Search results for: surface aging features
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10642

Search results for: surface aging features

10582 The Importance of Clinicopathological Features for Differentiation Between Crohn's Disease and Ulcerative Colitis

Authors: Ghada E. Esheba, Ghadeer F. Alharthi, Duaa A. Alhejaili, Rawan E. Hudairy, Wafaa A. Altaezi, Raghad M. Alhejaili

Abstract:

Background: Inflammatory bowel disease (IBD) consists of two specific gastrointestinal disorders: ulcerative colitis (UC) and Crohn's disease (CD). Despite their distinct natures, these two diseases share many similar etiologic, clinical and pathological features, as a result, their accurate differential diagnosis may sometimes be difficult. Correct diagnosis is important because surgical treatment and long-term prognosis differ from UC and CD. Aim: This study aims to study the characteristic clinicopathological features which help in the differential diagnosis between UC and CD, and assess the disease activity in ulcerative colitis. Materials and methods: This study was carried out on 50 selected cases. The cases included 27 cases of UC and 23 cases of CD. All the cases were examined using H& E and immunohistochemically for bcl-2 expression. Results: Characteristic features of UC include: decrease in mucous content, irregular or villous surface, crypt distortion, and cryptitis, whereas the main cardinal histopathological features seen in CD were: epitheloid granuloma, transmural chronic inflammation, absence of mucin depletion, irregular surface, or crypt distortion. 3 cases of UC were found to be associated with dysplasia. UC mucosa contains fewer Bcl-2+ cells compared with CD mucosa. Conclusion: This study using multiple parameters such clinicopathological features and Bcl-2 expression as studied by immunohistochemical stain, helped to gain an accurate differentiation between UC and CD. Furthermore, this work spotted the light on the activity and different grades of UC which could be important for the prediction of relapse.

Keywords: Crohn's disease, dysplasia, inflammatory bowel disease, ulcerative colitis

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10581 Development of Rh/Ce-Zr-La/Al2O3 TWCs’ Wash Coat: Effect of Reactor on Catalytic and Thermal Stability

Authors: Su-Ning Wang, Yao-Qiang Chen

Abstract:

The CeO2-ZrO2-La2O3-Al2O3 composite oxides are synthesized using co-precipitation method by two different reactors (i.e. continuous stirred-tank reactor and batch reactor), and the corresponding Rh-only three-way catalysts are obtained by wet-impregnation approach. The textural, structural, morphology and redox properties of the support materials, as well as the catalytic performance of the Rh-only catalyst are investigated systematically. The results reveal that the materials (CZLA-C) synthesized by continuous stirred-tank reactor have a better physic-chemical properties than the counterpart material (CZLA-B) prepared by batch reactor. After aging treatment at 1000 ℃ for 5 h, the BET surface area and pore volume of S1 reach up to 76 m2 g-1 and 0.36 mL/g, respectively, which is higher than that of S2. The XRD and Raman results demonstrate that a high structural stability is obtained by S1 because of the negligible lattice variation and the slight grain growth after aging treatment. The SEM and TEM images display that the morphology of S1 is assembled by many homogeneous primary nanoparticles (about 6.12 nm) that are connected to form mesoporous structure The TPR measurement shows that S1 possesses a higher reduction ability than S2. Compared with the catalyst supported on the CZLA-B, the as-prepared CZLA-C demonstrates an improved three-way catalytic activity both before and after aging treatment.

Keywords: composite oxides, reactor, catalysis, catalytic performance

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10580 Multiresolution Mesh Blending for Surface Detail Reconstruction

Authors: Honorio Salmeron Valdivieso, Andy Keane, David Toal

Abstract:

In the area of mechanical reverse engineering, processes often encounter difficulties capturing small, highly localized surface information. This could be the case if a physical turbine was 3D scanned for lifecycle management or robust design purposes, with interest on eroded areas or scratched coating. The limitation partly is due to insufficient automated frameworks for handling -localized - surface information during the reverse engineering pipeline. We have developed a tool for blending surface patches with arbitrary irregularities into a base body (e.g. a CAD solid). The approach aims to transfer small surface features while preserving their shape and relative placement by using a multi-resolution scheme and rigid deformations. Automating this process enables the inclusion of outsourced surface information in CAD models, including samples prepared in mesh handling software, or raw scan information discarded in the early stages of reverse engineering reconstruction.

Keywords: application lifecycle management, multiresolution deformation, reverse engineering, robust design, surface blending

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10579 Surface Roughness Formed during Hybrid Turning of Inconel Alloy

Authors: Pawel Twardowski, Tadeusz Chwalczuk, Szymon Wojciechowski

Abstract:

Inconel 718 is a material characterized by the unique mechanical properties, high temperature strength, high thermal conductivity and the corrosion resistance. However, these features affect the low machinability of this material, which is usually manifested by the intense tool wear and low surface finish. Therefore, this paper is focused on the evaluation of surface roughness during hybrid machining of Inconel 718. The primary aim of the study was to determine the relations between the vibrations generated during hybrid turning and the formed surface roughness. Moreover, the comparison of tested machining techniques in terms of vibrations, tool wear and surface roughness has been made. The conducted tests included the face turning of Inconel 718 with laser assistance in the range of variable cutting speeds. The surface roughness was inspected with the application of stylus profile meter and accelerations of vibrations were measured with the use of three-component piezoelectric accelerometer. The carried out research shows that application of laser assisted machining can contribute to the reduction of surface roughness and cutting vibrations, in comparison to conventional turning. Moreover, the obtained results enable the selection of effective cutting speed allowing the improvement of surface finish and cutting dynamics.

Keywords: hybrid machining, nickel alloys, surface roughness, turning, vibrations

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10578 Inhibition of Variant Surface Glycoproteins Translation to Define the Essential Features of the Variant Surface Glycoprotein in Trypanosoma brucei

Authors: Isobel Hambleton, Mark Carrington

Abstract:

Trypanosoma brucei, the causal agent of a range of diseases in humans and livestock, evades the mammalian immune system through a population survival strategy based on the expression of a series of antigenically distinct variant surface glycoproteins (VSGs). RNAi mediated knockdown of the active VSG gene triggers a precytokinesis cell cycle arrest. To determine whether this phenotype is the result of reduced VSG transcript or depleted VSG protein, we used morpholino antisense oligonucleotides to block translation of VSG mRNA. The same precytokinesis cell cycle arrest was observed, suggesting that VSG protein abundance is monitored closely throughout the cell cycle. An inducible expression system has been developed to test various GPI-anchored proteins for their ability to rescue this cell cycle arrest. This system has been used to demonstrate that wild-type VSG expressed from a T7 promoter rescues this phenotype. This indicates that VSG expression from one of the specialised bloodstream expression sites (BES) is not essential for cell division. The same approach has been used to define the minimum essential features of a VSG necessary for function.

Keywords: bloodstream expression site, morpholino, precytokinesis cell cycle arrest, variant surface glycoprotein

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10577 Multi-Omics Investigation of Ferroptosis-Related Gene Expression in Ovarian Aging and the Impact of Nutritional Intervention

Authors: Chia-Jung Li, Kuan-Hao Tsui

Abstract:

As women age, the quality of their oocytes deteriorates irreversibly, leading to reduced fertility. To better understand the role of Ferroptosis-related genes in ovarian aging, we employed a multi-omics analysis approach, including spatial transcriptomics, single-cell RNA sequencing, human ovarian pathology, and clinical biopsies. Our study identified excess lipid peroxide accumulation in aging germ cells, metal ion accumulation via oxidative reduction, and the interaction between ferroptosis and cellular energy metabolism. We used multi-histological prediction of ferroptosis key genes to evaluate 75 patients with ovarian aging insufficiency and then analyzed changes in hub genes after supplementing with DHEA, Ubiquinol CoQ10, and Cleo-20 T3 for two months. Our results demonstrated a significant increase in TFRC, GPX4, NCOA4, and SLC3A2, which were consistent with our multi-component prediction. We theorized that these supplements increase the mitochondrial tricarboxylic acid cycle (TCA) or electron transport chain (ETC), thereby increasing antioxidant enzyme GPX4 levels and reducing lipid peroxide accumulation and ferroptosis. Overall, our findings suggest that supplementation intervention significantly improves IVF outcomes in senescent cells by enhancing metal ion and energy metabolism and enhancing oocyte quality in aging women.

Keywords: multi-omics, nutrients, ferroptosis, ovarian aging

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10576 The Effect of Chemical Degradation of a Nonwoven Filter Media Membrane in Polyester

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

Abstract:

The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester non-woven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibers. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

Procedia PDF Downloads 312
10575 Estimation of Forces Applied to Forearm Using EMG Signal Features to Control of Powered Human Arm Prostheses

Authors: Faruk Ortes, Derya Karabulut, Yunus Ziya Arslan

Abstract:

Myoelectric features gathering from musculature environment are considered on a preferential basis to perceive muscle activation and control human arm prostheses according to recent experimental researches. EMG (electromyography) signal based human arm prostheses have shown a promising performance in terms of providing basic functional requirements of motions for the amputated people in recent years. However, these assistive devices for neurorehabilitation still have important limitations in enabling amputated people to perform rather sophisticated or functional movements. Surface electromyogram (EMG) is used as the control signal to command such devices. This kind of control consists of activating a motion in prosthetic arm using muscle activation for the same particular motion. Extraction of clear and certain neural information from EMG signals plays a major role especially in fine control of hand prosthesis movements. Many signal processing methods have been utilized for feature extraction from EMG signals. The specific objective of this study was to compare widely used time domain features of EMG signal including integrated EMG(IEMG), root mean square (RMS) and waveform length(WL) for prediction of externally applied forces to human hands. Obtained features were classified using artificial neural networks (ANN) to predict the forces. EMG signals supplied to process were recorded during only type of muscle contraction which is isometric and isotonic one. Experiments were performed by three healthy subjects who are right-handed and in a range of 25-35 year-old aging. EMG signals were collected from muscles of the proximal part of the upper body consisting of: biceps brachii, triceps brachii, pectorialis major and trapezius. The force prediction results obtained from the ANN were statistically analyzed and merits and pitfalls of the extracted features were discussed with detail. The obtained results are anticipated to contribute classification process of EMG signal and motion control of powered human arm prosthetics control.

Keywords: assistive devices for neurorehabilitation, electromyography, feature extraction, force estimation, human arm prosthesis

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10574 Epigenetic Reprogramming of Aging: Reversing the Clock for Regenerative Medicine

Authors: Mohammad Ahmad Ahmad Odah

Abstract:

Aging is a complex biological process characterized by the progressive decline of physiological functions and increased vulnerability to age-related diseases. Epigenetic changes, particularly DNA methylation alterations, play a critical role in the aging process by influencing gene expression and genomic stability. This study explores the potential of epigenetic reprogramming as a strategy to reverse aging phenotypes in human fibroblasts. Using CRISPR-Cas9 gene editing and small molecule inhibitors targeting DNA methylation and histone acetylation, we successfully induced significant changes in DNA methylation and gene expression profiles. Our results demonstrate a global reduction in DNA methylation levels and the identification of differentially methylated regions (DMRs) associated with cellular senescence and DNA repair. Additionally, treated fibroblasts exhibited enhanced proliferative capacity, reduced cellular senescence, and improved differentiation potential. These findings suggest that epigenetic reprogramming could be a promising approach for regenerative medicine, offering potential therapeutic strategies to counteract age-related decline and extend healthy lifespan.

Keywords: epigenetic reprogramming, aging, regenerative medicine, DNA methylation, cellular rejuvenation, CRISPR-Cas9, senescence

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10573 Evaluation of Barium Sulfate and Its Surface Modification as Reinforcing Filler for Natural and Some Synthetic Rubbers

Authors: Mohamad Abdelfattah Ibrahim Elghrbawy

Abstract:

This work deals to evaluate barium sulfate (BS) before and after its surface modification as reinforcing filler for rubber. Barium sulfate was surface-modified using polymethacrylic acid (PMAA), the monolayer surface coverage of barium sulfate by polymethacrylic acid molecules occurred at 5.4x10-6 mol/g adsorbed amount. This amount was sufficient to reduce the sediment volume from 2.65 to 2.55 cm3/gm. Natural rubber (NR) was compounded with different concentrations of barium sulfate. The rheological characteristics of NR mixes were measured using a Monsanto Oscillating Disk Rheometer. The compounded NR was vulcanized at 142°C, and the physico-mechanical properties were tested according to the standard methods. The rheological data show that the minimum torque decreases while the maximum torque increases as the barium sulfate content increase. The physico-mechanical properties of NR vulcanizates were improved up to 50 phr/ barium sulfate loading. On the other hand, styrene–butadiene rubber (SBR) and nitrile–butadiene rubber (NBR) rubbers compounded with 50 phr/barium sulfate had good rheological and mechanical properties. Scanning electron microscope studies show surface homogeneity of rubber samples as a result of good dispersion of surface modified barium sulfate in the rubber matrix. The NR, SBR and NBR vulcanizates keep their values of mechanical properties after subjected to thermal oxidative aging at 90°C for 7 days.

Keywords: barium sulfate, natural rubber (nr), nitrile–butadiene rubber (nbr), polymethacrylic acid (pmaa), styrene–butadiene rubber (sbr), surface modification

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10572 Chemical Degradation of a Polyester Nonwoven Membrane Used in Aerosol and Drainage Filter

Authors: Rachid El Aidani, Phuong Nguyen-Tri, Toan Vu-Khanh

Abstract:

The filter media in synthetic fibre is the most geotextile materials used in aerosol and drainage filtration, particularly for buildings soil reinforcement in civil engineering due to its appropriated properties and its low cost. However, the current understanding of the durability and stability of this material in real service conditions, especially under severe long-term conditions are completely limited. This study has examined the effects of the chemical aging of a filter media in polyester nonwoven under different temperatures (50, 70 and 80˚C) and pH (2. 7 and 12). The effect of aging conditions on mechanical properties, morphology, permeability, thermal stability and molar weigh changes is investigated. The results showed a significant reduction of mechanical properties in term of tensile strength, puncture force and tearing forces of the filter media after chemical aging due to the chemical degradation. The molar mass and mechanical properties changes in different temperature and pH showed a complex dependence of material properties on environmental conditions. The SEM and AFM characterizations showed a significant impact of the thermal aging on the morphological properties of the fibres. Based on the obtained results, the lifetime of the material in different temperatures was determined by the use of the Arrhenius model. These results provide useful information to better understand phenomena occurring during chemical aging of the filter media and may help to predict the service lifetime of this material in real used conditions.

Keywords: nonwoven membrane, chemical aging, mechanical properties, lifetime, filter media

Procedia PDF Downloads 345
10571 Effect of Migrant Influx toward Betterment of Aging and Low Fertility Rate: Statistical Analyses in Japan

Authors: Sari K. Ishii

Abstract:

This study considers a wider viewpoint to connect migration studies with questions about financial capitalism, which seeks cheap, disposable labour transnationally. This study offers insight into whether the current state of immigration acceptance contributes to stabilizing the aging society of the nation in the long term or merely fulfills the ephemeral requirements of industries. The analyses in this study focused on three aspects. First, it examined how many migrants in Japan joined the labour market. Second, it analyzed the number of migrants that are aging. Third, it determined the number of dependent migrants accepted through labour migrants. The study findings raise further questions for future empirical studies to verify the schema of financial capitalism through the lens of migration. The scheme of seeking cheap, disposable labour transnationally may result in the descendants of both locals and mobilized labour becoming more unstable than the prior generations.

Keywords: migration, aging society, low fertility rate, Japan

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10570 Ageism: What Makes Older Adults Vulnerable to COVID-19

Authors: Jenny Kwon

Abstract:

Following the outbreak of the COVID-19 pandemic globally, another type of pandemic, ageism, appeared on the surface. Ageism, the stereotypes, prejudice, and discrimination directed towards others or oneself based on chronological age, has adversely impacted older adults' lives during the pandemic. In the short term, older adults struggled with health issues (e.g., high rate of infection and mortality) and experienced social disconnection (e.g., loneliness and depression). Ultimately, older adults' self-perceptions of aging, self-esteem and intergenerational relationships were negatively influenced. To closely look into the impact of ageism during the pandemic on U.S. older adults' aging process, the current study has three specific purposes. First, the study introduces a theoretical foundation (i.e., stereotype embodiment theory) in the development of ageism research. Second, the study reports on examples of ageism toward U.S. older adults manifested in the context of COVID-19. Finally, collective responsibilities and future research directions are proposed to fight against ageism.

Keywords: ageism, COVID-19, older adults, pandemic, stereotype embodiment

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10569 Effect of Aging Treatment on Tensile Properties of AZ91D Mg Alloy

Authors: Ju Hyun Won, Seok Hong Min, Tae Kwon Ha

Abstract:

Phase equilibria of AZ91D Mg alloys for nonflammable use, containing Ca and Y, were carried out by using FactSage® and FTLite database, which revealed that solid solution treatment, could be performed at temperatures from 400 to 450 °C. Solid solution treatment of AZ91D Mg alloy without Ca and Y was successfully conducted at 420 °C and supersaturated microstructure with all beta phase resolved into matrix was obtained. In the case of AZ91D Mg alloy with some Ca and Y, however, a little amount of intermetallic particles were observed after solid solution treatment. After solid solution treatment, each alloy was annealed at temperatures of 180 and 200 °C for time intervals from 1 min to 48 hrs and hardness of each condition was measured by micro-Vickers method. Peak aging conditions were deduced as at the temperature of 200 °C for 10 hrs.

Keywords: Mg alloy, AZ91D, nonflammable alloy, phase equilibrium, peak aging

Procedia PDF Downloads 426
10568 Determinants of Quality of Life Among Refugees Aging Out of Place

Authors: Jonix Owino

Abstract:

Aging Out of Place refers to the physical and emotional experience of growing older in a foreign or unfamiliar environment. Refugees flee their home countries and migrate to foreign countries such as the United States for safety. The emotional and psychological distress experienced by refugees who are compelled to leave their home countries can compromise their ability to adapt to new countries, thereby affecting their well-being. In particular, implications of immigration may be felt more acutely in later life stages, especially when life-long attachments have been made in the country of origin. However, aging studies in the United States have failed to conceptualize refugee aging experiences, more so for refugees who entered the country as adults. Specifically, little is known about the quality of life among aging refugees. Research studies on whether the quality of life varies among refugees by sociodemographic factors are limited. Research studies examining the role of social connectedness in aging refugees’ quality of life are also sparse. As such, the present study seeks to investigate the sociodemographic (i.e., age, sex, country of origin, and length of residence) and social connection factors associated with quality of life among aging refugees. The study consisted of a total of 108 participants from ages 50 years and above. The refugees represented in the study were from Bhutan, Burundi, and Somalia and were recruited from an upper Midwestern region of the United States. The participants completed an in-depth survey assessing social factors and well-being. Hierarchical regression was used for analysis. The results showed that females, older individuals, and refugees who were from Africa reported lower quality of life. Length of residence was not associated with quality of life. Furthermore, when controlling for sociodemographic factors, greater social integration was significantly associated with a higher quality of life, whereas lower loneliness was significantly associated with a higher quality of life. The results also indicated a significant interaction between loneliness and sex in predicting quality of life. This suggests that greater loneliness was associated with reduced quality of life for female refugees but not males. The present study highlights cultural variations within refugee groups which is important in determining how host communities can best support aging refugees’ well-being and develop social programs that can effectively cater to issues of aging among refugees.

Keywords: aging refugees, quality of life, social integration, migration and integration

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10567 Experimental and Theoretical Study on Hygrothermal Aging Effect on Mechanical Behavior of Fiber Reinforced Plastic Laminates

Authors: S. Larbi, R. Bensaada, S. Djebali, A. Bilek

Abstract:

The manufacture of composite parts is a major issue in many industrial domains. Polymer composite materials are ideal for structural applications where high strength-to-weight and stiffness-to-weight ratios are required. However, exposition to extreme environment conditions (temperature, humidity) affects mechanical properties of organic composite materials and lead to an undesirable degradation. Aging mechanisms in organic matrix are very diverse and vary according to the polymer and the aging conditions such as temperature, humidity etc. This paper studies the hygrothermal aging effect on the mechanical properties of fiber reinforced plastics laminates at 40 °C in different environment exposure. Two composite materials are used to conduct the study (carbon fiber/epoxy and glass fiber/vinyl ester with two stratifications for both the materials [904/04] and [454/04]). The experimental procedure includes a mechanical characterization of the materials in a virgin state and exposition of specimens to two environments (seawater and demineralized water). Absorption kinetics for the two materials and both the stratifications are determined. Three-point bending test is performed on the aged materials in order to determine the hygrothermal effect on the mechanical properties of the materials.

Keywords: FRP laminates, hygrothermal aging, mechanical properties, theory of laminates

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10566 Health Status, Perception of Self-Efficacy and Social Support of Thailand Aging

Authors: Wipakon Sonsnam, Kanya Napapongsa

Abstract:

The quantitative aim of the study; 1) health conditions, to examine the state of health of the aging, 2) perceived of self-efficacy, self-care of aging ,3) perceived of social support of the aging, 4) to examine factors associated with self-efficacy in enhancing the health and self-care when illness. 100 samples selected from communities in Dusit, Bangkok, 2014 by random sampling. The questionnaires were used to collect data have 5-point rating scale, consisting of strongly agree, agree, undecided, disagree, and strongly disagree; approved content valid by 3 experts, reliability coefficients alpha was .784 for perceived of self-efficacy, self-care of aging and .827 for perceived of social support of the aging. ST-5, 2Q used for collect mental health. The ability to engage in a daily routine was collected by Barthel ADL index. Founding, the sample group were female (68%). (33%) of them were in the age of 60-65. Most of them were married and still live with their spouse (55%) and do not work (38%). The average annual income was less than 10,000 baht supported by child. Most people think that income was adequate (49.0%) and Satisfaction (61.0%). Most of aging caring them-self, followed by them spouse (26%). Welfare of the public had supported, living for the aging (100%), followed by Join and health volunteers in communities (23%). In terms of health, (53%) of the sample group feels health was fair, hypertension was the most common health condition among sample group (68%), following by diabetes (55%). About eyesight, (42%) have visual acuity. (59.0%) do not need hearing aids. 84% have more than 20 teeth remaining, and have no problem with chewing (61%). In terms of Ability to engage in a daily routine, most of people (84%) in sample group are in type 1. (91%) of the participants don’t have bladder incontinence. For mental condition, (82%) do not have insomnia. (87%) do not have anxiety. (96%) do not have depression. However, (77%) of the sample group is facing stress. In terms of environment in home, bathroom in the home (90.0%) and floor of bathroom was slippery (91.0%). (48%) of the sample group has the skills of how to look after themselves while being sick, and how to keep up healthy lifestyle. Besides, some other factors, such as gender, age and educational background are related to the health perception. The statistical significance was <0.05. Suggestion: The instruments available to national standards such as ST-5, 2Q and Barthel ADL index. Reliability coefficients alpha was .784 for perceived of self-efficacy, self-care of aging and .827 for perceived of social support of the aging. The instrument used to collect perceived of social support must be further developed to study level of influence of social support that affect the health of elderly.

Keywords: ้health status, perception of aging, self-efficacy, social support

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10565 Surface and Bulk Magnetization Behavior of Isolated Ferromagnetic NiFe Nanowires

Authors: Musaab Salman Sultan

Abstract:

The surface and bulk magnetization behavior of template released isolated ferromagnetic Ni60Fe40 nanowires of relatively thick diameters (~200 nm), deposited from a dilute suspension onto pre-patterned insulating chips have been investigated experimentally, using a highly sensitive Magneto-Optical Ker Effect (MOKE) magnetometry and Magneto-Resistance (MR) measurements, respectively. The MR data were consistent with the theoretical predictions of the anisotropic magneto-resistance (AMR) effect. The MR measurements, in all the angles of investigations, showed large features and a series of nonmonotonic "continuous small features" in the resistance profiles. The extracted switching fields from these features and from MOKE loops were compared with each other and with the switching fields reported in the literature that adopted the same analytical techniques on the similar compositions and dimensions of nanowires. A large difference between MOKE and MR measurments was noticed. The disparate between MOKE and MR results is attributed to the variance in the micro-magnetic structure of the surface and the bulk of such ferromagnetic nanowires. This result was ascertained using micro-magnetic simulations on an individual: cylindrical and rectangular cross sections NiFe nanowires, with the same diameter/thickness of the experimental wires, using the Object Oriented Micro-magnetic Framework (OOMMF) package where the simulated loops showed different switching events, indicating that such wires have different magnetic states in the reversal process and the micro-magnetic spin structures during switching behavior was complicated. These results further supported the difference between surface and bulk magnetization behavior in these nanowires. This work suggests that a combination of MOKE and MR measurements is required to fully understand the magnetization behavior of such relatively thick isolated cylindrical ferromagnetic nanowires.

Keywords: MOKE magnetometry, MR measurements, OOMMF package, micromagnetic simulations, ferromagnetic nanowires, surface magnetic properties

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10564 Older Adults' Perception of Successful Aging among Unrest Situation: A Case of the Three Southernmost Provinces of Thailand

Authors: Medina Adulyarat

Abstract:

Like many other countries, Thailand is experiencing an increase in its proportion of older adults. However, the political, social, and religious climates of the various regions of Thailand are very diverse and the life experiences of older Thai citizens can vary greatly by region. For more than a decade, the southernmost provinces, namely Yala, Pattani and Narathiwat, have experienced social and political unrest, often characterized by violence in the form of bombings and shootings, which has impacted the older adults residing in these regions. While, Muslims are considered a minority in Thailand, the majority of individuals in southernmost regions are Muslims, causing these regions to be different in terms of culture and beliefs. Using a phenomenological approach, this study examines older adults’ perceptions of successful aging within the context of violent social and political unrest. This research aims to 1) understand how older adults living in these areas perceive successful aging in relation to Rowe and Kahn’s successful ageing model, and 2) describe the experiences of older adults living in areas of violent social and political unrest. Data were collected using in-depth interviews with eight older adults living in the unrest area, composing of four males and four females aged between 55-75. Content analysis was used to investigate older adults’ perception of successful aging. Older adults living their life amidst the violence did not view the situation as a threat to their life for they viewed that they are not the targets of the unrest situation. Additionally, participants identified their religious beliefs and a strong sense of community belonging as coping strategies employed to deal with social and political unrest. Thus, according to them, the violence did not affect their perception of successful aging. While the participants’ perceptions of successful aging were generally consistent with aspects identified in the successful aging model proposed by Rowe and Kahn, a theme of “financial stability” emerged. The results can be divided into four interrelated themes, which are; 1) engaging with others; 2) religiosity; 3) financial stability; and 4) health. Understanding the older persons’ view of successful aging in vulnerable situations should add more depth and enhance the conceptualization of the successful aging concept.

Keywords: cultural gerontology, minority population, successful aging, unrest situation

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10563 Processing and Modeling of High-Resolution Geophysical Data for Archaeological Prospection, Nuri Area, Northern Sudan

Authors: M. Ibrahim Ali, M. El Dawi, M. A. Mohamed Ali

Abstract:

In this study, the use of magnetic gradient survey, and the geoelectrical ground methods used together to explore archaeological features in Nuri’s pyramids area. Research methods used and the procedures and methodologies have taken full right during the study. The magnetic survey method was used to search for archaeological features using (Geoscan Fluxgate Gradiometer (FM36)). The study area was divided into a number of squares (networks) exactly equal (20 * 20 meters). These squares were collected at the end of the study to give a major network for each region. Networks also divided to take the sample using nets typically equal to (0.25 * 0.50 meter), in order to give a more specific archaeological features with some small bipolar anomalies that caused by buildings built from fired bricks. This definition is important to monitor many of the archaeological features such as rooms and others. This main network gives us an integrated map displayed for easy presentation, and it also allows for all the operations required using (Geoscan Geoplot software). The parallel traverse is the main way to take readings of the magnetic survey, to get out the high-quality data. The study area is very rich in old buildings that vary from small to very large. According to the proportion of the sand dunes and the loose soil, most of these buildings are not visible from the surface. Because of the proportion of the sandy dry soil, there is no connection between the ground surface and the electrodes. We tried to get electrical readings by adding salty water to the soil, but, unfortunately, we failed to confirm the magnetic readings with electrical readings as previously planned.

Keywords: archaeological features, independent grids, magnetic gradient, Nuri pyramid

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10562 Aging Time Effect of 58s Microstructure

Authors: Nattawipa Pakasri

Abstract:

58S (60SiO2-36CaO-4P2O5), three-dimensionally ordered macroporous bioactive glasses (3DOM-BGs) were synthesized by the sol-gel method using dual templating methods. non-ionic surfactant Brij56 used as templates component produced mesoporous and the spherical PMMA colloidal crystals as one template component yielded either three-dimensionally ordered microporous products or shaped bioactive glass nanoparticles. The bioactive glass with aging step for 12 h at room temperature, no structure transformation occurred and the 3DOM structure was produced (Figure a) due to no shrinkage process between the aging step. After 48 h time of o 3DOM structure remained and, nanocube with ∼120 nm edge lengths and nanosphere particle with ∼50 nm was obtained (Figure c, d). PMMA packing templates have octahedral and tetrahedral holes to make 2 final shapes of 3DOM-BGs which is rounded and cubic, respectively. The ageing time change from 12h, 24h and 48h affected to the thickness of interconnecting macropores network. The wall thickness was gradually decrease after increase aging time.

Keywords: three-dimensionally ordered macroporous bioactive glasses, sol-gel method, PMMA, bioactive glass

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10561 The Wear Recognition on Guide Surface Based on the Feature of Radar Graph

Authors: Youhang Zhou, Weimin Zeng, Qi Xie

Abstract:

Abstract: In order to solve the wear recognition problem of the machine tool guide surface, a new machine tool guide surface recognition method based on the radar-graph barycentre feature is presented in this paper. Firstly, the gray mean value, skewness, projection variance, flat degrees and kurtosis features of the guide surface image data are defined as primary characteristics. Secondly, data Visualization technology based on radar graph is used. The visual barycentre graphical feature is demonstrated based on the radar plot of multi-dimensional data. Thirdly, a classifier based on the support vector machine technology is used, the radar-graph barycentre feature and wear original feature are put into the classifier separately for classification and comparative analysis of classification and experiment results. The calculation and experimental results show that the method based on the radar-graph barycentre feature can detect the guide surface effectively.

Keywords: guide surface, wear defects, feature extraction, data visualization

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10560 Effect of Aging on the Second Law Efficiency, Exergy Destruction and Entropy Generation in the Skeletal Muscles during Exercise

Authors: Jale Çatak, Bayram Yılmaz, Mustafa Ozilgen

Abstract:

The second law muscle work efficiency is obtained by multiplying the metabolic and mechanical work efficiencies. Thermodynamic analyses are carried out with 19 sets of arms and legs exercise data which were obtained from the healthy young people. These data are used to simulate the changes occurring during aging. The muscle work efficiency decreases with aging as a result of the reduction of the metabolic energy generation in the mitochondria. The reduction of the mitochondrial energy efficiency makes it difficult to carry out the maintenance of the muscle tissue, which in turn causes a decline of the muscle work efficiency. When the muscle attempts to produce more work, entropy generation and exergy destruction increase. Increasing exergy destruction may be regarded as the result of the deterioration of the muscles. When the exergetic efficiency is 0.42, exergy destruction becomes 1.49 folds of the work performance. This proportionality becomes 2.50 and 5.21 folds when the exergetic efficiency decreases to 0.30 and 0.17 respectively.

Keywords: aging mitochondria, entropy generation, exergy destruction, muscle work performance, second law efficiency

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10559 Study of Age-Dependent Changes of Peripheral Blood Leukocytes Apoptotic Properties

Authors: Anahit Hakobjanyan, Zdenka Navratilova, Gabriela Strakova, Martin Petrek

Abstract:

Aging has a suppressive influence on human immune cells. Apoptosis may play important role in age-dependent immunosuppression and lymphopenia. Prevention of apoptosis may be promoted by BCL2-dependent and BCL2-independent manner. BCL2 is an antiapoptotic factor that has an antioxidative role by locating the glutathione at mitochondria and repressing oxidative stress. STAT3 may suppress apoptosis in BCL2-independent manner and promote cell survival blocking cytochrome-c release and reducing ROS production. The aim of our study was to estimate the influence of aging on BCL2-dependent and BCL2-independent prevention of apoptosis via measurement of BCL2 and STAT3 mRNAs expressions. The study was done on Armenian population (2 groups: 37 healthy young (mean age±SE; min/max age, male/female: 37.6±1.1; 20/54, 15/22), 28 healthy aged (66.7±1.5; 57/85, 12/16)). mRNA expression in peripheral blood leukocytes (PBL) was determined by RT-PCR using PSMB2 as the reference gene. Statistical analysis was done with Graph-Pad Prism 5; P < 0.05 considered as significant. The expression of BCL2 mRNA was lower in aged group (0.199) compared with young ones (0.643)(p < 0.01). Decrease expression was also recorded for female and male subgroups (p < 0.01). The expression level of STAT3 mRNA was increased (young, 0.228; aged, 0.428) (p < 0.05) during aging (in the whole age group and male/female subgroups). Decreased level of BCL2 mRNA may indicate about the suppression of BCL2-dependent prevention of apoptosis during aging in peripheral blood leukocytes. At the same time increased the level of STAT3 may suggest about activation of BCL2-independent prevention of apoptosis during aging.

Keywords: BCL2, STAT3, aging, apoptosis

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10558 The Monitoring of Surface Water Bodies from Tisa Catchment Area, Maramureş County in 2014

Authors: Gabriela-Andreea Despescu, Mădălina Mavrodin, Gheorghe Lăzăroiu, S. Nacu, R. Băstinaş

Abstract:

The Monitoring of Surface Water Bodies (Rivers) from Tisa Catchment Area - Maramureş County in 2014. This study is focused on the monitoring and evaluation of river’s water bodies from Maramureş County, using the methodology associated with the EU Water Framework Directive 60/2000. Thus, in the first part are defined the theoretical terms of monitoring activities related to the water bodies’ quality and the specific features of those we can find in the studied area. There are presented the water bodies’ features, quality indicators and the monitoring frequencies for the rivers situated in the Tisa catchment area. The results have shown the actual ecological and chemical state of those water bodies, in relation with the standard values mentioned through the Water Framework Directive.

Keywords: monitoring, surveillance, water bodies, quality

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10557 Relevant LMA Features for Human Motion Recognition

Authors: Insaf Ajili, Malik Mallem, Jean-Yves Didier

Abstract:

Motion recognition from videos is actually a very complex task due to the high variability of motions. This paper describes the challenges of human motion recognition, especially motion representation step with relevant features. Our descriptor vector is inspired from Laban Movement Analysis method. We propose discriminative features using the Random Forest algorithm in order to remove redundant features and make learning algorithms operate faster and more effectively. We validate our method on MSRC-12 and UTKinect datasets.

Keywords: discriminative LMA features, features reduction, human motion recognition, random forest

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10556 Analysis of the Role of Population Ageing on Crosstown Roads' Traffic Accidents Using Latent Class Clustering

Authors: N. Casado-Sanz, B. Guirao

Abstract:

The population aged 65 and over is projected to double in the coming decades. Due to this increase, driver population is expected to grow and in the near future, all countries will be faced with population aging of varying intensity and in unique time frames. This is the greatest challenge facing industrialized nations and due to this fact, the study of the relationships of dependency between population aging and road safety is becoming increasingly relevant. Although the deterioration of driving skills in the elderly has been analyzed in depth, to our knowledge few research studies have focused on the road infrastructure and the mobility of this particular group of users. In Spain, crosstown roads have one of the highest fatality rates. These rural routes have a higher percentage of elderly people who are more dependent on driving due to the absence or limitations of urban public transportation. Analysing road safety in these routes is very complex because of the variety of the features, the dispersion of the data and the complete lack of related literature. The objective of this paper is to identify key factors that cause traffic accidents. The individuals under study were the accidents with killed or seriously injured in Spanish crosstown roads during the period 2006-2015. Latent cluster analysis was applied as a preliminary tool for segmentation of accidents, considering population aging as the main input among other socioeconomic indicators. Subsequently, a linear regression analysis was carried out to estimate the degree of dependence between the accident rate and the variables that define each group. The results show that segmenting the data is very interesting and provides further information. Additionally, the results revealed the clear influence of the aging variable in the clusters obtained. Other variables related to infrastructure and mobility levels, such as the crosstown roads layout and the traffic intensity aimed to be one of the key factors in the causality of road accidents.

Keywords: cluster analysis, population ageing, rural roads, road safety

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10555 Development of A MG-Gd-Er-Zn-Zr Alloy with Ultrahigh Strength and Ductility via Extrusion, Pre-Deformation, and Two-Stage Aging

Authors: Linyue Jia, Wenbo Du, Zhaohui Wang, Ke Liu, Shubo Li

Abstract:

Due to the great potential for weight reduction in aerospace and automotive industries, magnesium-rare earth (Mg-RE) based alloys with outstanding mechanical performance have been widely investigated for decades. However, magnesium alloys are still restricted in engineering applications because of their lower strength and ductility. Hence, there are large spaces and challenges in achieving high-performance Mg alloys. This work reports an Mg-Gd-Er-Zn-Zr alloy with ultrahigh strength and good ductility developed via hot extrusion, pre-deformation, and two-stage aging. The extruded alloy comprises fine dynamically recrystallized (DRXed) grains and coarse worked grains with a large aspect ratio. Pre-deformation has little effect on the microstructure and macro-texture and serves primarily to introduce a large number of dislocations, resulting in strain hardening and higher precipitation strengthening during subsequent aging due to more nucleation sites. As a result, the alloy exhibits a yield strength (YS) of 506 MPa, an ultimate tensile strength (UTS) of 549 MPa, and elongation (EL) of 8.2% at room temperature, showing superior strength-ductility balance than the other wrought Mg-RE alloys previously reported. The current study proposes a combination of pre-deformation and two-stage aging to further improve the mechanical properties of wrought Mg alloys for engineering applications.

Keywords: magnesium alloys, mechanical properties, microstructure, pre-deformation, two-stage aging

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10554 Chronological Skin System Aging: Improvements in Reversing Markers with Different Routes of Green Tea Extract Administration

Authors: Aliaa Mahmoud Issa

Abstract:

Green tea may provide an alternative treatment for many skin system disorders. Intrinsic or chronological aging represents the structural, functional, and metabolic changes in the skin, which depend on the passage of time per se. The aim of the present study is to compare the effect of green tea extract administration, in drinking water or topically, on the chronological changes of the old Swiss albino mice skin. A total number of forty Swiss albino female mice (Mus musculus) were used; thirty were old females, 50-52 weeks old and the remaining ten young females were about 10 weeks old. The skin of the back of all the studied mice was dehaired with a topical depilatory cream. Treatment with green tea extract was applied in two different ways: in the drinking water (0.5mg/ml/day) or topically, applied to the skin of the dorsal side (6mg/ml water). They were divided into four main groups each of 10 animals: Group I: young untreated, Group II: old untreated groups, Group III: tea-drinking (TD) group, and Group IV: topical tea (TT) group. The animals were euthanized after 3 and 6 weeks from the beginning of green tea extract treatment. The skin was subject to morphometric (epidermal, dermal, and stratum corneum thicknesses; collagen and elastin content) studies. The skin ultrastructure of the groups treated for 6 weeks with the green tea extract was also examined. The old mouse skin was compared to the young one to investigate the chronological changes of the tissue. The results revealed that the skin of mice treated with green tea extract, either topically or to less extent in drinking water, showed a reduction in the aging features manifested by a numerical but statistically insignificant improvement in the morphometric measurements. A remarkable amelioration in the ultrastructure of the old skin was also observed. Generally, green tea extract in the drinking water revealed inconsistent results. The topical application of green tea extract to the skin revealed that the epidermal, dermal and stratum corneum thicknesses and the elastin content, that were statistically significant, approach those of the young group. The ultrastructural study revealed the same observations. The disjunction of the lower epidermal keratinocytes was reduced. It could be concluded that the topical application of green tea extract to the skin of old mice showed improvement in reversing markers of skin system aging more than using the extract in the drinking water.

Keywords: aging, green tea extract, morphometry, skin, ultrastructure

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10553 Measuring the Likeability of Robots among Seniors: A Field Research

Authors: Balaji Viswanathan, Tim Oates

Abstract:

A number of pilot projects have commenced across the world to use robots for senior care. We aim to measure the likeability of these robots among seniors and help robot designers focus on the features that matter. We built a robot likability score with over 30 parameters and used this to interview 50 seniors in various locations in the United States. This paper presents the results of this field research.

Keywords: HRI, assistive robotics, social robotics, HCI, aging

Procedia PDF Downloads 99