Search results for: membrane resistance

Authors: Sri Rahayu, M. Dwi Susan, Aris Soewondo, W. M. Agung Pramana

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Semen is an organic fluid (seminal plasma) that contain spermatozoa. Proteins are one of the major seminal plasma components that modulate sperm functionality, influence sperm capacitation and maintaining the stability of the membrane. Semen freezing is a procedure to preserve sperm cells. The process causes decrease in sperm viability due to temperature shock and oxidation stress. Oxidation stress is a disturbance on phosphorylation that increases ROS concentration, and it produces lipid peroxide in spermatozoa membrane resulted in high MDA (malondialdehyde) concentration. The objective of this study was to examine the effect of freezing on protein and MDA profile of bovine sperm cell and seminal plasma after freezing. Protein and MDA of sperm cell and seminal plasma were isolated from 10 sample. Protein profiles was analyzed by SDS PAGE with separating gel 12,5 %. The concentration of MDA was measured by spectrophotometer. The results of the research indicated that freezing of semen cause lost of the seminal plasma proteins with molecular with 20, 10, and 9 kDa. In addition, the result research showed that protein of the sperm (26, 10, 9, 7, and 6 kDa) had been lost. There were difference MDA concentration of seminal plasma and sperm cell were increase after freezing. MDA concentration of seminal plasma before and after freezing were 2.2 and 2.4 nmol, respectively. MDA concentration of sperm cell before and after freezing were 1,5 and 1.8 nmol, respectively. In conclusion, there were differences protein profiles of spermatozoa before and after semen freezing and freezing cause increasing of the MDA concentration.

Keywords: MDA, semen freezing, SDS PAGE, protein profile

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Authors: Atsebaha Gebrekidan Kahsay, Tsehaye Asmelash, Enquebaher Kassaye

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Background: Salmonella remains a global public health problem with a significant burden in sub-Saharan African countries. Human restricted cause of typhoid and paratyphoid fever are S. Typhi and S. Paratyphi, whereas S. Enteritidis and S. Typhimurium is the causative agent of invasive nontyphoidal diseases among humans and animals are their reservoir. The antibiotic resistance of Salmonella is another public health threat around the globe. To come up with full information about human and animal salmonellosis, we made a systematic review of the prevalence, serotypes, and antibiotic resistance of Salmonella in Ethiopia. Methods: This systematic review used Google Scholar and PubMed search engines to search articles from Ethiopia that were published in English in peer-reviewed international journals from 2010 to 2022. We used keywords to identify the intended research articles and used a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the inclusion and exclusion criteria. Frequencies and percentages were analyzed using Microsoft Excel. Results: Two hundred seven published articles were searched, and 43 were selected for a systematic review, human (28) and animals (15). The prevalence of Salmonella in humans and animals was 434 (5.2%) and 641(10.1%), respectively. Fourteen serotypes were identified from animals, and S. Typhimurium was among the top five. Among the ciprofloxacin-resistant isolates in human studies, 16.7% was the highest, whereas, for ceftriaxone, 100% resistance was reported. Conclusions: The prevalence of Salmonella among diarrheic patients and food handlers (5.2%) was lower than the prevalence in food animals (10.1%). We did not find serotypes of Salmonella in human studies, although fourteen serotypes were included in food-animal studies, and S. Typhimurium was among the top five. Salmonella species from some human studies revealed a non-susceptibility to ceftriaxone. We recommend further study about invasive nontyphoidal Salmonella and predisposing factors among humans and animals in Ethiopia.

Keywords: antibiotic resistance, prevalence, systematic review, serotypes, Salmonella, Ethiopia

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Authors: Jianzheng Wei, Duo Zhen, Zhihan Yang, Huifeng Tan

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The deployable descent technology is a lightweight entry method using an inflatable heat shield. The heatshield consists of a pressurized core which is covered by different layers of thermal insulation and flexible ablative materials in order to protect against the thermal loads. In this paper, both aluminum and silicon-aluminum aerogels were prepared by freeze-drying method. The latter material has bigger specific surface area and nano-scale pores. Mullite fibers are used as the reinforcing fibers to prepare the aerogel matrix to improve composite flexibility. The flexible composite materials were performed as an insulation layer to an underlying aramid fabric by a thermal shock test at a heat flux density of 120 kW/m² and uniaxial tensile test. These results show that the aramid fabric with untreated mullite fibers as the thermal protective layer is completely carbonized at the heat of about 60 s. The aramid fabric as a thermal resistance layer of the composite material still has good mechanical properties at the same heat condition.

Keywords: aerogel, aramid fabric, flexibility, thermal resistance

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Authors: Wilson Handoko, Farshid Pahlevani, Isha Singla, Himanish Kumar, Veena Sahajwalla

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Aluminium bronze alloys are well known for their superior abrasion, tensile strength and non-magnetic properties, due to the co-presence of iron (Fe) and aluminium (Al) as alloying elements and have been commonly used in many industrial applications. However, continuous exposure to the marine environment will accelerate the risk of a tendency to Al bronze alloys parts failures. Although a higher level of corrosion resistance properties can be achieved by modifying its elemental composition, it will come at a price through the complex manufacturing process and increases the risk of reducing the ductility of Al bronze alloy. In this research, the use of ironmaking slag and waste plastic as the input source for surface modification of Al bronze alloy was implemented. Microstructural analysis conducted using polarised light microscopy and scanning electron microscopy (SEM) that is equipped with energy dispersive spectroscopy (EDS). An electrochemical corrosion test was carried out through Tafel polarisation method and calculation of protection efficiency against the base-material was determined. Results have indicated that uniform modified surface which is as the result of selective diffusion process, has enhanced corrosion resistance properties up to 12.67%. This approach has opened a new opportunity to access various industrial utilisations in commercial scale through minimising the dependency on natural resources by transforming waste sources into the protective coating in environmentally friendly and cost-effective ways.

Keywords: aluminium bronze, waste-based surface modification, tafel polarisation, corrosion resistance

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Authors: Xin Li, Yan-Rong Guo, Jin-Fang Lin, Yi Feng, Håkan Billig, Ruijin Shao

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Background: Young women with polycystic ovary syndrome (PCOS) have a high risk of developing endometrial carcinoma. There is a need for the development of new medical therapies that can reduce the need for surgical intervention so as to preserve the fertility of these patients. The aim of the study was to describe and discuss cases of PCOS and insulin resistance (IR) women with early endometrial carcinoma while being co-treated with Diane-35 and metformin. Methods: Five PCOS-IR women who were scheduled for diagnosis and therapy for early endometrial carcinoma were recruited. The hospital records and endometrial pathology reports were reviewed. All patients were co-treated with Diane-35 and metformin for 6 months to reverse the endometrial carcinoma and preserve their fertility. Before, during, and after treatment, endometrial biopsies and blood samples were obtained and oral glucose tolerance tests were performed. Endometrial pathology was evaluated. Body weight (BW), body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), sex hormone-binding globulin (SHBG), free androgen index (FAI), insulin area under curve (IAUC), and homeostasis model assessment of insulin resistance (HOMA-IR) were determined. Results: Clinical stage 1a, low grade endometrial carcinoma was confirmed before treatment. After 6 months of co-treatment, all patients showed normal epithelia. No evidence of atypical hyperplasia or endometrial carcinoma was found. Co-treatment resulted in significant decreases in BW, BMI, TT, FAI, IAUC, and HOMA-IR in parallel with a significant increase in SHBG. There were no differences in the FSH and LH levels after co-treatment. Conclusions: Combined treatment with Diane-35 and metformin has the potential to revert the endometrial carcinoma into normal endometrial cells in PCOS-IR women. The cellular and molecular mechanisms behind this effect merit further investigation.

Keywords: PCOS, progesterone resistance, insulin resistance, steroid hormone receptors, endometrial carcinoma

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Authors: Nehir Nebioglu

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Chemotherapy is widely used for the treatment of cancer. Doxorubicin is an anti-cancer chemotherapy drug that is classified as an anthracycline antibiotic. Antitumor antibiotics consist of natural products produced by species of the soil fungus Streptomyces. These drugs act in multiple phases of the cell cycle and are known cell-cycle specific. Although DOX is a precious clinical antineoplastic agent, resistance is also a problem that limits its utility besides cardiotoxicity problem. The drug resistance of cancer cells results from multiple factors including individual variation, genetic heterogeneity within a tumor, and cellular evolution. The mechanism of resistance is thought to involve, in particular, ABCB1 (MDR1, Pgp) and ABCC1 (MRP1) as well as other transporters. Several studies on DOX-resistant cell lines have shown that resistance can be overcome by an inhibition of ABCB1, ABCC1, and ABCC2. This study attempts to understand the effects of different concentration levels of glucose treatment and starvation on the proliferation of Doxorubicin resistant cancer cells lines. To understand the effect of starvation, K562/Dox and K562 cell lines were treated with 0, 5 nM, 50 nM, 500 nM, 5 uM and 50 uM Dox concentrations in both starvation and normal medium conditions. In addition to this, to interpret the effect of glucose treatment, different concentrations (0, 1 mM, 5 mM, 25 mM) of glucose were applied to Dox-treated (with 0, 5 nM, 50 nM, 500 nM, 5 uM and 50 uM) K562/Dox and K652 cell lines. All results show significant decreasing in the cell count of K562/Dox, when cells were starved. However, while proliferation of K562/Dox lines decrease is associated with the increasingly applied Dox concentration, K562/Dox starved ones remain at the same proliferation level. Thus, the results imply that an amount of K562/Dox lines gain starvation resistance and remain resistant. Furthermore, for K562/Dox, there is no clear effect of glucose treatment in terms of cell proliferation. In the presence of a moderate level of glucose (5 mM), proliferation increases compared to other concentration of glucose for each different Dox application. On the other hand, a significant increase in cell proliferation in moderate level of glucose is only observed in 5 uM Dox concentration. The moderate concentration level of Dox can be examined in further studies. For the high amount of glucose (25 mM), cell proliferation levels are lower than moderate glucose application. The reason could be high amount of glucose may not be absorbable by cells. Also, in the presence of low amount of glucose, proliferation is decreasing in an orderly manner of increase in Dox concentration. This situation can be explained by the glucose depletion -Warburg effect- in the literature.

Keywords: drug resistance, cancer cells, chemotherapy, doxorubicin

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Authors: Goodarzvand Fatemeh, Soori Rahman, Effatpanah Mohammad, Ajbarnejad Ali

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Attention deficit hyperactivity disorder (ADHD) is characterized by a pervasive pattern of developmentally inappropriate inattentive, impulsive and hyperactive behaviors that typically begin during the preschool ages and often persist into adulthood. This disorder is related to autism and schizophrenia and other psychological disorders and clinical conditions such as insulin resistance and they may operate through common pathways, and treatments used exclusively for one of these conditions may prove beneficial for the others. While ADHD is not fully understood as developmental disorder with an etiopathogeny, but studies show that core symptom of disorder was associated with and increased by the interleukins IL-13, where relation of IL-13 with inattention was notable. Regular exercise improves functions associated with attention deficit hyperactivity disorder (ADHD). However, the impact of exercise on cytokines associated with the disease activity remains relatively unexplored. The aim of this study was to examine the effects of 6 weeks high intensity by intervals training (HIIT) on IL-13 levels and insulin resistance in boys with ADHD. Twenty eight boys with ADHD disease in a range of 12-18 year of old participated in this study as the subject. Subjects were divided into control group (n=10) and training group (n=18) randomly. The training group performed progressive HIIT program, 3 days a week for 6 weeks. The control group was in absolute rest at the same time. The results showed that after six weeks of HIIT, IL-13 decreased in the exercise group and these changes achieved (p= 0.002) statistical significance (p < 0.005). The results suggest HIIT with specific intensity and duration utilized in this study had not significant effect on insulin resistance levels in female patients with ADHD (p=0.39), while the difference in the average control and case group was decreased.

Keywords: attention deficit hyperactivity disorder, interleukin 13, insulin resistance, high intensity by intervals training

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Authors: Robert Pečenko, Karin Tomažič, Igor Planinc, Sabina Huč, Tomaž Hozjan

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Timber is favourable structural material due to high strength to weight ratio, recycling possibilities, and green credentials. Despite being flammable material, it has relatively high fire resistance. Everyday engineering practice around the word is based on an outdated design of timber structures considering standard fire exposure, while modern principles of performance-based design enable use of advanced non-standard fire curves. In Europe, standard for fire design of timber structures EN 1995-1-2 (Eurocode 5) gives two methods, reduced material properties method and reduced cross-section method. In the latter, fire resistance of structural elements depends on the effective cross-section that is a residual cross-section of uncharred timber reduced additionally by so called zero strength layer. In case of standard fire exposure, Eurocode 5 gives a fixed value of zero strength layer, i.e. 7 mm, while for non-standard parametric fires no additional comments or recommendations for zero strength layer are given. Thus designers often implement adopted 7 mm rule also for parametric fire exposure. Since the latest scientific evidence suggests that proposed value of zero strength layer can be on unsafe side for standard fire exposure, its use in the case of a parametric fire is also highly questionable and more numerical and experimental research in this field is needed. Therefore, the purpose of the presented study is to use advanced calculation methods to investigate the thickness of zero strength layer and parametric charring rates used in effective cross-section method in case of parametric fire. Parametric studies are carried out on a simple solid timber beam that is exposed to a larger number of parametric fire curves Zero strength layer and charring rates are determined based on the numerical simulations which are performed by the recently developed advanced two step computational model. The first step comprises of hygro-thermal model which predicts the temperature, moisture and char depth development and takes into account different initial moisture states of timber. In the second step, the response of timber beam simultaneously exposed to mechanical and fire load is determined. The mechanical model is based on the Reissner’s kinematically exact beam model and accounts for the membrane, shear and flexural deformations of the beam. Further on, material non-linear and temperature dependent behaviour is considered. In the two step model, the char front temperature is, according to Eurocode 5, assumed to have a fixed temperature of around 300°C. Based on performed study and observations, improved levels of charring rates and new thickness of zero strength layer in case of parametric fires are determined. Thus, the reduced cross section method is substantially improved to offer practical recommendations for designing fire resistance of timber structures. Furthermore, correlations between zero strength layer thickness and key input parameters of the parametric fire curve (for instance, opening factor, fire load, etc.) are given, representing a guideline for a more detailed numerical and also experimental research in the future.

Keywords: advanced numerical modelling, parametric fire exposure, timber structures, zero strength layer

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Authors: Abdollah Jamshidi, Tayebeh Zeinali, Mehrnaz Rad, Jamshid Razmyar

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Listeria infections occur worldwide in variety of animals and man. Listeriae are widely distributed in nature. The organism has been isolated from the feces of humans and several animals, different soils, plants, aquatic environments and food of animal and vegetable origin. Listeria monocytogenes is recognized as important food-borne pathogens due to its high mortality rate. This organism is able to growth at refrigeration temperature, and high osmotic pressure. Poultry can become contaminated environmentally or through healthy carrier birds. In recent decades, prophylactic use of antimicrobial agents may be lead to emergence of antibiotic resistant organisms, which can be transmitted to human through consumption of contaminated foods. In this study, from 200 fresh chicken carcasses samples which were collected randomly from different supermarkets and butcheries, 80 samples were detected as contaminate with Listeria spp. and 19% of the isolates identified as Listeria monocytogene using multiplex PCR assay. Conventional methods were used to differentiate other species of the listeria genus. The results showed the most prevalent isolates as L. monocytogenes (48.75%). Other isolates were detected as Listeria innocua (28.75%), Listeria murrayi (20%), Listeria grayi (3.75%) and Listeria welshimeri (2.5%).The Majority of the isolates had multidrug resistance to commonly used antibiotics. Most of them were resistant to erythromycin (50%), followed by Tetracycline (44.44%), Clindamycin (41.66%), and Trimethoprim (25%). Some of them showed resistance to chloramphenicol (17.65%). The results indicate the resistance of the isolates to antimicrobials commonly used to treat human listeriosis, which could be a potential health hazard for consumers.

Keywords: listeria species, L. monocytogenes, antibiotic resistance, chicken carcass

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Authors: Ali Ghorbanipour

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The aim of this study is to investigate the drug resistance pattern and the value of the MIC (minimum inhibitory concentration)method to reduce the impact of infectious diseases and the slow development of resistance. Method: The study was conducted on clinical specimens collected between 2018 to 2021. identification of isolates and antibiotic susceptibility testing were performed using conventional biochemical tests. Antibiotic resistance was determined using kibry-Bauer disk diffusion and MIC by E-test methods comparative with microdilution plate elisa method. Results were interpreted according to CLSI. Results: Out of 249600 different clinical specimens, 18720 different pathogenic bacteria by overall detection ratio 7.7% were detected. Among pathogen bacterial were Gram negative bacteria (70%,n=13000) and Gram positive bacteria(30%,n=5720).Medically relevant gram-negative bacteria include a multitude of species such as E.coli , Klebsiella .spp , Pseudomonas .aeroginosa , Acinetobacter .spp , Enterobacterspp ,and gram positive bacteria Staphylococcus.spp , Enterococcus .spp , Streptococcus .spp was isolated . Conclusion: Our results highlighted that the resistance ratio among Gram Negative bacteria and Gram positive bacteria with different infection is high it suggest constant screening and follow-up programs for the detection of antibiotic resistance and the value of MIC drug susceptibility reporting that provide a new way to the usage of resistant antibiotic in combination with other antibiotics or accurate weight of antibiotics that inhibit or kill bacteria. Evaluation of wrong medication in the expansion of resistance and side effects of over usage antibiotics are goals. Ali ghorbanipour presently working as a supervision at the microbiology department of Massoud medical laboratory. Iran. Earlier, he worked as head department of pulmonary infection in firoozgarhospital, Iran. He received master degree in 2012 from Fergusson College. His research prime objective is a biologic wound dressing .to his credit, he has Published10 articles in various international congresses by presenting posters.

Keywords: antimicrobial profile, MIC & MBC Method, microplate antimicrobial assay, E-test

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Authors: Frida Carrillo Morales, Maria Maricela Carrasco Yépez, Saúl Rojas Hernández

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Naegleria fowleri is the causative agent of primary amebic meningoencephalitis, this disease is acute and fulminant that affects humans. It has been reported that despite the existence of therapeutic options against this disease, its mortality rate is 97%. Therefore, the need arises to have vaccines that confer protection against this disease and, in addition to developing adjuvants to enhance the immune response. In this regard, in our work group, we obtained a peptide designed from the membrane protein MP2CL5 of Naegleria fowleri called Smp145 that was shown to be immunogenic; however, it would be of great importance to enhance its immunological response, being able to co-administer it with a non-toxic adjuvant. Therefore, the objective of this work was to carry out the bioinformatic design of a peptide of the Naegleria fowleri membrane protein MP2CL5 conjugated with a non-toxic modified adjuvant from the native A1 structure of Cholera Toxin. For which different bioinformatics tools were used to obtain a model with a modification in amino acid 61 of the A1 subunit of the CT (CTA1), to which the Smp145 peptide was added and both molecules were joined with a 13-glycine linker. As for the results obtained, the modification in CTA1 bound to the peptide produces a reduction in the toxicity of the molecule in in silico experiments, likewise, the prediction in the binding of Smp145 to the receptor of B cells suggests that the molecule is directed in specifically to the BCR receptor, decreasing its native enzymatic activity. The stereochemical evaluation showed that the generated model has a high number of adequately predicted residues. In the ERRAT test, the confidence with which it is possible to reject regions that exceed the error values was evaluated, in the generated model, a high score was obtained, which determines that the model has a good structural resolution. Therefore, the design of the conjugated peptide in this work will allow us to proceed with its chemical synthesis and subsequently be able to use it in the mouse meningitis protection model caused by N. fowleri.

Keywords: immunology, vaccines, pathogens, infectious disease

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Authors: Tahani Farah, Hanène Souli, Jean-Marie Fleureau, Guillaume Kermouche, Jean-Jacques Fry, Benjamin Girard, Denis Aelbrecht

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In this work, the bio-clogging of two soils with different granulometries is presented. The durability of the clogging is also studied under cycles of hydraulic head and under cycles of desaturation- restauration. The studied materials present continuous grain size distributions. The first one corresponding to the "material 1", presents grain sizes between 0.4 and 4 mm. The second material called "material 2" is composed of grains with size varying between 1 and 10 mm. The results show that clogging occurs very quickly after the injection of nutrition and an outlet flow near to 0 is observed. The critical hydraulic head is equal to 0.76 for "material 1", and 0.076 for "material 2". The durability tests show a good resistance to unclogging under cycles of hydraulic head and desaturation-restauration for the "material 1". Indeed, the flow after the cycles is very low. In contrast, "material 2", shows a very bad resistance, especially under the hydraulic head cycles. The resistance under the cycles of desaturation-resaturation is better but an important increase of the flow is observed. The difference of behavior is due to the granulometry of the materials. Indeed, the large grain size contributes to the reduction of the efficiency of the bio-clogging treatment in this material.

Keywords: bio-clogging, granulometry, permeability, nutrition

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Authors: Jayanwita Sarkar, Usha Chakraborty, Bishwanath Chakraborty

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Plants are constantly interacting with various abiotic and biotic stresses. In changing climate scenario plants are continuously modifying physiological processes to adapt to changing environmental conditions which profoundly affect plant-pathogen interactions. Spot blotch in wheat is a fast-rising disease in the warmer plains of South Asia where the rise in minimum average temperature over most of the year already affecting wheat production. Hence, the study was undertaken to explore the role of elevated temperature in spot blotch disease development and modulation of antioxidative responses by plant growth promoting rhizobacteria (PGPR) for biocontrol of spot blotch at high temperature. Elevated temperature significantly increases the susceptibility of wheat plants to spot blotch causing pathogen Bipolaris sorokiniana. Two PGPR Bacillus safensis (W10) and Ochrobactrum pseudogrignonense (IP8) isolated from wheat (Triticum aestivum L.) and blady grass (Imperata cylindrical L.) rhizophere respectively, showing in vitro antagonistic activity against Bipolaris sorokiniana were tested for growth promotion and induction of resistance against spot blotch in wheat. GC-MS analysis showed that Bacillus safensis (W10) and Ochrobactrum pseudogrignonense (IP8) produced antifungal and antimicrobial compounds in culture. Seed priming with these two bacteria significantly increase growth, modulate antioxidative signaling and induce resistance and eventually reduce disease incidence in wheat plants at optimum as well as elevated temperature which was further confirmed by indirect immunofluorescence assay using polyclonal antibody raised against Bipolaris sorokiniana. Application of the PGPR led to enhancement in activities of plant defense enzymes- phenylalanine ammonia lyase, peroxidase, chitinase and β-1,3 glucanase in infected leaves. Immunolocalization of chitinase and β-1,3 glucanase in PGPR primed and pathogen inoculated leaf tissue was further confirmed by transmission electron microscopy using PAb of chitinase, β-1,3 glucanase and gold labelled conjugates. Activity of ascorbate-glutathione redox cycle related enzymes such as ascorbate peroxidase, superoxide dismutase and glutathione reductase along with antioxidants such as carotenoids, glutathione and ascorbate and osmolytes like proline and glycine betain accumulation were also increased during disease development in PGPR primed plant in comparison to unprimed plants at high temperature. Real-time PCR analysis revealed enhanced expression of defense genes- chalcone synthase and phenyl alanineammonia lyase. Over expression of heat shock proteins like HSP 70, small HSP 26.3 and heat shock factor HsfA3 in PGPR primed plants effectively protect plants against spot blotch infection at elevated temperature as compared with control plants. Our results revealed dynamic biochemical cross talk between elevated temperature and spot blotch disease development and furthermore highlight PGPR mediated array of antioxidative and molecular alterations responsible for induction of resistance against spot blotch disease at elevated temperature which seems to be associated with up-regulation of defense genes, heat shock proteins and heat shock factors, less ROS production, membrane damage, increased expression of redox enzymes and accumulation of osmolytes and antioxidants.

Keywords: antioxidative enzymes, defense enzymes, elevated temperature, heat shock proteins, PGPR, Real-Time PCR, spot blotch, wheat

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Authors: M. Nakisa, A. Maimun, Yasser M. Ahmed, F. Behrouzi, A. Tarmizi

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The practical application of the Computational Fluid Dynamics (CFD), for predicting the flow pattern around Multipurpose Amphibious Vehicle (MAV) hull has made much progress over the last decade. Today, several of the CFD tools play an important role in the land and water going vehicle hull form design. CFD has been used for analysis of MAV hull resistance, sea-keeping, maneuvering and investigating its variation when changing the hull form due to varying its parameters, which represents a very important task in the principal and final design stages. Resistance analysis based on CFD (Computational Fluid Dynamics) simulation has become a decisive factor in the development of new, economically efficient and environmentally friendly hull forms. Three-dimensional finite volume method (FVM) based on Reynolds Averaged Navier-Stokes equations (RANS) has been used to simulate incompressible flow around three types of MAV hull bow models in steady-state condition. Finally, the flow structure and streamlines, friction and pressure resistance and velocity contours of each type of hull bow will be compared and discussed.

Keywords: RANS simulation, multipurpose amphibious vehicle, viscous flow structure, mechatronic

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Authors: Pinki Sharma, Himanshu Joshi

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Distillery spentwash contains high chemical oxygen demand (COD), biological oxygen demand (BOD), color, total dissolved solids (TDS) and other contaminants even after biological treatment. The effluent can’t be discharged as such in the surface water bodies or land without further treatment. Reverse osmosis (RO) treatment plants have been installed in many of the distilleries at tertiary level. But at most of the places these plants are not properly working due to high concentration of organic matter and other contaminants in biologically treated spentwash. To make the membrane treatment proven and reliable technology, proper pre-treatment is mandatory. In the present study, ultra-filtration (UF) as pre-treatment of RO at tertiary stage was performed. Operating parameters namely initial pH (pHo: 2–10), trans-membrane pressure (TMP: 4-20 bars) and temperature (T: 15- 43°C) used for conducting experiments with UF system. Experiments were optimized at different operating parameters in terms of COD, color, TDS and TOC removal by using response surface methodology (RSM) with central composite design. The results showed that removal of COD, color and TDS by 62%, 93.5% and 75.5%, with UF, respectively at optimized conditions with increased permeate flux from 17.5 l/m2/h (RO) to 38 l/m2/h (UF-RO). The performance of the RO system was greatly improved both in term of pollutant removal as well as water recovery.

Keywords: bio-digested distillery spentwash, reverse osmosis, response surface methodology, ultra-filtration

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Authors: A. Zarenezhad, A. Esfandiari, E. Zarenezhad, M. Mardkhoshnood

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The aim of this study was to investigate the ultra-structure of the photoreceptor layer of male rats under the effect of methanol intoxication and protective effect of silymarin against the methanol toxicity. Fifteen adult male rats were divided into three groups: Control group, Experimental group I (received 4g/kg methanol by intraperitoneal injection for five days), Experimental group II (received 4 g/kg methanol by intraperitoneal injection for five days and received 250 mg/kg silymarin orally for three months). At the end of the experiment, the eyes were removed; retina was separated near the optic disc and studied by transmission electron microscope. Results showed that the retina in the experimental group I exhibited loss of outer segments and disorganization in inner segment. Increased extra cellular space, disappearance of outer limiting membrane and pyknotic nuclei were seen in this group. But normal outer segment, organized inner segment and normal outer limiting membrane were obvious after treatment with silymarin in experimental group II. These findings show that methanol causes damage in the photoreceptor layer of the rat retina and silymarin can protect the damage to retina against the methanol intoxication.

Keywords: ultra-structure, photoreceptor layer, methanol intoxication, silymarin, rat

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Authors: Aminah Muchdar

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Efforts to increase soybean production have been pursued for years in Indonesia through the process of intensification and extensification. Increased production through intensification of increasing grain yield per hectare, among others includes the improvement of cultivation system such as the use of cultivars that have superior resistance to drought. Increased soybean production has been through the expansion of planting areas utilizing available idle dry land. However, one of the constraints faced in dryland agriculture was the limited water supply due to low intensity of rainfall that leads to low crop production. In order to ensure that soybeans are cultivated on dry land remains capable of high production, it is necessary to physiologically engineer the soybean with open stomata. The study was conducted in the greenhouse of Balai Penelitian Tanaman Serealia (BALITSEREAL) Maros, Sulawesi, Indonesia with a completely randomized block design h factorial pattern. The first factor was the water stress stadia while the second was the amount of sorbitol osmolit concentration application. Results indicated that there was an interaction between the plant height growth and number of leaves between the water clamping time and concentration of the osmolit sorbitol. The vegetative stage especially during flowering and pod formation was inhibited when the water was clamped, but by spraying osmolit sorbitol, soybean growth in terms of its height and number of leaves was enhanced. This study implies that the application of osmolit sorbitol may enhance the drought resistance of soybean growth. Future research suggested that more work should be done on the application of osmolit sorbital to other agriculture crops to increase their drought resistance in the drylands.

Keywords: DROUGHT, engineered physiology, osmolit sorbitol, soybean

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Authors: Ehsan Ahmadifar, Mohammad Ali Yousefi, Zahra Roohi

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In this study, the effects of different levels of Ergosan (control group (0), 2, 4 and 6 gr Ergosan per Kg diet) as a nutritional supplement were investigated on growth indices and stress in Zebrafish for 3 months. Larvae (4-day-old after hatching) were fed with experimental diet from the beginning of feeding until adult (adolescence) (average weight: 69.3 g, length: 5.1 cm). Different levels of Ergosan had no significant effect on rate survival (P < 0.05). The results showed that diet containing 6 gr Ergosan significantly caused the best FCR in Zebrafish (P < 0.05). By increasing the Ergosan diet, specific growth rate increased. Body weight gain and condition factor had significant differences (P < 0.05) as the highest and the lowest were observed in treatment 3 gr of Ergosan and control, respectively. The results showed that fish fed with experimental diet, had the highest resistance to environmental stresses compared to control, and the test temperature, oxygen, salinity and alkalinity samples containing 6 gr/kg, was significantly more resistance compared to the other treatments (P < 0.05). Overall, to achieve high resistance to environmental stress and increase final biomass using 6 gr/kg Ergosan in diet fish Zebrafish.

Keywords: Ergosan, stress, growth performance, Danio rerio

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Authors: M. Venegas, M. De Vega, N. García-Hernando

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Absorption cooling chillers have received growing attention over the past few decades as they allow the use of low-grade heat to produce the cooling effect. The combination of this technology with solar thermal energy in the summer period can reduce the electricity consumption peak due to air-conditioning. One of the main components, the absorber, is designed for simultaneous heat and mass transfer. Usually, shell and tubes heat exchangers are used, which are large and heavy. Cooling water from a cooling tower is conventionally used to extract the heat released during the absorption and condensation processes. These are clear inconvenient for the generalization of the absorption technology use, limiting its benefits in the contribution to the reduction in CO2 emissions, particularly for the H2O-LiBr solution which can work with low heat temperature sources as provided by solar panels. In the present work a promising new technology is under study, consisting in the use of membrane contactors in adiabatic microchannel mass exchangers. The configuration here proposed consists in one or several modules (depending on the cooling capacity of the chiller) that contain two vapour channels, separated from the solution by adjacent microporous membranes. The solution is confined in rectangular microchannels. A plastic or synthetic wall separates the solution channels between them. The solution entering the absorber is previously subcooled using ambient air. In this way, the need for a cooling tower is avoided. A model of the configuration proposed is developed based on mass and energy balances and some correlations were selected to predict the heat and mass transfer coefficients. The concentration and temperatures along the channels cannot be explicitly determined from the set of equations obtained. For this reason, the equations were implemented in a computer code using Engineering Equation Solver software, EES™. With the aim of minimizing the absorber volume to reduce the size of absorption cooling chillers, the ratio between the cooling power of the chiller and the absorber volume (R) is calculated. Its variation is shown along the solution channels, allowing its optimization for selected operating conditions. For the case considered the solution channel length is recommended to be lower than 3 cm. Maximum values of R obtained in this work are higher than the ones found in optimized horizontal falling film absorbers using the same solution. Results obtained also show the variation of R and the chiller efficiency (COP) for different ambient temperatures and desorption temperatures typically obtained using flat plate solar collectors. The configuration proposed of adiabatic membrane-based absorber using ambient air to subcool the solution is a good technology to reduce the size of the absorption chillers, allowing the use of low temperature solar heat and avoiding the need for cooling towers.

Keywords: adiabatic absorption, air-cooled, membrane, solar thermal energy

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Authors: Minu Bharati, Priyanka Rai, Satarupa Dutta, Dhiraj Saha

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Culex quinquefasciatus Say, is a mosquito of immense public health concern due to its role in transmission of filariasis, which is an endemic disease in 20 states and union territories of India, putting about 600 million people at the risk of infection. The main strategies to control filaria in India include anti-larval measures in urban areas, Indoor Residual Spray (IRS) in rural areas and mass diethylcarbamazine citrate (DEC) administration. Larval destruction measures and IRS are done with the use of insecticides. In this study, Susceptibility/ Resistance to insecticides were assessed in Culex quinquefasciatus mosquitoes collected from eight densely populated areas of Siliguri subdivision, which has a high rate of filarial infection. To unveil the insecticide susceptibility status of Culex quinquefasciatus, bioassays were performed on field-caught mosquitoes against two major groups of insecticides, i.e. Synthetic Pyrethroids (SPs): 0.05% deltamethrin and 0.05% lambda-cyhalothrin and Organophosphates (OPs): 5% malathion and temephos using World Health Organisation (WHO) discriminating doses. The knockdown rates and knockdown times (KDT50) were also noted against deltamethrin, lambda-cyhalothrin and malathion. Also, activities of major detoxifying enzymes, i.e. α-carboxylesterases, β-carboxylesterases and cytochrome P450 (CYP450) monooxygenases were determined to find the involvement of biochemical mechanisms in resistance phenomenon (if any). The results obtained showed that, majority of the mosquito populations were moderately to severely resistant against both the SPs and one OP, i.e. temephos. Whereas, most of the populations showed 100% susceptibility to malathion. The knockdown rates and KDT50 in response to above-mentioned insecticides showed significant variation among different populations. Variability in activities of carboxylesterases and CYP450 monooxygenases were also observed with hints of their involvement in contribution towards insecticide resistance in some of the tested populations. It may be concluded that, Culex quinquefasciatus has started developing resistance against deltamethrin, lambda-cyhalothrin and temephos in Siliguri subdivision. Malathion seems to hold the greatest potentiality for control of these mosquitoes in this area as revealed through this study. Adoption of Integrated mosquito management (IMM) strategy should be the prime objective of the concerned authorities to delimit the insecticide resistance phenomenon and filariasis infections.

Keywords: Culex quinquefasciatus, detoxifying enzymes, insecticide resistance, knockdown rate

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Authors: Mohammed Mamdouh Mohammed, Ali Zain Elabdeen Heikal, Hassan Mahdy, Sherif El-Badawy

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The main purpose of this research is to assess the effectiveness of the Cold In-Place Recycling (CIR) technique in asphalt maintenance by analyzing performance outcomes. To achieve this, fifteen CIR mixtures were prepared using slow-setting emulsified asphalt as the recycling agent, with percentages ranging from 2% to 4% in 0.5% increments. Additionally, pure water was incorporated in percentages ranging from 2% to 4% in 1% increments, and Portland cement was added at a constant content of 1%. The components were mixed at room temperature and subsequently compacted using a gyratory compactor with 150 gyrations. Prior to testing, the samples underwent a two-stage treatment process: initially, they were placed in an oven at 60°C for 48 hours, followed by a 24-hour period of air curing. The Hamburg wheel tracking test was performed to evaluate the samples’ resistance to rutting. Additionally, the Indirect Tensile Strength (ITS) test and the Semi-Circular Beam (SCB) test were conducted to assess their resistance to cracking. Upon analyzing the test results, it was observed that the samples’ resistance to rutting decreased with higher asphalt and moisture content. In contrast, ITS and SCB tests revealed that the samples’ resistance to cracking initially increased with higher asphalt and moisture content, peaking at a certain point, and then decreased, forming a bell-curve pattern.

Keywords: cold in-place, indirect tensile strength, recycling, emulsified asphalt, semi-circular beam

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Authors: Zhang Lei, Zhao Qingrong, Wang Chen, Zhang Sufang, Zhang Hanguo

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Larch is the main afforestation and timber tree species in Northeast China, and drought is one of the main factors limiting the growth of Larch and other organisms in Northeast China. In order to further explore the mechanism of Larch drought resistance, PEG was used to simulate drought stress. The full-length sequencing of Larch embryogenic callus under PEG simulated drought stress was carried out by combining Illumina-Hiseq and SMRT-seq. A total of 20.3Gb clean reads and 786492 CCS reads were obtained from the second and third generation sequencing. The de-redundant transcript sequences were predicted by lncRNA, 2083 lncRNAs were obtained, and the target genes were predicted, and a total of 2712 target genes were obtained. The de-redundant transcripts were further screened, and 1654 differentially expressed genes (DEGs )were obtained. Among them, different DEGs respond to drought stress in different ways, such as oxidation-reduction process, starch and sucrose metabolism, plant hormone pathway, carbon metabolism, lignin catabolic/biosynthetic process and so on. This study provides basic full-length sequencing data for the study of Larch drought resistance, and excavates a large number of DEGs in response to drought stress, which helps us to further understand the function of Larch drought resistance genes and provides a reference for in-depth analysis of the molecular mechanism of Larch drought resistance.

Keywords: larch, drought stress, full-length transcriptome sequencing, differentially expressed genes

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Authors: Novutry Siregar, Afdal, Emilzon Taslim

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Hyaline Membrane Disease (HMD) is the main cause of respiratory failure in preterm neonates caused by surfactant deficiency. Nasal Continuous Positive Airway Pressure (NCPAP) is the therapy for HMD. The success of therapy is determined by gestational age, birth weight, HMD grade, time of NCAP administration, and time of breathing frequency recovery. The aim of this research is to identify the predictive factor of NCPAP therapy success in preterm neonates with HMD. This study used a cross-sectional design by using medical records of patients who were treated in the Perinatology of the Pediatric Department of Dr. M. Djamil Padang Central Hospital from January 2015 to December 2017. The samples were eighty-two neonates that were selected by using the total sampling technique. Data analysis was done by using the Chi-Square Test and the Multiple Logistic Regression Prediction Model. The results showed the success rate of NCPAP therapy reached 53.7%. Birth weight (p = 0.048, OR = 3.34 95% CI 1.01-11.07), HMD grade I (p = 0.018, OR = 4.95 CI 95% 1.31-18.68), HMD grade II (p = 0.044, OR = 5.52 95% CI 1.04-29.15), and time of breathing frequency recovery (p = 0,000, OR = 13.50 95% CI 3.58-50, 83) are the predictive factors of NCPAP therapy success in preterm neonates with HMD. The most significant predictive factor is the time of breathing frequency recovery.

Keywords: predictive factors, the success of therapy, NCPAP, preterm neonates, HMD

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Authors: Prathibha Ganesan

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This paper discusses discontents of inhabitants in the landfills and its culmination into resistance against centralised waste disposal during the last three decades in Kerala. The study is based on a sample survey of 175 households located in the landfill sites and city limits of two Municipal Corporations viz. Thrissur and Cochin. The study found that waste is dumped in the periphery of the urban area where economically and socially vulnerable people are densely populated. Moreover, landfill sites are unscientifically managed to cause severe socio-economic and health issues to the local people, finally leading to their mobilisation and persistent struggle. The struggles often culminate in the closure of landfills or forced relocation or abandonment of the region by the community. The study concluded that persistent people’s struggles compel the local state to either find alternatives to centralised solid waste management system or use political power to subsume the local resistance. The persistence of the struggles determined the type waste governance adopted by the local governments.

Keywords: solid waste management, municipal corporation, resistance movements, urban, Kerala

Procedia PDF Downloads 267

Authors: Chung-Young Lee, Se-Hee Ahn, Jun-Gu Choi, Youn-Jeong Lee, Hyuk-Joon Kwon, Jae-Hong Kim

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A/chicken/Korea/01310/2001 (H9N2) (01310) was passaged through embryonated chicken eggs (ECEs) by 20 times (01310-E20), and it has been used for an inactivated oil emulsion vaccine in Korea. After sequential passages, 01310-E20 showed higher pathogenicity in ECEs and acquired multiple mutations including a potential N-glycosylation at position 133 (H3 numbering) in HA and 18aa-deletion in NA stalk. To evaluate the effect of these mutations on the mammalian pathogenicity and resistance to non-specific inhibitors, we generated four PR8-derived recombinant viruses with different combinations of HA and NA from 01310-E2 and 01310-E20 (rH2N2, rH2N20, rH20N2, and rH20N20). According to our results, recombinant viruses containing 01310 E20 HA showed higher growth property in MDCK cells and higher virulence on mice than those containing 01310 E2 HA regardless of NA. The hemagglutination activity of rH20N20 was less inhibited by egg white and mouse lung extract than that of other recombinant viruses. Thus, the increased pathogenicity of 01310-E20 may be related to both higher replication efficiency and resistance to non-specific inhibitors in mice.

Keywords: avian influenza virus, egg adaptation, H9N2, N-glycosylation, stalk deletion of neuraminidase

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Authors: Fouad Berrabeh, Sabir Messalti

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The performances of the photovoltaic systems are very dependent on different conditions, such as solar irradiation, temperature, etc. Therefore, it is very important to provide detailed studies for different cases in order to provide continuously power, so the photovoltaic system must be properly sized. This paper presents the modelling and simulation of the photovoltaic cell using single diode model. I-V characteristics and P-V characteristics are presented and it verified at different conditions (irradiance effect, temperature effect, series resistance effect).

Keywords: photovoltaic cell, BP SX 150 BP solar photovoltaic module, irradiance effect, temperature effect, series resistance effect, I–V characteristics, P–V characteristics

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Authors: Yu-Hsien Lin, Yu-Ru Lin, Yung-Chun Wu

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This work demonstrates the ultra-thin poly-Si (polycrystalline Silicon) nanowire junctionless thin film transistors (NWs JL-TFT) with nickel silicide contact. For nickel silicide film, this work designs to use two-step annealing to form ultra-thin, uniform and low sheet resistance (Rs) Ni silicide film. The NWs JL-TFT with nickel silicide contact exhibits the good electrical properties, including high driving current (>10⁷ Å), subthreshold slope (186 mV/dec.), and low parasitic resistance. In addition, this work also compares the electrical characteristics of NWs JL-TFT with nickel silicide and non-silicide contact. Nickel silicide techniques are widely used for high-performance devices as the device scaling due to the source/drain sheet resistance issue. Therefore, the self-aligned silicide (salicide) technique is presented to reduce the series resistance of the device. Nickel silicide has several advantages including low-temperature process, low silicon consumption, no bridging failure property, smaller mechanical stress, and smaller contact resistance. The junctionless thin-film transistor (JL-TFT) is fabricated simply by heavily doping the channel and source/drain (S/D) regions simultaneously. Owing to the special doping profile, JL-TFT has some advantages such as lower thermal the budget which can integrate with high-k/metal-gate easier than conventional MOSFETs (Metal Oxide Semiconductor Field-Effect Transistors), longer effective channel length than conventional MOSFETs, and avoidance of complicated source/drain engineering. To solve JL-TFT has turn-off problem, JL-TFT needs ultra-thin body (UTB) structure to reach fully depleted channel region in off-state. On the other hand, the drive current (Iᴅ) is declined as transistor features are scaled. Therefore, this work demonstrates ultra thin poly-Si nanowire junctionless thin film transistors with nickel silicide contact. This work investigates the low-temperature formation of nickel silicide layer by physical-chemical deposition (PVD) of a 15nm Ni layer on the poly-Si substrate. Notably, this work designs to use two-step annealing to form ultrathin, uniform and low sheet resistance (Rs) Ni silicide film. The first step was promoted Ni diffusion through a thin interfacial amorphous layer. Then, the unreacted metal was lifted off after the first step. The second step was annealing for lower sheet resistance and firmly merged the phase.The ultra-thin poly-Si nanowire junctionless thin film transistors NWs JL-TFT with nickel silicide contact is demonstrated, which reveals high driving current (>10⁷ Å), subthreshold slope (186 mV/dec.), and low parasitic resistance. In silicide film analysis, the second step of annealing was applied to form lower sheet resistance and firmly merge the phase silicide film. In short, the NWs JL-TFT with nickel silicide contact has exhibited a competitive short-channel behavior and improved drive current.

Keywords: poly-Si, nanowire, junctionless, thin-film transistors, nickel silicide

Procedia PDF Downloads 237

Authors: Beata Pospiech

Abstract:

Separation of metal ions from aqueous solutions is important as well as difficult process in hydrometallurgical technology. This process is necessary for obtaining of clean metals. Solvent extraction and membrane processes are well known as separation methods. Recently, ionic liquids (ILs) are very often applied and studied as extractants and carriers of metal ions from aqueous solutions due to their good extractability properties for various metals. This work discusses a method to separate copper(II) and iron(III) from hydrochloric acid solutions by solvent extraction and transport across polymer inclusion membranes (PIM) with the selected ionic liquids as extractants/ion carriers. Cyphos IL 101 (trihexyl(tetradecyl)phosphonium chloride), Cyphos IL 104 (trihexyl(tetradecyl)phosphonium bis(2,4,4 trimethylpentyl)phosphi-nate), trioctylmethylammonium thiosalicylate [A336][TS] and trihexyl(tetradecyl)phosphonium thiosalicylate [PR4][TS] were used for the investigations. Effect of different parameters such as hydrochloric acid concentration in aqueous phase on iron(III) and copper(II) extraction has been investigated. Cellulose triacetate membranes with the selected ionic liquids as carriers have been prepared and applied for transport of iron(IIII) and copper(II) from hydrochloric acid solutions.

Keywords: copper, iron, ionic liquids, solvent extraction

Procedia PDF Downloads 279

Authors: Gulnaz Khan, Meha F. Aftab, Munazza Murtaza, Rizwana S. Waraich

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Advanced glycation end products (AGEs) precursor and its abnormal accumulation cause damage to various tissues and organs. AGEs have pathogenic implication in several diseases including diabetes. Existing AGEs inhibitors are not in clinical use, and there is a need for development of novel inhibitors. The present investigation aimed at identifying the novel AGEs inhibitors and assessing their mechanism of action for treating insulin resistance in mice model of diabetes. Novel derivatives of benzylidene of indan-1,3-dione were synthesized. The compounds were selected to study their action mechanism in improving insulin resistance, in vitro, in human hepatocytes and murine adipocytes and then, in vivo, in mice genetic model of diabetes (db/db). Mice were treated with novel derivatives of benzylidene of indane 1,3-dione. AGEs mediated ROS production was measured by dihydroethidium fluorescence assay. AGEs level in the serum of treated mice was observed by ELISA. Gene expression of receptor for AGEs (RAGE), PPAR-gamma, TNF-alpha and GLUT-4 was evaluated by RT-PCR. Glucose uptake was measured by fluorescent method. Microscopy was used to analyze glycogen synthesis in muscle. Among several derivatives of benzylidene of indan-1,3-dione, IDD-24, demonstrated highest inhibition of AGESs. IDD-24 significantly reduced AGEs formation and expression of receptor for advanced glycation end products (RAGE) in fat, liver of db/db mice. Suppression of AGEs mediated ROS production was also observed in hepatocytes and fat cell, after treatment with IDD-24. Glycogen synthesis was increased in muscle tissue of mice treated with IDD-24. In adipocytes, IDD-24 prevented AGEs induced reduced glucose uptake. Mice treated with IDD-24 exhibited increased glucose tolerance, serum adiponectin levels and decreased insulin resistance. The result of present study suggested that IDD-24 can be a possible treatment target to address glycotoxins induced insulin resistance.

Keywords: advance glycation end product, hyperglycemia, indan-1, 3-dione, insulin resistance

Procedia PDF Downloads 158

Authors: B. S. So, Y. H. Yoon, J. O. Jung, K. S. Bae

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Metal Injection Molding (MIM) is a technology that combines powder metallurgy and injection molding. Particularly, it is widely applied to the manufacture of precision mobile parts and automobile turbocharger parts because compact precision parts with complicated three-dimensional shapes that are difficult to machining are formed into a large number of finished products. The swing valve is a valve that adjusts the boost pressure of the turbocharger. Since the head portion is exposed to the harsh temperature condition of about 900 degrees in the gasoline GDI engine, it is necessary to use Inconel material with excellent heat resistance and abrasion resistance, resulting in high manufacturing cost. In this study, we developed a swing valve using a metal powder injection molding based hybrid material (Inconel 713C material with heat resistance is applied to the head part, and HK30 material with low price is applied to the rest of the body part). For this purpose, the process conditions of the metal injection molding were optimized to minimize the internal defects, and the effectiveness was confirmed by the fracture strength and fatigue test.

Keywords: hybrid metal injection molding, swing valve, turbocharger, double injection

Procedia PDF Downloads 213