Search results for: coping with stress
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4263

Search results for: coping with stress

1833 Population Centralization in Urban Area and Metropolitans in Developing Countries: A Case Study of Urban Centralization in Iran

Authors: Safar Ghaedrahmati, Leila Soltani

Abstract:

Population centralization in urban area and metropolitans, especially in developing countries such as Iran increase metropolitan's problems. For few decades, the population of cities in developing countries, including Iran had a higher growth rate than the total growth rate of countries’ population. While in developed countries, the development of the big cities began decades ago and generally allowed for controlled and planned urban expansion, the opposite is the case in developing countries, where rapid urbanization process is characterized by an unplanned existing urban expansion. The developing metropolitan cities have enormous difficulties in coping both with the natural population growth and the urban physical expansion. Iranian cities are usually the heart of economic and cultural changes that have occurred after the Islamic revolution in 1979. These cities are increasingly having impacts via political–economical arrangement and chiefly by urban management structures. Structural features have led to the population growth of cities and urbanization (in number, population and physical frame) and the main problems in them. On the other hand, the lack of birth control policies and the deceptive attractions of cities, particularly big cities, and the birth rate has shot up, something which has occurred mainly in rural regions and small cities. The population of Iran has increased rapidly since 1956. The 1956 and 1966 decennial censuses counted the population of Iran at 18.9 million and 25.7 million, respectively, with a 3.1% annual growth rate during the 1956–1966 period. The 1976 and 1986 decennial censuses counted Iran’s population at 33.7 and 49.4 million, respectively, a 2.7% and 3.9% annual growth rate during the 1966–1976 and 1976–1986 periods. The 1996 count put Iran’s population at 60 million, a 1.96% annual growth rate from 1986–1996 and the 2006 count put Iran population at 72 million. A recent major policy of urban economic and industrial decentralization is a persistent program of the government. The policy has been identified as a result of the massive growth of Tehran in the recent years, up to 9 million by 2010. Part of the growth of the capitally resulted from the lack of economic opportunities elsewhere and in order to redress the developing primacy of Tehran and the domestic pressures which it is undergoing, the policy of decentralization is to be implemented as quickly as possible. Type of research is applied and method of data collection is documentary and methods of analysis are; population analysis with urban system analysis and urban distribution system

Keywords: population centralization, cities of Iran, urban centralization, urban system

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1832 Orthosis and Finite Elements: A Study for Development of New Designs through Additive Manufacturing

Authors: M. Volpini, D. Alves, A. Horta, M. Borges, P. Reis

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The gait pattern in people that present motor limitations foment the demand for auxiliary locomotion devices. These artifacts for movement assistance vary according to its shape, size and functional features, following the clinical applications desired. Among the ortheses of lower limbs, the ankle-foot orthesis aims to improve the ability to walk in people with different neuromuscular limitations, although they do not always answer patients' expectations for their aesthetic and functional characteristics. The purpose of this study is to explore the possibility of using new design in additive manufacturer to reproduce the shape and functional features of a ankle-foot orthesis in an efficient and modern way. Therefore, this work presents a study about the performance of the mechanical forces through the analysis of finite elements in an ankle-foot orthesis. It will be demonstrated a study of distribution of the stress on the orthopedic device in orthostatism and during the movement in the course of patient's walk.

Keywords: additive manufacture, new designs, orthoses, finite elements

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1831 Evaluation of Drained Shear Strength of Bentonite-Sand Mixtures

Authors: Navid Khayat

Abstract:

Drained shear strength of saturated soils is fully understood. Shear strength of unsaturated soils is usually expressed in terms of soil suction. Evaluation of shear strength of compacted mixtures of sand-bentonite at optimum water content is main purpose of this research. To prepare the required samples, first, bentonite and sand are mixed in 10, 30, 50 and 70 percent by dry weight and then compacted at the proper optimum water content according to the standard proctor test. The samples were sheared in direct shear machine. Stress-strain relationship of samples indicated a ductile behavior. Most of the samples showed a dilatancy behavior during the shear and the tendency for dilatancy increased with the increase in sand proportion. The results show that with the increase in percentage of sand a decrease in cohesion intercept c' for mixtures and an increase in the angle of internal friction Φ’is observed.

Keywords: bentonite, sand, drained shear strength, cohesion intercept

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1830 Influence of Urban Design on Pain and Disability in Women with Chronic Low Back Pain in Urban Cairo

Authors: Maha E. Ibrahim, Mona Abdel Aziz

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Background: Chronic low back pain (CLBP) in urban communities represents a challenge to healthcare systems worldwide. The traditional biomedical approach to back pain has been particularly inadequate. Failure of the biomedical model to explain the poor correlation between pain and disability on the one hand, and biological and physical factors that explain those symptoms on the other has led to the adoption of the biopsychosocial model, to recognize the reciprocal influence of physical, social and psychological factors implicated in CLBP, a condition that shows higher prevalence among women residing in urban areas. Urban design of the built community has been shown to exert a significant influence on physical and psychological health. However, little research has investigated the relationship between elements of the built environment, and the level of pain and disability of women with CLBP. As Egypt embarks on building a new capital city, and new settlements proliferate, better understanding of this relationship could greatly reduce the economic and human costs of this widespread medical problem for women. Methods: This study was designed as an exploratory mixed qualitative and quantitative study. Twenty-Six women with CLBP living in two neighborhoods in Cairo, different in their urban structure, but adjacent in their locations (Old Maadi and New Maadi) were interviewed using semi-structured interviews (8 from Old Maadi and 18 from New Maadi). Located in the South of Cairo, New Maadi is a neighborhood with the characteristic modern urban style (narrow streets and tall, adjacent buildings), while Old Maadi is known for being greener, quieter and more relaxed than the usual urban districts of Cairo. The interviews examined their perceptions of the built environment, including building shapes and colors and street light, as well as their sense of safety and comfort, and how it affects their physical and psychological health in general, and their back condition in particular. In addition, they were asked to rate their level of pain and to fill the Oswestry Disability Index (ODI), and the General Health Questionnaire (GHQ-12) to rate their level of disability and psychological status, respectively. Results: Women in both districts had moderate to severe pain and moderate disability with no significant differences between the two districts. However, those living in New Maadi had significantly worse scores on the GHQ-12 than those living in Old Maadi. Most women did not feel that specific elements of the built environment affected their back pain, however, they expressed distress of the elements that were ugly, distorted or damaged, especially where there were no ways of avoiding or fixing them. Furthermore, most women affirmed that the unsightly and uncomfortable elements of their neighborhoods affected their mood states and were a constant source of stress. Conclusion: This exploratory study concludes that elements of the urban built environment do not exert a direct effect on CLBP. However, the perception of women regarding these elements does affect their mood states, and their levels of stress, making them a possible indirect cause of increased suffering in these women.

Keywords: built environment, chronic back pain, disability, urban Cairo

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1829 Chronic Exposure of Mercury on Amino Acid Level in Freshwater Fish Clarias batrachus (Linn.)

Authors: Mary Josephine Rani

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Virtually all metals are toxic to aquatic organisms because of the devastating effect of these metals on humans; heavy metals are one of the most toxic forms of aquatic pollution. Metal concentrations in aquatic organisms appear to be of several magnitudes higher than concentrations present in the ecosystem. Mercury is one of the most toxic heavy metals in the environment. The principal sources of contamination in wastewater are chloralkali plants, battery factories, mercury switches, and medical wastes. Elevated levels of mercury in aquatic organisms specially fish represent both an ecological and human concern. Amino acid levels were estimated in five tissues (gills, liver, kidney, brain and muscle) of Clariasbatrachus after 28 days of chronic exposure to mercury. Free amino acids serve as precursor for energy production under stress and for the synthesis of required proteins to face the metal challenge.

Keywords: amino acids, fish, mercury, toxicity

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1828 Evaluation of Potential Production of Maize Genotypes of Early Maturity in Rainfed Lowland

Authors: St. Subaedah, A. Takdir, Netty, D. Hidrawati

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Maize development at the rainfed lowland after rice is often confronted with the occurrence of drought stress at the time of entering the generative phase, which will cause be hampered crop production. Consequently, in the utilization of the rainfed lowland areas optimally, an effort that can be done using the varieties of early maturity to minimize crop failures due to its short rainy season. The aim of this research was evaluating the potential yield of genotypes of candidates of maize early maturity in the rainfed lowland areas. The study was conducted during May to August 2016 at South Sulawesi, Indonesia. The study used randomized block design to compare 12 treatments and consists of 8 genotypes namely CH1, CH2, CH3, CH4, CH5, CH6, CH7, CH8 and the use of four varieties, namely Bima 3, Bima 7, Lamuru and Gumarang. The results showed that genotype of CH2, CH3, CH5, CH 6, CH7 and CH8 harvesting has less than 90 days. There are two genotypes namely genotypes of CH7 and CH8 that have a fairly high production respectively of 7.16 tons / ha and 8.11 tons/ ha and significantly not different from the superior varieties Bima3.

Keywords: evaluation, early maturity, maize, yield potential

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1827 The Experiences of Rural Family Caregivers of Cancer Patients in Newfoundland and Labrador and Their Challenges and Needs in Relocating to Urban Settings for Treatment

Authors: Mei Li, Victor Meddalena

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Background: Newfoundland and Labrador (NL) has rapidly aging population and is characterized by its vast geography with high proportion of dispersed rural communities when compared to other provinces in Canada. Structural, demographic and geographic factors have created big gaps for rural residents across NL with respect to accessing various health and social services. While the barriers are well documented for patients’ access to cancer care in rural and remote areas, challenges faced by family caregivers are not fully recognized. Caregiving burden coupled with challenges associated with relocation and frequent travels create situations where caregivers are vulnerable physically, emotionally, financially and socially. This study examines the experiences of family caregivers living in rural NL through a social justice lens. It is expected to identify the gaps existing in social policy and support for rural family caregivers. It will make a novel contribution to the literature in this regard. Methods: Design: This qualitative study adopted the hermeneutic phenomenology to best describe and interpret rural-based family caregivers’ living experiences and explore the meaning, impact, and the influence of both individual experience and contextual factors shaping these experiences. Data Collection: In-depth interviews with key informants were conducted with 12 participants from various rural communities in NL. A case study was also used to explore an individual’s experience in complex social units consisting of multiple variables of in-depth understanding of the reality. Data Analysis: Thematic analysis guided by the Voice-Centred Relational (VCR) method was employed to explore the relationships and contexts of participants. Emerging Themes: Six major emerging themes were identified, namely, overwhelming caregiving burden on rural family caregivers, long existing financial hardship, separation from family and community, low level of social support and self-reliance coping strategies, and social vulnerability and isolation. Conclusion: Understanding the lived experiences of rural-based family caregivers is critical to inform the policy makers the gap of health and social service in NL. The findings of this study also have implications for family caregivers who are vulnerable in other similar contexts. This study adds innovative insights for policy making and service provision in this regard.

Keywords: family caregivers, policy, relocation, rural

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1826 A Systematic Review on Communication and Relations between Health Care Professionals and Patients with Cancer in Outpatient Settings Matter

Authors: Anne Prip, Kirsten Alling Møller, Dorte Lisbet Nielsen, Mary Jarden, Marie-Helene Olsen, Anne Kjaergaard Danielsen

Abstract:

Background: The development in cancer care has shifted towards shorter hospital stays and more outpatient treatment. Today, cancer care and treatment predominantly takes place in outpatient settings where encounters between patients and health care professionals are often brief. This development will probably continue internationally as the global cancer burden seems to be growing significantly. Furthermore, the number of patients who require ambulatory treatments such as chemotherapy is increasing. Focusing on the encounters between health care professionals and patients during oncology treatment has thus become increasingly important due to a growing trend in outpatient cancer management. Objective: The aim of the systematic review was to summarize the literature from the perspective of the patient, on experiences of and the need for communication and relationships with the health care professional during chemotherapy treatment in an outpatient setting. Method: The review was designed and carried out according to the PRISMA guidelines and PICO framework. The systematic search was conducted in Medline, CINAHL, The Cochrane Library and Joanna Briggs Institute Evidence Based Practice Database. Results: In all, 1174 studies were identified by literature search. After duplicates were removed, the remaining studies (n = 1053) were screened for inclusion. Nine studies were included; qualitative (n = 5) and quantitative (n = 4) as they met the inclusions criteria. The review identified that communication and relationships between health care professionals and patients were important for the patients’ ability to cope with cancer and also had an impact on patients’ satisfaction with care in the outpatient clinic. Furthermore, the review showed that hope and positivity was a need and strategy for patients with cancer and was facilitated by health care professionals. Finally, it revealed that outpatient clinic visits framed and influenced communication and relationships. Conclusions: This review identified the significance of communication and the relationships between patients and health care professionals in the outpatient setting as it supports patients’ ability to cope with cancer. The review showed the need for health care professionals to pay attention to the relational aspects of communication in an outpatient clinic as encounters are often brief. Furthermore, the review helps to specify which elements of the communication are central in the patient-health care professional interaction from the patients' perspective. Finally, it shows a need for more research to investigate which type of interaction and intervention would be the most effective in supporting patients’ coping during chemotherapy in an outpatient clinic.

Keywords: ambulatory chemotherapy, communication, health care professional-patient relation, nurse-patient relation, outpatient care, systematic review

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1825 Dielectric Behavior of 2D Layered Insulator Hexagonal Boron Nitride

Authors: Nikhil Jain, Yang Xu, Bin Yu

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Hexagonal boron nitride (h-BN) has been used as a substrate and gate dielectric for graphene field effect transistors (GFETs). Using a graphene/h-BN/TiN (channel/dielectric/gate) stack, key material properties of h-BN were investigated i.e. dielectric strength and tunneling behavior. Work function difference between graphene and TiN results in spontaneous p-doping of graphene through a multi-layer h-BN flake. However, at high levels of current stress, n-doping of graphene is observed, possibly due to the charge transfer across the thin h-BN multi layer. Neither Direct Tunneling (DT) nor Fowler-Nordheim Tunneling (FNT) was observed in TiN/h-BN/Au hetero structures with h-BN showing two distinct volatile conduction states before breakdown. Hexagonal boron nitride emerges as a material of choice for gate dielectrics in GFETs because of robust dielectric properties and high tunneling barrier.

Keywords: graphene, transistors, conduction, hexagonal boron nitride, dielectric strength, tunneling

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1824 Gravity and Geodetic Control of Geodynamic Activity near Aswan Lake, Egypt

Authors: Anwar H. Radwan, Jan Mrlina, El-Sayed A. Issawy, Ali Rayan, Salah M. Mahmoud

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Geodynamic investigations in the Aswan Lake region were started after the M=5.5 earthquake in 1981, triggered by the lake water fluctuations. Besides establishing the seismological networks, also the geodetic observations focused on the Kalabsha and Sayal fault zones were started. It was found that the Kalabsha fault is an active dextral strike-slip with normal component indicating uplift on its southern side. However, the annual velocity rates in both components do not exceed 2 mm/y, and do not therefore represent extremely active faulting. We also launched gravity monitoring in 1997, and performed another two campaigns in 2000 and 2002. The observed non- tidal temporal gravity changes indicate rather the flood water infiltration into the porous Nubian sandstone, than tectonic stress effect. The station nearest to the lake exhibited about 60 μGal positive gravity change within the 1997-2002 period.

Keywords: gravity monitoring, surface movements, Lake Aswan, groundwater change

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1823 Phytochemical and Vitamin Composition of Wild Edible Plants Consumed in South West Ethiopia

Authors: Abebe Yimer, Sirawdink Fikereyesus Forsido, Getachew Addis, Abebe Ayelign

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Background: Oxidative stress has been an important health problem as itinduceschronic diseases such as cancer, cardiovascular, diabetics, and neurodegenerative disease. Plant source natural antioxidant has gained attention as synthetic antioxidant negatively impact human health. Wild edible plants arecheap source of dietary-medicine in mainly rural communityin south-west Ethiopia and elsewhere the country. Thus, the study aimed to determine total pheneol,flavoinoids, antioxidant, vitamin C, and beta-carotene content from wild edible plants Solanum nigrum L., Vigna membranacea A. Rich, Dioscorea praehensilis Benth., Trilepisium madagascariense D.C.andCleome gynandra L. Methods: Methanol was used to extract samples of oven-dried edible plants. Total phenolic compound (TPC) was determined using a Folin Ciocalteu method, whereas total flavonoid content (TFC) was determined using the Aluminium chloride colorimetric method. By using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) tests, antioxidant activities were evaluated in vitro. Additionally, beta-carotene was assessed using a spectrophotometric technique, whilst vitamin C was determined using a titration approach. Results: Total flavonoid contentranged from 0.85±0.03 to 11.25±0.01 mg CE/g in D. praehensilis Benth. tuber and C. gynandra L, respectively. Total phenolic compounds varied from 0.25±0.06 GAE/g in D. praehensilis Benth tuber to 35.73±2.52 GAE/g in S.nigrum L. leaves. In the DPPH test, the highest antioxidant value (87.65%) was obtained in the S.nigrum L. leaves, whereas the smallest amount of antioxidant (50.12%)was contained in D. praehensilis Benth tuber. Similarly in FRAP assay,D. praehensilis Benth tuber showed the least reducing potential(49.16± 2.13mM Fe2+/100 g)whilst the highest reducing potential was presented in the S.nigrum L. leaves(188.12±1.13 mM Fe2+/100 g). The beta-carotene content was found between 11.81±0.00 mg/100g in D. praehensilis Benth tubers to 34.49±0.95 mg/100g in V. membranacea A. Rich leaves. The concentration of vitamin C ranged from 10.00±0.61 in D. praehensilis Benth tubers to 45±1.80 mg/100g in V. membranacea A. Rich leaves. The results showed that high positive linear correlations between TPC and TFC of WEPs (r=0.828), as well as between FRAP and total phenolic contents (r = 0.943) and FRAP and vitamin C (r= 0.928). Conclusion: These findings showed the total phenolic and flavonoid contents of Solanum nigrum L. and Cleome gynandra L, respectively, are abundant. The outcome may be used as a natural supply of dietary antioxidants, which may be useful in preventing oxidative stress. The study's findings also showed that Vigna membranacea A. Rich leaves were cheap source of vitamin C and beta-carotene for people who consumed these wild green. Additional research on the in vivo antioxidant activity, toxicological analysis, and promotion of these wild food plants for agricultural production should be taken into consideration.

Keywords: antioxidant activity, beta-carotene, flavonoids, phenolic content, and vitamin c

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1822 The Use of Biofeedback to Increase Resilience and Mental Health of Supersonic Pilots

Authors: G. Kloudova, S. Kozlova, M. Stehlik

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Pilots are operating in a high-risk environment rich in potential stressors, which negatively affect aviation safety and the mental health of pilots. In the research conducted, the pilots were offered mental training biofeedback therapy. Biofeedback is an objective tool to measure physiological responses to stress. After only six sessions, all of the pilots tested showed significant differences between their initial condition and their condition after therapy. The biggest improvement was found in decreased heart rate (in 83.3% of tested pilots) and respiration rate (66.7%), which are the best indicators of anxiety states and panic attacks. To incorporate all of the variables, we correlated the measured physiological state of the pilots with their personality traits. Surprisingly, we found a high correlation with peripheral temperature and confidence (0.98) and with heart rate and aggressiveness (0.97). A retest made after a one-year interval showed that in majority of the subjects tested their acquired self-regulation ability had been internalized.

Keywords: aviation, biofeedback, mental workload, performance psychology

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1821 1 kW Power Factor Correction Soft Switching Boost Converter with an Active Snubber Cell

Authors: Yakup Sahin, Naim Suleyman Ting, Ismail Aksoy

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A 1 kW power factor correction boost converter with an active snubber cell is presented in this paper. In the converter, the main switch turns on under zero voltage transition (ZVT) and turns off under zero current transition (ZCT) without any additional voltage or current stress. The auxiliary switch turns on and off under zero current switching (ZCS). Besides, the main diode turns on under ZVS and turns off under ZCS. The output current and voltage are controlled by the PFC converter in wide line and load range. The simulation results of converter are obtained for 1 kW and 100 kHz. One of the most important feature of the given converter is that it has direct power transfer as well as excellent soft switching techniques. Also, the converter has 0.99 power factor with the sinusoidal input current shape.

Keywords: power factor correction, direct power transfer, zero-voltage transition, zero-current transition, soft switching

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1820 Exploring Cardiovascular and Behavioral Impacts of Aerobic Exercise: A ‎Moroccan Perspective

Authors: Ahmed Boujdad

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‎ Morocco, a North African nation known for its rich culture and diverse landscapes, is facing evolving challenges related to cardiovascular health and behavioral well-being. Against this backdrop, the paper aims to spotlight the insights emerging from Moroccan research into the impacts of aerobic exercise on cardiovascular physiology and psychological outcomes. Presentations will encompass a range of topics, including exercise-induced adaptations in heart function, blood pressure management, and vascular health specific to the Moroccan population. A notable focus of the paper will be the examination of how aerobic exercise intertwines with Moroccan behavioral patterns and sociocultural factors. The research will delve into the links between regular exercise and its potential to alleviate stress, anxiety, and depression in the Moroccan context. This exploration extends to the role of exercise in bolstering the cultural fabric of Moroccan society, enhancing community engagement, and promoting a sense of well-being.

Keywords: event-related potential‎, executive function, physical activity, kinesiology

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1819 Statistical Analysis of Cables in Long-Span Cable-Stayed Bridges

Authors: Ceshi Sun, Yueyu Zhao, Yaobing Zhao, Zhiqiang Wang, Jian Peng, Pengxin Guo

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With the rapid development of transportation, there are more than 100 cable-stayed bridges with main span larger than 300 m in China. In order to ascertain the statistical relationships among the design parameters of stay cables and their distribution characteristics, 1500 cables were selected from 25 practical long-span cable-stayed bridges. A new relationship between the first order frequency and the length of cable was found by conducting the curve fitting. Then, based on this relationship other interesting relationships were deduced. Several probability density functions (PDFs) were used to investigate the distributions of the parameters of first order frequency, stress level and the Irvine parameter. It was found that these parameters obey the Lognormal distribution, the Weibull distribution and the generalized Pareto distribution, respectively. Scatter diagrams of the three parameters were plotted and their 95% confidence intervals were also investigated.

Keywords: cable, cable-stayed bridge, long-span, statistical analysis

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1818 Magnetohydrodynamic (MHD) Effects on Micropolar-Newtonian Fluid Flow through a Composite Porous Channel

Authors: Satya Deo, Deepak Kumar Maurya

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The present study investigates the ow of a Newtonian fluid sandwiched between two rectangular porous channels filled with micropolar fluid in the presence of a uniform magnetic field applied in a direction perpendicular to that of the fluid motion. The governing equations of micropolar fluid are modified by Nowacki's approach. For respective porous channels, expressions for velocity vectors, microrotations, stresses (shear and couple) are obtained analytically. Continuity of velocities, continuities of micro rotations and continuity of stresses are used at the porous interfaces; conditions of no-slip and no spin are applied at the impervious boundaries of the composite channel. Numerical values of flow rate, wall shear stresses and couple stresses at the porous interfaces are calculated for different values of various parameters. Graphs of the ow rate and fluid velocity are plotted and their behaviors are discussed.

Keywords: couple stress, flow rate, Hartmann number, micropolar fluids

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1817 Effect of Welding Current on Mechanical Properties and Microstructure of Tungsten Inert Gas Welding of Type-304 Austenite Stainless Steel

Authors: Emmanuel Ogundimu, Esther Akinlabi, Mutiu Erinosho

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The aim of this paper is to study the effect of welding current on the microstructure and the mechanical properties. Material characterizations were conducted on a 6 mm thick plates of type-304 austenite stainless steel, welded by TIG welding process at two different welding currents of 150 A (Sample F3) and 170 A (Sample F4). The tensile strength and the elongation obtained from sample F4 weld were approximately 584 MPa and 19.3 %; which were higher than sample F3 weld. The average microhardness value of sample F4 weld was found to be 235.7 HV, while that of sample F3 weld was 233.4 HV respectively. Homogenous distribution of iron (Fe), chromium (Cr) and nickel (Ni) were observed at the welded joint of the two samples. The energy dispersive spectroscopy (EDS) analysis revealed that Fe, Cr, and Ni made up the composition formed in the weld zone. The optimum welding current of 170 A for TIG welding of type-304 austenite stainless steel can be recommended for high-tech industrial applications.

Keywords: microhardness, microstructure, tensile, MIG welding, process, tensile, shear stress TIG welding, TIG-MIG welding

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1816 Psychological Variables Predicting Academic Achievement in Argentinian Students: Scales Development and Recent Findings

Authors: Fernandez liporace, Mercedes Uriel Fabiana

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Academic achievement in high school and college students is currently a matter of concern. National and international assessments show high schoolers as low achievers, and local statistics indicate alarming dropout percentages in this educational level. Even so, 80% of those students intend attending higher education. On the other hand, applications to Public National Universities are free and non-selective by examination procedures. Though initial registrations are massive (307.894 students), only 50% of freshmen pass their first year classes, and 23% achieves a degree. Low performances use to be a common problem. Hence, freshmen adaptation, their adjustment, dropout and low academic achievement arise as topics of agenda. Besides, the hinge between high school and college must be examined in depth, in order to get an integrated and successful path from one educational stratum to the other. Psychology aims at developing two main research lines to analyse the situation. One regarding psychometric scales, designing and/or adapting tests, examining their technical properties and their theoretical validity (e.g., academic motivation, learning strategies, learning styles, coping, perceived social support, parenting styles and parental consistency, paradoxical personality as correlated to creative skills, psychopathological symptomatology). The second research line emphasizes relationships within the variables measured by the former scales, facing the formulation and testing of predictive models of academic achievement, establishing differences by sex, age, educational level (high school vs college), and career. Pursuing these goals, several studies were carried out in recent years, reporting findings and producing assessment technology useful to detect students academically at risk as well as good achievers. Multiple samples were analysed totalizing more than 3500 participants (2500 from college and 1000 from high school), including descriptive, correlational, group differences and explicative designs. A brief on the most relevant results is presented. Providing information to design specific interventions according to every learner’s features and his/her educational environment comes up as a mid-term accomplishment. Furthermore, that information might be helpful to adapt curricula by career, as well as for implementing special didactic strategies differentiated by sex and personal characteristics.

Keywords: academic achievement, higher education, high school, psychological assessment

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1815 Development of a New Method for T-Joint Specimens Testing under Shear Loading

Authors: Radek Doubrava, Roman Ruzek

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Nonstandard tests are necessary for analyses and verification of new developed structural and technological solutions with application of composite materials. One of the most critical primary structural parts of a typical aerospace structure is T-joint. This structural element is loaded mainly in shear, bending, peel and tension. The paper is focused on the shear loading simulations. The aim of the work is to obtain a representative uniform distribution of shear loads along T-joint during the mechanical testing is. A new design of T-joint test procedure, numerical simulation and optimization of representative boundary conditions are presented. The different conditions and inaccuracies both in simulations and experiments are discussed. The influence of different parameters on stress and strain distributions is demonstrated on T-joint made of CFRP (carbon fiber reinforced plastic). A special test rig designed by VZLU (Aerospace Research and Test Establishment) for T-shear test procedure is presented.

Keywords: T-joint, shear, composite, mechanical testing, finite element analysis, methodology

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1814 Reimagining Urban Food Security Through Informality Practices: The Case of Street Food Vending in Johannesburg, South Africa

Authors: Blessings Masuku

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This study positions itself within the nascent of street food vending that plays a crucial role in addressing urban household food security across the urban landscape of South Africa. The study aimed to understand how various forms of infrastructure systems (i.e., energy, water and sanitation, housing, and transport, among others) intersect with food and urban informality and how vendors and households’ choices and decisions made around food are influenced by infrastructure assemblages. This study noted that most of the literature studies on food security have mainly focused on the rural agricultural sector, with limited attention to urban food security, notably the role of informality practices in addressing urban food insecurity at the household level. This study pays close attention to how informal informality practices such as street food vending can be used as a catalyst to address urban poverty and household food security and steer local economies for sustainable livelihoods of the urban poor who live in the periphery of the city in Johannesburg. This study deconstructs the infrastructure needs of street food vendors, and the aim was to understand how such infrastructure needs intersect with food and policy that governs urban informality practices. The study argues that the decisions and choices of informality actors in the city of Johannesburg are chiefly determined by the assemblages of infrastructure, including regulatory frameworks that govern the informal sector in the city of Johannesburg. A qualitative approach that includes surveys (open-ended questions), archival research (i., e policy and other key document reviews), and key interviews mainly with city officials and informality actors. A thematic analysis was used to analyze the data collected. This study contributes to greater debates on urban studies and burgeoning literature on urban food security in many ways that include Firstly, the pivotal role that the informal food sector, notably street food vending, plays within the urban economy to address urban poverty and household food security, therefore questioning the conservative perspectives that view the informal sector as a hindrance to a ‘modern city’ and an annoyance to ‘modern’ urban spaces. Secondly, this study contributes to the livelihood and coping strategies of the urban poor who, despite harsh and restrictive regulatory frameworks, devise various agentive ways to generate incomes and address urban poverty and food insecurities.

Keywords: urban food security, street food vending, informal food sector, infrastructure systems, livelihood strategies, policy framework and governance

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1813 DC-to-DC Converters for Low-Voltage High-Power Renewable Energy Systems

Authors: Abdar Ali, Rizwan Ullah, Zahid Ullah

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This paper focuses on the study of DC-to-DC converters, which are suitable for low-voltage high-power applications. The output voltages generated by renewable energy sources such as photovoltaic arrays and fuel cell stacks are generally low and required to be increased to high voltage levels. Development of DC-to-DC converters, which provide high step-up voltage conversion ratios with high efficiencies and low voltage stresses is one of the main issues in the development of renewable energy systems. A procedure for three converters-conventional DC-to-DC converter, interleaved boost converter, and isolated flyback based converter, is illustrated for a given set of specifications. The selection among the converters for the given application is based on the voltage conversion ratio, efficiency, and voltage stresses.

Keywords: flyback converter, interleaved boost, photovoltaic array, fuel cell, switch stress, voltage conversion ratio, renewable energy

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1812 Chemical Functionalization of Graphene Oxide for Improving Mechanical and Thermal Properties of Polyurethane Composites

Authors: Qifei Jing, Vadim V. Silberschmidt, Lin Li, ZhiLi Dong

Abstract:

Graphene oxide (GO) was chemically functionalized to prepare polyurethane (PU) composites with improved mechanical and thermal properties. In order to achieve a well exfoliated and stable GO suspension in an organic solvent (dimethylformamide, DMF), 4, 4′- methylenebis(phenyl isocyanate) and polycaprolactone diol, which were the two monomers for synthesizing PU, were selectively used to functionalize GO. The obtained functionalized GO (FGO) could form homogeneous dispersions in DMF solvent and the PU matrix, as well as provide a good compatibility with the PU matrix. The most efficient improvement of mechanical properties was achieved when 0.4 wt% FGO was added into the PU matrix, showing increases in the tensile stress, elongation at break and toughness by 34.2%, 27.6% and 64.5%, respectively, compared with those of PU. Regarding the thermal stability, PU filled with 1 wt% FGO showed the largest extent of improvement with T2% and T50% (the temperatures at which 2% and 50% weight-loss happened) 16 °C and 21 °C higher than those of PU, respectively. The significant improvement in both mechanical properties and thermal stability of FGO/PU composites should be attributed to the homogeneous dispersion of FGO in the PU matrix and strong interfacial interaction between them.

Keywords: composite, dispersion, graphene oxide, polyurethane

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1811 Segmentation along the Strike-slip Fault System of the Chotts Belt, Southern Tunisia

Authors: Abdelkader Soumaya, Aymen Arfaoui, Noureddine Ben Ayed, Ali Kadri

Abstract:

The Chotts belt represents the southernmost folded structure in the Tunisian Atlas domain. It is dominated by inherited deep extensional E-W trending fault zones, which are reactivated as strike-slip faults during the Cenozoic compression. By examining the geological maps at different scales and based on the fieldwork data, we propose new structural interpretations for the geometries and fault kinematics in the Chotts chain. A set of ENE-WSW right-lateral en echelon folds, with curved shapes and steeply inclined southern limbs, is visible in the map view of this belt. These asymmetric tight anticlines are affected by E-W trending fault segments linked by local bends and stepovers. The revealed kinematic indicators along one of these E-W striated faults (Tafferna segment), such as breccias and gently inclined slickenlines (N094, 80N, 15°W pitch angles), show direct evidence of dextral strike-slip movement. The calculated stress tensors from corresponding faults slip data reveal an overall strike-slip tectonic regime with reverse component and NW-trending sub-horizontal σ1 axis ranking between N130 to N150. From west to east, we distinguished several types of structures along the segmented dextral fault system of the Chotts Range. The NE-SW striking fold-thrust belt (~25 km-long) between two continuously linked E-W fault segments (NW of Tozeur town) has been suggested as a local restraining bend. The central part of the Chotts chain is occupied by the ENE-striking Ksar Asker anticlines (Taferna, Torrich, and Sif Laham), which are truncated by a set of E-W strike-slip fault segments. Further east, the fault segments of Hachichina and Sif Laham connected across the NW-verging asymmetric fold-thrust system of Bir Oum Ali, which can be interpreted as a left-stepping contractional bend (~20 km-long). The oriental part of the Chotts belt corresponds to an array of subparallel E-W oriented fault segments (i.e., Beidha, Bouloufa, El Haidoudi-Zemlet El Beidha) with similar lengths (around 10 km). Each of these individual separated segments is associated with curved ENE-trending en echelon right-stepping anticlines. These folds are affected by a set of conjugate R and R′ shear-type faults indicating a dextral strike-lip motion. In addition, the relay zones between these E-W overstepping fault segments define local releasing stepovers dominated by NW-SE subsidiary faults. Finally, the Chotts chain provides well-exposed examples of strike-slip tectonics along E-W distributed fault segments. Each fault zone shows a typical strike-slip architecture, including parallel fault segments connecting via local stepovers or bends. Our new structural interpretations for this region reveal a great influence of the E-W deep fault segments on regional tectonic deformations and stress field during the Cenozoic shortening.

Keywords: chotts belt, tunisian atlas, strike-slip fault, stepovers, fault segments

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1810 Numerical Investigation of Wastewater ‎Rheological Characteristics on Flow Field ‎Inside a Sewage Network

Authors: Seyed-Mohammad-Kazem Emami, Behrang Saki, Majid Mohammadian

Abstract:

The wastewater flow field inside a sewage network including pipe and ‎manhole was investigated using a Computational Fluid Dynamics ‎‎(CFD) model. The numerical model is developed by incorporating a ‎rheological model to calculate the viscosity of wastewater fluid by ‎means of open source toolbox OpenFOAM. The rheological ‎properties of prepared wastewater fluid suspensions are first measured ‎using a BrookField LVDVII Pro+ viscometer with an enhanced UL ‎adapter and then correlated the suitable rheological viscosity model ‎values from the measured rheological properties. The results show the ‎significant effects of rheological characteristics of wastewater fluid on ‎the flow domain of sewer system. Results were compared and ‎discussed with the commonly used Newtonian model to evaluate the ‎differences for velocity profile, pressure and shear stress. ‎

Keywords: Non-Newtonian flows, Wastewater, Numerical simulation, Rheology, Sewage Network

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1809 Long-Term Psychosocial Issues Among COVID-19 Survivors in Kathmandu Valley

Authors: Nabin Prasad Joshi, Samiksha Neupane

Abstract:

Since its emergence in December 2019, Corona Virus disease has impacted several countries, affecting many people. The first cases were recorded in Wuhan, China, between December 2019 and January 2020. Italy is one of the affected countries in Europe. The relations between India and Nepal have reverted to the pre-pandemic period as both countries have open borders. The study focused on the overall psychosocial impact among covid-19 survivors in their life what are the changes they are facing after covid also how are their relations with friends and relatives after they have covid in different municipalities of Kathmandu valley, where people from different regions are living in rent and have their own houses. Support from friends and family during a pandemic can prevent it if it is strong enough. Nonetheless, there were risk factors for psychosocial damage, including a lack of or insufficient family and social support, psychiatric assistance, and inadequate insurance or compensation. Poorer mental health outcomes were inversely correlated with social rejection or isolation.

Keywords: stress, anxiety, depression, Kathmandu

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1808 High Temperature Creep Analysis for Lower Head of Reactor Pressure Vessel

Authors: Dongchuan Su, Hai Xie, Naibin Jiang

Abstract:

Under severe accident cases, the nuclear reactor core may meltdown inside the lower head of the reactor pressure vessel (RPV). Retaining the melt pool inside the RPV is an important strategy of severe accident management. During this process, the inner wall of the lower head will be heated to high temperature of a thousand centigrade, and the outer wall is immersed in a large amount of cooling water. The material of the lower head will have serious creep damage under the high temperature and the temperature difference, and this produces a great threat to the integrity of the RPV. In this paper, the ANSYS program is employed to build the finite element method (FEM) model of the lower head, the creep phenomena is simulated under the severe accident case, the time dependent strain and stress distribution is obtained, the creep damage of the lower head is investigated, the integrity of the RPV is evaluated and the theoretical basis is provided for the optimized design and safety assessment of the RPV.

Keywords: severe accident, lower head of RPV, creep, FEM

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1807 Rural Tourism in Indian Himalayan Region: A Scope for Sustainable Livelihood

Authors: Rommila Chandra, Harshika Choudhary

Abstract:

The present-day tourism sector is globally developing at a fast pace, searching for new ideas and new venues. In the Indian Himalayan Region (IHR), tourism has experienced a vast growth and continuous diversification over the last few years, thus becoming one of the fastest-growing economic sectors in India. With its majestic landscape, high peaks, rich floral and faunal diversity, and cultural history, the IHR has continuously attracted tourists and pilgrims from across the globe. The IHR has attracted a vast range of visitors who seek adventure sports, natural and spiritual solace, peace, cultural assets, food, and festivals, etc. Thus, the multi-functionality of the region has turned tourism into a key component of economic growth for the rural communities in the hills. For the local mountain people, it means valuable economic opportunity for income generation, and for the government and entrepreneurs, it brings profits. As the urban cities gain attention and investment in India, efforts have to be made to protect, safeguard, and strengthen the cultural, spiritual, and natural heritage of IHR for sustainable livelihood development. Furthermore, the socio-economic and environmental insecurities, along with geographical isolation, adds to the challenging survival in the tough terrains of IHR, creating a major threat of outmigration, land abandonment, and degradation. The question the paper intends to answer is: whether the rural community of IHR is aware of the new global trends in rural tourism and the extent of their willingness to adapt to the evolving tourism industry, which impacts the rural economy, including sustainable livelihood opportunity. The objective of the paper is to discuss the integrated nature of rural tourism, which widely depends upon natural resources, cultural heritage, agriculture/horticulture, infrastructural development, education, social awareness, and willingness of the locals. The sustainable management of all these different rural activities can lead to long-term livelihood development and social upliftment. It highlights some gap areas and recommends fewcommunity-based coping measures which the local people can adopt amidst the disorganized sector of rural tourism. Lastly, the main contribution is the exploratory research of the rural tourism vulnerability in the IHR, which would further help in studying the resilience of the tourism sector in the rural parts of a developing nation.

Keywords: community-based approach, sustainable livelihood development, Indian Himalayan region, rural tourism

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1806 Water Crisis or Crisis of Water Management: Assessing Water Governance in Iran

Authors: Sedigheh Kalantari

Abstract:

Like many countries in the arid and semi-arid belt, Iran experiences a natural limitation in the availability of water resources. However, rapid socioeconomic development has created a serious water crisis in a nation that was once one of the world’s pioneers in sustainable water management, due to the Persians’ contribution to hydraulic engineering inventions – the Qanat – throughout history. The exogenous issues like the changing climate, frequent droughts, and international sanctions are only crisis catalyzers, not the main cause of the water crisis; and a resilient water management system is expected to be capable of coping with these periodic external pressures. The current dramatic water security issues in Iran are rooted in managerial, political, and institutional challenges rather than engineering and technical issues, and the country is suffering from challenges in water governance. The country, instead of rigorous water conservation efforts, is still focused on supply-driven approach, technology and centralized methods, and structural solutions that aim to increase water supply; while the effectiveness of water governance and management has often left unused. To solve these issues, it is necessary to assess the present situation and its evolution over time. In this respect, establishing water governance assessment mechanisms will be a significant aspect of this paper. The research framework, however, is a conceptual framework to assess governance performance of Iran to critically diagnose problematic issues and areas, as well as proffer empirically based solutions and determine the best possible steps towards transformational processes. This concept aims to measure the adequacy of current solutions and strategies designed to ameliorate these problems and then develop and prescribe adequate futuristic solutions. Thus, the analytical framework developed in this paper seeks to provide insights on key factors influencing water governance in Iranian cities, institutional frameworks to manage water across scales and authorities, multi-level management gaps and policy responses, through an evidence-based approach and good practices to drive reform toward sustainability and water resource conservation. The findings of this paper show that the current structure of the water governance system in Iran, coupled with the lack of a comprehensive understanding of the root causes of the problem, leaves minimal hope for developing sustainable solutions to Iran’s increasing water crisis. In order to follow sustainable development approaches, Iran needs to replace symptom management with problem prevention.

Keywords: governance, Iran, sustainable development, water management, water resources

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1805 Assessing Adaptive Capacity to Climate Change and Agricultural Productivity of Farming Households of Makueni County in Kenya

Authors: Lilian Mbinya Muasa

Abstract:

Climate change is inevitable and a global challenge with long term implications to the sustainable development of many countries today. The negative impacts of climate change are creating far reaching social, economic and environmental problems threatening lives and livelihoods of millions of people in the world. Developing countries especially sub-Saharan countries are more vulnerable to climate change due to their weak ecosystem, low adaptive capacity and high dependency on rain fed agriculture. Countries in Sub-Saharan Africa are more vulnerable to climate change impacts due to their weak adaptive capacity and over-reliance on rain fed agriculture. In Kenya, 78% of the rural communities are poor farmers who heavily rely on rain fed agriculture thus are directly affected by climate change impacts.Currently, many parts of Kenya are experiencing successive droughts which are contributing to persistently unstable and declining agricultural productivity especially in semi arid eastern Kenya. As a result, thousands of rural communities repeatedly experience food insecurity which plunge them to an ever over-reliance on relief food from the government and Non-Governmental Organization In addition, they have adopted poverty coping strategies to diversify their income, for instance, deforestation to burn charcoal, sand harvesting and overgrazing which instead contribute to environmental degradation.This research was conducted in Makueni County which is classified as one of the most food insecure counties in Kenya and experiencing acute environmental degradation. The study aimed at analyzing the adaptive capacity to climate change across farming households of Makueni County in Kenya by, 1) analyzing adaptive capacity to climate change and agricultural productivity across farming households, 2) identifying factors that contribute to differences in adaptive capacity across farming households, and 3) understanding the relationship between climate change, agricultural productivity and adaptive capacity. Analytical Hierarchy Process (AHP) was applied to determine adaptive capacity and Total Factor Productivity (TFP) to determine Agricultural productivity per household. Increase in frequency of prolonged droughts and scanty rainfall. Preliminary findings indicate a magnanimous decline in agricultural production in the last 10 years in Makueni County. In addition, there is an over reliance of households on indigenous knowledge which is no longer reliable because of the unpredictability nature of climate change impacts. These findings on adaptive capacity across farming households provide the first step of developing and implementing action-oriented climate change policies in Makueni County and Kenya.

Keywords: adaptive capacity, agricultural productivity, climate change, vulnerability

Procedia PDF Downloads 324
1804 Effectiveness of Prehabilitation on Improving Emotional and Clinical Recovery of Patients Undergoing Open Heart Surgeries

Authors: Fatma Ahmed, Heba Mostafa, Bassem Ramdan, Azza El-Soussi

Abstract:

Background: World Health Organization stated that by 2020 cardiac disease will be the number one cause of death worldwide and estimates that 25 million people per year will suffer from heart disease. Cardiac surgery is considered an effective treatment for severe forms of cardiovascular diseases that cannot be treated by medical treatment or cardiac interventions. In spite of the benefits of cardiac surgery, it is considered a major stressful experience for patients who are candidate for surgery. Prehabilitation can decrease incidences of postoperative complications as it prepares patients for surgical stress through enhancing their defenses to meet the demands of surgery. When patients anticipate the postoperative sequence of events, they will prepare themselves to act certain behaviors, identify their roles and actively participate in their own recovery, therefore, anxiety levels are decreased and functional capacity is enhanced. Prehabilitation programs can comprise interventions that include physical exercise, psychological prehabilitation, nutritional optimization and risk factor modification. Physical exercises are associated with improvements in the functioning of the various physiological systems, reflected in increased functional capacity, improved cardiac and respiratory functions and make patients fit for surgical intervention. Prehabilitation programs should also prepare patients psychologically in order to cope with stress, anxiety and depression associated with postoperative pain, fatigue, limited ability to perform the usual activities of daily living through acting in a healthy manner. Notwithstanding the benefits of psychological preparations, there are limited studies which investigated the effect of psychological prehabilitation to confirm its effect on psychological, quality of life and physiological outcomes of patients who had undergone cardiac surgery. Aim of the study: The study aims to determine the effect of prehabilitation interventions on outcomes of patients undergoing cardiac surgeries. Methods: Quasi experimental study design was used to conduct this study. Sixty eligible and consenting patients were recruited and divided into two groups: control and intervention group (30 participants in each). One tool namely emotional, physiological, clinical, cognitive and functional capacity outcomes of prehabilitation intervention assessment tool was utilized to collect the data of this study. Results: Data analysis showed significant improvement in patients' emotional state, physiological and clinical outcomes (P < 0.000) with the use of prehabilitation interventions. Conclusions: Cardiac prehabilitation in the form of providing information about surgery, circulation exercise, deep breathing exercise, incentive spirometer training and nutritional education implemented daily by patients scheduled for elective open heart surgery one week before surgery have been shown to improve patients' emotional state, physiological and clinical outcomes.

Keywords: emotional recovery, clinical recovery, coronary artery bypass grafting patients, prehabilitation

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