Search results for: regional cerebral oxygen saturation

Authors: M. François, L. Sigot, C. Vallières

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Volatile Organic Compounds (VOCs) are a real health issue, particularly in domestic indoor environments. Among these VOCs, acetaldehyde is frequently monitored in dwellings ‘air, especially due to smoking and spontaneous emissions from the new wall and soil coverings. It is responsible for respiratory complaints and is classified as possibly carcinogenic to humans. Adsorption processes are commonly used to remove VOCs from the air. Metal-Organic Frameworks (MOFs) are a promising type of material for high adsorption performance. These hybrid porous materials composed of metal inorganic clusters and organic ligands are interesting thanks to their high porosity and surface area. The HKUST-1 (also referred to as MOF-199) is a copper-based MOF with the formula [Cu₃(BTC)₂(H₂O)₃]n (BTC = benzene-1,3,5-tricarboxylate) and exhibits unsaturated metal sites that can be attractive sites for adsorption. The objective of this study is to investigate the impact of HKUST-1 pretreatment on acetaldehyde adsorption. Thus, dynamic adsorption experiments were conducted in 1 cm diameter glass column packed with 2 cm MOF bed height. MOF were sieved to 630 µm - 1 mm. The feed gas (Co = 460 ppmv ± 5 ppmv) was obtained by diluting a 1000 ppmv acetaldehyde gas cylinder in air. The gas flow rate was set to 0.7 L/min (to guarantee a suitable linear velocity). Acetaldehyde concentration was monitored online by gas chromatography coupled with a flame ionization detector (GC-FID). Breakthrough curves must allow to understand the interactions between the MOF and the pollutant as well as the impact of the HKUST-1 humidity in the adsorption process. Consequently, different MOF water content conditions were tested, from a dry material with 7 % water content (dark blue color) to water saturated state with approximately 35 % water content (turquoise color). The rough material – without any pretreatment – containing 30 % water serves as a reference. First, conclusions can be drawn from the comparison of the evolution of the ratio of the column outlet concentration (C) on the inlet concentration (Co) as a function of time for different HKUST-1 pretreatments. The shape of the breakthrough curves is significantly different. The saturation of the rough material is slower (20 h to reach saturation) than that of the dried material (2 h). However, the breakthrough time defined for C/Co = 10 % appears earlier in the case of the rough material (0.75 h) compared to the dried HKUST-1 (1.4 h). Another notable difference is the shape of the curve before the breakthrough at 10 %. An abrupt increase of the outlet concentration is observed for the material with the lower humidity in comparison to a smooth increase for the rough material. Thus, the water content plays a significant role on the breakthrough kinetics. This study aims to understand what can explain the shape of the breakthrough curves associated to the pretreatments of HKUST-1 and which mechanisms take place in the adsorption process between the MOF, the pollutant, and the water.

Keywords: acetaldehyde, dynamic adsorption, HKUST-1, pretreatment influence

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Authors: S.Pandeeswari, Raju Padma

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In this paper a new solution to implement and control single-stage electronic ballast based on the integration of a buck-boost power factor correction stage and a half bridge resonant inverter is presented. The control signals are obtained using the inverter resonant current by means of a saturable transformer. Core saturation is used to control the required dead time between the control pulses on both switches. The turn-on time of one of the inverter switches is controlled to provide proper cathode preheating during the lamp ignition process. No special integrated circuits are required to control the ballast and the total number of components is minimized. Analysis and basic design of phase cut dimmer.

Keywords: MOSFET dimmer, PIC 16F877A, voltage regulator, bridge rectifier

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Authors: Sajjad Shojaeidoust, Mohsen Ghanbarzadeh, Abdolhamid Habibi

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Exercise-induced bronchospasm (EIB) is a transitory condition of airflow obstruction that is associated with physical activities. It is noted that high ventilation can lead to an increase in the heat and reduce in the moisture in airways resistance of trachea. Also causes of pathophysiological mechanism are EIB. Accordingly, studying some parameters of pulmonary function (FVC, FEV1) among active people seems quintessential. The aim of this study was to analyze bronchospasm following the implementation of a program of maximum aerobic exercise in active men at Chamran University of Ahwaz. Method: In this quasi-experimental study, the population consisted of all students at Chamran University. Among from 55 participants, of which, 15 were randomly selected as the experimental group. In this study, the size of the maximum oxygen consumption was initially measured, and then, based on the maximum oxygen consumed, the active individuals were identified. After five minutes’ warm-up, Strand treadmill exercise test was taken (one session) and pulmonary parameters were measured at both pre- and post-tests (spirometer). After data normalization using KS and non-normality of the data, the Wilcoxon test was used to analyze the data. The significance level for all statistical surveys was considered p≤0/05. Results: The results showed that the ventilation factors and bronchospasm (FVC, FEV1) in the pre-test and post-test resulted in no significant difference among the active people (p≥0/05). Discussion and conclusion: Based on the results observed in this study, it appears that pulmonary indices in active individuals increased after aerobic test. The increase in this indicator in active people is due to increased volume and elasticity of the lungs as well. In other words, pulmonary index is affected by rib muscles. It is considered that progress over respiratory muscle strength and endurance has raised FEV1 in the active cases.

Keywords: aerobic active maximum, bronchospasm, pulmonary function, spirometer

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Authors: Pureun-Haneul Lee, Byeong-Gon Kim, Sun-Hye Lee, An-Soo Jang

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Background: Nanoparticles may pose adverse health effects due to particulate matter inhalation. Nanoparticle exposure induces cell and tissue damage, causing local and systemic inflammatory responses. The inflammasome is a major regulator of inflammation through its activation of pro-caspase-1, which cleaves pro-interleukin-1β (IL-1β) into its mature form and may signal acute and chronic immune responses to nanoparticles. Objective: The aim of the study was to identify whether nanoparticles exaggerates inflammasome pathway leading to airway inflammation and hyperresponsiveness in an allergic mice model of asthma. Methods: Mice were treated with saline (sham), OVA-sensitized and challenged (OVA), or titanium dioxide nanoparticles. Lung interleukin 1 beta (IL-1β), interleukin 18 (IL-18), NACHT, LRR and PYD domains-containing protein 3 (NLRP3) and caspase-1 levels were assessed with Western Blot. Caspase-1 was checked by immunohistochemical staining. Reactive oxygen species were measured for the marker 8-isoprostane and carbonyl by ELISA. Results: Airway inflammation and hyperresponsiveness increased in OVA-sensitized/challenged mice and these responses were exaggerated by TiO2 nanoparticles exposure. TiO2 nanoparticles treatment increased IL-1β and IL-18 protein expression in OVA-sensitized/challenged mice. TiO2 nanoparticles augmented the expression of NLRP3 and caspase-1 leading to the formation of an active caspase-1 in the lung. Lung caspase-1 expression was increased in OVA-sensitized/challenged mice and these responses were exaggerated by TiO2 nanoparticles exposure. Reactive oxygen species was increased in OVA-sensitized/challenged mice and in OVA-sensitized/challenged plus TiO2 exposed mice. Conclusion: Our data demonstrate that inflammasome pathway activates in asthmatic lungs following nanoparticles exposure, suggesting that targeting the inflammasome may help control nanoparticles-induced airway inflammation and responsiveness.

Keywords: bronchial asthma, inflammation, inflammasome, nanoparticles

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Authors: Abdullah Al-Mamun, Md. Nuruzzaman, Md. Noor Salleh, Muhammad Abu Eusuf, Ahmad Jalal Khan Chowdhury, Mohd. Zaki M. Amin, Norlida Mohd. Dom

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Identification of pollution sources and determination of pollution loads from all areas are very important for sustainable rehabilitation of any contaminated river. Pusu is a small river which, flows through the main campus of International Islamic University Malaysia (IIUM) at Gombak. Poor aesthetics of the river, which is flowing through the entrance of the campus, gives negative impression to the local and international visitors. As such, this study is being conducted to find ways to rehabilitate the river in a sustainable manner. The point and non-point pollution sources of the river basin are identified. Upper part of the 12.6 km2 river basin is covered with secondary forest. However, it is the lower-middle reaches of the river basin which is being cleared for residential development and source of high sediment load. Flow and concentrations of the common pollutants, important for a healthy river, such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Suspended Solids (SS), Turbidity, pH, Ammoniacal Nitrogen (AN), Total Nitrogen (TN) and Total Phosphorus (TP) are determined. Annual pollution loading to the river was calculated based on the primary and secondary data. Concentrations of SS were high during the rainy day due to contribution from the non-point sources. There are 7 ponds along the river system within the campus, which are severely affected by high sediment load from the land clearing activities. On the other hand, concentrations of other pollutants were high during the non-rainy days. The main sources of point pollution are the hostels, cafeterias, sewage treatment plants located in the campus. Therefore, both pollution sources need to be controlled in order to rehabilitate the river in a sustainable manner.

Keywords: river pollution, rehabilitation, point pollution source, non-point pollution sources, pollution loading

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Authors: Khan R. Rahaman, Quazi K. Hassan

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Global changes in climate, environment, economies, populations, governments, institutions, and cultures converge in localities. Changes at a local scale, in turn, contribute to global changes as well as being affected by them. Our hypothesis is built on a consideration that temperature does vary at local level (i.e., termed as local warming) in comparison to the predicted models at the regional and/or global scale. To date, the bulk of the research relating local places to global climate change has been top-down, from the global toward the local, concentrating on methods of impact analysis that use as a starting point climate change scenarios derived from global models, even though these have little regional or local specificity. Thus, our focus is to understand such trends over the southern Alberta, which will enable decision makers, scientists, researcher community, and local people to adapt their policies based on local level temperature variations and to act accordingly. Specific objectives in this study are: (i) to understand the local warming (temperature in particular) trend in context of temperature normal during the period 1961-2010 at point locations using meteorological data; (ii) to validate the data by using specific yearly data, and (iii) to delineate the spatial extent of the local warming trends and understanding influential factors to adopt situation by local governments. Existing data has brought the evidence of such changes and future research emphasis will be given to validate this hypothesis based on remotely sensed data (i.e. MODIS product by NASA).

Keywords: local warming, climate change, urban area, Alberta, Canada

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Authors: Aicha Assal, El Mostapha Lotfi

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Rapid industrialization and population growth are currently the main causes of energy and environmental problems associated with wastewater treatment. Wastewater treatment plants (WWTPs) aim to treat wastewater before discharging it into the environment, but they are not yet capable of treating non-biodegradable contaminants such as heavy metals. Toxic heavy metals can disrupt biological processes in WWTPs. Consequently, it is crucial to combine additional physico-chemical treatments with WWTPs to ensure effective wastewater treatment. In this study, the authors examined the pretreatment process for urban wastewater generated by the El Jadida WWTP in order to assess its treatment efficiency. Various physicochemical and spatiotemporal parameters of the WWTP's raw and treated water were studied, including temperature, pH, conductivity, biochemical oxygen demand (BOD5), chemical oxygen demand (COD), suspended solids (SS), total nitrogen, and total phosphorus. The results showed an improvement in treatment yields, with measured performance values of 77% for BOD5, 63% for COD, and 66% for TSS. However, spectroscopic analyses revealed persistent coloration in wastewater samples leaving the WWTP, as well as the presence of heavy metals such as Zn, cadmium, chromium, and cobalt, detected by inductively coupled plasma optical emission spectroscopy (ICP-OES). To remedy these staining problems and reduce the presence of heavy metals, a new low-cost, environmentally-friendly eggshell-based solution was proposed. This method eliminated most heavy metals such as cobalt, beryllium, silver, and copper and significantly reduced the amount of cadmium, lead, chromium, manganese, aluminium, and Zn. In addition, the bioadsorbent was able to decolorize wastewater by up to 84%. This adsorption process is, therefore, of great interest for ensuring the quality of wastewater and promoting its reuse in irrigation.

Keywords: WWTP, wastewater, heavy metals, decoloration, depollution, COD, BOD5

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Authors: Camilo Andres Agudelo-Velez, Lina María Martinez-Sanchez, Natalia Perilla-Hernandez, Maria De Los Angeles Rodriguez-Gazquez, Felipe Hernandez-Restrepo, Dayana Andrea Quintero-Moreno, Camilo Ruiz-Mejia, Isabel Cristina Ortiz-Trujillo, Monica Maria Zuluaga-Quintero

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Chronic obstructive pulmonary disease is common condition, characterized by a persistent blockage of airflow, partially reversible and progressive, that represents 5% of total deaths around the world, and it is expected to become the third leading cause of death by 2030. Objective: To establish the clinical and epidemiological profile of patients with chronic obstructive pulmonary disease in a medical institution from the city of Medellin, Colombia. Methods: A cross-sectional study was performed, with a sample of 50 patients with a diagnosis of chronic obstructive pulmonary disease in a private institution in Medellin, during 2015. The software SPSS vr. 20 was used for the statistical analysis. For the quantitative variables, averages, standard deviations, and maximun and minimun values were calculated, while for ordinal and nominal qualitative variables, proportions were estimated. Results: The average age was 73.5±9.3 years, 52% of the patients were women, 50% of them had retired, 46% ere married and 80% lived in the city of Medellín. The mean time of diagnosis was 7.8±1.3 years and 100% of the patients were treated at the internal medicine service. The most common clinical features were: 36% were classified as class D for the disease, 34% had a FEV1 <30%, 88% had a history of smoking and 52% had oxygen therapy at home. Conclusion: It was found that class D was the most common, and the majority of the patients had a history of smoking, indicating the need to strengthen promotion and prevention strategies in this regard.

Keywords: pulmonary disease, chronic obstructive, pulmonary medicine, oxygen inhalation therapy

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Authors: R. Ziaie Moayed, M. Alibolandi

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Dynamic behavior of soil are evaluated relative to a number of factors including: strain level, density, number of cycles, material type, fine content, geosynthetic inclusion, saturation, and effective stress. This paper investigate the dynamic behavior of saturated reinforced sand under cyclic stress condition. The cyclic triaxial tests are conducted on remolded specimens under various CSR which reinforced by different arrangement of non-woven geotextile. Aforementioned tests simulate field reinforced saturated deposits during earthquake or other cyclic loadings. This analysis revealed that the geotextile arrangement played dominant role on dynamic soil behavior and as geotextile close to top of specimen, the liquefaction resistance increased.

Keywords: dynamic behavior, reinforced sand, triaxial test, non-woven geotextile

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Authors: Eva Tvrdá, Boris Botman, Marek Halenár, Tomáš Slanina, Norbert Lukáč

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In vitro storage and processing of animal semen represents a risk factor to spermatozoa vitality, potentially leading to reduced fertility. A variety of substances isolated from natural sources may exhibit protective or antioxidant properties on the spermatozoon, thus extending the lifespan of stored ejaculates. This study compared the ability of different concentrations of the Salvia officinalis extract on the motility, mitochondrial activity, viability and reactive oxygen species (ROS) production by bovine spermatozoa during different time periods (0, 2, 6 and 24 h) of in vitro culture. Spermatozoa motility was assessed using the Computer-assisted sperm analysis (CASA) system. Cell viability was examined using the metabolic activity MTT assay, the eosin-nigrosin staining technique was used to evaluate the sperm viability and ROS generation was quantified using luminometry. The CASA analysis revealed that the motility in the experimental groups supplemented with 0.5-2 µg/mL Salvia extract was significantly lower in comparison with the control (P<0.05; Time 24 h). At the same time, a long-term exposure of spermatozoa to concentrations ranging between 0.05 µg/mL and 2 µg/mL had a negative impact on the mitochondrial metabolism (P<0.05; Time 24 h). The viability staining revealed that 0.001-1 µg/mL Salvia extract had no effects on bovine male gametes, however 2 µg/mL Salvia had a persisting negative effect on spermatozoa (P<0.05). Furthermore 0.05-2 µg/mL Salvia exhibited an immediate ROS-promoting effect on the sperm culture (P>0.05; Time 0 h and 2 h), which remained significant throughout the entire in vitro culture (P<0.05; Time 24 h). Our results point out to the necessity to examine specific effects the biomolecules present in Salvia officinalis may have individually or collectively on the in vitro sperm vitality and oxidative profile.

Keywords: bulls, CASA, MTT test, reactive oxygen species, sage, Salvia officinalis, spermatozoa

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Authors: Farhad Nouparast

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For more production we need more capital formation. Capital formation in each country should be based on comparative advantages in different economic sectors due to the different production possibility curves. In regional planning, recognizing the relative advantages and consequently investing in more production requires identifying areas with the necessary capabilities and location of each region compared to other regions. In this article, ranking of Iran's provinces is done according to the specific and given variables as the best investment position in agricultural activity. So we can provide the necessary background for investment analysis in different regions of the country to formulate national and regional planning and execute investment projects. It is used factor analysis technique and numerical taxonomy analysis to do this in thisarticle. At first, the provinces are homogenized and graded according to the variables using cross-sectional data obtained from the agricultural census and population and housing census of Iran as data matrix. The results show that which provinces have the most potential for capital formation in agronomy sub-sector. Taxonomy classifies organisms based on similar genetic traits in biology and botany. Numerical taxonomy using quantitative methods controls large amounts of information and get the number of samples and categories and take them based on inherent characteristics and differences indirectly accommodates. Numerical taxonomy is related to multivariate statistics.

Keywords: Capital Formation, Factor Analysis, Multivariate statistics, Numerical Taxonomy Analysis, Production, Ranking, Spatial Planning

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Authors: A. Paz, S. Cortés Diéguez, J. M. Cruz, A. B. Moldes, J. M. Domínguez

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Synthetic dyes are extensively used in the paper, food, leather, cosmetics, pharmaceutical and textile industries. Wastewater resulting from their production means several environmental problems. Improper disposal of theirs effluents involves adverse impacts and not only about the colour, also on water quality (Total Organic Carbon, Biological Oxygen Demand, Chemical Oxygen Demand, suspended solids, salinity, etc.) on flora (inhibition of photosynthetic activity), fauna (toxic, carcinogenic, and mutagenic effects) and human health. The aim of this work is to optimize the decolourisation process of different types of dyes by Bacillus aryabhattai. Initially, different types of dyes (Indigo Carmine, Coomassie Brilliant Blue and Remazol Brilliant Blue R) and suitable culture media (Nutritive Broth, Luria Bertani Broth and Trypticasein Soy Broth) were selected. Then, a central composite design (CCD) was employed to optimise and analyse the significance of each abiotic parameter. Three process variables (temperature, salt concentration and agitation) were investigated in the CCD at 3 levels with 2-star points. A total of 23 experiments were carried out according to a full factorial design, consisting of 8 factorial experiments (coded to the usual ± 1 notation), 6 axial experiments (on the axis at a distance of ± α from the centre), and 9 replicates (at the centre of the experimental domain). Experiments results suggest the efficiency of this strain to remove the tested dyes on the 3 media studied, although Trypticasein Soy Broth (TSB) was the most suitable medium. Indigo Carmine and Coomassie Brilliant Blue at maximal tested concentration 150 mg/l were completely decolourised, meanwhile, an acceptable removal was observed using the more complicate dye Remazol Brilliant Blue R at a concentration of 50 mg/l.

Keywords: Bacillus aryabhattai, dyes, decolourisation, central composite design

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Authors: Adekunle Saheed Ajisebiyawo

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This paper examines the influence of identity politics on the development of electoral democracy in Nigeria. The paper was anchored on a theory of African democracy adopted the qualitative methodology and deployed data from secondary sources to evaluate the 2023 presidential election, and found that ethnicity, religion, and regional sentiments played a major role in the election. The practical implications of this paper are that while Nigeria’s democracy is tending towards consolidation, if the unexpected does not happen, e.g., military takeover, religious and ethnic identities can mar the country’s development as competent candidates that have good policies will be voted out based on religious and ethnic sentiments. Thus, there is a need to de-emphasize religion and ethnicity in the Nigerian polity. Candidates and parties that campaign based on racial or religious narratives should be barred from contesting elective positions. The paper concluded that identity politics is inimical to Nigeria’s democratization process as well as efforts aimed at uniting and integrating the country; it, therefore, recommended that to establish a sound electoral democracy and a strong united country, the menace of ethnic, religious, and regional cleavages should be addressed. To achieve this, efforts should be intensified towards providing a set of principles for nation-building which should be included in the constitution. In addition, the paper urges the media to support the formation of an inclusive government, cutting across tribes and religions in the country to reduce the negative impact of ethnicity and religion in the country.

Keywords: cleavages, democracy, ethnicity, election, identity politics, religion

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Authors: S. Hutasavi, D. Chen

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The built-up area is a significant proxy to measure regional economic growth and reflects the Gross Provincial Product (GPP). However, an up-to-date and reliable database of built-up areas is not always available, especially in developing countries. The cloud-based geospatial analysis platform such as Google Earth Engine (GEE) provides an opportunity with accessibility and computational power for those countries to generate the built-up data. Therefore, this study aims to extract the built-up areas in Eastern Economic Corridor (EEC), Thailand using day and nighttime satellite imagery based on GEE facilities. The normalized indices were generated from Landsat 8 surface reflectance dataset, including Normalized Difference Built-up Index (NDBI), Built-up Index (BUI), and Modified Built-up Index (MBUI). These indices were applied to identify built-up areas in EEC. The result shows that MBUI performs better than BUI and NDBI, with the highest accuracy of 0.85 and Kappa of 0.82. Moreover, the overall accuracy of classification was improved from 79% to 90%, and error of total built-up area was decreased from 29% to 0.7%, after night-time light data from the Visible and Infrared Imaging Suite (VIIRS) Day Night Band (DNB). The results suggest that MBUI with night-time light imagery is appropriate for built-up area extraction and be utilize for further study of socioeconomic impacts of regional development policy over the EEC region.

Keywords: built-up area extraction, google earth engine, adaptive thresholding method, rapid mapping

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Authors: Giorgi Sulashvili, Vladimer Kekenadze, Olga Khutsishvili, Bela Khotenashvili, Tsiuri Phkhakadze, Besarion Tsikhelashvili

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The article dealt with the South Caucasus is a complex economic policy, which consists of strands: The process of deepening economic integration in the South Caucasus region; deepening economic integration with the EU in the framework of "Neighbourhood policy with Europe" and in line with the Maastricht criteria; the development of bilateral trade and economic relations with many countries of the world community; the development of sufficient conditions for the integration of the South Caucasus region in the world to enter the market. According to the author, to determine the place of Georgia in the regional policy of the South Caucasus, it is necessary to consider two views about Georgia: The first is the view of Georgia, as a part of global economic and political processes and the second look at Georgia, as a country located in the geo-economic and geopolitical space of the South Caucasus. Such approaches reveal the place of Georgia in two dimensions; in the global and regional economies. In the countries of South Caucasus, the tourism has been developing fast and has a great social and economic importance. Tourism influences deeply on the social and economic growth of the regions of the country. Tourism development formulates thousand new jobs, fixes the positions of small and middle businesses, ensures the development of the education and culture of the population. In the countries of South Caucasus, the Tourist Industry can be specified as the intersectoral complex, which consists of travel transport and it’s technical service network, tourist enterprises which are specialized in various types, wide network services. Tourists have a chance to enjoy all of these services. At the transitional stage of shifting to the market economy, tourism is among the priorities in the development of the national economy of our country. It is true that the Georgian tourism faces a range of problems at present, but its recognition and the necessity for its development may be considered as a fact. Besides, we would underline that the revitalization of the Georgian tourism is not only the question of time. This area can bring a lot of benefits as to private firms, as to specific countries. It also has many negative effects were conducted fundamental research and studies to consider both, positive and negative impacts of tourism. In the future such decisions will be taken that will bring, the maximum benefit at minimum cost, in order for tourism to take its place in Georgia it is necessary to understand the role of the tourism sector in the economic structure.

Keywords: transitional stage, national economy, Georgian tourism, positive and negative impacts

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Authors: Peter M. Schneider, Batyr Garlyyev, Sebastian A. Watzele, Aliaksandr S. Bandarenka

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Functional nanostructures such as nanoparticles are a promising class of materials for energy applications due to their unique properties. Bottom-up synthetic routes for nanostructured materials often involve multiple synthesis steps and the use of surfactants, reducing agents, or stabilizers. This results in complex and extensive synthesis protocols. In recent years, a novel top-down synthesis approach to form metal nanoparticles has been established, in which bulk metal wires are immersed in an electrolyte (primarily alkali earth metal based) and subsequently subjected to a high alternating potential. This leads to the generation of nanoparticles dispersed in the electrolyte. The main advantage of this facile top-down approach is that there are no reducing agents, surfactants, or precursor solutions. The complete synthesis can be performed in one pot involving one main step with consequent washing and drying of the nanoparticles. More recent studies investigated the effect of synthesis parameters such as potential amplitude, frequency, electrolyte composition, and concentration on the size and shape of the nanoparticles. Here, we investigate the electrochemical erosion of various metal wires such as Ti, Pt, Pd, and Sn in various electrolyte compositions via this facile top-down technique and its experimental optimization to successfully synthesize nanostructured materials for various energy applications. As an example, for Pt and Pd, homogeneously distributed nanoparticles on carbon support can be obtained. These materials can be used as electrocatalyst materials for the oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER), respectively. In comparison, the top-down erosion of Sn wires leads to the formation of nanoparticles, which have great potential as oxygen evolution reaction (OER) support materials. The application of the technique on Ti wires surprisingly leads to the formation of nanowires, which show a high surface area and demonstrate great potential as an alternative support material to carbon.

Keywords: ORR, electrochemistry, electrocatalyst, synthesis

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Authors: I-Han Hsiao, Chun-Ping Huang, Ching-Liang Hsieh, Yi-Wen Lin

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Epilepsy is chronic brain disorder that results in the sporadic occurrence of spontaneous seizures in the temporal lobe, cerebral cortex, and hippocampus. Clinical antiepileptic medicines are often ineffective or little benefits in the small amount of patients and usually initiate severe side effects. This inflammation contributes to enhanced neuronal excitability and the onset of epilepsy. Auricular electric-stimulation (AES) can increase parasympathetic activity and stimulate the solitary tract nucleus to induce the cholinergic anti-inflammatory pathway. Furthermore, it may be a therapeutic strategy for the treatment of epilepsy. In the present study, we want to investigate the effects of AES on inflammatory mediators in kainic acid (KA)-induced epileptic seizure rats. Experimental KA injection increased expression of TLR-2 pathway associated inflammatory mediators, were further reduced by either 2Hz or 15 Hz AES in the prefrontal cortex, hippocampus, and somatosensory cortex. We suggest that AES can successfully control the epileptic seizure by down-regulation of inflammation signaling pathway.

Keywords: auricular electric-stimulation, epileptic seizures, anti-inflammation

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Authors: Yun-na Wu, Zhen Wang

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Due to the economic downturn and the deterioration of the living environment, the development of residential buildings as high energy consuming building is gradually changing from “extensive” to green building in China. So, the evaluation system of green building is continuously improved, but the current evaluation work has the following problems: (1) There are differences in the cost of the actual investment and the purchasing power of residents, also construction target of green residential building is single and lacks multi-objective performance development. (2) Green building evaluation lacks regional characteristics and cannot reflect the different regional residents demand. (3) In the process of determining the criteria weight, the experts’ judgment matrix is difficult to meet the requirement of consistency. Therefore, to solve those problems, questionnaires which are about the green residential building for Ningxia area are distributed, and the results of questionnaires can feedback the purchasing power of residents and the acceptance of the green building cost. Secondly, combined with the geographical features of Ningxia minority areas, the evaluation criteria system of green residential building is constructed. Finally, using the improved group AHP method and the grey clustering method, the criteria weight is determined, and a real case is evaluated, which is located in Xing Qing district, Ningxia. A conclusion can be obtained that the professional evaluation for this project and good social recognition is basically the same.

Keywords: evaluation, green residential building, grey clustering method, group AHP

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Authors: M. M. Mekkakia, M. P Luong, A. Arab

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These controlling the water content of compaction are a major concern of fundamental civil engineers. Also, the knowledge of the fundamentals of the behaviour of compacted clay soils is essential to predict and quantify the effects of a change in water content. The study of unsaturated soils is a very complex area which several studies are directed to in recent years. Our job work is to perform tests of Proctor, Oedometer and shear, on samples of unsaturated clay in order to see the influence of water content on the compressibility and the shear strength. The samples were prepared at different amounts of water from water content to optimum water contents close to saturation. This study thus allowed us to measure and monitor the parameters of compressibility and shear strength as a function of water content.

Keywords: laboratory tests, clay, unsaturated soil, atterberg limits, compaction, compressibility, shear

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Authors: Mohsen Khaledian, Razali Ismail, Mehdi Saeidmanesh, Mahdiar Hosseinghadiry

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A semi-analytical model for impact ionization coefficient of graphene nanoribbon (GNR) is presented. The model is derived by calculating probability of electrons reaching ionization threshold energy Et and the distance traveled by electron gaining Et. In addition, ionization threshold energy is semi-analytically modeled for GNR. We justify our assumptions using analytic modeling and comparison with simulation results. Gaussian simulator together with analytical modeling is used in order to calculate ionization threshold energy and Kinetic Monte Carlo is employed to calculate ionization coefficient and verify the analytical results. Finally, the profile of ionization is presented using the proposed models and simulation and the results are compared with that of silicon.

Keywords: nanostructures, electronic transport, semiconductor modeling, systems engineering

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Authors: Sheila Shahidi, Hootan Rezaee, Abosaeed Rashidi, Mahmood Ghoranneviss

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Plasma treatment has an explosive increase in interest and use in industrial applications as for example in medical, biomedical, automobile, electronics, semiconductor and textile industry. A lot of intensive basic research has been performed in the last decade in the field of textiles along with technical textiles. Textile manufacturers and end-users alike have been searching for ways to improve the surface properties of natural and man-made fibers. Specifically, there is a need to improve adhesion and wettability. Functional groups may be introduced onto the fiber surface by using gas plasma treatments, improving fiber surface properties without affecting the fiber’s bulk properties. In this research work, ZnO nanoparticles (ZnO-NPs) were insitue synthesized by sonochemical method at room temperature on both untreated and plasma pretreated cotton woven fabric. Oxygen and nitrogen plasmas were used for pre-functionalization of cotton fabric. And the effect of oxygen and nitrogen pre-functionalization on adhesion properties between ZnO nanoparticles and cotton surface were studied. The results show that nanoparticles with average sizes of 20-100 nm with different morphologies have been created on the surface of samples. Synthesis of ZnO-NPs was varied in the morphological transformation by changes in zinc acetate dehydrate concentration. Characterizations were carried out using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Inductive coupled plasma (ICP) and Spectrophotometery. The antibacterial activities of the fabrics were assessed semi-quantitatively by the colonies count method. The results show that the finished fabric demonstrated significant antibacterial activity against S. aureus in antibacterial test. The wash fastness of both untreated and plasma pretreated samples after 30 times of washing was investigated. The results showed that the parameters of plasma reactor plays very important role for improving the antibacterial durability.

Keywords: antibacterial activity, cotton, fabric, nanoparticles, plasma

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Authors: Artem Kim, Clara Savary, Christele Dubourg, Wilfrid Carre, Houda Hamdi-Roze, Valerie Dupé, Sylvie Odent, Marie De Tayrac, Veronique David

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Holoprosencephaly (HPE) is a rare congenital brain malformation resulting from the incomplete separation of the two cerebral hemispheres. It is characterized by a wide phenotypic spectrum and a high degree of locus heterogeneity. Genetic defects in 16 genes have already been implicated in HPE, but account for only 30% of cases, suggesting that a large part of genetic factors remains to be discovered. HPE has been recently redefined as a complex multigenic disorder, requiring the joint effect of multiple mutational events in genes belonging to one or several developmental pathways. The onset of HPE may result from accumulation of the effects of multiple rare variants in functionally-related genes, each conferring a moderate increase in the risk of HPE onset. In order to decipher the genetic basis of HPE, unconventional patterns of inheritance involving multiple genetic factors need to be considered. The primary objective of this study was to uncover possible disease causing combinations of multiple rare variants underlying HPE by performing trio-based Whole Exome Sequencing (WES) of familial cases where no molecular diagnosis could be established. 39 families were selected with no fully-penetrant causal mutation in known HPE gene, no chromosomic aberrations/copy number variants and without any implication of environmental factors. As the main challenge was to identify disease-related variants among a large number of nonpathogenic polymorphisms detected by WES classical scheme, a novel variant prioritization approach was established. It combined WES filtering with complementary gene-level approaches: transcriptome-driven (RNA-Seq data) and clinically-driven (public clinical data) strategies. Briefly, a filtering approach was performed to select variants compatible with disease segregation, population frequency and pathogenicity prediction to identify an exhaustive list of rare deleterious variants. The exome search space was then reduced by restricting the analysis to candidate genes identified by either transcriptome-driven strategy (genes sharing highly similar expression patterns with known HPE genes during cerebral development) or clinically-driven strategy (genes associated to phenotypes of interest overlapping with HPE). Deeper analyses of candidate variants were then performed on a family-by-family basis. These included the exploration of clinical information, expression studies, variant characteristics, recurrence of mutated genes and available biological knowledge. A novel bioinformatics pipeline was designed. Applied to the 39 families, this final integrated workflow identified an average of 11 candidate variants per family. Most of candidate variants were inherited from asymptomatic parents suggesting a multigenic inheritance pattern requiring the association of multiple mutational events. The manual analysis highlighted 5 new strong HPE candidate genes showing recurrences in distinct families. Functional validations of these genes are foreseen.

Keywords: complex genetic disorder, holoprosencephaly, multiple rare variants, whole exome sequencing

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Authors: Ravinder Reddy Butreddy, Sadhana Katlakunta

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The nanocomposites of CoFe2O4-xZrO2 with different loadings of ZrO2 (x = 0.025, 0.05, 0.075, 0.1 and 1.5) were prepared using ball mill method. All the samples were prepared at 980°C/1h using microwave sintering method. The x-ray diffraction patterns show the existence of tetragonal/monoclinic phase of ZrO2 and cubic phase of CoFe2O4. The effects of ZrO2 on structural and microstructural properties of CoFe2O4 composite ceramics were investigated. It is observed that the density of the composite decreases and porosity increases with x. The magnetic properties such as saturation magnetization (Ms), and Coercive field were calculated at room temperature. The Ms is decreased with x while coercive field is increased with x. The dielectric parameters exhibit the relaxation behavior in high-frequency region and showing increasing trend with ZrO2 concentration, showing suitable

Keywords: dielectric properties, magnetic properties, microwave sintering, nanocomposites

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Authors: Zue Chin Chang, Shih-Chang Liang

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RF magnetron sputtering is used on the ceramic targets, each of which contains zinc oxide (ZnO), zinc oxide doped with aluminum (AZO) and zinc oxide doped with gallium (GZO). The electric conduction mechanism of the AZO and GZO films came mainly from the Al and Ga, the oxygen vacancies, Zn interstitial atoms, and Al and/or Ga interstitial atoms. AZO and GZO films achieved higher conduction than did ZnO film, it being ion vacant and nonstoichiometric. The XRD analysis showed a preferred orientation along the (002) plane for ZnO, AZO, and GZO films.

Keywords: ZnO, AZO, GZO, doped, sputtering

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Authors: Zhao Weijie, Lin Xinjian, Liu Xiaojuan, Li Lihua

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The Howland current pump is widely used in bio-impedance measurement. Much attention has been focused on the output impedance of the Howland circuit. Here we focus on the maximum load of the Howland source and discuss the relationship between the circuit parameters at maximum load. We conclude that the signal input terminal of the feedback resistor should be as large as possible, but that the current-limiting resistor should be smaller. The op-amp saturation voltage should also be high. The bandwidth of the circuit is proportional to the bandwidth of the op-amp. The Howland current pump was simulated using multisim12. When the AD8066AR was selected as the op-amp, the maximum load was 11.5 kΩ, and the Howland current pump had a stable output ipp to 2mAp up to 200 kHz. However, with an OPA847 op-amp and a load of 6.3 kΩ, the output current was also stable, and the frequency was as high as 3 MHz.

Keywords: bio-impedance, improved Howland current pump, load characteristics, bioengineering

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Authors: Moustafa Osman Mohammed

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This paper is mapping air quality model to engineering the industrial system that ultimately utilized in extensive range of energy systems, distribution resources, and end-user technologies. The model is determining long-range transport patterns contribution as area source can either traced from 48 hrs backward trajectory model or remotely described from background measurements data in those days. The trajectory model will be run within stable conditions and quite constant parameters of the atmospheric pressure at the most time of the year. Air parcel trajectory is necessary for estimating the long-range transport of pollutants and other chemical species. It provides a better understanding of airflow patterns. Since a large amount of meteorological data and a great number of calculations are required to drive trajectory, it will be very useful to apply HYPSLIT model to locate areas and boundaries influence air quality at regional location of Windsor. 2–days backward trajectories model at high and low concentration measurements below and upward the benchmark which was areas influence air quality measurement levels. The benchmark level will be considered as 30 (μg/m3) as the moderate level for Ontario region. Thereby, air quality model is incorporating a midpoint concept between biotic and abiotic components to broaden the scope of quantification impact. The later outcomes’ theories of environmental obligation suggest either a recommendation or a decision of what is a legislative should be achieved in mitigation measures of air emission impact ultimately.

Keywords: air quality, management systems, environmental impact assessment, industrial ecology, climate change

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Authors: Haroon Khan, Chul Min Kim, Sung Yeol Kim, Sanket Goel, Prabhat K. Dwivedi, Ashutosh Sharma, Gyu Man Kim

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Enzymatic biofuel cells (EBFCs) have drawn the attention of researchers due to its demanding application in medical implants. In EBFCs, electricity is produced with the help of redox enzymes. In this study, we report the fabrication of membraneless EBFC with new design of electrodes to overcome microchannel related limitations. The device consists of double layer of electrodes on both sides of Y-shaped microchannel to reduce the effect of oxygen depletion layer and diffusion of fuel and oxidant at the end of microchannel. Moreover, the length of microchannel was reduced by half keeping the same area of multiwalled carbon nanotubes (MWCNT) electrodes. Polydimethylsiloxane (PDMS) stencils were used to pattern MWCNT electrodes on etched Indium Tin Oxide (ITO) glass. PDMS casting was used to fabricate microchannel of the device. Both anode and cathode were modified with glucose oxidase and laccase. Furthermore, these enzymes were covalently bound to carboxyl MWCNTs with the help of EDC/NHS. Glucose used as fuel was oxidized by glucose oxidase at anode while oxygen was reduced to water at the cathode side. The resulted devices were investigated with the help of polarization curves obtained from Chronopotentiometry technique by using potentiostat. From results, we conclude that the performance of double layer EBFC is improved 15 % as compared to single layer EBFC delivering maximum power density of 71.25 µW cm-2 at a cell potential of 0.3 V and current density of 250 µA cm-2 at micro channel height of 450-µm and flow rate of 25 ml hr-1. However, the new device was stable only for three days after which its power output was rapidly dropped by 75 %. This work demonstrates that the power output of membraneless EBFC is improved comparatively, but still efforts will be needed to make the device stable over long period of time.

Keywords: EBFC, glucose, MWCNT, microfluidic

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Authors: Sumedha Weerasekara, Morgan Miles, Mark Morrison, Branka Krivokapic-Skoko

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This paper is aimed at exploring the interrelationships among entrepreneurial ecosystem factors and entrepreneurial cognition in regional and metropolitan ecosystems. Entrepreneurial ecosystem factors examined include: culture, infrastructure, access to finance, informal networks, support services, access to universities, and the depth and breadth of the talent pool. Using a multivariate approach we explore the impact of these ecosystem factors or elements on entrepreneurial cognition. In doing so, the existing body of knowledge from the literature on entrepreneurial ecosystem and cognition have been blended to explore the relationship between entrepreneurial ecosystem factors and cognition in a way not hitherto investigated. The concept of the entrepreneurial ecosystem has received increased attention as governments, universities and communities have started to recognize the potential of integrated policies, structures, programs and processes that foster entrepreneurship activities by supporting innovation, productivity and employment growth. The notion of entrepreneurial ecosystems has evolved and grown with the advancement of theoretical research and empirical studies. Importance of incorporating external factors like culture, political environment, and the economic environment within a single framework will enhance the capacity of examining the whole systems functionality to better understand the interaction of the entrepreneurial actors and factors within a single framework. The literature on clusters underplays the role of entrepreneurs and entrepreneurial management in creating and co-creating organizations, markets, and supporting ecosystems. Entrepreneurs are only one actor following a limited set of roles and dependent upon many other factors to thrive. As a consequence, entrepreneurs and relevant authorities should be aware of the other actors and factors with which they engage and rely, and make strategic choices to achieve both self and also collective objectives. The study uses stratified random sampling method to collect survey data from 12 different regions in regional and metropolitan regions of NSW, Australia. A questionnaire was administered online among 512 Small and medium enterprise owners operating their business in selected 12 regions in NSW, Australia. Data were analyzed using descriptive analyzing techniques and partial least squares - structural equation modeling. The findings show that even though there is a significant relationship between each and every entrepreneurial ecosystem factors, there is a weak relationship between most entrepreneurial ecosystem factors and entrepreneurial cognition. In the metropolitan context, the availability of finance and informal networks have the largest impact on entrepreneurial cognition while culture, infrastructure, and support services having the smallest impact and the talent pool and universities having a moderate impact on entrepreneurial cognition. Interestingly, in a regional context, culture, availability of finance, and the talent pool have the highest impact on entrepreneurial cognition, while informal networks having the smallest impact and the remaining factors – infrastructure, universities, and support services have a moderate impact on entrepreneurial cognition. These findings suggest the need for a location-specific strategy for supporting the development of entrepreneurial cognition.

Keywords: academic achievement, colour response card, feedback

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Authors: S. K. Ashiquer Rahman

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A cutting-edge online knowledge mediation system called "ePLANETe" provides a framework for building knowledge, tools and methods for all education, research and sustainable practices and elsewhere, as well as the deliberative assessment support of sustainability, biodiversity, and stakeholder involvement issues of the territorial development sector, e.g., agriculture.The purpose is to present, as sectorial and institutional perception, the 'ePLANETe' concept and functionalities as an experimental online platform for contributing the sustainability assessment, biodiversity, and stakeholder involvement. In the upshot, the concept of 'ePLANETe'isan investigation of the challenges of "online things, technology and application". The new digital technologies are exploited to facilitate collaborative technology and application to territorial development issues, e.g., agriculture. In order to investigate the dealing capacity (Qualitative and Quantitative) of sustainability, biodiversity, and stakeholder involvement of the agriculture sector through the stakeholder-based integrated assessment "Deliberation Support Tools (DST) and INTEGRAAL method" of collective resources. Specifically, this paper focuses on integrating system methodologies with deliberation tools for collective assessment and decision-making in implementing regional plans of agriculture. The aim of this report is to identify effective knowledge and tools and to enable deliberation methodologies regarding practices on the sustainability of agriculture and biodiversity issues, societal responsibilities, and regional planning that will create the scope for qualitative and quantitative assessments of sustainability as a new landmark of the agriculture sector.

Keywords: sustainability, biodiversity, stakeholder, dst, integraal

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Authors: Vallejo Michael, Acuña Edgar, Roa Juan David, Peñuela Rosa, Parra Alejandra, Casallas Daniela, Rodriguez Sheyla

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Congenital Zika Virus Syndrome is an entity composed by a variety of birth defects presented in newborns that have been exposed to the Zika Virus during pregnancy. The syndrome characteristic features are severe microcephaly, cerebral tissue abnormalities, ophthalmological abnormalities such as uveitis and chorioretinitis, arthrogryposis, clubfoot deformity and muscular tone abnormalities. The confirmatory test is the Reverse transcription polymerase chain reaction (RT-PCR) associated to the physical findings. Here we present the case of a newborn with microcephaly whose mother presented a confirmed Zika Virus infection during the third trimester of pregnancy, despite of the evident findings and the history of Zika infection the RT-PCR in amniotic and cerebrospinal fluid of the newborn was negative. RT-PCR has demonstrated a low sensibility in samples with low viral loads, reason why, we propose a clinical diagnosis in patients with clinical history of Zika Virus infection during pregnancy accompanied by evident clinical manifestations of the child.

Keywords: congenital, Zika virus, microcephaly, reverse transcriptase polymerase chain reaction

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