Search results for: stress concentration

Authors: Vidit Mohan, Ashwin P. Ramesh, Anirudh Toshniwal

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Alkali-Surfactant-Alternate-Gas(ASAG) injection, a novel EOR process has the potential to improve displacement efficiency over Surfactant-Alternate-Gas(SAG) by addressing the problem of surfactant adsorption by clay minerals in rock matrix. A detailed laboratory investigation on ASAG injection process was carried out with encouraging results. To further enhance recovery over WAG injection process, SAG injection was investigated at laboratory scale. SAG injection yielded marginal incremental displacement efficiency over WAG process. On investigation, it was found that, clay minerals in rock matrix adsorbed the surfactants and were detrimental for SAG process. Hence, ASAG injection was conceptualized using alkali as a clay stabilizer. The experiment of ASAG injection with surfactant concentration of 5000 ppm and alkali concentration of 0.5 weight% yields incremental displacement efficiency of 5.42% over WAG process. The ASAG injection is a new process and has potential to enhance efficiency of WAG/SAG injection process.

Keywords: alkali surfactant alternate gas (ASAG), surfactant alternate gas (SAG), laboratory investigation, EOR process

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Authors: Anwar Beg, Sireetorn Kuharat, Rashid Mehmood, Rabil Tabassum, Meisam Babaie

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Nano-polymeric solar paints and sol-gels have emerged as a major new development in solar cell/collector coatings offering significant improvements in durability, anti-corrosion and thermal efficiency. They also exhibit substantial viscosity variation with temperature which can be exploited in solar collector designs. Modern manufacturing processes for such nano-rheological materials frequently employ stagnation flow dynamics under high temperature which invokes radiative heat transfer. Motivated by elaborating in further detail the nanoscale heat, mass and momentum characteristics of such sol gels, the present article presents a mathematical and computational study of the steady, two-dimensional, non-aligned thermo-fluid boundary layer transport of copper metal-doped water-based nano-polymeric sol gels under radiative heat flux. To simulate real nano-polymer boundary interface dynamics, thermal slip is analysed at the wall. A temperature-dependent viscosity is also considered. The Tiwari-Das nanofluid model is deployed which features a volume fraction for the nanoparticle concentration. This approach also features a Maxwell-Garnet model for the nanofluid thermal conductivity. The conservation equations for mass, normal and tangential momentum and energy (heat) are normalized via appropriate transformations to generate a multi-degree, ordinary differential, non-linear, coupled boundary value problem. Numerical solutions are obtained via the stable, efficient Runge-Kutta-Fehlberg scheme with shooting quadrature in MATLAB symbolic software. Validation of solutions is achieved with a Variational Iterative Method (VIM) utilizing Langrangian multipliers. The impact of key emerging dimensionless parameters i.e. obliqueness parameter, radiation-conduction Rosseland number (Rd), thermal slip parameter (α), viscosity parameter (m), nanoparticles volume fraction (ϕ) on non-dimensional normal and tangential velocity components, temperature, wall shear stress, local heat flux and streamline distributions is visualized graphically. Shear stress and temperature are boosted with increasing radiative effect whereas local heat flux is reduced. Increasing wall thermal slip parameter depletes temperatures. With greater volume fraction of copper nanoparticles temperature and thermal boundary layer thickness is elevated. Streamlines are found to be skewed markedly towards the left with positive obliqueness parameter.

Keywords: non-orthogonal stagnation-point heat transfer, solar nano-polymer coating, MATLAB numerical quadrature, Variational Iterative Method (VIM)

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Authors: Umang H. Gajjar, K. M. Khambholja, R. K. Patel

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Semecarpus anacardium shows the presence of bioflavonoids, phenolic compounds, bhilawanols, minerals, vitamins and amino acids. Detoxified S. anacardium and its oils are considered to have anti-inflammatory properties and used in nervous debility, neuritis, rheumatism and leprous modules. S. anacardium if used without purification causes toxic skin inflammation problem because it contains toxic phenolic oil. During this Shodhana Process - An ayurvedic purification method, toxic phenolic oil was removed, have marked effect on the concentration of the phytoconstituent & antioxidant activity of S. anacardium. Total phenolic content decreased up to 70 % (from 28.9 %w/w to 8.94 %w/w), while there is a negligible effect on the concentration of total flavonoid (7.51 %w/w to 7.43 %w/w) and total carbohydrate (0.907 %w/w to 0.853 % w/w) content. IC50& EC50 value of extract of S. anacardium before and after purification are 171.7 & 314.3 while EC50values are 280.μg/ml & 304. μg/ml, shows that antioxidant activity of S. anacardium is decreased but the safety profile of the drug is increased as the toxic phenolic oil was removed during Shodhana - An ayurvedic purification method.

Keywords: Semecarpus anacardium, Shodhana process, safety profile, improvement

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Authors: Pallavi Moudgil, J. S. Bedi, R. S. Aulakh, J. P. S. Gill

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Mycotoxins in milk are of major public health concern. The present study was envisaged with an aim to monitor the occurrence of aflatoxin M1 and ochratoxin A in raw milk samples collected from individual animals from dairy farms located in Punjab (India). A total of 168 raw milk samples were collected and analysed using competitive ELISA kits. Out of these, 9 (5.4%) samples were found positive for aflatoxin M1 with the mean concentration of 0.006-0.13 ng/ml and 2 (1.2%) samples exceeded the established maximum residue limit of 0.05 ng/ml established by the European Union. For ochratoxin A, 2 (0.1%) samples were found positive with the mean concentration of 0.61-0.83 ng/ml with both the samples below the established maximum residue limit of 2 ng/ml. The results showed that the milk of dairy cattle is safe with respect to ochratoxin A contamination but occurrence of aflatoxin M1 above maximum residue limit suggested that feed contaminated with mycotoxins might have been offered to dairy cattle that can pose serious health risks to consumers.

Keywords: Aflatoxin M1, health risks, maximum residue limit, milk, Ochratoxin A

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Authors: B. G. Muhammad, S. M. Jafar

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Neutron Activation Analysis (NAA) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were employed to analyze the level of trace elements concentrations in sediment samples and their bioaccumulation in some aquatic species selected randomly from surface water resources in the Northern peninsula of Malaysia. The NAA results of the sediment samples indicated a wide range in concentration of different elements were observed. Fe, K, and Na were found to have major concentration values that ranges between 61,000 ± 1400 to 4,500 ± 100 ppm, 20100±1000 to 3100±600 and 3,100±600 and 200±10 ppm, respectively. Traces of heavy metals with much more contamination health concern, such as Cr and As, were also identified in many of the samples analyzed. The average specific activities of 40K, 232Th and 226Ra in soil and the corresponding radium equivalent activity and the external hazard index were all found to be lower than the maximum permissible limits (370 Bq kg-1 and 1).

Keywords: external hazard index, Neutron Activation Analysis, radium equivalent, trace elements concentrations

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Authors: Meriem Mansouri, Fatiha Bendali Saoudi, Noureddine Soltani

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Biological control presents a means of control for the protection of the environment. Bacillus thuringiensis israelensis Berliner 1915 is an inseticide of biological origin because it is a bacterium of the Bacillaceae family. This biocide has a biological importance, because of its specific larvicidal action against Culicidae, blood-sucking insects, responsible for several diseases to humans and animals through the world. As well as, its high specificity for these insects. Also, the freshwater mites, this necessarily parasitic group for aquatic species such as the Physidae, also have an effective biological control against the Culicidae, because of their voracious predation to the larvae of these insects. The present work aims to study the effects of the biocide Bacillus thuringiensis var israelinsis, against non-target adults of water mites Eylais hamata Koenike, 1897, as well as its associated host species Physa marmorata Fitzinger, 1833. After 12 days of oral treatment of adults with lethal concentration (LC50:0.08µg/ml), determined from essays on 4th instar larvae of Culex pipiens (hematophagous insects). No adverse effect has been recorded for adult individuals of Eylais hamata, contrary, snail Physa marmorata were sensitive for this dose of Bti. In parallel, after treatment at the Bti by LC50, the enzyme stress bio marker glutathione S-transferase, was measured after 24, 48 and 72 hours. The enzymatic activity of GST has increased after 24 and 48 hours following treatment.

Keywords: biological control, Bacillus thuringiensis var israelinsis, culicidae, hydrachnidia, enzymatic activity

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Authors: Mohamed Ayeldeen, Abdelazim Negm

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Nowadays, strength characteristics of soils have more importance due to increasing building loads. In some projects, geotechnical properties of the soils are be improved using man-made materials varying from cement-based to chemical-based. These materials have proven successful in improving the engineering properties of the soil such as shear strength, compressibility, permeability, bearing capacity etc.. However, the use of these artificial injection formulas often modifies the pH level of soil, contaminates soil and groundwater. This is attributed to their toxic and hazardous characteristics. Recently, an environmentally friendly soil treatment method or Biological Treatment Method (BTM) was to bond particles of loose sandy soils. This research paper presents the preliminary results of using biopolymers for strengthening cohesionless soil. Xanthan gum was identified for further study over a range of concentrations varying from 0.25% to 2.00%. Xanthan gum is a polysaccharide secreted by the bacterium Xanthomonas campestris, used as a food additive and it is a nontoxic material. A series of direct shear, unconfined compressive strength, and permeability tests were carried out to investigate the behavior of sandy soil treated with Xanthan gum with different concentration ratios and at different curing times. Laser microscopy imaging was also conducted to study the microstructure of the treated sand. Experimental results demonstrated the compatibility of Xanthan gum to improve the geotechnical properties of sandy soil. Depending on the biopolymer concentration, it was observed that the biopolymers effectively increased the cohesion intercept and stiffness of the treated sand and reduced the permeability of sand. The microscopy imaging indicates that the cross-links of the biopolymers through and over the soil particles increase with the increase of the biopolymer concentration.

Keywords: biopolymer, direct shear, permeability, sand, shear strength, Xanthan gum

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Authors: Ravinder Singh, C Rajesh, Saroj Badhan, Shailendra Mishra, Ranjit Singh Kataria

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Heat shock protein 60 and 70 are crucial chaperones that guide appropriate folding of denatured proteins under heat stress conditions. HSP60 and HSP70 provide assistance in correct folding of a multitude of denatured proteins. The heat shock factors are the family of some transcription factors which controls the regulation of gene expression of proteins involved in folding of damaged or improper folded proteins during stress conditions. Under normal condition heat shock proteins bind with HSF-1 and act as its repressor as well as aids in maintaining the HSF-1’s nonactive and monomeric confirmation. The experimental protein structure for all these proteins in Bubalus bubalis is not known till date. Therefore computational approach was explored to identify three-dimensional structure analysis of all these proteins. In this study, an extensive in silico analysis has been performed including sequence comparison among species to comparative modeling of Bubalus bubalis HSP60, HSP70 and HSF-1 protein. The stereochemical properties of proteins were assessed by utilizing several scrutiny bioinformatics tools to ensure model accuracy. Further docking approach was used to study interactions between Heat shock proteins and HSF-1.

Keywords: Bubalus bubalis, comparative modelling, docking, heat shock protein

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Authors: Faisal Saleem, Kui Zhang, Adam Harvey

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The role of N₂ carrier gas towards the conversion of tar analogue was studied in a non-thermal plasma dielectric barrier discharge (DBD) reactor. The important parameters such as power (5-40W), residence time (1.41-4.23 s), concentration (20-82 g/Nm³), and temperature (Ambient-400°C) were explored. The present study demonstrated that plasma power and residence time played a key role in the decomposition of toluene, and almost complete removal of toluene was observed at 40w and 4.23 s. H₂ is obtained as a major gaseous product with a maximum selectivity of 40% along with some lighter hydrocarbons (5.5%). The removal efficiency of toluene slightly decreases with increasing the concentration of toluene from 20 g/Nm³ to 82 g/Nm³. The solid residue formation takes place inside the plasma reactor. The selectivity of LHC (lower hydrocarbons) increased up to 15% by increasing the temperature to 400°C. Introducing H₂ to the gas at elevated temperature opens up new reaction routes to raise the selectivity to lower hydrocarbons. The selectivity to methane reaches to 42% using 35% H₂ at 400°C and total selectivity of LHC increases to 57%.

Keywords: biomass gasification tar, non-thermal plasma, dielectric barrier discharge, residence time

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Authors: Meral Huri, Sedef Şahin

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Post-traumatic stress disorder (PTSD) is characterized by psychiatric symptoms and triggered by a terrifying experience which may immediately effect cognitive, affective, behavioral and social skills of the individual. One of the most common noncutaneous cancer among men is prostate cancer. The incidence of psychological stress is quite common in men with prostate cancer. The aim of the study was to explore the PTSD frequency among prostate cancer and define the relationship between occupational participation, coping skills and level of perceived social support among patients with prostate cancer. Forty patients diagnosed with prostate cancer were included in the study. After dividing the patients into two groups ( study/ control) according to type of tumor, we recorded their characteristics and evaluations differences. We evaluated the demographic information form, Structured Clinical Interview for DSM-IV (SCID- I)- Clinical Version for PTSD, Multidimensional Scale of Perceived Social Support, Styles of Coping Inventory and Canadian Occupational Performance Measure (COPM) before and after 1 month from surgery. The mean age of the study group (n:18) was 65.85.6 years (range: 61-79 years). The mean age of the control group (n: 22) was a little bit higher than the study group with mean age 71.3±6.9 years (range: 60-85 years). There was no statistically significant difference between the groups for age and the other characteristics. According to the results of the study, statistically significant difference was found between the level of PTSD of study and the control group. 22% of study group showed PTSD while 13% of the control group showed PTSD (r: 0.02, p<0.001). The scores of study group and control group showed statistically significant difference in five sub-categories of Styles of Coping Inventory. Patients with prostate cancer showed decreased scores in optimistic, seeking social supports and self-confident approach, while increased scores in helpless and submissive sub-categories than the control group (p<0.001). The scores of Multidimensional Scale of Perceived Social Supports of study group and control group showed statistically significant difference. The total perceived social supports score of the study group was 71.34 ± 0.75 while it was 75.34 ± 0.64 for the control group. Total and the sub-category scores of study group were statistically significant lower than the control group. According to COPM, mean scores of occupational participation of study group for occupational performance were 4.32±2.24 and 7.01±1.52 for the control group, respectively). Mean Satisfaction scores were 3,22±2.31 and 7.45±1.74 for the study and control group, respectively. The patients with prostate cancer and benign prostate hyperplasia (BPH) did not show any statistically difference in activity performance (r:0.87) while patients with prostate cancer showed statistically lower scores than the patients with BPH in activity satisfaction (r:0.02, p<0.001).Psycho-social occupational therapy interventions might help to decrease the prevalence of PTSD by increasing associated factors such as the social support perception, using coping skills and activity participation of patients with prostate cancer.

Keywords: activity performance, occupational therapy, posttraumatic stress disorder, prostate cancer

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Authors: Ismail Mahdi, Nidal Fahsi, Mohamed Hafidi, Abdelmounaim Allaoui, Latefa Biskri

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To meet the worldwide demand for food, smart management of arable lands is needed. This could be achieved through sustainable approaches such as the use of plant growth-promoting microorganisms including bacteria. Phosphate (P) solubilization is one of the major mechanisms of plant growth promotion by associated bacteria. In the present study, we isolated and screened 14 strains from the rhizosphere of Chenopodium quinoa wild grown in the experimental farm of UM6P and assessed their plant growth promoting properties. Next, they were identified by using 16S rRNA and Cpn60 genes sequencing as Bacillus, Pseudomonas and Enterobacter. These strains showed dispersed capacities to solubilize P (up to 346 mg L−1) following five days of incubation in NBRIP broth. We also assessed their abilities for indole acetic acid (IAA) production (up to 795,3 µg ml−1) and in vitro salt tolerance. Three Bacillus strains QA1, QA2, and S8 tolerated high salt stress induced by NaCl with a maximum tolerable concentration of 8%. Three performant isolates, QA1, S6 and QF11, were further selected for seed germination assay because of their pronounced abilities in terms of P solubilization, IAA production and salt tolerance. The early plant growth potential of tested strains showed that inoculated quinoa seeds displayed greater germination rate and higher seedlings growth under bacterial treatments. The positive effect on seed germination traits strongly suggests that the tested strains are growth promoting, halotolerant and P solubilizing bacteria which could be exploited as biofertilizers.

Keywords: phosphate solubilizing bacteria, IAA, Seed germination, salt tolerance, quinoa

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Authors: L. J. de Bessa Neto, V. S. Filho, J. V. Ferreira Nunes, G. C. Bergamo

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There are many situations in which human activities have significant effects on the environment. Damage to the ozone layer is one of them. The objective of this work is to use the Least Squares Method, considering the linear, exponential, logarithmic, power and polynomial models of the second degree, to analyze through the coefficient of determination (R²), which model best fits the behavior of the chlorodifluoromethane (HCFC-142b) in parts per trillion between 1992 and 2018, as well as estimates of future concentrations between 5 and 10 periods, i.e. the concentration of this pollutant in the years 2023 and 2028 in each of the adjustments. A total of 809 observations of the concentration of HCFC-142b in one of the monitoring stations of gases precursors of the deterioration of the ozone layer during the period of time studied were selected and, using these data, the statistical software Excel was used for make the scatter plots of each of the adjustment models. With the development of the present study, it was observed that the logarithmic fit was the model that best fit the data set, since besides having a significant R² its adjusted curve was compatible with the natural trend curve of the phenomenon.

Keywords: chlorodifluoromethane (HCFC-142b), ozone, least squares method, regression models

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Authors: Aswin Kumar Krishnan, Yat Choy Wong, Reiza Mukhlis, Zipeng Zhang, Arul Arulrajah

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The continuous increase in vehicle uptake escalates the number of rubber tyre waste which need to be managed to avoid landfilling and stockpiling. The present research focused on the sustainable use of rubber crumbs in clay roof tiles. The properties of roof tiles composed of clay, rubber crumbs, NaOH, and Na₂SiO₃ with a 10% alkaline activator were studied. Tile samples were fabricated by heating the compacted mixtures at 50°C for 72 hours, followed by a higher heating temperature of 200°C for 24 hours. The effect of rubber crumbs aggregates as a substitution for the raw clay materials was investigated by varying their concentration from 0% to 2.5%. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been conducted to study the phases and microstructures of the samples. It was found that the optimum rubber crumbs concentration was at 0.5% and 1%, while cracks and larger porosity were found at higher crumbs concentrations. Water absorption and compressive strength test results demonstrated that rubber crumbs and clay satisfied the standard requirement for the roof tiles.

Keywords: rubber crumbs, clay, roof tiles, alkaline activators

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Authors: Timur S. Zaripov, Artur K. Gilfanov, Sergei S. Sazhin, Steven M. Begg, Morgan R. Heikal

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The calculation of the concentration of inertial droplets in complex flows is encountered in the modelling of numerous engineering and environmental phenomena; for example, fuel droplets in internal combustion engines and airborne pollutant particles. The results of recent research, focused on the development of methods for calculating concentration and their implementation in the commercial CFD code, ANSYS Fluent, is presented here. The study is motivated by the investigation of the mixture preparation processes in internal combustion engines with direct injection of fuel sprays. Two methods are used in our analysis; the Fully Lagrangian method (also known as the Osiptsov method) and the Eulerian approach. The Osiptsov method predicts droplet concentrations along path lines by solving the equations for the components of the Jacobian of the Eulerian-Lagrangian transformation. This method significantly decreases the computational requirements as it does not require counting of large numbers of tracked droplets as in the case of the conventional Lagrangian approach. In the Eulerian approach the average droplet velocity is expressed as a function of the carrier phase velocity as an expansion over the droplet response time and transport equation can be solved in the Eulerian form. The advantage of the method is that droplet velocity can be found without solving additional partial differential equations for the droplet velocity field. The predictions from the two approaches were compared in the analysis of the problem of a dilute gas-droplet flow around an infinitely long, circular cylinder. The concentrations of inertial droplets, with Stokes numbers of 0.05, 0.1, 0.2, in steady-state and transient laminar flow conditions, were determined at various Reynolds numbers. In the steady-state case, flows with Reynolds numbers of 1, 10, and 100 were investigated. It has been shown that the results predicted using both methods are almost identical at small Reynolds and Stokes numbers. For larger values of these numbers (Stokes — 0.1, 0.2; Reynolds — 10, 100) the Eulerian approach predicted a wider spread in concentration in the perturbations caused by the cylinder that can be attributed to the averaged droplet velocity field. The transient droplet flow case was investigated for a Reynolds number of 200. Both methods predicted a high droplet concentration in the zones of high strain rate and low concentrations in zones of high vorticity. The maxima of droplet concentration predicted by the Osiptsov method was up to two orders of magnitude greater than that predicted by the Eulerian method; a significant variation for an approach widely used in engineering applications. Based on the results of these comparisons, the Osiptsov method has resulted in a more precise description of the local properties of the inertial droplet flow. The method has been applied to the analysis of the results of experimental observations of a liquid gasoline spray at representative fuel injection pressure conditions. The preliminary results show good qualitative agreement between the predictions of the model and experimental data.

Keywords: internal combustion engines, Eulerian approach, fully Lagrangian approach, gasoline fuel sprays, droplets and particle concentrations

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Authors: Seyed Mohammad Asgharzadeh, Moein Biglari

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Asphalt overlay is the most commonly used technique of pavement rehabilitation. However, the reflective cracks which occur on the overlay surface after a short period of time are the most important distresses threatening the durability of new overlays. Stress Absorbing Membrane Interlayers (SAMIs) are used to postpone the reflective cracking in the overlays. Sand asphalt mixtures, in unmodified or crumb rubber modified (CRM) conditions, can be used as an SAMI material. In this research, the performance properties of different SAMI applications were evaluated in the laboratory using an Indirect Tensile (IDT) fracture energy. The IDT fracture energy of sand asphalt samples was also evaluated and then compared to that of the regular dense graded asphalt used as an overlay. Texas boiling water and modified Lottman tests were also conducted to evaluate the moisture susceptibility of sand asphalt mixtures. The test results showed that sand asphalt mixtures can stand higher levels of energy before cracking, and this is even more pronounced for the CRM sand mix. Sand asphalt mixture using CRM binder was also shown to be more resistance to moisture induced distresses.

Keywords: SAMI, sand asphalt, crumb rubber, indirect tensile test

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Authors: Sebastian Leal-Arenas

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English uses in-situ Nuclear Stress (NS) to express the meanings of theticity and focus. The NS is phonetically represented by an increase in duration, intensity, and pitch range. On the other hand, Spanish conveys the same meanings by aligning the constituent that carries the NS to the end of the sentence via word-order movement. However, little is known about heritage speakers’ production of theticity and focus in English or Spanish. The present study investigates heritage speakers’ production of thetic and subject focus statements. Participants (n = 11) were heritage speakers of Spanish with varying proficiency enrolled in a writing course at a university in the United States. In the production task, participants observed contextualized images and uttered a sentence to answer a provided question. Duration, intensity, and F0 peak were the correlates to stress considered in this investigation. Results indicated that participants tended to present an intonation closer to what is expected in English monolinguals in subject-focus statements than in thetic sentences. However, participants with lower Spanish proficiency used in-situ NS placement in thetic statements more often than those with higher proficiency. Results are discussed in terms of the production patterns observed in heritage speakers with emphasis on the role of language dominance.

Keywords: focus, heritage speakers, prosody, theticity

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Authors: Ahmad Abdi, M. Golzadeh Gangeraj, Alireza Barari, S. Shirali, S. Amini

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Aims: Diabetes is one of the common metabolic diseases in the world that has the dire adverse effects such as nephropathy, retinopathy and cardiovascular problems. Pharmaceutical and non-pharmaceutical strategies for control and treatment of diabetes are provided. Exercise and nutrition as non-drug strategies for the prevention and control of diabetes are considered. Exercises may increase oxidative stress and myocardium injury, thus it is necessary to take nutrition strategies to help diabetic athletes. Methods: This study was a semi-experimental research. Therefore, 24 men with type 2 diabetes were selected and randomly divided in four groups (1. control, 2. saffron extract, 3. aerobic exercises, 4. compound aerobic exercises and saffron extract). Saffron extract with 100 mg/day was used. Aerobic exercises, three days a week, for eight weeks, with 55-70% of maximum heart rate were performed. At the end, levels of Heart-type fatty acid-binding protein (HFABP) and Troponin T were measured. Data were analyzed by Paired t, One-way ANOVA and Tukey tests. Results: The serum Troponin T increased significantly in saffron extract, aerobic exercises and compound saffron extract -aerobic exercises in type 2 diabetic men(P=0.024, P =0.013, P=0.005 respectively). Saffron extract consumption (100 mg/day) and aerobic exercises did not significantly influence the serum HFABP (P =0.365, P =0.188 respectively). But serum HFABP decreased significantly in compound saffron extract -aerobic exercises group (P =0.003). Conclusions: Raised cardiac Troponin T and HFABP concentration accepted as the standard biochemical markers for the diagnosis of cardiac injury. Saffron intake may beneficially protect the myocardium from injuries. Compound saffron extract -aerobic exercises can decrease levels of Troponin T and HFABP in men with type 2 diabetes.

Keywords: Saffron, aerobic exercises, type 2 diabetes, HFABP, troponin T

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Authors: Farida Kaouah, Wassila Hachi, Lamia Brahmi, Chahida Ousselah, Salim Boumaza, Mohamed Trari

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The feasibility of using solar irradiation instead of UV light in photocatalysis is a promising approach for water treatment. In this study, photocatalytic degradation of a widely used textile dye, Acid Blue 25 (AB25), with noble metal loaded ZnO photocatalyst (Ag/ZnO), was investigated in aqueous suspension under solar light. The results showed that the deposition of Ag as a noble metal onto the ZnO surface, improved the photodegradation of AB25. . The effect of different parameters such as catalyst dose, initial dye concentration, and contact time was optimized and the optimal degradation of AB25 (97%) was achieved for initial AB25 concentration of 24 mg L−1 an catalyst dose of 1 g L−1 at natural pH (5.42) after 180 min. The kinetic studies were achieved and revealed that the photocatalytic degradation process obeyed to Langmuir–Hinshelwood model and followed a pseudo-first order rate expression. This work envisages the great potential that sunlight photocatalysis has in the degradation of dyes from wastewater

Keywords: acid dye, photocatalytic degradation, sunlight, zinc oxide, noble metal, Langmuir–Hinshelwood model

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Authors: Vaso K. Kapnopoulou, Piero Caridis

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The fatigue of ship structural details is of major concern in the maritime industry as it can generate fracture issues that may compromise structural integrity. In the present study, a fatigue analysis of the lower hopper knuckle connection of a bulk carrier was conducted using the Finite Element Method by means of ABAQUS/CAE software. The fatigue life was calculated using Miner’s Rule and the long-term distribution of stress range by the use of the two-parameter Weibull distribution. The cumulative damage ratio was estimated using the fatigue damage resulting from the stress range occurring at each load condition. For this purpose, a cargo hold model was first generated, which extends over the length of two holds (the mid-hold and half of each of the adjacent holds) and transversely over the full breadth of the hull girder. Following that, a submodel of the area of interest was extracted in order to calculate the hot spot stress of the connection and to estimate the fatigue life of the structural detail. Two hot spot locations were identified; one at the top layer of the inner bottom plate and one at the top layer of the hopper plate. The IACS Common Structural Rules (CSR) require that specific dynamic load cases for each loading condition are assessed. Following this, the dynamic load case that causes the highest stress range at each loading condition should be used in the fatigue analysis for the calculation of the cumulative fatigue damage ratio. Each load case has a different effect on ship hull response. Of main concern, when assessing the fatigue strength of the lower hopper knuckle connection, was the determination of the maximum, i.e. the critical value of the stress range, which acts in a direction normal to the weld toe line. This acts in the transverse direction, that is, perpendicularly to the ship's centerline axis. The load cases were explored both theoretically and numerically in order to establish the one that causes the highest damage to the location examined. The most severe one was identified to be the load case induced by beam sea condition where the encountered wave comes from the starboard. At the level of the cargo hold model, the model was assumed to be simply supported at its ends. A coarse mesh was generated in order to represent the overall stiffness of the structure. The elements employed were quadrilateral shell elements, each having four integration points. A linear elastic analysis was performed because linear elastic material behavior can be presumed, since only localized yielding is allowed by most design codes. At the submodel level, the displacements of the analysis of the cargo hold model to the outer region nodes of the submodel acted as boundary conditions and applied loading for the submodel. In order to calculate the hot spot stress at the hot spot locations, a very fine mesh zone was generated and used. The fatigue life of the detail was found to be 16.4 years which is lower than the design fatigue life of the structure (25 years), making this location vulnerable to fatigue fracture issues. Moreover, the loading conditions that induce the most damage to the location were found to be the various ballasting conditions.

Keywords: dynamic load cases, finite element method, high cycle fatigue, lower hopper knuckle

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Authors: Mujahid Farid, Shafaqat Ali, Muhammad Bilal Shakoor

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Heavy metals pollution of soil is a prevalent global problem and oilseed rape (Brassica napus L.) are considered useful for the restoration of metal contaminated soils. Phytoextraction is an in-situ environment-friendly technique for the clean-up of contaminated soils. Response to cadmium (Cd) toxicity in combination with a chelator, Ethylenediamminetetraacetic acid (EDTA) was studied in oilseed rape grown hydroponically in greenhouse conditions under three levels of Cd (0, 10, and 50 µM) and two levels of EDTA (0 and 2.5 mM). Cd decreased plant growth, biomass and chlorophyll concentrations while the application of EDTA enhanced plant growth by reducing Cd-induced effects in Cd-stressed plants. Significant decrease in photosynthetic parameters was found by the Cd alone. Addition of EDTA improved the net photosynthetic and gas exchange capacity of plants under Cd stress. Cd at 10 and 50 μM significantly increased electrolyte leakage, the production of hydrogen peroxidase (H2O2) and malondialdehyde (MDA) and a significant reduction was observed in the activities of catalase (CAT), guaiacol peroxidase (POD), ascorbate peroxidase (APX), and superoxide dismutase under Cd stress plants. Application of EDTA at the rate of 2.5 mM alone and with combination of Cd increased the antioxidant enzymes activities and reduced the electrolyte leakage and production of H2O2 and MDA. Oilseed rape (Brassica napus L.) actively accumulated Cd in roots, stems and leaves and the addition of EDTA boosted the uptake and accumulation of Cd in oil seed rape by dissociating Cd in culture media. The present results suggest that under 8 weeks Cd-induced stress, application of EDTA significantly improve plant growth, chlorophyll content, photosynthetic, gas exchange capacity, improving enzymes activities and increased the metal uptake in roots, stems and leaves of oilseed rape (Brassica napus L.) respectively.

Keywords: antioxidant enzymes, cadmium, chelator, EDTA, growth, oilseed rape

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Authors: Ali Ahmad AlGassim

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The objective of this study is to explore the local community perceptions toward the impact of tourism from the COR theory perspective. The current study used qualitative methods and purposive sampling to engage informants. Data was collected using an online survey with closed-ended and open-ended questions from 57 informants living in Al-Jufa Village, and then data was analysed using content analysis. The findings showed that COR theory help explains the residents’ perception of the threat and stress of losing resources. The findings showed the residents feel stressed about losing resources, such as lands, houses, heritage, sociocultural and Islamic values, as well as job and investment opportunities if the village is developed for tourism. Findings also present that one group of residents declared rejections and aiming to resist the development if it takes place, and they will not allowing foreigners to come and live in the village. The findings also show that this stress and strain can be alleviated by allowing residents to participate in the development. Finally, the residents of Al-Juhfa showed a high level of feeling of ownership towards their resources.

Keywords: perception of threat, effect of tourism, COR theory, local community, impact of tourism, Saudi Arabia

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Authors: Likith Reddy Pinninti, Fredrik Ribsskog Staven, Leslie Robert Noble, Jorge Manuel de Oliveira Fernandes, Deepti Manjari Patel, Torstein Kristensen

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Understanding fish behavior is essential to improve animal welfare in aquaculture research. Behavioral traits can have a strong influence on fish health and habituation. To identify the genes and biological pathways responsible for lumpfish behavior, we performed an experiment to understand the interspecies relationship (mutualism) between the lumpfish and salmon. Also, we tested the correlation between the gene expression data vs. observational/physiological data to know the essential genes that trigger stress and swimming behavior in lumpfish. After the de novo assembly of the brain transcriptome, all the samples were individually mapped to the available lumpfish (Cyclopterus lumpus L.) primary genome assembly (fCycLum1.pri, GCF_009769545.1). Out of ~16749 genes expressed in brain samples, we found 267 genes to be statistically significant (P > 0.05) found only in odor and control (1), model and control (41) and salmon and control (225) groups. However, genes with |LogFC| ≥0.5 were found to be only eight; these are considered as differentially expressed genes (DEG’s). Though, we are unable to find the differential genes related to the behavioral traits from RNA-Seq data analysis. From the correlation analysis, between the gene expression data vs. observational/physiological data (serotonin (5HT), dopamine (DA), 3,4-Dihydroxyphenylacetic acid (DOPAC), 5-hydroxy indole acetic acid (5-HIAA), Noradrenaline (NORAD)). We found 2495 genes found to be significant (P > 0.05) and among these, 1587 genes are positively correlated with the Noradrenaline (NORAD) hormone group. This suggests that Noradrenaline is triggering the change in pigmentation and skin color in lumpfish. Genes related to behavioral traits like rhythmic, locomotory, feeding, visual, pigmentation, stress, response to other organisms, taxis, dopamine synthesis and other neurotransmitter synthesis-related genes were obtained from the correlation analysis. In KEGG pathway enrichment analysis, we find important pathways, like the calcium signaling pathway and adrenergic signaling in cardiomyocytes, both involved in cell signaling, behavior, emotion, and stress. Calcium is an essential signaling molecule in the brain cells; it could affect the behavior of fish. Our results suggest that changes in calcium homeostasis and adrenergic receptor binding activity lead to changes in fish behavior during stress.

Keywords: behavior, De novo, lumpfish, salmon

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Authors: Qi Wang

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Chinese has become a powerful worldwide language and millions of learners are studying it all over the words. Chinese is a tone language with unique meaningful characters, which makes foreign learners master it with more difficulties. On the other hand, as each foreign language, the learners of Chinese first will learn the basic Chinese Sound Structure (the initials and finals, tones, Neutral Tone and Tone Sandhi). It’s quite common that in the following studies, teachers made a lot of efforts on drilling and error correcting, in order to help students to pronounce correctly, but ignored the training of suprasegmental features (e.g. stress, intonation). This paper analysed the oral data based on our graduation students (two-year program) from 2006-2013, presents the intonation pattern of our graduates to speak Chinese as second language -high and plain with heavy accents, without lexical stress, appropriate stop endings and intonation, which led to the misunderstanding in different real contexts of communications and the international official Chinese test, e.g. HSK (Chinese Proficiency Test), HSKK (HSK Speaking Test). This paper also demonstrated how the Chinese to use the suprasegmental features strategically in different functions and moods (declarative, interrogative, imperative, exclamatory and rhetorical intonations) in order to train the learners to achieve better Communicative Performance.

Keywords: second language learning, suprasegmental, communication, HSK (Chinese Proficiency Test)

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Authors: K. S. Ghosh, Sagnik Bose, Kapil Tripati

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Potentiodynamic polarization studies carried out on AA2024 and AA2014 Al-Cu-Mg alloys of various tempers in 3.5 wt. % NaCl and in 3.5 wt. % NaCl + 1.0 % H2O2 solution characteristic E-i curves. Corrosion potential (Ecorr) value has shifted towards more negative potential with the increase of artificial aging time. The Ecorr value for the alloy tempers has also shifted anodically in presence of H2O2 in 3.5 % NaCl solution. Further, passivity phenomenon has been observed in all the alloy tempers when tested in 3.5 wt. % NaCl solution at pH 12. Stress corrosion cracking (SCC) behaviour of friction stir weld (FSW) joint of AA2014 alloy has been studied bu slow strain rate test (SSRT) in 3.5 wt. % NaCl solution. Optical micrographs of the corroded surfaces of polarised samples showed general corrosion, extensive pitting and intergranular corrosion as well. Further, potentiodynamic cyclic polarization curves displayed wide hysteresis loop indicating that the alloy tempers are susceptible to pit growth damage. Attempts have been made to explain the variation of observed electrochemical and SCC behaviour of the alloy tempers and the electrolyte conditions with the help of microstructural features.

Keywords: AA 2014 and AA 2024 Al-C-Mg alloy, artificial ageing, potentiodynamic polarization, TEM micrographs, stress corrosion cracking (SCC)

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Authors: Prathama Guha Chaudhuri, Arunima Datta, Ashis Mukhopadhyay

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Background: Visualization (guided imagery) is a set of techniques which induce relaxation and help people create positive mental images in order to reduce stress.It is relatively inexpensive and can even be practised by bed bound people. Studies have shown visualization to be an effective tool to improve cancer patients’ anxiety, depression and quality of life. The common images used with cancer patients in the developed world are those involving the individual’s body and its strengths. Since breast cancer patients in India are more family oriented and often their main concerns are the stigma of having cancer and subsequent isolation of their families, including their children, we figured that positive images involving acceptance and integration within family and society would be more effective for them. Method: Data was collected from 119 breast cancer patients on chemotherapy willing to undergo psychotherapy, with no history of past psychiatric illness. Their baseline stress, anxiety, depression and quality of life were assessed using validated tools. The participants were then randomly divided into three groups: a) those who received visualization therapy with standard imageries involving the body and its strengths (sVT), b) those who received visualization therapy using indigenous family oriented imageries (mVT) and c) a control group who received supportive therapy. There were six sessions spread over two months for each group. The psychological outcome variables were measured post intervention. Appropriate statistical analyses were done. Results:Both forms of visualization therapy were more effective than supportive therapy alone in reducing patients’ depression, anxiety and quality of life.Modified VT proved to be significantly more effective in improving patients’ anxiety and quality of life. Conclusion: Visualization is a valuable therapeutic option for reduction of psychological distress and improving quality of life of breast cancer patients.In order to be more effective, the images used need to be modified according to the sociocultural background and individual needs of the patients.

Keywords: breast cancer, visualization therapy, quality of life, anxiety, depression

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Authors: T. D. Ibragimov, A. R. Imamaliyev, G. M. Bayramov

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The polymer network liquid crystals based on the liquid crystals Н37 and 5CB with polymethylvinilpirydine (PMVP) and polyethylene glycol (PEG) have been developed. Mesogene substance 4-n-heptyoxibenzoic acid (HOBA) is served for stabilization of obtaining composites. Kinetics of network formation is investigated by methods of polarization microscopy and integrated small-angle scattering. It is shown that gel-like states of the composite H-37 + PMVP + HOBA and 5CB+PEG+HOBA are formed at polymer concentration above 7 % and 9 %, correspondingly. At slow cooling, the system separates into a liquid crystal –rich phase and a liquid crystal-poor phase. At this case, transition of these phases in the H-37 + PMVP + HOBA (87 % + 12 % + 1 %) composite to an anisotropic state occurs at 49 оС and и 41 оС, accordingly, while the composite 5CB+PEG+HOBA (85% +13 % +2%) passes to anisotropic state at 36 оС corresponding to the isotropic-nematic transition of pure 5CB. The basic electro-optic parameters of the obtained composites are determined at room temperature. It is shown that the threshold voltage of the composite H-37 + PMVP + HOBA increase in comparison with pure H-37 and, accordingly, there is a shift of voltage dependence of rise times to the high voltage region. The contrast ratio worsens while decay time improves in comparison with the pure liquid crystal at all applied voltage. The switching times of the composite 5CB + PEG + HOBA (85% +13 % +2%) show anomalous behavior connected with incompleteness of the transition to an anisotropic state. Experimental results are explained by phase separation of the system, diminution of a working area of electro-optical effects and influence of areas with the high polymer concentration on areas with their low concentration.

Keywords: liquid crystals, polymers, small-angle scattering, optical properties

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Authors: Teguh Endah Saraswati, Kusumandari Kusumandari, Candra Purnawan, Annisa Dinan Ghaisani, Aufara Mahayum

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The present study aims to investigate the degradation of methylene blue (MB) using TiO₂-carbon (TiO₂-C) photocatalyst combined with dielectric discharge (DBD) plasma. The carbon materials used in the photocatalyst were activated carbon and graphite. The thin layer of TiO₂-C photocatalyst was prepared by ball milling method which was then deposited on the plastic sheet. The characteristic of TiO₂-C thin layer was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) spectroscopy, and UV-Vis diffuse reflectance spectrophotometer. The XRD diffractogram patterns of TiO₂-G thin layer in various weight compositions of 50:1, 50:3, and 50:5 show the 2θ peaks found around 25° and 27° are the main characteristic of TiO₂ and carbon. SEM analysis shows spherical and regular morphology of the photocatalyst. Analysis using UV-Vis diffuse reflectance shows TiO₂-C has narrower band gap energy. The DBD plasma reactor was generated using two electrodes of Cu tape connected with stainless steel mesh and Fe wire separated by a glass dielectric insulator, supplied by a high voltage 5 kV with an air flow rate of 1 L/min. The optimization of the weight composition of TiO₂-C thin layer was studied based on the highest reduction of the MB concentration achieved, examined by UV-Vis spectrophotometer. The changes in pH values and color of MB indicated the success of MB degradation. Moreover, the degradation efficiency of MB was also studied in various higher concentrations of 50, 100, 200, 300 ppm treated for 0, 2, 4, 6, 8, 10 min. The degradation efficiency of MB treated in combination system of photocatalysis and DBD plasma reached more than 99% in 6 min, in which the greater concentration of methylene blue dye, the lower degradation rate of methylene blue dye would be achieved.

Keywords: activated carbon, DBD plasma, graphite, methylene blue, photocatalysis

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Authors: Olga Tkacheva, Pavel Arkhipov, Alexey Rudenko, Yurii Zaikov

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The aluminum electrolysis process in the conventional cryolite-alumina electrolyte with cryolite ratio of 2.7 was carried out at an initial temperature of 970 °C and the anode current density of 0.5 A/cm² in a 15A lab-scale cell in order to study the formation of the side ledge during electrolysis and the alumina distribution between electrolyte and side ledge. The alumina contained 35.97% α-phase and 64.03% γ-phase with the particles size in the range of 10-120 μm. The cryolite ratio and the alumina concentration were determined in molten electrolyte during electrolysis and in frozen bath after electrolysis. The side ledge in the electrolysis cell was formed only by the 13^th hour of electrolysis. With a slight temperature decrease a significant increase in the side ledge thickness was observed. The basic components of the side ledge obtained by the XRD phase analysis were Na₃AlF₆, Na₅Al₃F₁₄, Al₂O₃, and NaF^.5CaF₂^.AlF₃. As in the industrial cell, the increased alumina concentration in the side ledge formed on the cell walls and at the ledge-electrolyte-aluminum three-phase boundary during aluminum electrolysis in the lab cell was found (FTP No 05.604.21.0239, IN RFMEFI60419X0239).

Keywords: alumina distribution, aluminum electrolyzer, cryolie-alumina electrolyte, side ledge

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Authors: May Fadheel Estephan, Richard Perks

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Context: Cancer is a serious health concern that affects millions of people worldwide. Early detection and treatment are essential for improving patient outcomes. However, current methods for cancer detection have limitations, such as low sensitivity and specificity. Research Aim: The aim of this study was to develop an optical sensor for cancer detection using elastic light scattering spectroscopy (ELSS). ELSS is a noninvasive optical technique that can be used to characterize the size and concentration of particles in a solution. Methodology: An optical probe was fabricated with a 100-μm-diameter core and a 132-μm centre-to-centre separation. The probe was used to measure the ELSS spectra of polystyrene spheres with diameters of 2, 0.8, and 0.413 μm. The spectra were then analysed to determine the size and concentration of the spheres. Findings: The results showed that the optical probe was able to differentiate between the three different sizes of polystyrene spheres. The probe was also able to detect the presence of polystyrene spheres in suspension concentrations as low as 0.01%. Theoretical Importance: The results of this study demonstrate the potential of ELSS for cancer detection. ELSS is a noninvasive technique that can be used to characterize the size and concentration of cells in a tissue sample. This information can be used to identify cancer cells and assess the stage of the disease. Data Collection: The data for this study were collected by measuring the ELSS spectra of polystyrene spheres with different diameters. The spectra were collected using a spectrometer and a computer. Analysis Procedures: The ELSS spectra were analysed using a software program to determine the size and concentration of the spheres. The software program used a mathematical algorithm to fit the spectra to a theoretical model. Question Addressed: The question addressed by this study was whether ELSS could be used to detect cancer cells. The results of the study showed that ELSS could be used to differentiate between different sizes of cells, suggesting that it could be used to detect cancer cells. Conclusion: The findings of this research show the utility of ELSS in the early identification of cancer. ELSS is a noninvasive method for characterizing the number and size of cells in a tissue sample. To determine cancer cells and determine the disease's stage, this information can be employed. Further research is needed to evaluate the clinical performance of ELSS for cancer detection.

Keywords: elastic light scattering spectroscopy, polystyrene spheres in suspension, optical probe, fibre optics

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Authors: Rabia Almas

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Today’s world is demanding natural and biological colorants on priority bases as an alternative to toxic and unsustainable synthetic dyes. Sustainable natural colors from plants and/or living organisms such as bacteria's and fungi attracted the world research scholars and textile industries recently due to the excitement and opportunities they covered. So, in the present study, natural colors from food waste, such as orange peels and peanuts, were extracted and applied to cotton fabric. The dyeing recipes were optimized in terms of dye concentration, processing temperature and time for higher color strength. The characterization of the dyes and fabric, such as Fourier transform infrared spectroscopy, Scanning Electron Microscopy, and fastness properties were measured for the identification of the chemical groups involved for a better understanding of the dyeing behavior. The results revealed that proper mordanting and concentration of dye on cotton fabric could give high color strength and good fastness to wash and light and these natural dyes can be used as an alternative to synthetic toxic colorants.

Keywords: textile, textile dyes, natural dyes, bio colors

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