Search results for: cooperative spectrum sensing
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2778

Search results for: cooperative spectrum sensing

768 Reconstruction Spectral Reflectance Cube Based on Artificial Neural Network for Multispectral Imaging System

Authors: Iwan Cony Setiadi, Aulia M. T. Nasution

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The multispectral imaging (MSI) technique has been used for skin analysis, especially for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel. For ergonomic purpose, our multispectral imaging system is decomposed in two parts: a light source compartment based on LED with 11 different wavelenghts and a monochromatic 8-Bit CCD camera with C-Mount Objective Lens. The software based on GUI MATLAB to control the system was also developed. Our system provides 11 monoband images and is coupled with a software reconstructing hyperspectral cubes from these multispectral images. In this paper, we proposed a new method to build a hyperspectral reflectance cube based on artificial neural network algorithm. After preliminary corrections, a neural network is trained using the 32 natural color from X-Rite Color Checker Passport. The learning procedure involves acquisition, by a spectrophotometer. This neural network is then used to retrieve a megapixel multispectral cube between 380 and 880 nm with a 5 nm resolution from a low-spectral-resolution multispectral acquisition. As hyperspectral cubes contain spectra for each pixel; comparison should be done between the theoretical values from the spectrophotometer and the reconstructed spectrum. To evaluate the performance of reconstruction, we used the Goodness of Fit Coefficient (GFC) and Root Mean Squared Error (RMSE). To validate reconstruction, the set of 8 colour patches reconstructed by our MSI system and the one recorded by the spectrophotometer were compared. The average GFC was 0.9990 (standard deviation = 0.0010) and the average RMSE is 0.2167 (standard deviation = 0.064).

Keywords: multispectral imaging, reflectance cube, spectral reconstruction, artificial neural network

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767 A Call for Justice and a New Economic Paradigm: Analyzing Counterhegemonic Discourses for Indigenous Peoples' Rights and Environmental Protection in Philippine Alternative Media

Authors: B. F. Espiritu

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This paper examines the resistance of the Lumad people, the indigenous peoples in Mindanao, Southern Philippines, and of environmental and human rights activists to the Philippine government's neoliberal policies and their call for justice and a new economic paradigm that will uphold peoples' rights and environmental protection in two alternative media online sites. The study contributes to the body of knowledge on indigenous resistance to neoliberal globalization and the quest for a new economic paradigm that upholds social justice for the marginalized in society, empathy and compassion for those who depend on the land for their survival, and environmental sustainability. The study analyzes the discourses in selected news articles from Davao Today and Kalikasan (translated to English as 'Nature') People's Network for the Environment’s statements and advocacy articles for the Lumad and the environment from 2018 to February 2020. The study reveals that the alternative media news articles and the advocacy articles contain statements that expose the oppression and violation of human rights of the Lumad people, farmers, government environmental workers, and environmental activists as shown in their killings, illegal arrest and detention, displacement of the indigenous peoples, destruction of their schools by the military and paramilitary groups, and environmental plunder and destruction with the government's permit for the entry and operation of extractive and agribusiness industries in the Lumad ancestral lands. Anchored on Christian Fuch's theory of alternative media as critical media and Bert Cammaerts' theorization of alternative media as counterhegemonic media that are part of civil society and form a third voice between state media and commercial media, the study reveals the counterhegemonic discourses of the news and advocacy articles that oppose the dominant economic system of neoliberalism which oppresses the people who depend on the land for their survival. Furthermore, the news and advocacy articles seek to advance social struggles that transform society towards the realization of cooperative potentials or a new economic paradigm that upholds economic democracy, where the local people, including the indigenous people, are economically empowered their environment and protected towards the realization of self-sustaining communities. The study highlights the call for justice, empathy, and compassion for both the people and the environment and the need for a new economic paradigm wherein indigenous peoples and local communities are empowered towards becoming self-sustaining communities in a sustainable environment.

Keywords: alternative media, environmental sustainability, human rights, indigenous resistance

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766 Laser-Hole Boring into Overdense Targets: A Detailed Study on Laser and Target Properties

Authors: Florian Wagner, Christoph Schmidt, Vincent Bagnoud

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Understanding the interaction of ultra-intense laser pulses with overcritical targets is of major interest for many applications such as laser-driven ion acceleration, fast ignition in the frame of inertial confinement fusion or high harmonic generation and the creation of attosecond pulses. One particular aspect of this interaction is the shift of the critical surface, where the laser pulse is stopped and the absorption is at maximum, due to the radiation pressure induced by the laser pulse, also referred to as laser hole boring. We investigate laser-hole boring experimentally by measuring the backscattered spectrum which is doppler-broadened because of the movement of the reflecting surface. Using the high-power, high-energy laser system PHELIX in Darmstadt, we gathered an extensive set of data for different laser intensities ranging from 10^18 W/cm2 to 10^21 W/cm2, two different levels of the nanosecond temporal contrast (10^6 vs. 10^11), elliptical and linear polarization and varying target configurations. In this contribution we discuss how the maximum velocity of the critical surface depends on these parameters. In particular we show that by increasing the temporal contrast the maximum hole boring velocity is decreased by more than a factor of three. Our experimental findings are backed by a basic analytical model based on momentum and mass conservation as well as particle in cell simulations. These results are of particular importance for fast ignition since they contribute to a better understanding of the transport of the ignitor pulse into the overdense region.

Keywords: laser-hole boring, interaction of ultra-intense lasers with overcritical targets, fast ignition, relativistic laser motter interaction

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765 Non Linear Stability of Non Newtonian Thin Liquid Film Flowing down an Incline

Authors: Lamia Bourdache, Amar Djema

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The effect of non-Newtonian property (power law index n) on traveling waves of thin layer of power law fluid flowing over an inclined plane is investigated. For this, a simplified second-order two-equation model (SM) is used. The complete model is second-order four-equation (CM). It is derived by combining the weighted residual integral method and the lubrication theory. This is due to the fact that at the beginning of the instability waves, a very small number of waves is observed. Using a suitable set of test functions, second order terms are eliminated from the calculus so that the model is still accurate to the second order approximation. Linear, spatial, and temporal stabilities are studied. For travelling waves, a particular type of wave form that is steady in a moving frame, i.e., that travels at a constant celerity without changing its shape is studied. This type of solutions which are characterized by their celerity exists under suitable conditions, when the widening due to dispersion is balanced exactly by the narrowing effect due to the nonlinearity. Changing the parameter of celerity in some range allows exploring the entire spectrum of asymptotic behavior of these traveling waves. The (SM) model is converted into a three dimensional dynamical system. The result is that the model exhibits bifurcation scenarios such as heteroclinic, homoclinic, Hopf, and period-doubling bifurcations for different values of the power law index n. The influence of the non-Newtonian parameter on the nonlinear development of these travelling waves is discussed. It is found at the end that the qualitative characters of bifurcation scenarios are insensitive to the variation of the power law index.

Keywords: inclined plane, nonlinear stability, non-Newtonian, thin film

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764 A Spatial Hypergraph Based Semi-Supervised Band Selection Method for Hyperspectral Imagery Semantic Interpretation

Authors: Akrem Sellami, Imed Riadh Farah

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Hyperspectral imagery (HSI) typically provides a wealth of information captured in a wide range of the electromagnetic spectrum for each pixel in the image. Hence, a pixel in HSI is a high-dimensional vector of intensities with a large spectral range and a high spectral resolution. Therefore, the semantic interpretation is a challenging task of HSI analysis. We focused in this paper on object classification as HSI semantic interpretation. However, HSI classification still faces some issues, among which are the following: The spatial variability of spectral signatures, the high number of spectral bands, and the high cost of true sample labeling. Therefore, the high number of spectral bands and the low number of training samples pose the problem of the curse of dimensionality. In order to resolve this problem, we propose to introduce the process of dimensionality reduction trying to improve the classification of HSI. The presented approach is a semi-supervised band selection method based on spatial hypergraph embedding model to represent higher order relationships with different weights of the spatial neighbors corresponding to the centroid of pixel. This semi-supervised band selection has been developed to select useful bands for object classification. The presented approach is evaluated on AVIRIS and ROSIS HSIs and compared to other dimensionality reduction methods. The experimental results demonstrate the efficacy of our approach compared to many existing dimensionality reduction methods for HSI classification.

Keywords: dimensionality reduction, hyperspectral image, semantic interpretation, spatial hypergraph

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763 Interrogating Economic Growth and Development in Nigeria: The Challenges

Authors: Enojo Kennie Enojo

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The paper focuses on the contradictions of economic growth and development in Nigeria with specific reference to the plethora issues and challenges associated with the sordid situation. The broad objective is to investigate the major causes of agitation for restructuring the entire political spectrum that promote and guarantee economic growth and development with empirical intellectual standpoint. The specific aim is to surgically examine the organic linkage between weaker institutions, lack of vibrant civil society, poor governance and the agitation for restructuring. The paper adopts the secondary source of data collection as its methodological strategy. Our findings reveals that most urban and rural dwellers where goods and services are either extracted, produced, or manufactured lack infrastructural facilities, preventing economic growth and development, which has been the consequence of poverty, inequality and unemployment. There is equally the issue of disconnection of the political class from the electorate, this is evident in lack of political power base not located in the society but rather with either the elites or godfathers this and many factors are responsible for flawed electoral system from 1999 to 2023 general elections. These egregious factors and others have resulted in the subscription of religion and ethnicity thereby the devaluation of national norms, identities and values. We adopt the combination of structural-functional approach, relative deprivation; rising expectation, frustration and aggression model to enable us critically interrogate these contradictions as subterfuge with both the centrifugal and centripetal forces constantly in fatality. We recommend among others that, there should be development across the federating units without prejudice.

Keywords: restructuring, infrastructure, economic development, governance

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762 Transcriptomic Analyses of Kappaphycus alvarezii under Different Wavelengths of Light

Authors: Vun Yee Thien, Kenneth Francis Rodrigues, Clemente Michael Vui Ling Wong, Wilson Thau Lym Yong

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Transcriptomes associated with the process of photosynthesis have offered insights into the mechanism of gene regulation in terrestrial plants; however, limited information is available as far as macroalgae are concerned. This investigation aims to decipher the underlying mechanisms associated with photosynthesis in the red alga, Kappaphycus alvarezii, by performing a differential expression analysis on a de novo assembled transcriptomes. Comparative analysis of gene expression was designed to examine the alteration of light qualities and its effect on physiological mechanisms in the red alga. High-throughput paired-end RNA-sequencing was applied to profile the transcriptome of K. alvarezii irradiated with different wavelengths of light (blue 492-455 nm, green 577-492 nm and red 780-622 nm) as compared to the full light spectrum, resulted in more than 60 million reads individually and assembled using Trinity and SOAPdenovo-Trans. The transcripts were annotated in the NCBI non-redundant (nr) protein, SwissProt, KEGG and COG databases with a cutoff E-value of 1e-5 and nearly 30% of transcripts were assigned to functional annotation by Blast searches. Differential expression analysis was performed using edgeR. The DEGs were designated to six categories: BL (blue light) regulated, GL (green light) regulated, RL (red light) regulated, BL or GL regulated, BL or RL regulated, GL or RL regulated, and either BL, GL or RL regulated. These DEGs were mapped to terms in KEGG database and compared with the whole transcriptome background to search for genes that regulated by light quality. The outcomes of this study will enhance our understanding of molecular mechanisms underlying light-induced responses in red algae.

Keywords: de novo transcriptome sequencing, differential gene expression, Kappaphycus alvareziired, red alga

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761 Rapid Green Synthesis of Silver Nanoparticles Using Solanum Nigrum Leaves Extract with Antimicrobial and Anticancer Properties

Authors: Anushaa A.

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In this work, silver nanoparticles (AgNP) were manufactured directly without harmful chemicals utilising methanol extract (SNLME) Solanum nigrume leaves. We are using nigrum leaf extract from Solanum, which converts silver nitrate to silver ions, for synthesization purposes. An examination of the AgNP produced was performed using ultraviolet (UV-VIS) spectroscopy, infrared spectroscopy (FTIR) transformed from Fourier and scanning electrons (SEM). Biological activity was also tested. UV-VIS has proven that biosynthesized AgNP exists (420-450 nm). The FTIR spectrum has been utilised to confirm the presence of different functional groups within the biomolecules, which are a nanoparticular capping agent and the spectroscopic and crystal nature of AgNP. The viability of the silver nanoparticles was evaluated using zeta potential calculations. Negative zeta potential of -33.4 mV demonstrated the stability of silver-nanoparticles. The morphology of AgNP was examined using a scanning electron microscope. Greenly generated AgNP showed significant anti-Staphylococcus aureus, Candida, and Escherichia coli action. The green AgNP demonstration indicated that the IC50 for the human teratocarcinoma cell line was 29.24 μg/ml during 24 hours of therapy (PA1 Ovarian cell line). The dose-dependent effects were reported in both antibacterial and cytotoxicity assays and as an effective agent. Finally, the findings of this research showed that silver nanoparticles generated might serve as a viable therapeutic agent to combat microorganisms killing and curing cancer.

Keywords: antimicrobial activity, PA1 ovarian cancer cell line, silver nanoparticles, Solanum nigrum

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760 Reasons for Adhesion of Membership: A Case Study of Brazilian Soccer Team

Authors: Alexandre Olkoski, Marcelo Curth

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Football in Brazil is considered a passion, being the most popular sport in the country, both by the consumer public and by the means of communication that divulge it individually, when compared with other sports modalities. In the last two decades, the soccer teams have given greater importance to the management, since they understood that the same should be managed as a company, but with peculiarities related to the business. In this sense, Brazilian soccer clubs started to make bigger investments for the adhesion of fans in their social frames, allowing a greater need of understanding about the profile of this group of fans/clients. Thus, this work aims to understand the reasons that cause the fans to join the club and identify variables present in the process of intention to join the club. For that, a qualitative exploratory research was conducted, in which thirty-one membership of a soccer club from southern Brazil were interviewed. Based on the interviews, five categories were classified as emotional aspects (passion and love), cognitive aspects (easy access to the stadium and promotional values in tickets), external influences (family and friends), situational aspects (club moment) and aspects related to the event (engagement by modality). As results found in the analysis, it can be highlighted that the motivation of the majority of the respondents to become a member of the analyzed club, is related to the emotional aspects, such as passion and love. Thus, it is perceived that sport, in the case of soccer, generates in the involved ones (fans and leaders) different manifestations, suggesting that the management of this type of business has great complexity and should not be observed only by the spectrum of the club like a business.

Keywords: consumer behavior, marketing, membership, soccer

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759 Electronic Spectral Function of Double Quantum Dots–Superconductors Nanoscopic Junction

Authors: Rajendra Kumar

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We study the Electronic spectral density of a double coupled quantum dots sandwich between superconducting leads, where one of the superconducting leads (QD1) are connected with left superconductor lead and (QD1) also connected right superconductor lead. (QD1) and (QD2) are coupling to each other. The electronic spectral density through a quantum dots between superconducting leads having s-wave symmetry of the superconducting order parameter. Such junction is called superconducting –quantum dot (S-QD-S) junction. For this purpose, we have considered a renormalized Anderson model that includes the double coupled of the superconducting leads with the quantum dots level and an attractive BCS-type effective interaction in superconducting leads. We employed the Green’s function technique to obtain superconducting order parameter with the BCS framework and Ambegaoker-Baratoff formalism to analyze the electronic spectral density through such (S-QD-S) junction. It has been pointed out that electronic spectral density through such a junction is dominated by the attractive the paring interaction in the leads, energy of the level on the dot with respect to Fermi energy and also on the coupling parameter of the two in an essential way. On the basis of numerical analysis we have compared the theoretical results of electronic spectral density with the recent transport existing theoretical analysis. QDs is the charging energy that may give rise to effects based on the interplay of Coulomb repulsion and superconducting correlations. It is, therefore, an interesting question to ask how the discrete level spectrum and the charging energy affect the DC and AC Josephson transport between two superconductors coupled via a QD. In the absence of a bias voltage, a finite DC current can be sustained in such an S-QD-S by the DC Josephson effect.

Keywords: quantum dots, S-QD-S junction, BCS superconductors, Anderson model

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758 Antibacterial Activity of Methanol Extract of Punica Granatum Linn. (Punnicaceae) Fruit Peel Against Selected Bacterial Species

Authors: Afzan Mahmad, Santibuana Abd Rahman, Gouri Kumar Dash, Mohd. Syafiq Bin Abdullah

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Antibacterial activity of the methanol extract of fruit peel of Punica granatum Linn (Family: Punicaceae) was evaluated against two Gram positive and two Gram negative bacteria. The Gram positive bacteria included Staphylococcus aureus, Streptococcus pneumoniae and the Gram negative organisms included Escherichia coli and Pseudomonas aeruginosa respectively. The culture media used for antibacterial assay was Mueller Hinton agar for the growth of S. aureus, E. coli, and P. aeruginosa. The media used for the growth of S. pneumoniae was Mueller Hinton blood agar. The antibacterial assay was performed through Disc diffusion technique. The methanol extract was tested at three different concentrations (50, 100 and 200 mg/ml). Standard antibiotic discs containing vancomycin (30 μg) for S. pneumoniae, penicillin (10 units) for S. aureus, ceftriaxone (30 μg) for E. coli and ciprofloxacin (5 μg) for P. aeruginosa were used for the activity comparison. The results of the study revealed that the extract possesses antibacterial activity against S. aureus, S. pneumoniae and P. aeruginosa at all tested concentrations. The maximum zone of inhibition of 19 mm of the extract at 200 mg/ml was observed against S. pneumoniae. However, no zone of inhibition was observed against E. coli at the tested concentrations of the extract. Based on the results obtained in this study, it may be concluded that the fruit peel of P. granatum possess broad spectrum of antibacterial activity against a number bacteria.

Keywords: Punica granatum Linn., methanol extract, antibacterial, zone of inhibition

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757 Utility of Geospatial Techniques in Delineating Groundwater-Dependent Ecosystems in Arid Environments

Authors: Mangana B. Rampheri, Timothy Dube, Farai Dondofema, Tatenda Dalu

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Identifying and delineating groundwater-dependent ecosystems (GDEs) is critical to the well understanding of the GDEs spatial distribution as well as groundwater allocation. However, this information is inadequately understood due to limited available data for the most area of concerns. Thus, this study aims to address this gap using remotely sensed, analytical hierarchy process (AHP) and in-situ data to identify and delineate GDEs in Khakea-Bray Transboundary Aquifer. Our study developed GDEs index, which integrates seven explanatory variables, namely, Normalized Difference Vegetation Index (NDVI), Modified Normalized Difference Water Index (MNDWI), Land-use and landcover (LULC), slope, Topographic Wetness Index (TWI), flow accumulation and curvature. The GDEs map was delineated using the weighted overlay tool in ArcGIS environments. The map was spatially classified into two classes, namely, GDEs and Non-GDEs. The results showed that only 1,34 % (721,91 km2) of the area is characterised by GDEs. Finally, groundwater level (GWL) data was used for validation through correlation analysis. Our results indicated that: 1) GDEs are concentrated at the northern, central, and south-western part of our study area, and 2) the validation results showed that GDEs classes do not overlap with GWL located in the 22 boreholes found in the given area. However, the results show a possible delineation of GDEs in the study area using remote sensing and GIS techniques along with AHP. The results of this study further contribute to identifying and delineating priority areas where appropriate water conservation programs, as well as strategies for sustainable groundwater development, can be implemented.

Keywords: analytical hierarchy process (AHP), explanatory variables, groundwater-dependent ecosystems (GDEs), khakea-bray transboundary aquifer, sentinel-2

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756 Enzymatic Hydrolysis of Sugar Cane Bagasse Using Recombinant Hemicellulases

Authors: Lorena C. Cintra, Izadora M. De Oliveira, Amanda G. Fernandes, Francieli Colussi, Rosália S. A. Jesuíno, Fabrícia P. Faria, Cirano J. Ulhoa

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Xylan is the main component of hemicellulose and for its complete degradation is required cooperative action of a system consisting of several enzymes including endo-xylanases (XYN), β-xylosidases (XYL) and α-L-arabinofuranosidases (ABF). The recombinant hemicellulolytic enzymes an endoxylanase (HXYN2), β-xylosidase (HXYLA), and an α-L-arabinofuranosidase (ABF3) were used in hydrolysis tests. These three enzymes are produced by filamentous fungi and were expressed heterologously and produced in Pichia pastoris previously. The aim of this work was to evaluate the effect of recombinant hemicellulolytic enzymes on the enzymatic hydrolysis of sugarcane bagasse (SCB). The interaction between the three recombinant enzymes during SCB pre-treated by steam explosion hydrolysis was performed with different concentrations of HXYN2, HXYLA and ABF3 in different ratios in according to a central composite rotational design (CCRD) 23, including six axial points and six central points, totaling 20 assays. The influence of the factors was assessed by analyzing the main effects and interaction between the factors, calculated using Statistica 8.0 software (StatSoft Inc. Tulsa, OK, USA). The Pareto chart was constructed with this software and showed the values of the Student’s t test for each recombinant enzyme. It was considered as response variable the quantification of reducing sugars by DNS (mg/mL). The Pareto chart showed that the recombinant enzyme ABF3 exerted more significant effect during SCB hydrolysis, with higher concentrations and with the lowest concentration of this enzyme. It was performed analysis of variance according to Fisher method (ANOVA). In ANOVA for the release of reducing sugars (mg/ml) as the variable response, the concentration of ABF3 showed significance during hydrolysis SCB. The result obtained by ANOVA, is in accordance with those presented in the analysis method based on the statistical Student's t (Pareto chart). The degradation of the central chain of xylan by HXYN2 and HXYLA was more strongly influenced by ABF3 action. A model was obtained, and it describes the performance of the interaction of all three enzymes for the release of reducing sugars, and can be used to better explain the results of the statistical analysis. The formulation capable of releasing the higher levels of reducing sugars had the following concentrations: HXYN2 with 600 U/g of substrate, HXYLA with 11.5 U.g-1 and ABF3 with 0.32 U.g-1. In conclusion, the recombinant enzyme that has a more significant effect during SCB hydrolysis was ABF3. It is noteworthy that the xylan present in the SCB is arabinoglucoronoxylan, due to this fact debranching enzymes are important to allow access of enzymes that act on the central chain.

Keywords: experimental design, hydrolysis, recombinant enzymes, sugar cane bagasse

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755 Recession Rate of Gangotri and Its Tributary Glacier, Garhwal Himalaya, India through Kinematic GPS Survey and Satellite Data

Authors: Harish Bisht, Bahadur Singh Kotlia, Kireet Kumar

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In order to reconstruct past retreating rates, total area loss, volume change and shift in snout position were measured through multi-temporal satellite data from 1989 to 2016 and kinematic GPS survey from 2015 to 2016. The results obtained from satellite data indicate that in the last 27 years, Chaturangi glacier snout has retreated 1172.57 ± 38.3 m (average 45.07 ± 4.31 m/year) with a total area and volume loss of 0.626 ± 0.001 sq. Km and 0.139 Km³, respectively. The field measurements through differential global positioning system survey revealed that the annual retreating rate was 22.84 ± 0.05 m/year. The large variations in results derived from both the methods are probably because of higher difference in their accuracy. Snout monitoring of the Gangotri glacier during the ablation season (May to September) in the years 2005 and 2015 reveals that the retreating rate has been comparatively more declined than that shown by the earlier studies. The GPS dataset shows that the average recession rate is 10.26 ± 0.05 m/year. In order to determine the possible causes of decreased retreating rate, a relationship between debris thickness and melt rate was also established by using ablation stakes. The present study concludes that remote sensing method is suitable for large area and long term study, while kinematic GPS is more appropriate for the annual monitoring of retreating rate of glacier snout. The present study also emphasizes on mapping of all the tributary glaciers in order to assess the overall changes in the main glacier system and its health.

Keywords: Chaturangi glacier, Gangotri glacier, glacier snout, kinematic global positioning system, retreat rate

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754 Eco-Friendly Control of Bacterial Speck on Solanum lycopersicum by Azadirachta indica Extract

Authors: Navodit Goel, Prabir K. Paul

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Tomato (Solanum lycopersicum) is attacked by Pseudomonas syringae pv. tomato causing speck lesions on the leaves leading to severe economic casualty. In the present study, aqueous fruit extracts of Azadirachta indica (neem) were sprayed on a single node of tomato plants grown under controlled contamination-free conditions. The treatment of plants was performed with neem fruit extract either alone or along with the pathogen. The parameters of observation were activities of polyphenol oxidase (PPO) and lysozyme, and isoform analysis of PPO; both at the treated leaves as well as untreated leaves away from the site of extract application. Polyphenol oxidase initiates phenylpropanoid pathway resulting in the synthesis of quinines from cytoplasmic phenols and production of reactive oxygen species toxic to broad spectrum microbes. Lysozyme is responsible for the breakdown of bacterial cell wall. The results indicate the upregulation of PPO and lysozyme activities in both the treated and untreated leaves along with de novo expression of newer PPO isoenzymes (which were absent in control samples). The appearance of additional PPO isoenzymes in bioelicitor-treated plants indicates that either the isoenzymes were expressed after bioelicitor application or the already expressed but inactive isoenzymes were activated by it. Lysozyme activity was significantly increased in the plants when treated with the bioelicitor or the pathogen alone. However, no new isoenzymes of lysozyme were expressed upon application of the extract. Induction of resistance by neem fruit extract could be a potent weapon in eco-friendly plant protection strategies.

Keywords: Azadirachta indica, lysozyme, polyphenol oxidase, Solanum lycopersicum

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753 Analysis on Solar Panel Performance and PV-Inverter Configuration for Tropical Region

Authors: Eko Adhi Setiawan, Duli Asih Siregar, Aiman Setiawan

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Solar energy is abundant in nature, particularly in the tropics which have peak sun hour that can reach 8 hours per day. In the fabrication process, Photovoltaic’s (PV) performance are tested in standard test conditions (STC). It specifies a module temperature of 25°C, an irradiance of 1000 W/ m² with an air mass 1.5 (AM1.5) spectrum and zero wind speed. Thus, the results of the performance testing of PV at STC conditions cannot fully represent the performance of PV in the tropics. For example Indonesia, which has a temperature of 20-40°C. In this paper, the effect of temperature on the choice of the 5 kW AC inverter topology on the PV system such as the Central Inverter, String Inverter and AC-Module specifically for the tropics will be discussed. The proper inverter topology can be determined by analysis of the effect of temperature and irradiation on the PV panel. The effect of temperature and irradiation will be represented in the characteristics of I-V and P-V curves. PV’s characteristics on high temperature would be analyzed using Solar panel modeling through MATLAB Simulink based on mathematical equations that form Solar panel’s characteristic curve. Based on PV simulation, it is known then that temperature coefficients of short circuit current (ISC), open circuit voltage (VOC), and maximum output power (PMAX) consecutively as high as 0.56%/oC, -0.31%/oC and -0.4%/oC. Those coefficients can be used to calculate PV’s electrical parameters such as ISC, VOC, and PMAX in certain earth’s surface’s certain point. Then, from the parameters, the utility of the 5 kW AC inverter system can be determined. As the result, for tropical area, string inverter topology has the highest utility rates with 98, 80 %. On the other hand, central inverter and AC-Module Topology has utility rates of 92.69 % and 87.7 % eventually.

Keywords: Photovoltaic, PV-Inverter Configuration, PV Modeling, Solar Panel Characteristics.

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752 Normal Coordinate Analysis, Molecular Structure, Vibrational, Electronic Spectra, and NMR Investigation of 4-Amino-3-Phenyl-1H-1,2,4-Triazole-5(4H)-Thione by Ab Initio HF and DFT Method

Authors: Khaled Bahgat

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In the present work, the characterization of 4-Amino-3-phenyl-1H-1,2,4-triazole-5(4H)-thione (APTT) molecule was carried out by quantum chemical method and vibrational spectral techniques. The FT-IR (4000–400 cm_1) and FT-Raman (4000–100 cm_1) spectra of APTT were recorded in solid phase. The UV–Vis absorption spectrum of the APTT was recorded in the range of 200–400 nm. The molecular geometry, harmonic vibrational frequencies and bonding features of APTT in the ground state have been calculated by HF and DFT methods using 6-311++G(d,p) basis set. The complete vibrational frequency assignments were made by normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMF). The molecular stability and bond strength were investigated by applying the natural bond orbital analysis (NBO) and natural localized molecular orbital (NLMO) analysis. The electronic properties, such as excitation energies, absorption wavelength, HOMO and LUMO energies were performed by time depended DFT (TD-DFT) approach. The 1H and 13C nuclear magnetic resonance chemical shift of the molecule were calculated using the gauge-including atomic orbital (GIAO) method and compared with experimental results. Finally, the calculation results were analyzed to simulate infrared, FT-Raman and UV spectra of the title compound which shows better agreement with observed spectra.

Keywords: 4-amino-3-phenyl-1H-1, 2, 4-triazole-5(4H)-thione, vibrational assignments, normal coordinate analysis, quantum mechanical calculations

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751 Crab Shell Waste Chitosan-Based Thin Film for Acoustic Sensor Applications

Authors: Maydariana Ayuningtyas, Bambang Riyanto, Akhiruddin Maddu

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Industrial waste of crustacean shells, such as shrimp and crab, has been considered as one of the major issues contributing to environmental pollution. The waste processing mechanisms to form new, practical substances with added value have been developed. Chitosan, a derived matter from chitin, which is obtained from crab and shrimp shells, performs prodigiously in broad range applications. A chitosan composite-based diaphragm is a new inspiration in fiber optic acoustic sensor advancement. Elastic modulus, dynamic response, and sensitivity to acoustic wave of chitosan-based composite film contribute great potentials of organic-based sound-detecting material. The objective of this research was to develop chitosan diaphragm application in fiber optic microphone system. The formulation was conducted by blending 5% polyvinyl alcohol (PVA) solution with dissolved chitosan at 0%, 1% and 2% in 1:1 ratio, respectively. Composite diaphragms were characterized for the morphological and mechanical properties to predict the desired acoustic sensor sensitivity. The composite with 2% chitosan indicated optimum performance with 242.55 µm thickness, 67.9% relative humidity, and 29-76% light transmittance. The Young’s modulus of 2%-chitosan composite material was 4.89×104 N/m2, which generated the voltage amplitude of 0.013V and performed sensitivity of 3.28 mV/Pa at 1 kHz. Based on the results above, chitosan from crustacean shell waste can be considered as a viable alternative material for fiber optic acoustic sensor sensing pad development. Further, the research in chitosan utilisation is proposed as novel optical microphone development in anthropogenic noise controlling effort for environmental and biodiversity conservation.

Keywords: acoustic sensor, chitosan, composite, crab shell, diaphragm, waste utilisation

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750 Sudden Death and Chronic Disseminated Intravascular Coagulation (DIC): Two Case Reports

Authors: Saker Lilia, Youcef Mellouki, Lakhdar Sellami, Yacine Zerairia, Abdelhaid Zetili, Fatma Guahria, Fateh Kaious, Nesrine Belkhodja, Abdelhamid Mira

Abstract:

Background: Sudden death is regarded as a suspicious demise necessitating autopsy, as stipulated by legal authorities. Chronic disseminated intravascular coagulation (DIC) is an acquired clinical and biological syndrome characterized by a severe and fatal prognosis, stemming from systemic, uncontrolled, diffuse coagulation activation. Irrespective of their origins, DIC is associated with a diverse spectrum of manifestations, encompassing minor biological coagulation alterations to profoundly severe conditions wherein hemorrhagic complications may take precedence. Simultaneously, microthrombi contribute to the development of multi-organ failures. Objective This study seeks to evaluate the role of autopsy in determining the causes of death. Materials and Methods: We present two instances of sudden death involving females who underwent autopsy at the Forensic Medicine Department of the University Hospital of Annaba, Algeria. These autopsies were performed at the request of the prosecutor, aiming to determine the causes of death and illuminate the exact circumstances surrounding it. Methods Utilized: Analysis of the initial information report; Findings from postmortem examinations; Histological assessments and toxicological analyses. Results: The presence of DIC was noted, affecting nearly all veins with distinct etiologies. Conclusion: For the establishment of a meaningful diagnosis: • Thorough understanding of the subject matter is imperative; • Precise alignment with medicolegal data is essential.

Keywords: chronic disseminated intravascular coagulation, sudden death, autopsy, causes of death

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749 Structure-Based Drug Design of Daptomycin, Antimicrobial lipopeptide

Authors: Satya Eswari Jujjavarapu, Swast Dhagat

Abstract:

Contagious diseases enact severe public health problems and have upsetting consequences. The cyclic lipopeptides explained by bacteria Bacillus, Paenibacillus, Pseudomonas, Streptomyces, Serratia, Propionibacterium and fungus Fusarium are very critical in confining the pathogens. As the degree of drug resistance upsurges in unparalleled manner, the perseverance of searching novel cyclic lipopeptides is being professed. The intense study has shown the implication of these bioactive compounds extending beyond antibacterial and antifungal. Lipopeptides, composed of single units of peptide and fatty acyl moiety, show broad spectrum antimicrobial effects. Among the surplus of cyclic lipopeptides, only few have materialized as strong antibiotics. For their functional vigor, polymyxin, daptomycin, surfactin, iturin and bacillomycin have been integrated in mainstream healthcare. In our work daptomycin has been a major part of antimicrobial resource since the past decade. Daptomycin, a cyclic lipopeptide consists of 13-member amino acid with a decanoyl side-chain. This structure of daptomycin confers it the mechanism of action through which it forms pore in the bacterial cell membrane resulting in the death of cell. Daptomycin is produced by Streptococccus roseoporus and acts against Streptococcus pneumonia (PSRP), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). The PDB structure and ligands of daptomycin are available online. The molecular docking studies of these ligands with the lipopeptides were performed and their docking score and glide energy were recorded.

Keywords: daptomycin, molecular docking, structure-based drug design, lipopeptide

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748 Neurosciences in Entrepreneurship: The Multitasking Case in Favor of Social Entrepreneurship Innovation

Authors: Berger Aida

Abstract:

Social entrepreneurship has emerged as an active area of practice and research within the last three decades and has called for a focus on Social Entrepreneurship innovation. Areas such as academics, practitioners , institutions or governments have placed Social Entrepreneurship on the priority list of reflexion and action. It has been accepted that Social entrepreneurship (SE) shares large similarities with its parent, Traditional Entrepreneurship (TE). SE has grown over the past ten years exploring entrepreneurial cognition and the analysis of the ways of thinking of entrepreneurs. The research community believes that value exists in grounding entrepreneurship in neuroscience and notes that SE, like Traditional Entrepreneurship, needs to undergo efforts in clarification, definition and differentiation. Moreover, gaps in SE research call for integrative multistage and multilevel framework for further research. The cognitive processes underpinning entrepreneurial action are similar for SE and TE even if Social Entrepreneurship orientation shows an increased empathy value. Theoretically, there is a need to develop sound models of how to process functions and how to work more effectively as entrepreneurs and research on efficiency improvement calls for the analysis of the most common practices in entrepreneurship. Multitasking has been recognized as a daily and unavoidable habit of entrepreneurs. Hence, we believe in the need of analyzing the multiple task phenomena as a methodology for skill acquisition. We will conduct our paper including Social Entrepreneurship within the wider spectrum of Traditional Entrepreneurship, for the purpose of simplifying the neuroscientific lecture of the entrepreneurial cognition. A question to be inquired is to know if there is a way of developing multitasking habits in order to improve entrepreneurial skills such as speed of information processing , creativity and adaptability . Nevertheless, the direct link between the neuroscientific approach to multitasking and entrepreneurship effectiveness is yet to be uncovered. That is why an extensive Literature Review on Multitasking is a propos.

Keywords: cognitive, entrepreneurial, empathy, multitasking

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747 Dynamic Corrosion Prevention through Magneto-Responsive Nanostructure with Controllable Hydrophobicity

Authors: Anne McCarthy, Anna Kim, Yin Song, Kyoo Jo, Donald Cropek, Sungmin Hong

Abstract:

Corrosion prevention remains an indispensable concern across a spectrum of industries, demanding inventive and adaptable methodologies to effectively tackle the ever-evolving obstacles presented by corrosive surroundings. This abstract introduces a pioneering approach to corrosion prevention that amalgamates the distinct attributes of magneto-responsive polymers with finely adjustable hydrophobicity inspired by the structure of cicada wings, effectively deterring bacterial proliferation and biofilm formation. The proposed strategy entails the creation of an innovative array of magneto-responsive nanostructures endowed with the capacity to dynamically modulate their hydrophobic characteristics. This dynamic control over hydrophobicity facilitates active repulsion of water and corrosive agents on demand. Additionally, the cyclic motion generated by magnetic activation prevents the biofilms formation and rejection. Thus, the synergistic interplay between magneto-active nanostructures and hydrophobicity manipulation establishes a versatile defensive mechanism against diverse corrosive agents. This study introduces a novel method for corrosion prevention, harnessing the advantages of magneto-active nanostructures and the precision of hydrophobicity adjustment, resulting in water-repellency, effective biofilm removal, and offering a promising solution to handle corrosion-related challenges. We believe that the combined effect will significantly contribute to extending asset lifespan, improving safety, and reducing maintenance costs in the face of corrosion threats.

Keywords: magneto-active material, nanoimprinting, corrosion prevention, hydrophobicity

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746 An Extensive Review Of Drought Indices

Authors: Shamsulhaq Amin

Abstract:

Drought can arise from several hydrometeorological phenomena that result in insufficient precipitation, soil moisture, and surface and groundwater flow, leading to conditions that are considerably drier than the usual water content or availability. Drought is often assessed using indices that are associated with meteorological, agricultural, and hydrological phenomena. In order to effectively handle drought disasters, it is essential to accurately determine the kind, intensity, and extent of the drought using drought characterization. This information is critical for managing the drought before, during, and after the rehabilitation process. Over a hundred drought assessments have been created in literature to evaluate drought disasters, encompassing a range of factors and variables. Some models utilise solely hydrometeorological drivers, while others employ remote sensing technology, and some incorporate a combination of both. Comprehending the entire notion of drought and taking into account drought indices along with their calculation processes are crucial for researchers in this discipline. Examining several drought metrics in different studies requires additional time and concentration. Hence, it is crucial to conduct a thorough examination of approaches used in drought indices in order to identify the most straightforward approach to avoid any discrepancies in numerous scientific studies. In case of practical application in real-world, categorizing indices relative to their usage in meteorological, agricultural, and hydrological phenomena might help researchers maximize their efficiency. Users have the ability to explore different indexes at the same time, allowing them to compare the convenience of use and evaluate the benefits and drawbacks of each. Moreover, certain indices exhibit interdependence, which enhances comprehension of their connections and assists in making informed decisions about their suitability in various scenarios. This study provides a comprehensive assessment of various drought indices, analysing their types and computation methodologies in a detailed and systematic manner.

Keywords: drought classification, drought severity, drought indices, agricultur, hydrological

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745 Optical Analysis of the Plasmon Resonances of Gold Nano-Ring

Authors: Mehrnaz Mostafavi

Abstract:

The current research aims to explore a method for creating nano-ring structures through chemical reduction. By employing a direct reduction process at a controlled, slow pace, and concurrently introducing specific reduction agents, the goal is to fabricate these unique nano-ring formations. The deliberate slow reduction of nanoparticles within this process helps prevent spatial hindrances caused by the reduction agents. The timing of the reduction of metal atoms, facilitated by these agents, emerges as a crucial factor influencing the creation of nano-ring structures. In investigation involves a chemical approach utilizing bovine serum albumin and human serum albumin as organic reducing agents to produce gold nano-rings. The controlled reduction of metal atoms at a slow pace and under specific pH conditions plays a pivotal role in the successful fabrication of these nanostructures. Optical spectroscopic analyses revealed distinctive plasmonic behavior in both visible and infrared spectra, owing to the collective movement of electrons along the inner and outer walls of the gold nano-rings. Importantly, these ring-shaped nanoparticles exhibit customizable plasmon resonances in the near-infrared spectrum, a characteristic absent in solid particles of similar sizes. This unique attribute makes the generated samples valuable for applications in Nanomedicine and Nanobiotechnology, leveraging the distinct optical properties of these nanostructures.

Keywords: nano-ring structure, nano-particles, reductant agents, plasmon resonace

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744 Magnetoresistance Transition from Negative to Positive in Functionalization of Carbon Nanotube and Composite with Polyaniline

Authors: Krishna Prasad Maity, Narendra Tanty, Ananya Patra, V. Prasad

Abstract:

Carbon nanotube (CNT) is a well-known material for very good electrical, thermal conductivity and high tensile strength. Because of that, it’s widely used in many fields like nanotechnology, electronics, optics, etc. In last two decades, polyaniline (PANI) with CNT and functionalized CNT (fCNT) have been promising materials in application of gas sensing, electromagnetic shielding, electrode of capacitor etc. So, the study of electrical conductivity of PANI/CNT and PANI/fCNT is important to understand the charge transport and interaction between PANI and CNT in the composite. It is observed that a transition in magnetoresistance (MR) with lowering temperature, increasing magnetic field and decreasing CNT percentage in CNT/PANI composite. Functionalization of CNT prevent the nanotube aggregation, improves interfacial interaction, dispersion and stabilized in polymer matrix. However, it shortens the length, breaks C-C sp² bonds and enhances the disorder creating defects on the side walls. We have studied electrical resistivity and MR in PANI with CNT and fCNT composites for different weight percentages down to the temperature 4.2K and up to magnetic field 5T. Resistivity increases significantly in composite at low temperature due to functionalization of CNT compared to only CNT. Interestingly a transition from negative to positive magnetoresistance has been observed when the filler is changed from pure CNT to functionalized CNT after a certain percentage (10wt%) as the effect of more disorder in fCNT/PANI composite. The transition of MR has been explained on the basis of polaron-bipolaron model. The long-range Coulomb interaction between two polarons screened by disorder in the composite of fCNT/PANI, increases the effective on-site Coulomb repulsion energy to form bipolaron which leads to change the sign of MR from negative to positive.

Keywords: coulomb interaction, magnetoresistance transition, polyaniline composite, polaron-bipolaron

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743 Historical Analysis of the Landscape Changes and the Eco-Environment Effects on the Coastal Zone of Bohai Bay, China

Authors: Juan Zhou, Lusan Liu, Yanzhong Zhu, Kuixuan Lin, Wenqian Cai, Yu Wang, Xing Wang

Abstract:

During the past few decades, there has been an increase in the number of coastal land reclamation projects for residential, commercial and industrial purposes in more and more coastal cities of China, which led to the destruction of the wetlands and loss of the sensitive marine habitats. Meanwhile, the influences and nature of these projects attract widespread public and academic concern. For identifying the trend of landscape (esp. Coastal reclamation) and ecological environment changes, understanding of which interacted, and offering a general science for the development of regional plans. In the paper, a case study was carried out in Bohai Bay area, based on the analysis of remote sensing data. Land use maps were created for 1954, 1970, 1981, 1990, 2000 and 2010. Landscape metrics were calculated and illustrated that the degree of reclamation changes was linked to the hydrodynamic environment and macrobenthos community. The results indicated that the worst of the loss of initial areas occurred during 1954-1970, with 65.6% lost mostly to salt field; to 2010, Coastal reclamation area increased more than 200km² as artificial landscape. The numerical simulation of tidal current field in 2003 and 2010 respectively showed that the flow velocity in offshore became faster (from 2-5 cm/s to 10-20 cm/s), and the flow direction seem to go astray. These significant changes of coastline were not conducive to the spread of pollutants and degradation. Additionally, the dominant macrobenthos analysis from 1958 to 2012 showed that Musculus senhousei (Benson, 1842) spread very fast and had been the predominant species in the recent years, which was a disturbance tolerant species.

Keywords: Bohai Bay, coastal reclamation, landscape change, spatial patterns

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742 Toxic Influence of Cypermethrin on Biochemical Changes in Fresh Water Fish, Cyprinus carpio

Authors: Gowri Balaji, Muthusamy Nachiyappan, Ramalingam Venugopal

Abstract:

Amongst the wide spectrum of pesticides, pyrethroids are preferably used rather than organochlorine, organophosphorous and carbamates pesticides due to their high effectiveness. Synthetic pyrethroids which are the chemicals used for the pest control in agriculture are now being excessively used in India. The aim of the present study was to evaluate the adverse effect of cypermethrin on the fresh water fish Cyprinus carpio, the common carp. The effect was assessed by comparing the biochemical parameters in the blood and liver tissues of control fishes with three experimental group of fishes exposed with cypermethrin for 7 days 1/15 Lc50 (E1) 1/10 Lc50 (E2) and 1/5 Lc50 values (E3). After 7 days of exposure, blood was collected and liver and gills was dissected out. The activities of acid phosphatase, alkaline phosphatase, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were estimated by standard spectrophotometric techniques in the blood, liver and gills tissue homogenate. Lactate dehydrogenase was significantly decreased in E2 and E3 experimental groups. The activities of acid phosphatase, alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase were significantly altered in the experimental groups. All the biochemical parameters studied were adversely affected in the liver and gills of cypermethrin exposed fish. The results obtained from the present study of cypermethrin exposed fishes indicate a marked toxic effect of cypermethrin and also its dose dependent impact on different organs of the fish.

Keywords: cypermethrin, Cyprinus carpio, ALT, AST, LDH, liver, gills

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741 GIS Based Atmospheric Analysis to Predict Future Temperature Rise Caused by Land Use and Land Cover in Okara by Using Environmental Remote Sensing

Authors: Sumaira Hafeez, Saira Akram

Abstract:

Albeit the populace in metropolitan regions on the planet develops each year, the urban communities battling to adapt to the expanded metropolitan movement grow at different rates. Land Surface Temperature and other atmospheric parameters of the area of not really settled using Landsat pictures more than 10 years isolated. The LULC types were moreover arranged using managed gathering techniques. Quick urbanization is changing the current examples of Land Use Land Cover (LULC) all around the world, which is thusly expanding the Land Surface Temperature (LST) other atmospheric parameters in numerous districts. Present review was centered around assessing the current and recreating the future LULC and Land Surface Temperature patterns in the elevated climate of lower Himalayan district of Pakistan. Past examples of LULC and Land Surface Temperature were distinguished through the multi-unearthly Landsat satellite pictures during the 1995–2019 information period. The future forecasts were made for the year 2030 to work out LULC and LST changes separately, utilizing their previous examples. The review presumes that the reliably extending encroachment of the city's as of late advanced provincial regions over the totally open have went with an overall warming of the district's typical. Meteorological parameters over the earlier ten years and that permitting the land to lie void for a significant long time resulting to clearing the country fields for future metropolitan improvement is a preparation that has lamentable natural effects.

Keywords: surface urban heat island, land surface temperature, urban climate change, spatial analysis of meterological and atmospheric science

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740 Does Pakistan Stock Exchange Offer Diversification Benefits to Regional and International Investors: A Time-Frequency (Wavelets) Analysis

Authors: Syed Jawad Hussain Shahzad, Muhammad Zakaria, Mobeen Ur Rehman, Saniya Khaild

Abstract:

This study examines the co-movement between the Pakistan, Indian, S&P 500 and Nikkei 225 stock markets using weekly data from 1998 to 2013. The time-frequency relationship between the selected stock markets is conducted by using measures of continuous wavelet power spectrum, cross-wavelet transform and cross (squared) wavelet coherency. The empirical evidence suggests strong dependence between Pakistan and Indian stock markets. The co-movement of Pakistani index with U.S and Japanese, the developed markets, varies over time and frequency where the long-run relationship is dominant. The results of cross wavelet and wavelet coherence analysis indicate moderate covariance and correlation between stock indexes and the markets are in phase (i.e. cyclical in nature) over varying durations. Pakistan stock market was lagging during the entire period in relation to Indian stock market, corresponding to the 8~32 and then 64~256 weeks scale. Similar findings are evident for S&P 500 and Nikkei 225 indexes, however, the relationship occurs during the later period of study. All three wavelet indicators suggest strong evidence of higher co-movement during 2008-09 global financial crises. The empirical analysis reveals a strong evidence that the portfolio diversification benefits vary across frequencies and time. This analysis is unique and have several practical implications for regional and international investors while assigning the optimal weightage of different assets in portfolio formulation.

Keywords: co-movement, Pakistan stock exchange, S&P 500, Nikkei 225, wavelet analysis

Procedia PDF Downloads 346
739 Solar-Blind Ni-Schottky Photodetector Based on MOCVD Grown ZnGa₂O₄

Authors: Taslim Khan, Ray Hua Horng, Rajendra Singh

Abstract:

This study presents a comprehensive analysis of the design, fabrication, and performance evaluation of a solar-blind Schottky photodetector based on ZnGa₂O₄ grown via MOCVD, utilizing Ni/Au as the Schottky electrode. ZnGa₂O₄, with its wide bandgap of 5.2 eV, is well-suited for high-performance solar-blind photodetection applications. The photodetector demonstrates an impressive responsivity of 280 A/W, indicating its exceptional sensitivity within the solar-blind ultraviolet band. One of the device's notable attributes is its high rejection ratio of 10⁵, which effectively filters out unwanted background signals, enhancing its reliability in various environments. The photodetector also boasts a photodetector responsivity contrast ratio (PDCR) of 10⁷, showcasing its ability to detect even minor changes in incident UV light. Additionally, the device features an outstanding detective of 10¹⁸ Jones, underscoring its capability to precisely detect faint UV signals. It exhibits a fast response time of 80 ms and an ON/OFF ratio of 10⁵, making it suitable for real-time UV sensing applications. The noise-equivalent power (NEP) of 10^-17 W/Hz further highlights its efficiency in detecting low-intensity UV signals. The photodetector also achieves a high forward-to-backward current rejection ratio of 10⁶, ensuring high selectivity. Furthermore, the device maintains an extremely low dark current of approximately 0.1 pA. These findings position the ZnGa₂O₄-based Schottky photodetector as a leading candidate for solar-blind UV detection applications. It offers a compelling combination of sensitivity, selectivity, and operational efficiency, making it a highly promising tool for environments requiring precise and reliable UV detection.

Keywords: wideband gap, solar blind photodetector, MOCVD, zinc gallate

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