Search results for: inner damage

Authors: Seyyed Abbas Mojtabavi, Mojtaba Fatzaneh Moghadam, Masoud Mahdavi

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Steel Metal Shear Wall is one of the most common and widely used energy dissipation systems in structures, which is used today as a damping system due to the increase in the construction of metal structures. In the present study, the shear wall of the steel plate with dimensions of 5×3 m and thickness of 0.024 m was modeled with 2 floors of total height from the base level with finite element method in Abaqus software. The loading is done as a concentrated load at the upper point of the shear wall on the second floor based on step type buckle. The mesh in the model is applied in two directions of length and width of the shear wall, equal to 0.02 and 0.033, respectively, and the mesh in the models is of sweep type. Finally, it was found that the steel plate shear wall with cavity (CSPSW) compared to the SPSW model, S (Mises), Smax (In-Plane Principal), Smax (In-Plane Principal-ABS), Smax (Min Principal) increased by 53%, 70%, 68% and 43%, respectively. The presence of cavities has led to an increase in the estimated stresses, but their presence has caused critical stresses and critical deformations created to be removed from the inner surface of the shear wall and transferred to the desired sections (regular cavities) which can be suggested as a solution in seismic design and improvement of the structure to transfer possible damage during the earthquake and storm to the desired and pre-designed location in the structure.

Keywords: steel plate shear wall, abacus software, finite element method, , boundary element, seismic structural improvement, von misses stress

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Authors: Ayesha Aihetasham, Najma Arshad, Sobia Khan

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Damage causes by subterranean termites are of major concern today. Termites majorly treated with pesticides resulted in several problems related to health and environment. For this reason, plant-derived natural products specifically essential oils have been evaluated in order to control termites. The aim of the present study was to investigate the antitermitic potential of six essential oils on Heterotermes indicola subterranean termite. No-choice bioassay was used to assess the termiticidal action of essential oils. Further, gut from each set of treated termite group was extracted and analyzed for reduction in number of protozoa and bacteria by protozoal count method using haemocytometer and viable bacterial plate count (dilution method) respectively. In no-choice bioassay it was found that Foeniculum vulgare oil causes high degree of mortality 90 % average mortality at 10 mg oil concentration (10mg/0.42g weight of filter paper). Least mortality appeared to be due to Citrus sinensis oil (43.33 % average mortality at 10 mg/0.42g). The highest activity verified to be of Foeniculum vulgare followed by Eruca sativa, Trigonella foenum-graecum, Peganum harmala, Syzygium cumini and Citrus sinensis. The essential oil which caused maximum reduction in number of protozoa was P. harmala followed by T. foenum-graecum and E. sativa. In case of bacterial count E. sativa oil indicated maximum decrease in bacterial number (6.4×10⁹ CFU/ml). It is concluded that F. vulgare, E. sativa and P. harmala essential oils are highly effective against H. indicola termite and its gut microflora.

Keywords: bacterial count, essential oils, Heterotermes indicola, protozoal count

Procedia PDF Downloads 246

Authors: P. Bublíkova, P. Halodova, H. K. Namburi, J. Stodolna, J. Duchon, O. Libera

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Neutron radiation-induced microstructural changes cause degradation of mechanical properties and the lifetime reduction of reactor internals during nuclear power plant operation. Investigating the effects of neutron irradiation on mechanical properties of the irradiated material (hardening, embrittlement) is challenging and time-consuming. Although the fast neutron spectrum has the major influence on microstructural properties, the thermal neutron effect is widely investigated owing to Irradiation-Assisted Stress Corrosion Cracking firstly observed in BWR stainless steels. In this study, 300-series austenitic stainless steels used as material for NPP's internals were examined after neutron irradiation at ~ 15 dpa. Although several nanoindentation experimental publications are available to determine the mechanical properties of ion irradiated materials, less is available on neutron irradiated materials at high dpa tested in hot-cells. In this work, we present particular methodology developed to determine the mechanical properties of neutron irradiated steels by nanoindentation technique. Furthermore, radiation-induced damage in the specimens was investigated by High Resolution - Transmission Electron Microscopy (HR-TEM) that showed the defect features, particularly Frank loops, cavity microstructure, radiation-induced precipitates and radiation-induced segregation. The results of nanoindentation measurements and associated nanoscale defect features showed the effect of irradiation-induced hardening. We also propose methodologies to optimized sample preparation for nanoindentation and microscotructural studies.

Keywords: nanoindentation, thermal neutrons, radiation hardening, transmission electron microscopy

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Authors: Lucy Ampaw-Asiedu, Terri R. Norton

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In the wake of recent disasters happening around the world such as earthquake in Italy (January, 2017); hurricanes in the United States (US) (September 2016 and September 2017); and compounding disasters in Haiti (September 2010 and September 2016); to our best knowledge, never has the world seen the need to work on preemptive rather than reactionary measures to salvage this situation than now. Tornadoes are natural hazards that mostly affect mid-western and central states in the US. Tornadoes, like all natural hazards such as hurricanes, earthquakes, floods and others, are very destructive and result in massive destruction to homes, cause billions of dollars in damage and claims many lives. Healthcare facilities in general are vulnerable to disasters, and therefore, the safety of patients, health workers and those who come in to seek shelter should be a priority. The focus of this study is to assess disaster management measures instituted by healthcare facilities. Thus, the sole aim of the study is to examine the vulnerabilities and the design of safe spaces in healthcare facilities in Central US. Objectives that guide the study are to primarily identify the impacts of tornadoes in hospitals and to assess the structural design or specifications of safe spaces. St. John’s Regional Medical Center, now Mercy Hospital in Joplin, is used as a case study. Preliminary results show that the lateral base shear of the proposed design to be 684.24 ton (1508.49kip) for the safe space. Findings from this work will be used to make recommendations about the design of safe spaces for health care facilities in Central US.

Keywords: disaster management, safe spaces, structural design, tornado, vulnerability

Procedia PDF Downloads 215

Authors: G. Sivaraj, K. M. Parammasivam, R. Veeramanikandan, S. Nithish

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Reduction of ground clearance or (ride height) is a vital factor in minimizing aerodynamic drag force and improving vehicle performance. But in India, minimization of ground clearance is limited because of the road conditions. Due to this problem, reduction of aerodynamic drag and performance are not fully improved. In this view, this paper deals with the development of self-retractable front spoilers which are most suitable for Indian road conditions. These retractable spoilers are fitted in the front portion of the car and in speed below 60 km/hr these spoilers are in retracted positions. But, when the car crosses a speed above 60 km/hr, using electronic circuit the spoilers are activated. Thus, using this technique aerodynamic performance can be improved at a speed above 60 km/hr. Also, when the car speed is reduced below the 60 km/hr mark, the front spoiler are retracted which makes it as a normal car. This is because, in Indian roads, speed breakers are installed to cut off speed at particular places. Thus, in these circumstances there are chances of damaging front spoilers. Since, when the driver sees the speed breaker, he will automatically apply break to prevent damage, at this time using electronic circuit the front spoiler is retracted. However, accidentally when the driver fails to apply brakes there are chances for the front spoilers to get a hit. But as the front spoilers are made of Kevlar composite, it can withstand high impact loads and using a spring mechanism the spoilers are retracted immediately. By using CFD analysis and low-speed wind tunnel testing drag coefficient of the 1:10 scaled car model with and without self-retractable spoilers are calculated and validated. Also, using wind tunnel, proper working of self-retractable at car speed below and above 60 km/hr are validated.

Keywords: aerodynamic drag, CFD analysis, kevlar composite, self-retractable spoilers, wind tunnel

Procedia PDF Downloads 342

Authors: S. Ziaran, M. Musil, M. Cekan, O. Chlebo

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The paper analyzes the response of buildings and industrially structures on seismic waves (low frequency mechanical vibration) generated by blasting operations. The principles of seismic analysis can be applied for different kinds of excitation such as: earthquakes, wind, explosions, random excitation from local transportation, periodic excitation from large rotating and/or machines with reciprocating motion, metal forming processes such as forging, shearing and stamping, chemical reactions, construction and earth moving work, and other strong deterministic and random energy sources caused by human activities. The article deals with the response of seismic, low frequency, mechanical vibrations generated by nearby blasting operations on a residential home. The goal was to determine the fundamental natural frequencies of the measured structure; therefore it is important to determine the resonant frequencies to design a suitable modal damping. The article also analyzes the package of seismic waves generated by blasting (Primary waves – P-waves and Secondary waves S-waves) and investigated the transfer regions. For the detection of seismic waves resulting from an explosion, the Fast Fourier Transform (FFT) and modal analysis, in the frequency domain, is used and the signal was acquired and analyzed also in the time domain. In the conclusions the measured results of seismic waves caused by blasting in a nearby quarry and its effect on a nearby structure (house) is analyzed. The response on the house, including the fundamental natural frequency and possible fatigue damage is also assessed.

Keywords: building structure, seismic waves, spectral analysis, structural response

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Authors: Ahmed ElAzab, Amira M. Idrees, Mahmoud A. Mahmoud, Hesham Hefny

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Social networking sites such as Twitter and Facebook attracts over 500 million users across the world, for those users, their social life, even their practical life, has become interrelated. Their interaction with social networking has affected their life forever. Accordingly, social networking sites have become among the main channels that are responsible for vast dissemination of different kinds of information during real time events. This popularity in Social networking has led to different problems including the possibility of exposing incorrect information to their users through fake accounts which results to the spread of malicious content during life events. This situation can result to a huge damage in the real world to the society in general including citizens, business entities, and others. In this paper, we present a classification method for detecting fake accounts on Twitter. The study determines the minimized set of the main factors that influence the detection of the fake accounts on Twitter, then the determined factors have been applied using different classification techniques, a comparison of the results for these techniques has been performed and the most accurate algorithm is selected according to the accuracy of the results. The study has been compared with different recent research in the same area, this comparison has proved the accuracy of the proposed study. We claim that this study can be continuously applied on Twitter social network to automatically detect the fake accounts, moreover, the study can be applied on different Social network sites such as Facebook with minor changes according to the nature of the social network which are discussed in this paper.

Keywords: fake accounts detection, classification algorithms, twitter accounts analysis, features based techniques

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Authors: Ahmad Ali Shahid, M Shakil Shaukat

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Agriculture is the backbone of economy of Pakistan and Cotton is the major agricultural export and supreme source of raw fiber for our textile industry. To combat against the developing resistance in the target insects and combating these challenges wholesomely, a novel combination of pyramided/stacked genes was conceptualized and later realized, through the means of biotechnology i.e., transformation of three genes namely, Cry1Ac, Cry2A, and EPSP synthase (glyphosate tolerant) genes in the locally cultivated cotton variety. The progenies of the transformed plants were successfully raised and screened under the tunnel conditions for two generations and the present study focused on the screening of plants which were confirmed for containing all of these three genes and their expressions. Initially, the screening was done through glyphosate spray assay and the plants which were healthy and showed no damage on leaves were selected after 07 days of spray. In the laboratory, the DNA of these plants were isolated and subjected to amplification of the three genes. Thus, seventeen out of twenty were confirmed positive for Cry1Ac gene and ten out of twenty were positive for Cry2A gene and all twenty were positive for presence of EPSP synthase gene. Then, the ten plant samples which were confirmed with presence of all three genes were subjected to expression analysis of these proteins through ELISA. The results showed that eight out of ten plants were actively expressing the three transgenes. Real-time PCR was also done to quantify the expression levels of the EPSP synthase gene. Finally, eight plants were confirmed for the presence and active expression of all three genes in T3 generation of the triple gene transformed cotton. These plants may be subjected to T4 generation to develop a new stable variety in due course of time.

Keywords: agriculture, cotton, transformation, cry genes, ELISA, PCR

Procedia PDF Downloads 394

Authors: Adel Ahmadi Hosseini, Fatemeh Tavanaei, Alessandro Navarra, Ferri Hassani

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Mining engineering, as a part of geoscience, must address modern concerns. Traditional mining methods incorporate drill and blast technologies, which are followed by different issues, including excessive noise, vibration, air pollution, and safety hazards. Over the past two decades, mining engineers have sought alternative solutions to move from drill and blast to continuous methods to prevent such issues and improve sustainability in mining. Among the suggested methods, microwave treatment has shown promising results by creating micro/macro cracks in the rock structure prior to the operations. This research utilizes an energy-based analysis methodology to evaluate the efficiency of the microwave treatment in improving mining operations. The data analysis shows that increasing the input microwave energy dosage intensifies the rock damage. However, this approach can decrease the energy efficiency of the method by more than 50% in some cases. In this study, rock samples were treated with three power levels (3 kW, 7 kW, and 12 kW) and two energy dosages (20 kWh/t and 50 kWh/t), resulting in six conditions. To evaluate the impact of microwave treatment on the geomechanical behavior of the rocks, Unconfined Compressive Strength (UCS) tests were conducted on the microwave-treated samples, yielding stress-strain curves. Using the stress-strain curves, the effect of the different powers and energy dosages of microwaves are discussed. This research shows the potential of using microwave treatment to lead the industry to more sustainable mining.

Keywords: microwave treatment, microwave energy dosage, sustainable mining, rock fragmentation

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Authors: Larry E. Udu, Joseph N. Edeh

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Unarguably, the land is an indispensable factor of production and has been instrumental to numerous conflicts between crop farmers and herders in Nigeria. The conflicts pose a grave challenge to life and property, food security and ultimately to sustainable socio-economic development of the nation. The paper examines the causes of the Fulani herders/farmers conflicts, particularly in the Middle Belt; numerity of occurrences and extent of damage and their socio-economic implications. Content Analytical Approach was adopted as methodology wherein data was extensively drawn from the secondary source. Findings reveal that major causes of the conflict are attributable to violation of tradition and laws, trespass and cultural factors. Consequently, the numerity of attacks and level of fatality coupled with displacement of farmers, destruction of private and public facilities impacted negatively on farmers output with their attendant socio-economic implications on sustainable livelihood of the people and the nation at large. For instance, Mercy Corps (a Global Humanitarian Organization) in its research, 2013-2016 asserts that a loss of $14billion within 3 years was incurred and if the conflict were resolved, the average affected household could see increase income by at least 64 percent and potentially 210 percent or higher and that states affected by the conflicts lost an average of 47 percent taxes/IGR. The paper therefore recommends strict adherence to grazing laws; platform for dialogue bothering on compromises where necessary and encouragement of cattle farmers to build ranches for their cattle according to international standards.

Keywords: conflict, farmers, herders, Nigeria, socio-economic implications

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Authors: Manoj Sarda, Abhishek Agarwal, Juhi Kaushik, Vatsal Sanjay, Arup Kumar Das

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Railways in India remain primary mode of transport having one of the largest networks in the world and catering to billions of transits yearly. Catastrophic economic damage and loss to life is encountered over the past few decades due to fire to locomotives. Study of fire dynamics and fire propagation plays an important role in evacuation planning and reducing losses. Simulation based study of propagation of fire and soot inside an air conditioned coach of Indian locomotive is done in this paper. Finite difference based solver, Fire Dynamic Simulator (FDS) version 6 has been used for analysis. A single air conditioned 3 tier coupe closed to ambient surroundings by glass windows having occupancy for 8 people is the basic unit of the domain. A system of three such coupes combined is taken to be fundamental unit for the entire study to resemble effect to an entire coach. Analysis of flame and soot contours and concentrations is done corresponding to variations in heat release rate per unit volume (HRRPUA) of fire source, variations in conditioned air velocity being circulated inside coupes by vents and an alternate fire initiation and propagation mechanism via ducts. Quantitative results of fractional area in top and front view of the three coupes under fire and smoke are obtained using MATLAB (IMT). Present simulations and its findings will be useful for organizations like Commission of Railway Safety and others in designing and implementing safety and evacuation measures.

Keywords: air conditioned coaches, fire propagation, flame contour, soot flow, train fire

Procedia PDF Downloads 284

Authors: Masoud Mahdavi, Mojtaba Farzaneh Moghadam

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The seismic forces caused by the waves created in the depths of the earth during the earthquake hit the structure and cause the building to vibrate. Creating large seismic forces will cause low-strength sections in the structure to suffer extensive surface damage. The use of new steel shear walls in steel structures has caused the strength of the building and its main members (columns) to increase due to the reduction and depreciation of seismic forces during earthquakes. In the present study, an attempt was made to evaluate a type of steel shear wall that has regular holes in the inner sheet by modeling the finite element model with Abacus software. The shear wall of the steel plate, measuring 6000 × 3000 mm (one floor) and 3 mm thickness, was modeled with four different pores with a cross-sectional area. The shear wall was dynamically subjected to a time history of 5 seconds by three accelerators, El Centro, Imperial Valley and Kobe. The results showed that increasing the distance between the geometric center of the hole and the geometric center of the inner plate in the steel shear wall (increasing the R_CS index) caused the total maximum acceleration to be transferred from the perimeter of the hole to horizontal and vertical beams. The results also show that there is no direct relationship between R_CS index and total acceleration in steel shear wall and R_CS index is separate from the peak ground acceleration value of earthquake.

Keywords: hollow steel plate shear wall, time history analysis, finite element method, abaqus software

Procedia PDF Downloads 102

Authors: Monika Skura

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People with physical disabilities, as with other people with differences in appearance or style of functioning come under negative social mechanisms. Therefore, it is worth asking what the relationship of the group is, who experience psychosocial effects because of their physical disability, towards people with intellectual disabilities, hearing impairments, visual impairments, mental illnesses, and their own physically disabled group. To analyse the perception of people with a physical disability, the study explores three areas: the acceptance or rejection of society’s stigmatization towards persons with disabilities; the importance of their own experience regarding their disability, in relation to another kind of disability; their level of acceptance to social interactions, in relation to various types of disabilities. The research sample consisted of 90 people with physical disabilities, who suffer from damage to the locomotor system. The data was collected using a questionnaire and the Adjective Check List by H. B. Gough and A. B. Heilbrun. This study utilized focus interviews to develop survey items for the questionnaire. The findings highlight that the response from those who were physically disabled agreed with the opinions of general society, not only with the issue of promoting integrated solutions and offering assistance but also having the same preferences and opinions about specific types of disability. However, their perception regarding their own group was noticeably different from that of general society. In the light of the study, for people with physical disabilities, just as for able-bodied people, it can be challenging to develop a meaningful relationship with people who have disabilities. All forms of disability suffer from negative attitudes and opinions that exist in society. The majority of those who were researched were focused primarily on their own problems, this inevitably hinders the integrity of the entire group, making it more difficult for it to find a cohesive voice, in which to promote their place within society.

Keywords: general society’s opinions about disability, people with different kinds of disability, perception, physical disability

Procedia PDF Downloads 250

Authors: Sikander Nawaz Khan

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Natural disasters like flood, earthquake, cyclone, volcanic eruption and others are causing immense losses to the property and lives every year. Current status and actual loss information of natural hazards can be determined and also prediction for next probable disasters can be made using different remote sensing and mapping technologies. Global Positioning System (GPS) calculates the exact position of damage. It can also communicate with wireless sensor nodes embedded in potentially dangerous places. GPS provide precise and accurate locations and other related information like speed, track, direction and distance of target object to emergency responders. Remote Sensing facilitates to map damages without having physical contact with target area. Now with the addition of more remote sensing satellites and other advancements, early warning system is used very efficiently. Remote sensing is being used both at local and global scale. High Resolution Satellite Imagery (HRSI), airborne remote sensing and space-borne remote sensing is playing vital role in disaster management. Early on Geographic Information System (GIS) was used to collect, arrange, and map the spatial information but now it has capability to analyze spatial data. This analytical ability of GIS is the main cause of its adaption by different emergency services providers like police and ambulance service. Full potential of these so called 3S technologies cannot be used in alone. Integration of GPS and other remote sensing techniques with GIS has pointed new horizons in modeling of earth science activities. Many remote sensing cases including Asian Ocean Tsunami in 2004, Mount Mangart landslides and Pakistan-India earthquake in 2005 are described in this paper.

Keywords: disaster mitigation, GIS, GPS, remote sensing

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Authors: Md Imtiaz, Sanchita Dei, Shubham Damke

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In recent years, there has been a rapidly accelerating shift from traditional surface processing operations to subsea processing operation. This shift has been driven by a number of factors including the depletion of shallow fields around the world, technological advances in subsea processing equipment, the need for production from marginal fields, and lower initial upfront investment costs compared to traditional production facilities. Moving production facilities to the seafloor offers a number of advantage, including a reduction in field development costs, increased production rates from subsea wells, reduction in the need for chemical injection, minimization of risks to worker ,reduction in spills due to hurricane damage, and increased in oil production by enabling production from marginal fields. Subsea processing consists of a range of technologies for separation, pumping, compression that enables production from offshore well without the need for surface facilities. At present, there are two primary technologies being used for subsea processing: subsea multiphase pumping and subsea separation. Multiphase pumping is the most basic subsea processing technology. Multiphase pumping involves the use of boosting system to transport the multiphase mixture through pipelines to floating production vessels. The separation system is combined with single phase pumps or water would be removed and either pumped to the surface, re-injected, or discharged to the sea. Subsea processing can allow for an entire topside facility to be decommissioned and the processed fluids to be tied back to a new, more distant, host. This type of application reduces costs and increased both overall facility and integrity and recoverable reserve. In future, full subsea processing could be possible, thereby eliminating the need for surface facilities.

Keywords: FPSO, marginal field, Subsea processing, SWAG

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Authors: Venkataraman Sankaranarayanan, Sougata Ray

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While extant research has examined many aspects of differential corporate environmental outcomes and behavior, a holistic and integrated view of heterogeneity in corporate environment sustainability (CES) practices remains a puzzle to be fully unraveled – its extent and nature, its relationship to macro or micro level influences, or strategic orientations. Such a perspective would be meaningful for the field given notable strides in CES practices and the corporate social responsibility agenda over the last two decades, in the backdrop of altered global socio-political sensitivities and technological advances. To partly address this gap, this exploratory research adopted a content analysis approach to code patterns in the sustainability disclosures of the 160 largest global firms spread over 8 years. The sample of firms spanned seven industries, nine countries and three continents thereby presenting data rich and diverse enough in several dimensions to be representative of global heterogeneity in CES practices. Through a factor analysis of the coded data, four strategic CES orientations were extracted through the analysis, that effectively straddles most of the variation observed in current CES practices – one that seeks to reduce environmental damage on account of the firm’s operations, another that prioritizes minimalism, a third that focuses on broader ecological status quo, and a final one that champions the ‘business of green’, extending the CES agenda beyond the firm’s boundaries. These environment sustainability strategy orientations are further examined to elicit prominent patterns and explore plausible antecedents.

Keywords: corporate social responsibility, corporate sustainability, environmental management, heterogeneity, strategic orientation

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Authors: Fitri Ayu, Nadia, Tanti, Putri, Fatkhan, Pasid Harlisa, Suparmi

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Acne is a skin abnormal conditions experienced by many teens, this is caused by various factors such as the climate is hot, humid and excessive sun exposure can aggravate acne because it will lead to excess oil production. Flavonoids form complex compounds against extracellular proteins that disrupt the integrity of bacterial cell membrane in a way denature bacterial cell proteins and bacterial cell membrane damage. This study aimed to test the antibacterial activity of corn silk extract with a concentration of 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % and 100 % in vitro by measuring the inhibition of the growth of bacteria Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermis then compared with the standard antibiotic clindamycin. Extracts tested by Disk Diffusion Method, in which the blank disc soaked with their respective corn silk extract concentration for 15-30 minutes and then the medium of bacteria that have been planted with Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermis in the given disk that already contains extracts with various concentration. Incubated for 24 hours and then measured the growth inhibition zone Propionibacterium acne, Staphylococcus aureus and Staphylococcus epidermidis. Corn silk contains flavonoids, is shown by the test of flavonoids in corn silk extract by using a tube heating and without heating. Flavonoid in corn silk potentially as anti acne by inhibiting the growth of bacteria that cause acne. Corn silk extract concentration which has the highest antibacterial activity is then performed in a cream formulation and evaluation test of physical and chemical properties of the resulting cream preparation.

Keywords: antibacterial, flavonoid, corn silk, acne

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Authors: Hyo-Min Kim, Seokjin Ham, Mi-Joung Yoo, Minseon Kim, Tae-Young Roh

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The gastrointestinal (GI) tract of most animals, including murine, is highly compartmentalized epithelia which also provide distinct different functions of its own tissue. Nevertheless, these epithelia share certain characteristics that enhance immune responses to infections and maintain the barrier function of the intestine. GI tract epithelia also undergo regeneration not only in homeostatic conditions but also in a response to the damage. A full turnover of the murine gastrointestinal epithelium occurs every 4-5 day, a process that is regulated and maintained by a minor population of Lgr5+ adult stem cell that commonly conserved in the bottom of crypts through GI tract. Maintenance of the stem cell is somehow regulated by epigenetic factors according to recent studies. Chromatin vacancy, remodelers, histone variants and histone modifiers could affect adult stem cell fate. In this study, Lgr5-EGFP reporter mouse was used to take advantage of exploring the epigenetic dynamics among Lgr5 positive mutual stem cell in GI tract. Cells were isolated by fluorescence-activated cell sorting (FACS), gene expression levels, chromatin accessibility changes and histone modifications were analyzed. Some notable chromatin structural related epigenetic variants were detected. To identify the overall cell-cell interaction inside the stem cell niche, an extensive genome-wide analysis should be also followed. According to the results, nevertheless, we expected a broader understanding of cellular niche maintaining stem cells and epigenetic barriers through conserved stem cell in GI tract. We expect that our study could provide more evidence of adult stem cell plasticity and more chances to understand each stem cell that takes parts in certain organs.

Keywords: adult stem cell, epigenetics, LGR5 stem cell, gastrointestinal tract

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Authors: Ahlem Nefzi, Rania Aydi Ben Abdallah, Hayfa Jabnoun-Khiareddine, Nawaim Ammar, Sined Medimagh-Saidana, Mejda Daami-Remadi

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In the present study, leaf, stem, and fruit aqueous extracts of native wild Solanum linnaeanum L. were screened for their ability to suppress Fusarium Crown and Root Rot disease and to enhance tomato (Solanum lycopersicum L.) growth under greenhouse conditions. Leaf extract used at 30% w/v was the most effective in reducing leaf and root damage index by 92.3% and the extent of vascular discoloration by 97.56% compared to Fusarium oxyxporum f. sp radicis lycopersici -inoculated and untreated control. A significant promotion of growth parameters (root length, shoot height, root and shoot biomass and stem diameter) was recorded on tomato cv. Rio Grande seedlings by 40.3-94.1% as compared to FORL inoculated control and by 9.6-88.8% over pathogen-free control. All S. linnaeanum aqueous extracts tested significantly stimulated the germination by 10.2 to 80.1% relative to the untreated control. FORL mycelial growth, assessed using the poisoned food technique, varied depending on plant organs, extracts, and concentrations used. Butanolic extracts were the most active, leading to 60.81% decrease in FORL mycelial growth. HPLC analysis of butanolic extract revealed the presence of thirteen phenolic compounds. Thus, S. linnaeanum can be explored as a potential natural source of antifungal and biofertilizing compounds.

Keywords: antifungal activity, HPLC-MS analysis, Fusarium oxysporum f. sp. radicis-lycopersici, tomato growth

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Authors: Won Young Choi, Kwan Kyu Park

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Recently, the road depression happening in the urban area is different from the cause of the sink hole and the generation mechanism occurring in the limestone area. The main cause of sinkholes occurring in the city center is the loss of soil due to the damage of old underground buried materials and groundwater discharge due to large underground excavation works. The method of detecting the sinkhole in the urban area is mostly using the Ground Penetration Radar (GPR). However, it is challenging to implement compact system and detecting watery state since it is based on electromagnetic waves. Although many ultrasonic underground detection studies have been conducted, near-ground detection (several tens of cm to several meters) has been developed for bulk systems using geophones as a receiver. The goal of this work is to fabricate a miniaturized sinkhole detecting system based on low-cost ultrasonic transducers of 40 kHz resonant frequency with high transmission pressure and receiving sensitivity. Motived by biomedical ultrasonic imaging methods, we detect air layers below the ground such as asphalt through the pulse-echo method. To improve image quality using multi-channel, linear array system is implemented, and image is acquired by classical synthetic aperture imaging method. We present the successful feasibility test of multi-channel sinkhole detector based on ultrasonic transducer. In this work, we presented and analyzed image results which are imaged by single channel pulse-echo imaging, synthetic aperture imaging.

Keywords: road depression, sinkhole, synthetic aperture imaging, ultrasonic transducer

Procedia PDF Downloads 144

Authors: Mostafa Mabrouk, Basma E. Abdel-Ghany, Mona Moaness, Bothaina M. Abdel-Hady, Hanan H. Beherei

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Tissue engineering became a promising field for bone repair and regenerative medicine in which cultured cells, scaffolds and osteogenic inductive signals are used to regenerate tissues. The annual cost of treating bone defects in Egypt has been estimated to be many billions, while enormous costs are spent on imported bone grafts for bone injuries, tumors, and other pathologies associated with defective fracture healing. The current study is aimed at developing a more strategic approach in order to speed-up recovery after bone damage. This will reduce the risk of fatal surgical complications and improve the quality of life of people affected with such fractures. 3D scaffolds loaded with cheap nano-particles that possess an osteogenic effect were prepared by nano-electrospinning. The Microstructure and morphology characterizations of the 3D scaffolds were monitored using scanning electron microscopy (SEM). The physicochemical characterization was investigated using X-ray diffractometry (XRD) and infrared spectroscopy (IR). The Physicomechanical properties of the 3D scaffold were determined by a universal testing machine. The in vitro bioactivity of the 3D scaffold was assessed in simulated body fluid (SBF). The bone-bonding ability of novel 3D scaffolds was also evaluated. The obtained nanofibrous scaffolds demonstrated promising microstructure, physicochemical and physicomechanical features appropriate for enhanced bone regeneration. Therefore, the utilized nanomaterials loaded with the drug are greatly recommended as cheap alternatives to growth factors.

Keywords: bone regeneration, cheap scaffolds, nanomaterials, active molecules

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Authors: A. Jourani, C. Trevisiol, S. Bouvier

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The aim of this work is to study the coupled effect of microstructure and surface roughness on friction coefficient, wear resistance and wear mechanisms. Friction tests on 35NCD16 steel are performed under different normal loads (50-110 N) on a pin-on-plane configuration at cyclic sliding with abrasive silicon carbide grains ranging from 35 µm to 200 µm. To vary hardness and microstructure, the specimens are subjected to water quenching and tempering at various temperatures from 200°C to 600°C. The evolution of microstructures and wear mechanisms of worn surfaces are analyzed using scanning electron microscopy (SEM). For a given microstructure and hardness, the friction coefficient decreases with increasing of normal load and decreasing of the abrasive particle size. The wear rate increase with increasing of normal load and abrasive particle size. The results also reveal that there is a critical hardness Hcᵣᵢₜᵢcₐₗ around 430 Hv which maximizes the friction coefficient and wear rate. This corresponds to a microstructure transition from martensite laths to carbides and equiaxed grains, for a tempering around 400°C. Above Hcᵣᵢₜᵢcₐₗ the friction coefficient and the amount of material loss decrease with an increase of hardness and martensite volume fraction. This study also shows that the debris size and the space between the abrasive particles decrease with a reduction in the particle size. The coarsest abrasive grains lost their cutting edges, accompanied by particle damage and empty space due to the particle detachment from the resin matrix. The compact packing nature of finer abrasive papers implicates lower particle detachment and facilitates the clogging and the transition from abrasive to adhesive wear.

Keywords: martensite, microstructure, friction, wear, surface roughness

Procedia PDF Downloads 158

Authors: Rebeca V. Tholen, Elaine Bundy

Abstract:

Background: Liver transplantation (LT) is considered the only curative treatment for end-stage liver disease Background: Liver transplantation (LT) is considered the only curative treatment for end-stage liver disease (ESLD). The effects of alcoholism can cause irreversible liver damage, cirrhosis and subsequent liver failure. Alcohol relapse after transplant occurs in 20-50% of patients and increases the risk for recurrent cirrhosis, organ rejection, and graft failure. Alcohol relapse after transplant has been identified as a problem among liver transplant recipients at a large urban academic transplant center in the United States. Transplantation will reverse the complications of ESLD, but it does not treat underlying alcoholism or reduce the risk of relapse after transplant. The purpose of this quality improvement project is to implement and evaluate the effectiveness of a High-Risk Alcoholism Relapse (HRAR) Scale to screen and identify patients at high-risk for alcohol relapse after receiving an LT. Methods: The HRAR Scale is a predictive tool designed to determine the severity of alcoholism and risk of relapse after transplant. The scale consists of three variables identified as having the highest predictive power for early relapse including, daily number of drinks, history of previous inpatient treatment for alcoholism, and the number of years of heavy drinking. All adult liver transplant recipients at a large urban transplant center were screened with the HRAR Scale prior to hospital discharge. A zero to two ordinal score is ranked for each variable, and the total score ranges from zero to six. High-risk scores are between three to six. Results: Descriptive statistics revealed 25 patients were newly transplanted and discharged from the hospital during an 8-week period. 40% of patients (n=10) were identified as being high-risk for relapse and 60% low-risk (n=15). The daily number of drinks were determined by alcohol content (1 drink = 15g of ethanol) and number of drinks per day. 60% of patients reported drinking 9-17 drinks per day, and 40% reported ≤ 9 drinks. 50% of high-risk patients reported drinking ≥ 25 years, 40% for 11-25 years, and 10% ≤ 11 years. For number of inpatient treatments for alcoholism, 50% received inpatient treatment one time, 20% ≥ 1, and 30% reported never receiving inpatient treatment. Findings reveal the importance and value of a validated screening tool as a more efficient method than other screening methods alone. Integration of a structured clinical tool will help guide the drinking history portion of the psychosocial assessment. Targeted interventions can be implemented for all high-risk patients. Conclusions: Our findings validate the effectiveness of utilizing the HRAR scale to screen and identify patients who are a high-risk for alcohol relapse post-LT. Recommendations to help maintain post-transplant sobriety include starting a transplant support group within the organization for all high-risk patients. (ESLD). The effects of alcoholism can cause irreversible liver damage, cirrhosis and subsequent liver failure. Alcohol relapse after transplant occurs in 20-50% of patients, and increases the risk for recurrent cirrhosis, organ rejection, and graft failure. Alcohol relapse after transplant has been identified as a problem among liver transplant recipients at a large urban academic transplant center in the United States. Transplantation will reverse the complications of ESLD, but it does not treat underlying alcoholism or reduce the risk of relapse after transplant. The purpose of this quality improvement project is to implement and evaluate the effectiveness of a High-Risk Alcoholism Relapse (HRAR) Scale to screen and identify patients at high-risk for alcohol relapse after receiving a LT. Methods: The HRAR Scale is a predictive tool designed to determine severity of alcoholism and risk of relapse after transplant. The scale consists of three variables identified as having the highest predictive power for early relapse including, daily number of drinks, history of previous inpatient treatment for alcoholism, and the number of years of heavy drinking. All adult liver transplant recipients at a large urban transplant center were screened with the HRAR Scale prior to hospital discharge. A zero to two ordinal score is ranked for each variable, and the total score ranges from zero to six. High-risk scores are between three to six. Results: Descriptive statistics revealed 25 patients were newly transplanted and discharged from the hospital during an 8-week period. 40% of patients (n=10) were identified as being high-risk for relapse and 60% low-risk (n=15). The daily number of drinks were determined by alcohol content (1 drink = 15g of ethanol) and number of drinks per day. 60% of patients reported drinking 9-17 drinks per day, and 40% reported ≤ 9 drinks. 50% of high-risk patients reported drinking ≥ 25 years, 40% for 11-25 years, and 10% ≤ 11 years. For number of inpatient treatments for alcoholism, 50% received inpatient treatment one time, 20% ≥ 1, and 30% reported never receiving inpatient treatment. Findings reveal the importance and value of a validated screening tool as a more efficient method than other screening methods alone. Integration of a structured clinical tool will help guide the drinking history portion of the psychosocial assessment. Targeted interventions can be implemented for all high-risk patients. Conclusions: Our findings validate the effectiveness of utilizing the HRAR scale to screen and identify patients who are a high-risk for alcohol relapse post-LT. Recommendations to help maintain post-transplant sobriety include starting a transplant support group within the organization for all high-risk patients.

Keywords: alcoholism, liver transplant, quality improvement, substance abuse

Procedia PDF Downloads 116

Authors: Milad Abbasi

Abstract:

Carbon fiber-reinforced polymer (CFRP) composite structures are increasingly being utilized in the automotive industry due to their lightweight and specific energy absorption capabilities. Although it is impossible to predict composite mechanical properties directly using theoretical methods, various research has been conducted so far in the literature for accurate simulation of CFRP structures' energy-absorbing behavior. In this research, axial compression experiments were carried out on hand lay-up unidirectional CFRP composite tubes. The fabrication method allowed the authors to extract the material properties of the CFRPs using ASTM D3039, D3410, and D3518 standards. A neural network machine learning algorithm was then utilized to build a robust prediction model to forecast the axial compressive properties of CFRP tubes while reducing high-cost experimental efforts. The predicted results have been compared with the experimental outcomes in terms of load-carrying capacity and energy absorption capability. The results showed high accuracy and precision in the prediction of the energy-absorption capacity of the CFRP tubes. This research also demonstrates the effectiveness and challenges of machine learning techniques in the robust simulation of composites' energy-absorption behavior. Interestingly, the proposed method considerably condensed numerical and experimental efforts in the simulation and calibration of CFRP composite tubes subjected to compressive loading.

Keywords: CFRP composite tubes, energy absorption, crushing behavior, machine learning, neural network

Procedia PDF Downloads 153

Authors: Milad Gholizadeh

Abstract:

Asthma and chronic obstructive pulmonary disease (COPD) are very shared inflammatory diseases of the airlines. They togethercause airway tapering and are cumulative in occurrence throughout the world, imposing huge burdens on health care. It is currently recognized that some asthmatic inflammation is neutrophilic, controlled by the TH17 subset of helper T cells, and that some eosinophilic inflammation is controlled by type 2 innate lymphoid cells (ILC2 cells) temporary together with basophils. Patients who have plain asthma or are asthmatic patients who smoke with topographies of COPD-induced inflammation and might advantage from treatments targeting neutrophils, countingmacrolides, CXCR2 antagonists, phosphodiesterase 4 inhibitors, p38 mitogen-activating protein kinase inhibitors, and antibodies in contradiction of IL-1 and IL-17.Viral and bacterial infections, not only reason acute exacerbations of COPD, but also intensify and continue chronic inflammation in steady COPD through pathogen-associated molecular patterns. Present treatment plans are absorbed on titration of inhaled therapies such as long-acting bronchodilators, with cumulative interest in the usage of beleaguered biologic therapies meant at the underlying inflammatory devices. Educationssuggest that the mucosal IgA reply is abridged in COPD, and a lacking conveyance of IgA across the bronchial epithelium in COPD has been recognized, perhaps involving neutrophil proteinases, which may damage the Ig receptor mediating this transepithelialdirection-finding. Future instructions for investigation will emphasis elucidating the diverse inflammatory signatures foremost to asthma and chronic obstrucive, the development of reliable analytic standards and biomarkers of illness, and refining the clinical organization with an eye toward targeted therapies.

Keywords: imminology, asthma, COPD, CXCR2 antagonists

Procedia PDF Downloads 162

Authors: Salma Baig, Bakrudeen Ali Ahmad, Ainnul Hamidah Syahadah Azizan, Hapipah Mohd Ali, Elham Rouhollahi, Mahmood Ameen Abdulla

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Free radical damage induced by reactive oxygen species (ROS) contributes to etiology of many chronic diseases, cancer being one of them. Recent studies have been successful in ROS targeted therapies via antioxidants using mouse models in cancer therapeutics. The present study was designed to scrutinize anticancer activity, antioxidant activity of 5 different extracts of Thymus serpyllum in MDA-MB-231, MCF-7, HepG2, HCT-116, PC3, and A549. Identification of the phytochemicals present in the most active extract of Thymus serpyllum was conducted using gas chromatography coupled with mass spectrophotometry and antioxidant activity was measured by using DPPH radical scavenging and FRAP assay. Anticancer impact of the extract in terms of IC50 was evaluated using MTT cell viability assay. Results revealed that the hexane extract showed the best anticancer activity in HepG2 (Liver Carcinoma Cell Line) with an IC50 value of 23 ± 0.14 µg/ml followed by 25 µg/ml in HCT-116 (Colon Cancer Cell Line), 30 µm/ml in MCF-7 (Breast Cancer Cell Line), 35 µg/ml in MDA-MB-231 (Breast Cancer Cell Line), 57 µg/ml in PC3 (Prostate Cancer Cell Line) and 60 µg/ml in A549 (Lung Carcinoma Cell Line). GC-MS profile of the hexane extract showed the presence of 31 compounds with carvacrol, thymol and thymoquione being the major compounds. Phenolics such as Vitamin E, terpinen-4-ol, borneol and phytol were also identified. Hence, here we present the first report on cytotoxicity of hexane extract of Thymus serpyllum extract in HepG2 cell line with a robust anticancer activity with an IC50 of 23 ± 0.14 µg/ml.

Keywords: Thymus serpyllum L., hexane extract, GC-MS profile, antioxidant activity, anticancer activity, HepG2 cell line

Procedia PDF Downloads 517

Authors: Seyed Saeid Tabaee, Omid Bahar

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Nowadays, using energy dissipation devices has been commonly used in structures. A high rate of energy absorption during earthquakes is the benefit of using such devices, which results in damage reduction of structural elements specifically columns. The hysteretic damping capacity of energy dissipation devices is the key point that it may adversely complicate analysis and design of such structures. This effect may be generally represented by equivalent viscous damping. The equivalent viscous damping may be obtained from the expected hysteretic behavior under the design or maximum considered displacement of a structure. In this paper, the hysteretic damping coefficient of a steel moment resisting frame (MRF), which its performance is enhanced by a buckling restrained brace (BRB) system has been evaluated. Having the foresight of damping fraction between BRB and MRF is inevitable for seismic design procedures like Direct Displacement-Based Design (DDBD) method. This paper presents an approach to calculate the damping fraction for such systems by carrying out the dynamic nonlinear time history analysis (NTHA) under harmonic loading, which is tuned to the natural frequency of the system. Two steel moment frame structures, one equipped with BRB, and the other without BRB are simultaneously studied. The extensive analysis shows that proportion of each system damping fraction may be calculated by its shear story portion. In this way, the contribution of each BRB in the floors and their general contribution in the structural performance may be clearly recognized, in advance.

Keywords: buckling restrained brace, direct displacement based design, dual systems, hysteretic damping, moment resisting frames

Procedia PDF Downloads 434

Authors: Kh. Dehkordi, R. Sharifi Gholam, S. Arshadi

Abstract:

Objective: Oxidative stress is produced under diabetic conditions and possibly causes various forms of tissue damage inpatients with diabetes. Antioxidants defend against the harmful effect of free radicals, which are associated with heart disease, cancer, arthritis, aging and many other diseases1). Antioxidants are very stable molecules capable of neutralizing free radicals by donating an electron to them.The aim of this study was to examine the effect of swimming training, fenugreek seed extract and glibenclamide on plasma glucose and cardiac antioxidants activity in diabetic rats. Design: For this purpose, fifty male wistar rats were divided into five groups, two groups of control rats (diabetic control [DC] and healthy control [HC]), one group of endurance swimming training (EST), one group of fenugreek seed extract highdose (F1, 1.74 g/kg b.w), one group of fenugreek seed extract middle dose (F2, 0.87 g/kg b.w), one group of glibenclamide (G, 0.5 mg/kg b.w). Materials and Methods: Diabetes induced by streptozotocine (STZ), data was analyzed using the one-way ANOVA followed by a Tukey test. Significance level was 0.05. Results: All of the groups' exception of HC showed significant decrease in body weight (P < 0.05), but the diabetic control and swimming training group exhibited a more decrease. All of the groups have shown a significant decrease in plasma glucose than DC group (P < 0.05) but this reduction was more in G group than DC no HC group. S, G and HC groups have shown significant increase in cardiac antioxidant than DC group (P < 0.05) but there wasn't significant difference in other groups (P > 0.05). Conclusion: The present results indicate that regular swimming training lead to decrease in plasma glucose and enhanced cardiac antioxidants in diabetic rats.

Keywords: swimming, glucose, cardiac, antioxidants

Procedia PDF Downloads 303

Authors: Muhammad Faisal, Zai-Jin You, Muhammad Naeem

Abstract:

Concerns about the environment, public health, and the economy are raised by the fact that the world produces around 6 trillion cigarettes annually. Arguably the most pervasive forms of environmental litter, this dangerous trash must be eliminated. The researchers wanted to get an idea of how much pollution is seeping out of cigarette butts in metropolitan areas by studying their distribution and concentration. In order to accomplish this goal, the cigarette butt pollution indicator was applied in 29 different areas. The locations were monitored monthly for a full calendar year. The conditions for conducting the investigation of the venues were the same on both weekends and during the weekdays. By averaging the metal leakage ratio in various climates and the average weight of cigarette butts, we were able to estimate the total amount of heavy metal leakage. The findings revealed that the annual average value of the index for the areas that were investigated ranged from 1.38 to 10.4. According to these numbers, just 27.5% of the areas had a low pollution rating, while 43.5% had a major pollution status or worse. Weekends witnessed the largest fall (31% on average) in all locations' indices, while spring and summer saw the largest increase (26% on average) compared to autumn and winter. It was calculated that the average amount of heavy metals such as Cr, Cu, Cd, Zn, and Pb that seep into the environment from discarded cigarette butts in commercial, residential, and park areas, respectively, is 0.25 µg/m2, 0.078 µg/m2, and 0.18 µg/m2. Butt from cigarettes is one of the most prevalent forms of litter in the area that was examined. This litter is the origin of a wide variety of contaminants, including heavy metals. This toxic garbage poses a significant risk to the city.

Keywords: heavy metal, hazardous waste, waste management, litter

Procedia PDF Downloads 80

Authors: Ruttayaporn Ngasaman, Saowakon Indouang, Usa Chethanond

Abstract:

Leptospirosis is a public health concern zoonosis in Thailand. Human and animals are often infected by contact with contaminated water. The infected animals play an important role in leptospira infection for both human and other hosts via urine. In humans, it can cause a wide range of symptoms, some of which may present mild flu-like symptoms including fever, vomiting, and jaundice. Without treatment, Leptospirosis can lead to kidney damage, meningitis, liver failure, respiratory distress, and even death. The prevalence of leptospirosis in stray animals in Thailand is unknown. The aim of this study was to investigate leptospira infection in stray animals including dogs and cats in Songkhla province, Thailand. Total of 434 blood samples were collected from 370 stray dogs and 64 stray cats during the population control program from 2014 to 2018. Screening test using latex agglutination for the detection of antibodies against Leptospira interrogans in serum samples shows 29.26% (127/434) positive. There were 120 positive samples of stray dogs and 7 positive samples of stray cats. Detection by polymerase chain reaction specific to LipL32 gene of Leptospira interrogans showed 1.61% (7/434) positive. Stray cats (5/64) show higher prevalence than stray dogs (2/370). Although active infection was low detected, but seroprevalence was high. This result indicated that stray animals were not active infection during sample collection but they use to get infected or in a latent period of infection. They may act as a reservoir for domestic animals and human in which stay in the same environment. In order to prevent and reduce the risk of leptospira infection in a human, stray animals should be done health checking, vaccination, and disease treatment.

Keywords: leptospirosis, stray animals, risk reduction, Thailand

Procedia PDF Downloads 133