Search results for: fatigue crack initiation

Authors: Kodo Sektani, Apostolos Tsouvalas, Andrei Metrikine

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The reassessment of existing movable bridges in The Netherlands has created the need for acceptance/rejection criteria to assess whether the machineries are meet certain design demands. However, the existing design code defines a different limit state design, meant for new machineries which is based on a simple linear spring-mass model. Observations show that existing bridges do not confirm the model predictions. In fact, movable bridges are nonlinear systems consisting of mechanical components, such as, gears, electric motors and brakes. Next to that, each movable bridge is characterized by a unique set of parameters. However, in the existing code various variables that describe the physical characteristics of the bridge are neglected or replaced by partial factors. For instance, the damping ratio ζ, which is different for drawbridges compared to bascule bridges, is taken as a constant for all bridge types. In this paper, a model is developed that overcomes some of the limitations of existing modelling approaches to capture the dynamics of the powertrain of a class of bridge machineries First, a semidefinite dynamic model is proposed, which accounts for stiffness, damping, and some additional variables of the physical system, which are neglected by the code, such as nonlinear braking torques. The model gives an upper bound of the peak forces/torques occurring in the powertrain during emergency braking. Second, a discrete nonlinear dynamic model is discussed, with realistic motor torque characteristics during normal operation. This model succeeds to accurately predict the full time history of the occurred stress state of the opening and closing cycle for fatigue purposes.

Keywords: Dynamics of movable bridges, Bridge machinery, Powertrains, Torque measurements

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Authors: Jameson Mirimu, Edward Mawejje, Ibra Twinomujuni

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Introduction: Adolescent girls and young women (AGYW) are a vulnerable category whose risk of acquiring HIV is 20 times compared to the general population accounting for 25% of the new infections. Despite proven scientific evidence of preventing HIV acquisition, Oral Pre-Exposure Prophylaxis (PreP) is less used as one of the biomedical interventions among the AGYW. By 2020, only 31000-32000 of the targeted 90,000 persons in Uganda enrolled on Oral PreP LPHS-EC project employed a combination of Expanded Peer Outreach Approach (EPOA) and Effective client follow-up to increase PreP initiation (PrEP_NEW) and continuation for more than three months (PrEP_CT). Method: Quantitatively, data from National Key population Combination tracker retrospectively analyzed by M&E, focused group discussion with AGYWs and Health care workers to identify barriers. Barriers found; hesitancy of AGYW, misconceptions about Oral PrEP, inadequate knowledge and skills in handling adolescent and Data quality issues. To address the mentioned barriers, youth friendly corners initiated in study sites, identified PrEP Champions among the AGYW, oral PrEP dialogues, group Antenatal counselling, CQI Projects initiated, weekly perfomance meetings to track performance. Results: Routine program data review PrEP_NEW and PrEP_CT increased from 5% (4/80) and 4% (2/54), respectively, in July 2022 to 90% (72/80) and 79% (43/54) respectively for PrEP_NEW and PrEP_CT at the end of March 2023. Lessons Learnt: Demystifying misconception about oral Prep through provision of adequate information by involving health care workers through skills enhancement, CQI projects are critical intervention. Conclusion: With improved safe spaces, skills enhancement of health workers, stakeholders’ engagement through Oral Prep dialogues is critical in improving PreP uptake and continuity among the AGYWS.

Keywords: prep, uptake, continuation, AGYW

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Authors: P. Leo, E. Cerri, L. Fratini, G. Buffa

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The Friction Stir Welding process uses an inert rotating mandrel and a force on the mandrel normal to the plane of the sheets to generate the frictional heat. The heat and the stirring action of the mandrel create a bond between the two sheets without melting the base metal. As matter of fact, the use of a solid state welding process limits the insurgence of defects, due to the presence of gas in melting bath, and avoids the negative effects of materials metallurgical transformation strictly connected with the change of phase. The industrial importance of Ti-6Al-4V alloy is well known. It provides an exceptional good balance of strength, ductility, fatigue and fracture properties together with good corrosion resistance and good metallurgical stability. In this paper, the authors analyze the microstructure of friction stir welded joints of Ti-6Al-4V processed at the same travel speed (35 mm/min) but at different rotation speeds (300-500 rpm). The microstructure of base material (BM), as result from both optical microscope and scanning electron microscope analysis is not homogenous. It is characterized by distorted α/β lamellar microstructure together with smashed zone of fragmented β layer and β retained grain boundary phase. The BM has been welded in the-as received state, without any previous heat treatment. Even the microstructure of the transverse and longitudinal sections of joints is not homogeneous. Close to the top of weld cross sections a much finer microstructure than the initial condition has been observed, while in the center of the joints the microstructure is less refined. Along longitudinal sections, the microstructure is characterized by equiaxed grains and lamellae. Both the length and area fraction of lamellas increases with distance from longitudinal axis. The hardness of joints is higher than that of BM. As the process temperature increases the average microhardness slightly decreases.

Keywords: friction stir welding, microhardness, microstructure, Ti-6Al-4V

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Authors: Recep Gundogan, Turgay Dindaroglu, Hikmet Gunal, Mustafa Ulukavak, Ron Bingner

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A majority of total soil losses in agricultural areas could be attributed to ephemeral gullies caused by heavy rains in conventionally tilled fields; however, ephemeral gully erosion is often ignored in conventional soil erosion assessments. Ephemeral gullies are often easily filled from normal soil tillage operations, which makes capturing the existing ephemeral gullies in croplands difficult. This study was carried out to determine topographic features, including slope and aspect composite topographic index (CTI) and initiation points of gully channels, using images obtained from unmanned aerial vehicle (UAV) images. The study area was located in Topcu stream watershed in the eastern Mediterranean Region, where intense rainfall events occur over very short time periods. The slope varied between 0.7 and 99.5%, and the average slope was 24.7%. The UAV (multi-propeller hexacopter) was used as the carrier platform, and images were obtained with the RGB camera mounted on the UAV. The digital terrain models (DTM) of Topçu stream micro catchment produced using UAV images and manual field Global Positioning System (GPS) measurements were compared to assess the accuracy of UAV based measurements. Eighty-one gully channels were detected in the study area. The mean slope and CTI values in the micro-catchment obtained from DTMs generated using UAV images were 19.2% and 3.64, respectively, and both slope and CTI values were lower than those obtained using GPS measurements. The total length and volume of the gully channels were 868.2 m and 5.52 m³, respectively. Topographic characteristics and information on ephemeral gully channels (location of initial point, volume, and length) were estimated with high accuracy using the UAV images. The results reveal that UAV-based measuring techniques can be used in lieu of existing GPS and total station techniques by using images obtained with high-resolution UAVs.

Keywords: aspect, compound topographic index, digital terrain model, initial gully point, slope, unmanned aerial vehicle

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Authors: Nadwah Onwi, Puspa Maniam, Azmawanie A. Aziz, Fairus Mukhtar, Nor Azrita Mohamed Zin, Nurul Haslina Mohd Zin, Nurul Fatehah Ismail, Mohamad Safwan Yusoff, Susilidianamanalu Abd Rahman, Siti Munirah Harris, Maryam Aizuddin

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Objective: Malaysia has a growing number of individuals with complex communication needs (CCN). The initiation of augmentative and alternative communication (AAC) intervention may facilitate individuals with CCN to understand and express themselves optimally and actively participate in activities in their daily life. AAC is defined as multimodal use of communication ability to allow individuals to use every mode possible to communicate with others using a set of symbols or systems that may include the symbols, aids, techniques, and strategies. It is consequently critical to evaluate the deficits to inform treatment for AAC intervention. However, no known measurement tools are available to evaluate the user with CCN available locally. Design: A systematic review (SR) is designed to analyze the psychometric properties of AAC assessment for adolescents with CCN published in peer-reviewed journals. Tools are rated by the methodological quality of studies and the psychometric measurement qualities of each tool. Method: A literature search identifying AAC assessment tools with psychometrically robust properties and conceptual framework was considered. Two independent reviewers screened the abstracts and full-text articles and review bibliographies for further references. Data were extracted using standardized forms and study risk of bias was assessed. Result: The review highlights the psychometric properties of AAC assessment tools that can be used by speech-language therapists applicable to be used in the Malaysian context. The work outlines how systematic review methods may be applied to the consideration of published material that provides valuable data to initiate the development of Malay Language AAC assessment tools. Conclusion: The synthesis of evidence has provided a framework for Malaysia Speech-Language therapists in making an informed decision for AAC intervention in our standard operating procedure in the Ministry of Health, Malaysia.

Keywords: augmentative and alternative communication, assessment, adolescents, complex communication needs

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Authors: Artitaya Sabangbal, Darawan Augsornwan, Palakorn Surakunprapha, Lalida Petphai

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Background: Srinagarind Hospital Ward 3C has about 180 cases of patients with head and neck cancer per year. Almost all of these patients suffer with pain, fatigue, low self image, swallowing problem and when the tumor is larger they will have breathing problem. Many of them have complication after operation such as pressure sore, pneumonia, deep vein thrombosis. Nursing activity is very important to prevent the complication especially promoting patients early ambulation. The objective of this study was to develop early ambulation protocol for patients with head and neck cancer undergoing operation. Method: this study is one part of nursing system development in patients undergoing operation in Ward 3C. It is a participation action research divided into 3 phases Phase 1 Situation review: In this phase we review the clinical outcomes, process of care, from document such as nurses note and interview nurses, patients and family about early ambulation. Phase 2 Searching nursing intervention about early ambulation from previous study then establish protocol . This phase we have picture package of early ambulation. Phase 3 implementation and evaluation. Result: Patients with head and neck cancer after operation can follow early ambulation protocol 100%, 85 % of patients can follow protocol within 2 days after operation and 100% can follow protocol within 3 days. No complications occur. Patients satisfaction in very good level is 58% and in good level is 42% Length of hospital stay is 6 days in patients with wide excision and 16 day in patients with flap coverage. Conclusion: The early ambulation protocol is appropriate for patients with head and neck cancer who undergo operation. This can restore physical health, reduce complication and increase patients satisfaction.

Keywords: nursing system, early ambulation, head and neck cancer, operation

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Authors: Vishnu A., Ashesh Saha

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The operation of high-speed rotating machinery in industries is accompanied by rotor vibrations due to many factors. One of the primary instability mechanisms in a rotor system is the centrifugal force induced due to the eccentricity of the center of mass away from the center of rotation. These unwanted vibrations may lead to catastrophic fatigue failure. So, there is a need to control these rotor vibrations. In this work, control of rotor vibrations by using a 4-pole Radial Active Magnetic Bearing (RAMB) as an actuator is analysed. A continuous rotor system model is considered for the analysis. Several important factors, like the gyroscopic effect and rotary inertia of the shaft and disc, are incorporated into this model. The large deflection of the shaft and the restriction to axial motion of the shaft at the bearings result in nonlinearities in the system governing equation. The rotor system is modeled in such a way that the system dynamics can be related to the geometric and material properties of the shaft and disc. The mathematical model of the rotor system is developed by incorporating the control forces generated by the RAMB. A simple PD controller is used for the attenuation of system vibrations. An analytical expression for the amplitude and phase equations is derived using the Method of Multiple Scales (MMS). Analytical results are verified with the numerical results obtained using an ‘ode’ solver in-built into MATLAB Software. The control force is found to be effective in attenuating the system vibrations. The multi-valued solutions leading to the jump phenomenon are also eliminated with a proper choice of control gains. Most interestingly, the shape of the backbone curves can also be altered for certain values of control parameters.

Keywords: rotor dynamics, continuous rotor system model, active magnetic bearing, PD controller, method of multiple scales, backbone curve

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Authors: L. R. Ferreira, R. Biscaro, C. C. Danziger, C. M. Galhardi, L. C. Biscaro, R. C. Biscaro, I. S. Vasconcelos, L. C. R. Ferreira, R. Reis, L. H. Oliveira

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Introduction: There is a worldwide trend for the employer to be aware of investing in health promotion that goes beyond occupational hygiene approaches with the implementation of a comprehensive program with integration between occupational health and safety, and social/psychosocial responsibility in the workplace. Work accommodation is a necessity in most companies as it allows the worker to return to its function respecting its physical limitations. This study had the objective to verify if the integration of health and safety in the companies, with the inclusion of the concept of TWH promoted by an occupational health service has impacted in the management of absenteeism of workers in work accommodation. Method: A retrospective and paired cohort study was used, in which the impact of the implementation of the Program for the Health/Safety Integration and Total Worker Health Concept (PHSITWHC) was evaluated using the indices of absenteeism, health attestations, days and hours of sick leave of workers that underwent job accommodation/rehabilitation. This was a cohort study and the data were collected from January to September of 2017, prior to the initiation of the integration program, and compared with the data obtained from January to September of 2018, after the implementation of the program. For the statistical analysis, the student's t-test was used, with statistically significant differences being made at p < 0.05. Results: The results showed a 35% reduction in the number of absenteeism rate in 2018 compared to the same period in 2017. There was also a significant reduction in the total numbers of days of attestations/absences (mean of 2,8) as well as days of attestations, absence and sick leaves (mean of 5,2) in 2018 data after the implementation of PHSITWHC compared to 2017 data, means of 4,3 and 25,1, respectively, prior to the program. Conclusion: It can be concluded that the inclusion of the PHSITWHC was associated with a reduction in the rate of absenteeism of workers that underwent job accommodation. It was observed that, once health and safety were approached and integrated with the inclusion of the TWH concept, it was possible to reduce absenteeism, and improve worker’s quality of life and wellness, and work accommodation management.

Keywords: absenteeism, health/safety integration, work accommodation management, total worker health

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Authors: Moetazza M. Al-Shafei, Hala Abdel Karim, Eitedal M. Daoud, Hassan Zaki Hassuna

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Epilepsy is a common neurological disorder affecting all age groups. It is one of the world's most prevalent non-communicable diseases. Increased evidence suggesting that long term usage of anti-epileptic drugs can have adverse effects on bone mineralization and bone molding .Aiming to study these effects and to give guide lines to support bone health through early intervention. From Neurology Out-Patient Clinic kaser Elaini University Hospital, 60 Patients were enrolled, 40 patients on antiepileptic drugs for at least two years and 20 controls matched with age and sex, epileptic but before starting treatment both chosen under specific criteria. Patients were divided into four groups, three groups with monotherapy treated with either Phynetoin, Valporic acid or Carbamazipine and fourth group treated with both Valporic acid and Carbamazipine. Estimation of serum Carboxy-Terminal Telopeptide of Type I- Collagen(ICTP) bone resorption marker, serum 25(OH )vit D3, calcium ,magnesium and phosphorus were done .Results showed that all patients on AED had significant low levels of 25(OH) vit D3 (p<0.001) ,with significant elevation of ICTP (P<0.05) versus controls. In group treated with Phynotoin highly significant elevation of (ICTP) marker and decrease of both serum 25(OH) vit D3 (P<0, 0001) and serum calcium(P<0.05)versus control. Double drug group showed significant decrease of serum 25(OH) vit D3 (P<0.0001) and decrease in Phosphorus (P<0.05) versus controls. Serum magnesium showed no significant differences between studied groups. We concluded that Anti- epileptic drugs appears to be an aggravating factor on bone mineralization ,so therapeutically it can be worth wile to supplement calcium and vitamin D even before initiation of antiepileptic therapy. ICTP marker can be used to evaluate change in bone resorption before and during AED therapy.

Keywords: antiepileptic drugs, bone minerals, carboxy teminal telopeptidetype-1-collagen bone resorption marker, vitamin D

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Authors: Iveta Eimontaite, Sarah R. Fletcher, Michele Surico, Alfio Minissale, Fabio F. Abba

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Industry 4.0 offers possibilities for increased production volumes and greater efficiency whilst at the same time presenting new opportunities and challenges for the human workforce. Exoskeletons have been used in healthcare and are now starting to be adopted in manufacturing. The potential benefits of reducing fatigue and physical strain are attractive prospects of the technology for industry; however, the novelty of exoskeletons and surrounding ethical issues raise concerns amongst the stakeholders. The current case study investigated the introduction of an upper body exoskeleton designed to support posture but not increase physical strength in a factory over three time points: before the exoskeleton was introduced, and one and two months post-introduction once operators had experienced working with it. The main focus was to evaluate changes in operators' workload, situation awareness, technology self-efficacy, and physical discomfort following the introduction of the exoskeleton. After using the exoskeleton over two months, operators reported a decrease in temporal demand and an increase in performance of the NASA TLX instrument. Furthermore, over the second month, operators' self-reported technology self-efficacy scores increased, but at the same time, their situation awareness decreased. Interestingly, operators' physical discomfort after using the exoskeleton for two months increased from not uncomfortable to quite uncomfortable in the shoulder, arm, and middle back regions. The results suggest that self-perceived task efficiency improved; however, increased discomfort and decreased situation awareness scores indicate that two months might not be long enough for the exoskeleton to be integrated into operators’ mental body schema. The paper will discuss further implications and suggestions for exoskeleton introduction to manufacturing environments.

Keywords: exoskeleton, manufacturing, mental workload, physical discomfort, situation awareness, technology self-efficacy

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Authors: Md Mizanur Rahman, Lotanna Micah Nneji, Adeola C. Adeniyi, Edem Archibong Eniang, Abiodun B. Onadeko, Felista Kasyoka Kilunda, Babatunde E. Adedeji, Ifeanyi C. Nneji, Adiaha A. A. Ugwumba, Jie-Qiong Jin, Min-Sheng Peng, Caroline Olory, Nsikan Eninekit, Jing Che

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Nigeria contains a number of forest habitats that believed to host highly rich amphibian diversity. However, a dearth of herpetological studies has restricted information on the amphibian diversity in Nigeria. To cover the gap of knowledge, this study focused field surveys on relatively less studied forests–Afi Forest Reserve and Ikpan forest ecosystem. The goal of this study is to make a checklist and to investigate the habitat preferences of amphibians in these two forests. The study areas were surveyed between August 2018 and July 2019 following visual and acoustic methods. Individuals were identified using the morphological and molecular (16S ribosomal RNA) approach. Literature searches were conducted to document additional species that were not encountered during the current field surveys. Using the observational records and arrays of diversity indices, the patterns of species richness and abundance across habitat types were evaluated. Voucher specimens and tissue samples were deposited in the museums of the Department of Zoology, University of Ibadan Nigeria, and the remainder at the Kunming Institute of Zoology (KIZ), Chinese Academy of Sciences, Kunming, China. The result of this study revealed the presence of 30 and 31 amphibian species from the Afi Forest Reserve and the Ikpan Forest Ecosystem, respectively. There were two unidentified species from AFR and one from IFE. In total, 324 individuals of amphibian species were observed from the two study areas. Forest and swamps showed high species diversity and richness than the agricultural field and savannah. Savannah and agricultural fields had the highest similarity in the species composition. Given the increased human disturbances and consequent threats to these forests, this study offers recommendations for the initiation of conservation plans immediately.

Keywords: biodiversity, conservation, cryptic species, ecology, integrated taxonomy, species inventory

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Authors: Edward A. Osifodunrin, Jose Manuel Dias Lopes

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In Nigeria, enormous efforts/resources had, over the years, been expended on promoting financial inclusion (FI); however, it is seemingly discouraging that many of its self-declared targets on FI remained unachieved, especially amongst the Rural Dwellers and Actors in the Informal Sectors (RDAIS). Expectedly, many reasons had been earmarked for these failures: low literacy level, huge informal/rural sectors, etc. This study posits that in spite of these truly-debilitating factors, these FI policy failures could have been avoided or mitigated if the principles of active and better-managed citizens’ participation had been strictly followed in the (re)design/implementation of its FI policies. In other words, in a bid to mitigate the prevalent FE in Nigeria, this study hypothesizes the positive impact of increased/active citizens’ participation on FI outcome(s), backed by a preliminary empirical validation. Also, the study introduces the RDAIS-focused participatory financial inclusion policy (PFIP) as a major FI policy regeneration/improvement tool. The three categories of respondents that served as research subjects are FI experts in Nigeria (n = 72), RDAIS from the very rural/remote village of Unguwar Dogo in Northern Nigeria (n = 43), and RDAIS from another rural village of Sekere (n = 56) in the Southern region of Nigeria. Using survey design (5-point Likert scale questionnaires), random/stratified sampling, and descriptive/inferential statistics, the study often recorded independent consensus (amongst these three categories of respondents) that RDAIS’s active participation in iterative FI policy initiation, (re)design, implementation, (re)evaluation could indeed give improved FI outcomes. However, some questionnaire items also recorded divergent opinions and various statistically significant differences in the mean scores of these three categories. The PFIP (or any customized version of it) should then be carefully integrated into the NFIS of Nigeria (and possibly in the NFIS of other developing countries) to truly/fully provide FI policy integration for these excluded RDAIS and arrest the prevalence of FE.

Keywords: citizens’ participation, development, financial inclusion, formal financial services, national financial inclusion strategy, participatory financial inclusion policy, rural dwellers and actors in the informal sectors

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Authors: Keshav Raj Acharya, Prabina Sharma

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Sugandhakokila (Cinnamomum glaucescens Nees. Dury) is a large evergreen native tree species; mostly confined naturally in mid-hills of Rapti Zone of Nepal. The species is identified as prioritized for agro-technology development as well as for research and development by a department of plant resources. This species is band for export outside the country without processing by the government of Nepal to encourage the value addition within the country. The present study was carried out in Chillikot village of Dang district to find out the economic contribution of C. glaucescens in the local economy and to document the major conservation threats for this species. Participatory Rural Appraisal (PRA) tools such as Household survey, key informants interviews and focus group discussions were carried out to collect the data. The present study reveals that about 1.7 million Nepalese rupees (NPR) have been contributed annually in the local economy of 29 households from the collection of C. glaucescens berries in the study area. The average annual income of each family was around NPR 67,165.38 (US$ 569.19) from the sale of the berries which contributes about 53% of the total household income. Six different value chain actors are involved in C. glaucescens business. Maximum profit margin was taken by collector followed by producer, exporter and processor. The profit margin was found minimum to regional and village traders. The total profit margin for producers was NPR 138.86/kg, and regional traders have gained NPR 17/kg. However, there is a possibility to increase the profit of producers by NPR 8.00 more for each kg of berries through the initiation of community forest user group and village cooperatives in the area. Open access resource, infestation by an insect to over matured trees and browsing by goats were identified as major conservation threats for this species. Handing over the national forest as a community forest, linking the producers with the processor through organized market channel and replacing the old tree through new plantation has been recommended for future.

Keywords: community forest, conservation threats, C. glaucescens, value chain analysis

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Authors: Somayeh Negahdari, Mohsen Ghanbarzadeh, Masoud Nikbakht, Heshmatolah Tavakol

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Asthma, obesity and overweight are the main factors causing change within the heart and respiratory airways. Asthma symptoms are normally observed during exercising. Epidemiological studies have indicated asthma symptoms occurring due to certain lifestyle habits; for example, a sedentary lifestyle. In this study, eight weeks of aerobic exercises resulted in a positive effect overall in overweight women experiencing mild chronic asthma. The quasi-experimental applied research has been done based on experimental and control groups. The experimental group (seven patients) and control group (n = 7) were graded before and after the test. According to the Borg dyspnea and fatigue Perception Index, the training intensity has determined. Participants in the study performed a sub-maximal aerobic activity schedule (45% to 80% of maximum heart rate) for two months, while the control group (n = 7) stayed away from aerobic exercise. Data evaluation and analysis of covariance compared both the pre-test and post-test with paired t-test at significance level of P≤ 0.05. After eight weeks of exercise, the results of the experimental group show a significant decrease in resting heart rate, systolic blood pressure, minute ventilation, while a significant increase in maximal oxygen uptake and tolerance activity (P ≤ 0.05). In the control group, there was no significant difference in these parameters ((P ≤ 0.05). The results indicate the aerobic activity can strengthen the respiratory muscles, while other physiological factors could result in breathing and heart recovery. Aerobic activity also resulted in favorable changes in cardiovascular parameters, and exercise tolerance of overweight women with chronic asthma.

Keywords: asthma, respiratory cardiac index, exercise tolerance, aerobic, overweight

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Authors: Andrea Tonoli, Nicola Amati, Maria Cavatorta, Reza Mirsanei, Behzad Mozaffari, Hamed Ahani, Akbar Karamihafshejani, Mohammad Ghazivakili, Mohammad Abuabiah

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The vibrations transmitted to the drivers and passengers through vehicle seat seriously effect on the level of their attention, fatigue and physical health and reduce the comfort and efficiency of the occupants. Recently, some researchers have focused on vibrations at low excitation frequency(0.5-5 Hz) which are considered to be the main risk factors for lumbar part of the backbone but they were not applicable to A and B-segment cars regarding to the size and weight. A semi-active system with two symmetric negative stiffness structures (NSS) in parallel to a positive stiffness structure and actuators has been proposed to attenuate low frequency excitation and makes system flexible regarding to different weight of passengers which is applicable for A and B-Segment cars. Here, the 3 degree of freedom system is considered, dynamic equation clearly is presented, then simulated in MATLAB in order to analysis of performance of the system. The design procedure is derived so that the resonance peak of frequency–response curve shift to the left, the isolating range is increased and especially, the peak of the frequency–response curve is minimized. According to ISO standard different class of road profile as an input is applied to the system to evaluate the performance of the system. To evaluate comfort issues, we extract the RMS value of the vertical acceleration acting on the passenger's body. Then apply the band-pass filter, which takes into account the human sensitivity to acceleration. According to ISO, this weighted acceleration is lower than 0.315 m/s^2, so the ride is considered as comfortable.

Keywords: low frequency excitation, negative stiffness, seat vehicle, vibration isolation

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Authors: Nasiruddin Khan

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The increased use of caffeinated beverages and energy drink is posing threat to all ages and gender especially, younger adults. There is a lack of scientific evidence in Oman regarding caffeine and energy drink consumption. Our study aims to demonstrate the prevalence, pattern, knowledge and awareness, and side effects of caffeine intake among university students. This cross-sectional study including (N=365) apparently healthy male and female Omani university students aged 18-30 years, was carried out from February 2018-June 2018. A self-administered questionnaire with various sections was used to obtain information. The prevalence of caffeinated beverage consumption was commonly high among participants (97%). The males preferred Nescafe, coffee (both p < 0.001), espresso (p < 0.022), and soda (p < 0.008) while females consumed more tea (p < 0.029). The awareness about negative health impact of caffeine intake was significantly higher in females rather than males (p < 0.002). The overall prevalence of energy drink consumption was 42.1% (n=149), and higher in males (75%, p < 0.001). More males consumed 3-5 and > 5 cans/day while females used 1-2 cans/day. The starting age of energy drink use was higher in females (16-20 years (51.1%)) as compared to males (11-15 years (33.3%)). Females were more aware of caffeine as energy drink ingredient (p < 0.036) than males. The major source of information about enery drink was family and friends (58.3%). Red Bull was the commonly used brand (55.5%) among participants. Common reasons for high energy drink consumption were energy boost (68.4 %), taste (62.9%), reduce fatigue (52.1%), and better performance (47.3%). Females reported breathing problem, and abnormal heart beat (p < 0.004, 0.054, respectively), while more males reported irritability than females (p < 0.052). The prevalence of caffeinated beverage and energy drink consumption is high among participants. The awareness, and knowledge among university student is not satisfactory and needs immediate action to avoid excess use of such consumption.

Keywords: energy drink, caffeinated beverages, awareness, Oman

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Authors: Paula Higa

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This paper briefly examines age and its impact on a dancer’s performance career. An investigation into the possible reasons why audiences don’t regularly see veteran dancers on stage (termed as the Gray Dancer) supports the research. This analysis reflects some of the social dynamics that shape perceptions of the aging body in the U.S., as well as the correlation between the meaning of old and decay in Western culture. The primary question addressed in this research asks, who has the prerogative to determine when a dancer should stop dancing - society or the dancer themselves The aging process can significantly shorten a performer's professional career. The body has less endurance and is more susceptible to injuries, fatigue, etc. It also becomes less flexible and loses muscular strength and tone. A reduction in physical skills may usher gray dancers to embrace an ideology of shorter careers. However, in today’s age of diversity, equity, and inclusion, the realm of dance performance should reflect the times in which it is rooted; a multi-generational environment where people interact and participate in all of life's events. Overall, this study champions the inclusion of gray dancers as representations of mastery and wisdom akin to those traits associated with age and experience across various professions. Dance is an art form that transcends the assumptions of youthful beauty and physical ability. It serves as a conduit for conveying a lifetime of experiences, emotions, and ideas through the expressive vehicle of the body. Furthermore, it presents audiences with a medium to perceive and comprehend both themselves and life itself, echoing Noverre's insightful contemplation. The essay underscores the importance of valuing, sensing, and appreciating the richness that gray dancers bring to the stage by delving into segments of dance history and analyzing the possible influence of curators, directors, audiences, and society in general on ageism in dance.

Keywords: dance, ageism, politics in dance, curatorial process

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Authors: Surya Prakash Gajagouni, Akram Alfantazi, Imad Barsoum

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Austenitic stainless steels are widely recognized for their exceptional corrosion resistance and mechanical properties, rendering them indispensable materials across various industries from construction to biomedical applications. However, in chloride and high temperature atmosphere it to further enhance their surface properties, anodization has emerged as a promising surface treatment technique. Anodization modifies the surface of stainless steels by creating a protective oxide layer, improving corrosion resistance and imparting additional functional characteristics. This paper explores the structural and corrosion characteristics of anodized austenitic stainless steels (AISI 304) using a two-step anodic technique. We utilized a perchloric acid-based electrolyte followed by an ammonium fluoride-based electrolyte. This sequential approach aimed to cultivate deeper and intricately self-ordered nanopore oxide arrays on a substrate made of 304 stainless steel. Electron Microscopic (SEM and TEM) images revealed nanoporous layered structures with increased length and crack development correlating with higher voltage and anodization time. Surface composition and chemical oxidation state of surface-treated SS were determined using X-ray photoelectron spectroscopy (XPS) techniques, revealing a surface layer rich in Ni and suppressed Cr, resulting in a thin film composed of Ni and Fe oxide compared to untreated SS. Electrochemical studies demonstrated enhanced corrosion resistance in a strong alkaline medium compared to untreated SS. Understanding the intricate relationship between the structural features of anodized stainless steels and their corrosion resistance is crucial for optimizing the performance of these materials in diverse applications. This study aims to contribute to the advancement of surface engineering strategies for enhancing the durability and functionality of austenitic stainless steels in aggressive environments.

Keywords: austenitic stainless steel, anodization, nanoporous oxides, marine corrosion

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Authors: Shaher Bano, Samia Fida, Asif Israr

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The continuous development and exploitation of materials and designs have diverted the attention of the world towards the use of robust composite materials known as fiber-metal laminates in many high-performance applications. The hybrid structure of fiber metal laminates makes them a material of choice for various applications such as aircraft skin panels, fuselage floorings, door panels and other load bearing applications. The synergistic effect of properties of metals and fibers reinforced laminates are responsible for their high damage tolerance as the metal element provides better fatigue and impact properties, while high stiffness and better corrosion properties are inherited from the fiber reinforced matrix systems. They are mostly used as a layered structure in different joint configurations such as lap and but joints. The FML layers are usually bonded with each other using either mechanical fasteners or adhesive bonds. This research work is also focused on modification of an adhesive bonded joint as a single lap joint of carbon fibers based CARALL FML has been modified to increase interlaminar shear strength and avoid delamination. For this purpose different joint modification techniques such as the introduction of spews and shoulder to modify the bond shape and use of nanofillers such as carbon nano-tubes as a reinforcement in the adhesive materials, have been utilized to improve shear strength of lap joint of the adhesively bonded FML layers. Both the simulation and experimental results showed that lap joint with spews and shoulders configuration have better properties due to stress distribution over a large area at the corner of the joint. The introduction of carbon nanotubes has also shown a positive effect on shear stress and joint strength as they act as reinforcement in the adhesive bond material.

Keywords: adhesive joint, Carbon Reinforced Aluminium Laminate (CARALL), fiber metal laminates, spews

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Authors: Haobin Zheng, Xiang Zhang, Yong Shen, Hongxin Zou

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The research focuses on mode-locked fiber lasers with a non-linear amplifying loop mirror (NALM). Although these lasers have shown potential, they still have limitations in terms of low repetition rate. The self-starting of mode-locking in NALM is influenced by the cross-phase modulation (XPM) effect, which has not been thoroughly studied. The aim of this study is two-fold. First, to overcome the difficulties associated with increasing the repetition rate in mode-locked fiber lasers with NALM. Second, to analyze the influence of XPM on self-starting of mode-locking. The power distributions of two counterpropagating beams in the NALM and the differential non-linear phase shift (NPS) accumulations are calculated. The analysis is conducted from the perspective of NPS accumulation. The differential NPSs for continuous wave (CW) light and pulses in the fiber loop are compared to understand the inverse saturable absorption (ISA) mechanism during pulse formation in NALM. The study reveals a difference in differential NPSs between CW light and pulses in the fiber loop in NALM. This difference leads to an ISA mechanism, which has not been extensively studied in artificial saturable absorbers. The ISA in NALM provides an explanation for experimentally observed phenomena, such as active mode-locking initiation through tapping the fiber or fine-tuning light polarization. These findings have important implications for optimizing the design of NALM and reducing the self-starting threshold of high-repetition-rate mode-locked fiber lasers. This study contributes to the theoretical understanding of NALM mode-locked fiber lasers by exploring the ISA mechanism and its impact on self-starting of mode-locking. The research fills a gap in the existing knowledge regarding the XPM effect in NALM and its role in pulse formation. This study provides insights into the ISA mechanism in NALM mode-locked fiber lasers and its role in selfstarting of mode-locking. The findings contribute to the optimization of NALM design and the reduction of self-starting threshold, which are essential for achieving high-repetition-rate operation in fiber lasers. Further research in this area can lead to advancements in the field of mode-locked fiber lasers with NALM.

Keywords: inverse saturable absorption, NALM, mode-locking, non-linear phase shift

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Authors: Manjusha R. Vagal, Shyam K. Shrivastava, Umesh Mahantshetty, Sudeep Gupta, Supriya Chopra, Reena Engineer, Amita Maheshwari, Atul Buduk

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Vaginal stenosis is a common side effect associated with pelvic radiotherapy in cervical cancer patients which contributes negatively to woman’s health and prevents adequate vaginal/cervical examination. Vaginal dilation with a dilator is routine practice and is internationally advocated as a prophylactic measure to preserve vaginal patency. This retrospective study was carried out with the aim to know the usefulness of vaginal dilation following pelvic radiation therapy in cervical cancer patients in India. Data from medical records of 183 cervical cancer patients, which met the study criteria, were collected related to the stage of the disease, treatment received, commencement period of dilation post radiation therapy, sexual status and side effects associated to dilation practice. Data related to vaginal dimensions as per the length of insertion of a small, medium and large dilator were collected on regular follow-ups until 36 months and/or more. Vaginal dimensions as measured with the length of medium dilator insertion were used for analysis of dilation therapy results using paired t-test. Patients who underwent vaginal dilation with dilator maintained vaginal patency, also the mean vaginal length significantly increased, from 8.02 cm ± 2.69 to 9.96 ± 2.89 cm with a p value <0.001. There was no significant difference found on vaginal patency with different intervals of initiation of dilation therapy. At the third year and more following dilation therapy, significant increase in vaginal length observed with a p value of 0.0001 in both sexually active and inactive patients. Compilation of vaginal dosage during brachytherapy was inadequate, and hence, the secondary objective of the study to determine the effect of radiotherapy on the outcome of rehabilitation intervention was not studied in detail. This retrospective study has found that dilation therapy with vaginal dilators post pelvic radiotherapy is effective in preventing vaginal stenosis and improving vaginal patency and cannot be substituted with vaginal intercourse. Sexual quality of life assessment in the Indian population needs much attention.

Keywords: dilator, sexually active, vaginal dilation, vaginal stenosis

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Authors: Yaya Gao, Jifeng Liu, Yafeng Liu

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Objectives: This study aimed to improve clinicians' understanding and diagnosis of the Mammary analogue secretory carcinoma of the salivary gland（MASC）. Methods: The clinical features of a MASC patient who was admitted to WestChina Hospital of Sichuan University in July 2020 were reviewed and analyzed. A 49-year-old woman with left upper neck pain for three months was admitted to the hospital. She underwent adenoma resection of the left submandibular gland 14 years ago and mucoepidermoid carcinoma resection surgery five years ago. Three months before admission, the patient developed pain in the left mandibular angle after "fatigue" and gradually developed radiation pain in the left ear, which could be relieved after rest. A mass of 1cm could be touched at the mandibular, with tenderness, poor mobility, and hard texture. No swelling, heat, pain, rupture, or pus was found on the surrounding skin. Color doppler ultrasonography of the salivary gland indicated a weak echo mass of 23*14*17mm in the left parotid gland. Results: Surgical excision was completed. Immunohistochemistry of the tumor samples after operation showed that P63（a few，+）, CK7（+）, S100（+）, DOG1（-）, Ki67（MIB-1）（+，5%），pan-TRK（+）, PAS(+) . ETV-6 gene translocation was detected in FISH in postoperative pathology, which indicated MASC. After this diagnosis, the patient sent the postoperative specimen of the second submandibular tumor to our hospital for consultation. The morphology of the two was similar. FISH detected ETV-6 gene translocation, so the second pathological diagnosis was revised to MASC. Conclusion: MASC of the salivary gland is a rare salivary gland tumor whose diagnosis depends on the result of the ETV6-NTRK3 fusion gene.

Keywords: mammary analogue secretory carcinoma, ETV6-NTRK3, salivary gland, misdiagnosed

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Authors: Zahra Soltani Shal

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Introduction: The COVID-19 pandemic marks an extraordinary global public health crisis unseen in the last century, with its rapid spread worldwide and associated mortality burden. Healthcare resilience during a pandemic is crucial not only for continuous and safe patients care but also for control of any outbreak. Aim: The present study was conducted to discover the organizational variables effective in increasing resilience and continuing the work of nurses in critical and stressful pandemic conditions. Method: The study population is nurses working in hospitals for patients with coronavirus. Sampling was done purposefully and information was collected from 15 nurses through In-depth semi-structured interviews. The interview was conducted to analyze the data using the framework analysis method consisting of five steps and is classified in the table. Results: According to the findings through semi-structural interviews, among organizational variables, organizational commitment (Affective commitment, continuous commitment, normative commitment) has played a prominent role in nurses' resilience. Discussion: despite the non-withdrawal of nurses and their resilience, due to the negative quality of their working life, the mentioned variable has affected their level of performance and ability and leads to fatigue and physical and mental exhaustion. Implications for practice: By equipping hospitals and improving the facilities of nurses, their organizational commitment can be increased and lead to their resilience in critical situations. Supervisors and senior officials at the hospitals should be responsible for nurses' health and safety. A clear and codified program in critical situations and comprehensive management is effective in improving the quality of the work-life of nurses. Creating an empathetic and interactive environment can help promote nurses' mental health.

Keywords: organizational commitment, quality of work life, nurses resilience, pandemic, coronavirus

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Authors: Mohammad Mohammadi, Mohammad Pashmchi

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Background: Malnutrition commonly develops and worsens following gastric cancer surgery, particularly after discharge, which is associated with adverse outcomes. Former studies have primarily focused on patients during their hospital stay period, and there is limited evidence regarding the recommendation of nutritional interventions for patients after discharge from the hospital following gastric cancer surgery. This review is aimed to evaluate the efficiency of post-discharge dietary counseling with oral nutritional supplements (ONS), and dietary counseling alone on post-surgical nutritional outcomes in patients undergoing gastric cancer surgery. Methods: The four databases of Embase, PubMed, web of science, and google scholar were searched up to November 2022 for relevant randomized controlled trials. The Cochrane Collaboration’s assessment tool for randomized trials was used to evaluate the quality of studies. Results: Compared to patients who only received dietary counseling, patients who received both dietary counseling and ONS had considerably higher SMI, BMI, and less weight loss and sarcopenia occurrence rate. The patients who had received dietary counseling and ONS had significantly lower risk of chemotherapy intolerance. No differences in the readmission rate between the two groups was found. In terms of the quality of life, concomitant dietary advice and ONS significantly was associated with lower appetite loss and fatigue rate, but there was no difference in the other outcomes between the two groups. Conclusions: Post-discharge dietary advice with ONS following gastric cancer surgery may improve skeletal muscle maintenance, nutritional outcomes, quality of life variables, and chemotherapy tolerance. This evidence supports the recommendation of post-discharge dietary advice with ONS for patients who underwent gastric cancer surgery.

Keywords: gastric cancer surgery, oral nutritional supplements, malnutrition, gastric cancer

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Authors: Saba Amreen Syeda, Summaiah Asim, Syeda, Hafsa, Essam Quraishi

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Mantle Cell Lymphoma (MCL) is a relatively uncommon type of lymphoma that comprises approximately 7 percent of non hodgkin's lymphomas (NHL), Classic MCL presents mostly in lymph nodes and occasionally in extranodal sites. About 26 % of MCL is present primarily in the Gastrointestinal tract. While both the upper GI tract and the lower GI tract could be involved, it is rare to present with concurrent upper and lower GI involvement with MCL. We present the case of a 51-year-old Asian Indian male that presented to our clinic with complaints of chronic diarrhea for the last one year, progressively worsening over the past three months. The Patient also reported black stool as well as bright red blood per rectum. Patient reported severe fatigue on minimal exertion. On a physical exam, the patient was noted to have matted lymphadenopathy in the neck. Patient was noted to be anemic with a hemoglobin to be 8 g/dl. Esophagogastroduodenoscopy and colonoscopy was performed. EGD showed a large 4 cm ulcer in the gastric antrum with thick heaped up edges. There was bleeding on contact. Colonoscopy showed a large 35 mm multilobulated polyp in the ascending colon, which was biopsied. The patient was also noted to have nodular proctitis in the mid rectum. This was localized and extended to about 5 cm. This area was biopsied as well. Biopsies from the stomach, colon, as well as the rectum, returned with findings of mantle cell lymphoma on pathology. Lymphoid cells in the biopsy were stained strongly positive for CD 20, cyclin D1, and CD 5. There was the absence of stain for CD 3 and CD 10. The IHC stain for CD 23 was negative. Biopsies from neck LAD were obtained and were also positive for MCL. The patient was referred to oncology for staging and treatment.

Keywords: mantle cell lymphoma, GI bleed, diarrhea, gastric ulcer, colon polyp

Procedia PDF Downloads 126

Authors: Anthony J. Kondracki, Bonzo I. Reddick, Jennifer L. Barkin

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We sought to examine the association of maternal Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and treponema pallidum (TP) (syphilis) infections with preterm birth (PTB) (<37 weeks gestation), low birth weight (LBW) (<2500 grams) and prenatal care (PNC) attendance. This cross-sectional study was based on data drawn from the 2020 United States National Center for Health Statistics (NCHS) Natality File. We estimated the prevalence of all births, early/late PTBs, moderately/very LBW, and the distribution of sexually transmitted infections (STIs) according to maternal characteristics in the sample. In multivariable logistic regression models, we examined adjusted odds ratios (aORs) and their corresponding 95% confidence intervals (CIs) of PTB and LBW subcategories in the association with maternal/infant characteristics, PNC status, and maternal CT, NG, and TP infections. In separate logistic regression models, we assessed the risk of these newborn outcomes stratified by PNC status. Adjustments were made for race/ethnicity, age, education, marital status, health insurance, liveborn parity, previous preterm birth, gestational hypertension, gestational diabetes, PNC status, smoking, and infant sex. Additionally, in a sensitivity analysis, we assessed the association with early, full, and late term births and the potential impact of unmeasured confounding using the E-value. CT (1.8%) was most prevalent STI in pregnancy, followed by NG (0.3%), and TP (0.1%). Non-Hispanic Black women, 20-24 years old, with a high school education, and on Medicaid had the highest rate of STIs. Around 96.6% of women reported receiving PNC and about 60.0% initiated PNC early in pregnancy. PTB and LBW were strongly associated with NG infection (12.2% and 12.1%, respectively) and late initiation/no PNC (8.5% and 7.6%, respectively), and ≤10 prenatal visits received (13.1% and 10.3%, respectively). The odds of PTB and LBW were 2.5- to 3-foldhigher for each STI among women who received ≤10 prenatal visits than >10 visits. Adequate prenatal care utilization and timely screening and treatment of maternal STIs can substantially reduce the burden of adverse newborn outcomes.

Keywords: low birthweight, prenatal care, preterm birth, sexually transmitted infections

Procedia PDF Downloads 154

Authors: Safitri Nur Wulandari, M. Ivan Adi Perdana, Prathisto L. Panuntun Unggul, R. Dary Wira Mahadika

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In road construction on the soft soil, we need a soil improvement method to improve the soil bearing capacity of the land base so that the soil can withstand the traffic loads. Most of the land in Indonesia has a soft soil, where soft soil is a type of clay that has the consistency of very soft to medium stiff, undrained shear strength, Cu <0:25 kg/cm2, or the estimated value of NSPT <5 blows/ft. This study focuses on the analysis of the effect on preloading load (embarkment) to the amount of settlement ratio on the under of embarkment that will impact on the building cracks around of embarkment. The method used in this research is a superposition method for embarkment distribution on 27 locations with undisturbed soil samples at some borehole point in Java and Kalimantan, Indonesia. Then correlating the results of settlement plate monitoring on the field with Asaoka method. The results of settlement plate monitoring taken from an embarkment of Ahmad Yani airport in Semarang on 32 points. Where the value of Cc (index compressible) soil data based on some laboratory test results, while the value of Cc is not tested obtained from empirical formula Ardhana and Mochtar, 1999. From this research, the results of the field monitoring showed almost the same results with an empirical formulation with the standard deviation of 4% where the formulation of the empirical results of this analysis obtained by linear formula. Value empirical linear formula is to determine the effect of compression heap area as high as 4,25 m is 3,1209x + y = 0.0026 for the slope of the embankment 1: 8 for the same analysis with an initial height of embankment on the field. Provided that at the edge of the embankment settlement worth is not equal to 0 but at a quarter of embankment has a settlement ratio average 0.951 and at the edge of embankment has a settlement ratio 0,049. The influence areas around of embankment are approximately 1 meter for slope 1:8 and 7 meters for slope 1:2. So, it can cause the building cracks, to build in sustainable development.

Keywords: building cracks, influence area, settlement plate, soft soil, empirical formula, embankment

Procedia PDF Downloads 323

Authors: Tacho Rubby Kong

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Community health workers’ performances are known to influence members’ behaviours and practices while translating policies into service delivery. However, little remains known about the extent to which this remains true within interventions aimed at addressing malaria burden in low-resource settings like Cameroon. The objective of this study was to examine the health workers’ performance and their influence on the adoption of strategies to address the malaria burden at a subnational level health system in Cameroon. A qualitative exploratory design was adopted on a purposively selected sample of 18 key informants. The study was conducted in Konye health district among sub-national health systems, managers, health facility in-charges, and frontline community health workers. Data was collected using semi-structured interview guides in a face-to-face interview with respondents. The analysis adopted a thematic approach utilising journals, credible authors, and peer review articles for data management. Participants acknowledged that workplace networks were influential during the implementation of policies to address malaria. The influence exerted was in form of linkage with other services, caution, and advice regarding strict adherence to policy recommendations, perhaps reflective of the level of trust in providers’ ability to adhere to policy provisions. At the district health management level and among non-state actors, support in perceived areas of weak performance in policy implementation was observed. In addition, timely initiation of contact and subsequent referral was another aspect where community health workers exerted influence while translating policies to address the malaria burden. While the level of support from among network peers was observed to influence community health workers’ adoption and implementation of strategies to address the malaria burden, different mechanisms triggered subsequent response and level of adherence to recommended policy aspects. Drawing from the elicited responses, it was infer that community health workers’ performance influence the direction and extent of success in policy implementation to address the malaria burden at the subnational level.

Keywords: subnational, community, malaria, strategy

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Authors: Selvam M., Vadthya Poornachandar, Surender Singh

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These Reclaimed Asphalt Pavement (RAP) aggregates are generally dumped in the open area after the demolition of Asphalt Pavements. The utilization of RAP aggregates in cement concrete pavements may provide several socio-economic-environmental benefits and could embrace the circular economy. The cross recycling of RAP aggregates in the concrete pavement could reduce the consumption of virgin aggregates and saves the fertile land. However, the structural, as well as functional properties of RAP-concrete could be significantly lower than the conventional Pavement Quality Control (PQC) pavements. This warrants judicious selection of RAP fraction (coarse and fine aggregates) along with the accurate proportion of the same for PQC highways. Also, the selection of the RAP fraction and its proportion shall not be solely based on the mechanical properties of RAP-concrete specimens but also governed by the structural and functional behavior of the pavement system. In this study, an effort has been made to predict the optimum RAP fraction and its corresponding proportion for cement concrete pavements by considering the low-volume and high-volume roads. Initially, the effect of inclusions of RAP on the fresh and mechanical properties of concrete pavement mixes is mapped through an extensive literature survey. Almost all the studies available to date are considered for this study. Generally, Indian Roads Congress (IRC) methods are the most widely used design method in India for the analysis of concrete pavements, and the same has been considered for this study. Subsequently, fatigue damage analysis is performed to evaluate the required safe thickness of pavement slab for different fractions of RAP (coarse RAP). Consequently, the performance of RAP-concrete is predicted by employing the AASHTO-1993 model for the following distresses conditions: faulting, cracking, and smoothness. The performance prediction and total cost analysis of RAP aggregates depict that the optimum proportions of coarse RAP aggregates in the PQC mix are 35% and 50% for high volume and low volume roads, respectively.

Keywords: concrete pavement, RAP aggregate, performance prediction, pavement design

Procedia PDF Downloads 139

Authors: Rogaleva Liudmila, Malkin Valery

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Physical culture lessons are considered not only to be a means of physical development of students, but a matter of their personal development. Physical culture lessons can enable to develop such qualities of students as activity and initiation, readiness to cooperate, self-confidence, ability to define and reach targets, readiness to overcome difficulties and assess their abilities (and disadvantages) properly in any precise situation as well to be responsible for their own decision. The solution of this problem is possible under the circumstance if the students aware themselves as the subject of the activity that are able to develop their possibilities. The research was aimed to learn the matters that enable female teenagers of senior forms to become strong personalities attending physical culture lessons. There were two stages of the research. At the first stage we define the interests and demands of the girls. According the results of research we changed the programme of physical culture lessons. We took into consideration values of youth subculture: youth music, preferences to sport-dancing physical activities, demand of self-determination, revealing their individualities, needs of cooperative work. At the second stage we worked out motivating technology of course. This technology was aimed to create sush conditions under which students could show themselves as the subjects of activity and self-development. The active participation sport-dance festivals during 2-3 years creates the conditions for their self-realization. 78% students of the experimental groups considered their main motives to were: the interest, developing of their abilities, the satisfaction of the achievements of targets. Control groups 67% of the students claimed the success school good marks. The girls said that due to festivals they became self-confident (94%), responsible (86%), ability to cooperate (73%), aspiration for reaching the target (68%), self-exactingness (57 %). The main factors that provide successful performance were called: efforts to reach the target (87%), mutual support and mutual understanding (77%). The research on values showed that in the experimental groups we can find increase of importance of such values as: social initiative (active life) 83%, friends (75%), self-control (73%), effectiveness in deeds (58%).

Keywords: physical culture, subject, personal development, self-determination

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