediatric Leukaemia Patients.

SINGAPORE – Partnership between Sony and Alder Hey Children's Hospital Drives Innovation in Children's Healthcare.

UNITED STATES – UGA Researchers Make Link between Genetics and Aging.

UNITED STATES – Latin Dancing may Have Health Benefits for Older Adults.

UNITED STATES – Interferon Not Beneficial for Most Stage III Melanoma.

UNITED STATES – Dissecting the Animal Diet, Past and Present.

UNITED STATES – Water Conservation Important to Many; Only Some Take Action.

UNITED KINGDOM – Innova Biosciences Introduces New LATEX One-Step Conjugation Kits.

UNITED KINGDOM – New Understanding of the Mechanism of Neurodegeneration Leads to a Novel Approach to Treatment for Alzheimer's Disease.

TAIWAN – Breakthrough in Homogeneous Antibody Development and a New Generation of Glycoarray Technology.

TAIWAN – Increasing Protein Synthesis by Leucine Ameliorates Synaptopathy Caused by Dementia, ALS and Autism.

Current and Emerging Diagnostic and Therapeutic Developments in Age-Related Macular Degeneration (AMD).

International Collaborative Research Program focusing on Aging.

Anterior Segment Optical Coherence Tomography Angiography (OCTA).

Clinical Trials in our Real World.

Ophthalmology Workforce Planning and Projection – A New Integrated Approach.

Genetic mechanism behind aging rate uncovered.

China launches survey of endangered porpoises in Yangtze River.

Academic institutes and companies join forces to boost precision nutrition research.

Gigantic DNA database to be built in Nanjing.

Home test kit for cervical screening developed by BGI.

Chinese HPV vaccine gets permission for clinical testing.

Ineffective baby vaccines by two companies recalled.

Robot scores high result on national doctor qualification test.

Head transplant ‘never’ to be allowed.

China ranks second in Global Science Innovation.

Veolia to support Danone Nutricia Wuxi plant in China.

Chinese drug delivery devices market to reach USD638.4 million by 2023.

Brain aging in ASEAN.

What value-based healthcare means for Asia.

Improve healthcare access to tackle Asia’s healthcare challenge.