Search results for: receptor diffusion

Authors: Yan Yu, Wang Yu, Chen Xintong, Liu Yi, Zhang Yanzhong, Wang Yanji, Chen Xingyu, Zhang Miaocheng, Tong Yi

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Neuromorphic computing based on spiking neural networks (SNNs) has emerged as a promising avenue for building the next generation of intelligent computing systems. Owing to its high-density integration, low power, and outstanding nonlinearity, memristors have attracted emerging attention on achieving SNNs. However, fabricating a low-power and robust memristor-based spiking neuron without extra electrical components is still a challenge for brain-inspired systems. In this work, we demonstrate a TiO₂-based threshold switching (TS) memristor to emulate a leaky integrate-and-fire (LIF) neuron without auxiliary circuits, used to realize single layer fully connected (FC) SNNs. Moreover, our TiO₂-based resistive switching (RS) memristors realize spiking-time-dependent-plasticity (STDP), originating from the Ag diffusion-based filamentary mechanism. This work demonstrates that TiO2-based memristors may provide an efficient method to construct hardware neuromorphic computing systems.

Keywords: leaky integrate-and-fire, memristor, spiking neural networks, spiking-time-dependent-plasticity

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Authors: Abul B. M. M. K. Islam, Mandar Dave, Roderick V. Jensen, Ashok R. Amin

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A systems approach was applied to characterize differentially expressed transcripts, bioinformatics pathways, and proteins and prostaglandins (PGs) from lung fibroblasts procured from wild-type (WT), COX-1-/- and COX-2-/- mice to understand system level control mechanism. Bioinformatics analysis of COX-2 and COX-1 ablated cells induced COX-1 and COX-2 specific signature respectively, which significantly overlapped with an 'IL-1β induced inflammatory signature'. This defined novel cross-talk signals that orchestrated coordinated activation of pathways of sterile inflammation sensed by cellular stress. The overlapping signals showed significant over-representation of shared pathways for interferon y and immune responses, T cell functions, NOD, and toll-like receptor signaling. Gene Ontology Biological Process (GOBP) and pathway enrichment analysis specifically showed an increase in mRNA expression associated with: (a) organ development and homeostasis in COX-1-/- cells and (b) oxidative stress and response, spliceosomes and proteasomes activity, mTOR and p53 signaling in COX-2-/- cells. COX-1 and COX-2 showed signs of functional pathways committed to cell cycle and DNA replication at the genomics level. As compared to WT, metabolomics analysis revealed a significant increase in COX-1 mRNA and synthesis of basal levels of eicosanoids (PGE2, PGD2, TXB2, LTB4, PGF1α, and PGF2α) in COX-2 ablated cells and increase in synthesis of PGE2, and PGF1α in COX-1 null cells. There was a compensation of PGE2 and PGF1α in COX-1-/- and COX-2-/- cells. Collectively, these results support a broader, differential and collaborative regulation of both COX-1 and COX-2 pathways at the metabolic, signaling, and genomics levels in cellular homeostasis and sterile inflammation induced by cellular stress.

Keywords: cyclooxygenases, inflammation, lung fibroblasts, systemic

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Authors: Dalal N. Hammod, Ekhlas K. Gbashi

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Today, cryptography is used in many applications to achieve high security in data transmission and in real-time communications. AES has long gained global acceptance and is used for securing sensitive data in various industries but has suffered from slow processing and take a large time to transfer data. This paper suggests a method to enhance Advance Encryption Standard (AES) Algorithm based on time and permutation. The suggested method (MAES) is based on modifying the SubByte and ShiftRrows in the encryption part and modification the InvSubByte and InvShiftRows in the decryption part. After the implementation of the proposal and testing the results, the Modified AES achieved good results in accomplishing the communication with high performance criteria in terms of randomness, encryption time, storage space, and avalanche effects. The proposed method has good randomness to ciphertext because this method passed NIST statistical tests against attacks; also, (MAES) reduced the encryption time by (10 %) than the time of the original AES; therefore, the modified AES is faster than the original AES. Also, the proposed method showed good results in memory utilization where the value is (54.36) for the MAES, but the value for the original AES is (66.23). Also, the avalanche effects used for calculating diffusion property are (52.08%) for the modified AES and (51.82%) percentage for the original AES.

Keywords: modified AES, randomness test, encryption time, avalanche effects

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Authors: Mansur Abdulrasheed, Ibrahim I. Hussein, Ahmed M. Mubarak, Ahmed F. Umar

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This study was aimed at evaluating the phytochemical constituents and the antimicrobial activity of the seed oil of Moringa oleifera and garlic against some selected food-borne microorganisms (Staphylococcus aureus, Escherichia coli, Salmonella spp and Pseudomonas aeruginosa) using disc diffusion method. The results of the phytochemical screening revealed differences in the presence of the phytochemicals among the extracts. Saponins were detected in both Moringa oleifera and garlic seed oil, while alkaloid and tannins were observed in seed oil of garlic. Furthermore, the antibacterial assay results show that the seed oil of Moringa oleifera was inactive against all the tested organisms, even at 100 % concentration. In contrast, garlic oil was found to be active against all the tested organisms. The highest inhibition was observed in E. coli (12 mm)at 100 % concentration, while at 20 % concentration, Salmonella Sp and P. aeruginosa showed the least inhibit on (6 mm). The antimicrobial activity of the seed oil of garlic may be attributed to its phytochemicals components which were not detected in the seed oil of Moringa oleifera. The results of this study have shown the potentials of the seed oil of garlic as an antimicrobial agent more especially in foods, by inhibiting the growth of the test organisms, which range from food-borne pathogens to food spoilage organisms.

Keywords: antimicrobial, garlic, Moringa oleifera, food borne pathogens

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Authors: Xinyong Li

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A new coupling system was constructed by combining photo-electrochemical cell with eletro-fenton cell (PEC-EF). The electrode material in this system was derived from MnyFe₁₋yCo Prussian-Blue-Analog (PBA). Mn₀.₄Fe₀.₆Co₀.₆₇-N@C spin-coated on carbon paper behaved as the gas diffusion cathode and Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ spin-coated on fluorine-tin oxide glass (FTO) as anode. The two separated cells could degrade Sulfamethoxazole (SMX) simultaneously and some coupling mechanisms by PEC and EF enhancing the degradation efficiency were investigated. The continuous on-site generation of H₂O₂ at cathode through an oxygen reduction reaction (ORR) was realized over rotating ring-disk electrode (RRDE). The electron transfer number (n) of the ORR with Mn₀.₄Fe₀.₆Co₀.₆₇-N@C was 2.5 in the selected potential and pH range. The photo-electrochemical properties of Mn₀.₄Fe₀.₆Co₀.₆₇O₂.₂ were systematically studied, which displayed good response towards visible light. The photo-induced electrons at anode can transfer to cathode for further use. Efficient photo-electro-catalytic performance was observed in degrading SMX. Almost 100% SMX removal was achieved in 120 min. This work not only provided a highly effective technique for antibiotic treatment but also revealed the synergic effect between PEC and EF.

Keywords: Electro-Fenton, photo-electrochemical, synergic effect, sulfamethoxazole

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Authors: Dorsaf Ben Malek

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The function of culture in language teaching changed because of globalization and the latest technologies. English became a lingua franca which resulted in altering the teaching objectives. The re-evaluation of cultural awareness is one of them. Business English teaching has also been subject to all these changes. It is therefore a wrong idea if we try to consider it as a diffusion of unlimited listing of lexis, diagrams, charts, and statistics. In fact, business students’ future career will require business terminology together with intercultural communicative competence (ICC) to handle different multicultural encounters and contribute to the international community. The first part of this paper is dedicated to the necessity of empowering business students with intercultural communicative competence and the second turns around the potential of multicultural literature in implementing ICC in business English teaching. This was proved through a qualitative action research done on a group of Tunisian MA business students. It was an opportunity to discover the potential of multicultural literature together with inquiry-based learning in enhancing business students’ intercultural communicative competence. Data were collected through classroom observations, journals and semi-structured interviews. Results were in favour of using multicultural literature to enhance business students’ ICC. In addition, the short story may be a motivating tool to read literature, and inquiry-based learning can be an effective approach to teaching literature.

Keywords: intercultural communicative competence, multicultural literature, short stories, inquiry-based learning

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Authors: Mouustafa A. Fadel, Ahmed Bani Hammad, Faisal Al Hosany, Osama Iwaimer

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Covering materials of greenhouses is the most governing component of the construction which controls two major parameters the amount of light and heat diffused from the surrounding environment into the internal space. In hot areas, balancing between inside and outside the greenhouse consumes most of the energy spent in production systems. In this research, a special testing apparatus was fabricated to simulate the structure of the greenhouse provided with a 400W full spectrum light. Tests were carried out to investigate the effectiveness of different commercial covering material in light and heat diffusion. Twenty one combinations of Fiberglass, Polyethylene, Polycarbonate, Plexiglass and Agril (PP nonwoven fabric) were tested. It was concluded that Plexiglass was the highest in light transparency of 87.4% where the lowest was 33% and 86.8% for Polycarbonate sheets. The enthalpy of the air moving through the testing rig was calculated according to air temperature differences between inlet and outlet openings. The highest enthalpy value was for one layer of Fiberglass and it was 0.81 kj/kg air while it was for both Plexiglass and blocked Fiberglass with a value of 0.5 kj/kg air. It is concluded that, although Plexiglass has high level of transparency which is indeed very helpful under low levels of solar flux, it is not recommended under hot arid conditions where solar flux is available most of the year. On the other hand, it might be a disadvantage to use Plixeglass specially in summer where it helps to accumulate more heat inside the greenhouse.

Keywords: greenhouse, covering materials, aridlands, environmental control

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Authors: Imene Medfouni

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In the context of postcolonial Algeria, language policy, language planning as well as language attitudes have recently stirred up contested debates in higher education system. This linguistic and politically-oriented conflict have constantly created a complex environment for learning. In the light of this observation, English language situates itself at the core of this debate with respects to its international status and potential influences. This presentation is based on ongoing research that aims to gain a better understanding of the introduction of English as a medium of instruction (EMI) in a postcolonial context, marked by multilingualism and language conflict. This research offers interesting insights to critically explore EMI from different perspectives: policy, practices, and attitudes. By means of methodological triangulation, this research integrates a mixed approach, whereby the sources of data triangulation will be elicited from the following methods: classroom observations, document analysis, focus groups, questionnaires and interviews. Preliminary findings suggest that English language might not replace French status in Algerian universities because of the latter strong presence and diffusion within Algerian linguistic landscape.

Keywords: English as a lingua franca, English as a medium of instruction, language policy and planning, multilingualism, postcolonial contexts, World Englishes

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Authors: Lin Dong-Yih, Yang S. M., Huang B. W., Lian J. A.

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Super duplex stainless steel has excellent mechanical properties and corrosion resistance. It becomes important structural material as its application has been extended to the fields such as renewable energy and the chemical industry because of its excellent properties. As examples are offshore wind power, solar cell machinery, and pipes in the chemical industry. The mechanical properties and corrosion resistance of super duplex stainless steel can be eliminated by welding due to the precipitation of the hard and brittle σ phase, which is rich of chromium, and molybdenum elements. This paper studies the influence of carbon element on the phase transformation of -ferrite and σ phase in 2507 super duplex stainless steel. The 2507 will be under argon gas protection welded with 316 and 316L extra low carbon stainless steel separately. The microstructural phases of stainless steels before and after welding, in fusion, heat affected zones, and base material will be studied via X-ray, OM, SEM, EPMA i.e. their quantity, size, distribution, and morphology. The influences of diffusion by carbon element will be compared according to the microstructures, hardness, and corrosion tests.

Keywords: complex stainless steel, welding, phase formation, carbon element, sigma phase, delta ferrite

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Authors: Jinliang Yuan, Jong-Sung Yu, Bengt Sundén

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A computational fluid dynamics (CFD) model is developed for rechargeable non-aqueous electrolyte lithium-air batteries with a partial opening for oxygen supply to the cathode. Multi-phase transport phenomena occurred in the battery are considered, including dissolved lithium ions and oxygen gas in the liquid electrolyte, solid-phase electron transfer in the porous functional materials and liquid-phase charge transport in the electrolyte. These transport processes are coupled with the electrochemical reactions at the active surfaces, and effects of discharge reaction-generated solid Li2O2 on the transport properties and the electrochemical reaction rate are evaluated and implemented in the model. The predicted results are discussed and analyzed in terms of the spatial and transient distribution of various parameters, such as local oxygen concentration, reaction rate, variable solid Li2O2 volume fraction and porosity, as well as the effective diffusion coefficients. It is found that the effect of the solid Li2O2 product deposited at the solid active surfaces is significant on the transport phenomena and the overall battery performance.

Keywords: Computational Fluid Dynamics (CFD), modeling, multi-phase, transport phenomena, lithium-air battery

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Authors: Eugene Ivanov, Eduardo del-Rio, Igor Kapchenko, Maija Nystrӧm, Juha Kotila

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Series of low modulus beta Ti alloy billets and powders can be produced in commercial quantities using a combination of electron beam melting (EBM) and EIGA atomization processes. In the present study, TNZT alloy powder was produced and processed in the EOSINT M290 laser sintering system to produce parts for mechanical testing. Post heat treatments such as diffusion annealing to reduce internal stresses or hot isostatic pressing to remove closed pores were not applied. The density can visually be estimated to be > 99,9 %. According to EDS study Nb, Zr, and Ta are distributed homogeneously throughout the printed sample. There are no indications for any segregation or chemical inhomogeneity, i.e. variation of the element distribution. These points to the fact that under the applied experimental conditions the melt generated by the laser rapidly cools down in the SLM (Selective Laser Melting) process. The selective laser sintering yielded dense structures with relatively good surface quality. The mechanical properties, especially the elongation (24%) along with tensile strength ( > 500MPa) and modulus of elasticity (~60GPa), were found to be promising compared to titanium alloys in general.

Keywords: beta titanium alloys, additive manufacturing, powder, implants

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Authors: Salahaedin Waiezi, Nik Ahmad Nizam Nik Malek, Hassan Abdelmagid Elzamzami, Shahrulnizahana Mohammad Din

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A green and safe approach to the synthesis of silver nanoparticles (AgNP) can be performed using plant leaf extract as the reducing agent. Hence, this paper reports the biosynthesis of AgNP using Clinacanthus nutans plant extract. C. nutans is known as belalai gajah in Malaysia and is widely used as a medicinal herb locally. The biosynthesized AgNP, using C. nutans aqueous extract at pH 10, with the reaction temperature of 70°C and 48 h reaction time, was characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and transmission electron microscope (TEM). A peak appeared in the UV-Vis spectra at around 400 nm, while XRD confirmed the crystal structure of AgNP, with the average size between 20 to 30 nm, as shown in FESEM and TEM. The antibacterial activity of the biosynthesized AgNP, which was performed using the disc diffusion technique (DDT) indicated effective inhibition against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. In contrast, minimal antibacterial activity was detected against Enterococcus faecalis and methicillin-resistant Staphylococcus aureus (MRSA). In general, AgNP produced using C. nutans leaf extract possesses potential antibacterial activity.

Keywords: silver nanoparticles, Clinacanthus nutans, antibacterial agent, biosynthesis

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Authors: Ritu Karwasra, Surender Singh

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Inflammation is an important physiological response of the body’s self-defense system that helps in eliminating and protecting organism from harmful stimuli and in tissue repair. It is a highly regulated protective response which helps in eliminating the initial cause of cell injury, and initiates the process of repair. The present study was designed to evaluate the ameliorative effect of pomegranate rind extract on pain and inflammation. Hydroalcoholic standardized rind extract of pomegranate at doses 50, 100 and 200 mg/kg and indomethacin (3 mg/kg) was tested against eddy’s hot plate induced thermal algesia, carrageenan (acute inflammation) and Complete Freund’s Adjuvant (chronic inflammation) induced models in Wistar rats. Parameters analyzed were inhibition of paw edema, measurement of joint diameter, levels of GSH, TBARS, SOD, TNF-α, radiographic imaging, tissue histology and synovial expression of pro-inflammatory cytokine receptor (TNF-R1). Radiological and light microscopical analysis were carried out to find out the bone damage in CFA-induced chronic inflammatory model. Findings of the present study revealed that pomegranate rind extract at a dose of 200 mg/kg caused a significant (p<0.05) reduction in paw swelling in both the inflammatory models. Nociceptive threshold was also significantly (p<0.05) improved. Immunohistochemical analysis of TNF-R1 in CFA-induced group showed elevated level, whereas reduction in level of TNF-R1 was observed in pomegranate (200 mg/kg). Henceforth, we might say that pomegranate produced a dose-dependent reduction in inflammation and pain along with the reduction in levels of oxidative stress markers and tissue histology, and the effect was found to be comparable to that of indomethacin. Thus, it can be concluded that pomegranate is a potential therapeutic target in the pathogenesis of inflammation and pain, and punicalagin is the major constituents found in rind extract might be responsible for the activity.

Keywords: carrageenan, inflammation, nociceptive-threshold, pomegranate, histopathology

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Authors: Ajay Gogia, Svs Deo, Dn Sharma, Atul Batra, Ashutash Mishra

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Background and Aims: Breast cancer in women aged less than 25 years (defined as very young breast cancer, VYBC) is rare and accounts for 0.25% of all breast cancer in the West. There is no data available on VYBC from developing countries. The aim of this study was to analyze the clinical, pathological, and prognostic factors and outcomes in VYBC. Methods: This retrospective analysis was performed on 80 patients aged 25 years or less (screened 8000 files of female BC) who were registered at All India Institute of Medical Sciences (AIIMS), New Delhi, India, over a 15-year period between 2011 and 2023. Results: The median age was 21.5 years (range 16-25). A positive family history (siblings and parents) was elicited in 30% of cases, and breast cancer gene (BRCA1/2) mutation was found in 33% of cases patients. Ten patients (12.5%) patients have pregnancy-associated breast cancer (BC detected during pregnancy or 1 year after postpartum period). The TNM stage distribution was Stage I was 0, stage II -30%, stage III –60% and Stage IV -10 %patients. Seventy percent of tumors were high grade, and 90% had pathological node-positive disease. Estrogen, Progesterone, and human epidermal growth factor receptor 2 (HER2)/neu positivity were 25%,25% and 35%, respectively. Triple-negative breast cancer constituted 40% of patients. With a median follow-up of 42 months, 3 years, relapse-free survival (nonmetastatic disease), progression-free survival (metastatic disease) and overall survival were 30%, 15% and 50%, respectively. Conclusions: Very young women constituted 1% of all breast cancer cases. Advanced disease at presentation and high-risk pathological features result in poor outcomes. One-third of VYBCs are associated with BRCA mutation, which requires genetic counseling and risk reduction surgery if required. Due to the aggressive behavior of BC in this age group, need early diagnosis and prompt treatment

Keywords: very young, breast cancer, outcome, developing country, India

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Authors: M. Lizzy Madiwani, Ignatious Ncube, Evelyn Madoroba

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This study was designed to determine the distribution of pathogenic bacteria in household raised chickens and study their virulence and antibiotic profiles. For this purpose, 40 chickens were purchased from families in the Capricorn district and sacrificed for sampling. Tissues were cultured on different bacteriological media followed by biotyping using Matrix-assisted Laser Desorption Ionization-time of Flight (MALDI-TOF). Disk diffusion test was performed to determine the antibiotic susceptibility profiles of these bacteria. Out of a total of 160 tissue samples evaluated, E. coli and Salmonella were detected in these tissues. Furthermore, determination of the pathogenic E. coli and Salmonella strains at species level using primer sets that target selected genes of interest in the polymerase chain reaction (PCR) assay was employed. The invA gene, a confirmatory gene of Salmonella was detected in all the Salmonella isolates. The study revealed that there is a high distribution of Salmonella and pathogenic E. coli in these chickens. Therefore, further studies on identification at the species level are highly recommended to provide management and sanitation practices to lower this prevalence. The antimicrobial susceptibly data generated from this study can be a valuable reference to veterinarians for treating bacterial diseases in poultry.

Keywords: antimicrobial, Escherichia coli, pathogens, Salmonella

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Authors: Mandeep Kataria, Ankita Thakur

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Glycyrrhiza glabra grows in the sub- tropical and warm temperate regions of the world, in Mediterranean countries and China, America, Europe, Asia and Australia. It grows in areas with sunny, dry and hot climates. It has numerous medicinal properties like it is used to cure Peptic Ulcers, Canker sores, Eczema, Indigestion and Upper Respiratory Infections. Biosynthetic methods such as plant extract have emerged as a simple and viable alternative to more complex chemical synthetic procedures to obtain nanomaterials. Extract from plant may act both as reducing and capping agents in silver nanoparticles synthesis. In the present work, Green Silver nanoparticles were successfully formulated from bioreduction of silver nitrate solutions using Glycyrrhiza glabra root extract. These Green Silver nanoparticles have been appropriately characterized using Visible spectroscopy, colour change. The Antimicrobial activity was done by Agar disc diffusion assay. AgNPs were developed by using aqueous root extract of Glycyrrhiza glabra, which acts as a reducing as well as stabilizing agent. The green synthetic method is a fast, low cost and eco-friendly process in the field of nanotechnology. The study revealed that the green-synthesized silver nanoparticle provides a promising approach for antimicrobial activity.

Keywords: Glycyrrhiza glabra, nanoparticles, antimicrobial activity, aqueous extract

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Authors: Sahar M. El-Gowilly, Mai M. Helmy, Hanan M. El-Gowelli

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Methotrexate (MTX) is widely used in treatment of cancers and autoimmune diseases. However, nephrotoxicity is one of the most important side effects of MTX. The peroxisome proliferator-activated receptor gamma agonist, pioglitazone (PIO), is known to exert anti-inflammatory and reno-protective effects in various kidney injuries. The purpose of this study was to investigate the potential involvement of endothelial damage in MTX-induced renal injury and to elaborate the possible protective effect of PIO against MTX-induced nephropathy. Compared with saline-treated rats, treatment with MTX (7 mg/kg for 3 day) caused significant elevations in serum levels of urea and creatinine, increased renal nitrate/nitrite level and impaired renovascular responsiveness of isolated perfused kidney to endothelium-dependent vasodilations induced by acetylcholine (0.01-2.43 nmol) and isoprenaline (1µmol). These effects were abolished by concurrent treatment with PIO (2.5 mg/kg, for 5 days starting two days before MTX). Alternatively, MTX treatment did not affect endothelium-independent renovascular relaxation induced by sodium nitroprusside (1-30 μmole). The possibility that alterations in renal antioxidants, circulating cytokine and apoptotic factor (Fas) levels contributed to MTX-PIO interaction was assessed. PIO treatment abrogated renal oxidative stress (decreased reduced glutathione and catalase activity and increased malondialdehyde), elevated serum cytokine (interleukin-6, interleukin-10, tumor necrosis factor-alpha and transforming growth factor-beta1) and Fas induced by MTX. Histologically, MTX caused defused tubular cells swelling and vacuolization associated with endothelial damage in renal arterioles. These effects disappeared upon co-treated with PIO. Collectively, PIO abolished MTX-induced endothelium dysfunction and nephrotoxicity via ameliorating oxidative stress and rectifying cytokines and Fas abnormalities caused by MTX.

Keywords: methotrexate, pioglitazone, endothelium, kidney

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Authors: Sahar M. El-Gowilly, Mai M. Helmy, Hanan M. El-Gowelli

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Methotrexate (MTX) is widely used in treatment of cancers and autoimmune diseases. However, nephrotoxicity is one of its most important side effects. The peroxisome proliferator-activated receptor gamma agonist, pioglitazone, is known to exert antiinflammatory and reno-protective effects in various kidney injuries. The purpose of this study was to investigate the potential involvement of endothelial damage in MTX-induced renal injury and to elaborate the possible protective effect of pioglitazone against MTX-induced endothelial impairment. Compared with saline-treated rats, treatment with MTX (7 mg/kg for 3 day) caused significant elevations in serum levels of urea and creatinine, increased renal nitrate/nitrite level and impaired renovascular responsiveness of isolated perfused kidney to endothelium-dependent vasodilations induced by acetylcholine (0.01-2.43 nmol) and isoprenaline (1µmol). These effects were abolished by concurrent treatment with pioglitazone (2.5 mg/kg, for 5 days starting two days before MTX). Alternatively, MTX treatment did not affect endothelium-independent renovascular relaxation induced by sodium nitroprusside (0.001-10 μmole). The possibility that alterations in renal antioxidants, circulating cytokine and apoptotic factor (Fas) levels contributed to MTX-pioglitazone interaction was assessed. Pioglitazone treatment abrogated renal oxidative stress (decreased reduced glutathione and catalase activity and increased malondialdehyde), elevated serum cytokine (interleukin-6, interleukin-10, tumor necrosis factor-alpha and transforming growth factor-beta1) and Fas induced by MTX. Histologically, MTX caused defused tubular cells swelling and vacuolization associated with endothelial damage in renal arterioles. These effects disappeared upon co-treated with pioglitazone. Collectively, pioglitazone abolished MTX-induced endothelium dysfunction and nephrotoxicity via ameliorating oxidative stress and rectifying cytokines and Fas abnormalities caused by MTX.

Keywords: methotrexate, pioglitazone, endothelium, kidney

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Authors: I. L. Ibrahim, A. Mann, A. Ndanaimi

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The research involved phytochemical screening, antibacterial activities and mineral determination by flame photometry of the crude extract of Brysocarpus coccineus schum indeed were carried out. The result of Phytochemical screening reveal tha saponins, alkaloids, cardiac glycosides, and anthraquinones were present. This suggests that the plant extract could be used as anti-inflammatory and anti-bleeding agents. Estimation of mineral content shows that the crude extract of B. coccineus contains 0.73 (Na+), 1.06 (K+) and 1.98 (Ca+) which justifies its use to be safe for hypertensive patients and could be used to lower blood pressure. The antibacterial properties of aqueous and ethanol extract were studied against some bacteria; pseudomonas aeruginosa, Escherichia coli, Bacilus subtilis, Klebsilla penmuoniae by disc diffusion method. The aqueous extract showed significant activity against the organisms while the ethanol at concentrations 5-10mg/ml ethanol extract showed significant zone of inhibition against the organisms, E. coli, (19 mm), B. cereus (12 mm), P. aeruginosa (11 mm), K. pnemuoniae (11 mm). Minimum inhibitory concentration (MIC) was carried with considerable effect of inhibition on the organisms. The MIC values observed were 1, 24, 16 and 19 mm against E. coli, B. cereus, P. aeruginosa and K. pnemuoniae respectively. Therefore, the plant could be a potential source of antibacterial agent although more pharmacological and clinical study may be recommended.

Keywords: phytochemicals, microorganisms, screenings, mineral ions

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Authors: Mehani Mouna, Ladjel segni

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Humans use plants for thousands of years to treat various ailments, In many developing countries, Much of the population relies on traditional doctors and their collections of medicinal plants to cure them. Essential oils have many therapeutic properties. In herbal medicine, They are used for their antiseptic properties against infectious diseases of fungal origin, Against dermatophytes, Those of bacterial origin. The aim of our study is to determine the antimicrobial effect of essential oils of the plant Schinus molle on some pathogenic bacteria. It is a medicinal plant used in traditional therapy. Essential oils have many therapeutic properties. In herbal medicine, They are used for their antiseptic properties against infectious diseases of fungal origin, Against dermatophytes, Those of bacterial origin. The test adopted is based on the diffusion method on solid medium (Antibiogram), This method allows to determine the susceptibility or resistance of an organism according to the sample studied. Our study reveals that the essential oil of the plant Schinus molle has a different effect on the resistance of germs: For Pseudomonas aeruginosa strain is a moderately sensitive with an inhibition zone of 10 mm, Further Antirobactere, Escherichia coli and Proteus are strains that represent a high sensitivity, A zone of inhibition equal to 14.66 mm.

Keywords: Essential oil, microorganism, antibiogram, shinus molle

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Authors: Jaehyug Lee, Tae-Ho Song

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Vacuum insulation panel (VIP) can achieve very low thermal conductivity by evacuating its inner space. Heat transfer in the core materials of highly-evacuated VIP occurs by conduction through the solid structure and radiation through the pore. The effect of various scattering modes in combined conduction-radiation in VIP is investigated through numerical analysis. The discrete ordinates interpolation method (DOIM) incorporated with the commercial code FLUENT® is employed. It is found that backward scattering is more effective in reducing the total heat transfer while isotropic scattering is almost identical with pure absorbing/emitting case of the same optical thickness. For a purely scattering medium, the results agree well with additive solution with diffusion approximation, while a modified term is added in the effect of optical thickness to backward scattering is employed. For other scattering phase functions, it is also confirmed that backwardly scattering phase function gives a lower effective thermal conductivity. Thus, the materials with backward scattering properties, with radiation shields are desirable to lower the thermal conductivity of VIPs.

Keywords: combined conduction and radiation, discrete ordinates interpolation method, scattering phase function, vacuum insulation panel

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Authors: Sihem Benmimoune, Abdelbaki Lemgharbi, Ahmed Ait Yahia, Abdelkrim Kameli

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Our study is based on chemical and phytochemical characterization of Artemisia absinthium L and in vitro tests to demonstrate the biological activities of essential oil and natural extract. A qualitative and quantitative comparison of the essential oil extracted by two extraction procedures was performed by analysis of CG/SM and the yield calculation. The method of hydrodistillation has a chemical composition and provides oil content than the best training water vapor. These oils are composed mainly of thujone followed chamazulene and ρ-cymene. The antimicrobial activity of wormwood oil was tested in vitro by two methods (agar diffusion and microdilution) on four plant pathogenic fungi (Aspergillus sp, Botrytis cinerea, Fusarium culmorum and Helminthosporium sp). The study of the antifungal effect showed that this oil has an inhibitory effect counterpart the microorganisms tested in particular the strain Botrytis cinerea. Otherwise, this activity depends on the nature of the oil and the germ itself. The antioxidant activity in vitro was studied with the DPPH method. The activity test shows that the oil and extract of Artemisia absinthium have a very low antioxidant capacity compared to the antioxidants used as a reference. The extract has a potentially high antiradical power not from its oil. The quantitative determinations of phenolic compounds by the Folin-Ciocalteu revealed that absinthe is low in total polyphenols and tannins.

Keywords: artemisia absinthium, biological activities, essential oil, extraction processes

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Authors: Virendra J. Majarikar, Harikrishnan N. Unni

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This paper sets to demonstrate a modeling of electrokinetic mixing employing electroosmotic stationary and time-dependent microchannel using alternate zeta patches on the lower surface of the micromixer in a lab on chip microfluidic device. Electroosmotic flow is amplified using different 2D and 3D model designs with alternate and geometric zeta potential values such as 25, 50, and 100 mV, respectively, to achieve high concentration mixing in the electrokinetically-driven microfluidic system. The enhancement of electrokinetic mixing is studied using Finite Element Modeling, and simulation workflow is accomplished with defined integral steps. It can be observed that the presence of alternate zeta patches can help inducing microvortex flows inside the channel, which in turn can improve mixing efficiency. Fluid flow and concentration fields are simulated by solving Navier-Stokes equation (implying Helmholtz-Smoluchowski slip velocity boundary condition) and Convection-Diffusion equation. The effect of the magnitude of zeta potential, the number of alternate zeta patches, etc. are analysed thoroughly. 2D simulation reveals that there is a cumulative increase in concentration mixing, whereas 3D simulation differs slightly with low zeta potential as that of the 2D model within the T-shaped micromixer for concentration 1 mol/m³ and 0 mol/m³, respectively. Moreover, 2D model results were compared with those of 3D to indicate the importance of the 3D model in a microfluidic design process.

Keywords: COMSOL Multiphysics®, electrokinetic, electroosmotic, microfluidics, zeta potential

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Authors: Meryem Imane Babaghayou, Asma Abdelhafidi, Salem Fouad Chabira, Mohammed Sebaa

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A challenge of plastics industries is the realization of materials that resist the degradation in its application environment, and that to guarantee a longer life time therefore an optimal time of use. Blown extruded films of low-density polyethylene (LDPE) supplied by SABIC SAUDI ARABIA blown and extruded in SOFIPLAST company in Setif ALGERIA , have been subjected to climatic ageing in a sub-Saharan facility at Laghouat (Algeria) with direct exposure to sun. Samples were characterized by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques after prescribed amounts of time up to 8 months. It has been shown via these two techniques the impact of UV irradiation on the morphological development of a plastic material, especially the crystallinity degree which increases with exposure time. The reason of these morphological changes is related to photooxidative reactions leading to cross linking in the beginning and to chain scissions for an advanced stage of ageing this last ones are the first responsible. The crystallinity degree change is essentially controlled by the secondary crystallization of the amorphous chains whose mobility is enhanced by the chain scission processes. The diffusion of these short segments integrates the surface of the lamellae increasing in this way their thicknesses. The results presented highlight the complexity of the involved phenomena.

Keywords: Low Density poly (Ethylene), crystallinity, ageing, XRD, DSC

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Authors: Jyoti Manandhar Shrestha, Saurab Raj Joshi, Maya Shrestha, Prashanna Shrestha, Kshitij Chaulagain

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Background: The widespread use of non-steroidal anti-inflammatory drugs has increased the incidence of ulcer and serious complications, such as perforation and bleeding. Although, the H2 receptor blockers and proton pump inhibitors decrease the acid secretion and promote healing of ulcer, their value in preventing relapse, recurrence, “acid rebound” after cessation of therapy and associated long term adverse effects limit their utility. So to minimize this, the herbal plant Aloe vera having anti-oxidant, anti-inflammatory, mucus secreting, cyto-protective and healing property is believed to cure the peptic ulcer. Objectives: To observe whether oral treatment with Aloe vera gel can prevent peptic ulcer. Indomethacin and ethanol were used to induce gastric ulcers. Thirty six albino rats of either sex were randomly allotted to six groups of six animals each. The negative control was pretreated with normal saline, the positive controls received ranitidine (20 mg/kg) and the test group received Aloe vera gel (300 mg/kg) orally for eight days. Then, after a 24 hour fast Indomethacin (20 mg/kg) or 80% ethanol (2ml) was administered orally to induce ulceration. At the end of the study, the rats were sacrificed, their stomachs opened, the ulcer index studied and tissues sent for histopathological examination. Results: It was observed that, in indomethacin treated group, the ulcer index in control group was 8.167 ± 1.72.In the Aloe vera pretreated animals, the ulcer index was 2.83 ± 1.72 and the standard ranitidine pretreated group ulcer index was 1.67 ± 1.36. In ethanol treated group, the ulcer index in control group was 7.5 ± 2.73. In the Aloe vera pretreated animals, the ulcer index was 2.67 ± 1.75 and the standard ranitidine pretreated group ulcer index was 1.33±1.21. Both ranitidine and Aloe vera gel significantly prevented stomach from gastric ulceration induced by indomethacin and ethanol. Conclusion: The results indicated that Aloe vera gel is effective against indomethacin and ethanol mediated gastric ulcer.

Keywords: Aloe vera gel, ethanol, indomethacin, peptic ulcer, ranitidine

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Authors: Yi Sun, George Ed Rainger, Steve P. Watson

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Background: Beyond the classical roles in haemostasis and thrombosis, platelets are important in the initiation and development of various thrombo-inflammatory diseases. In atherosclerosis and deep vein thrombosis, for example, platelets bridge monocytes with endothelium and form heterotypic aggregates with monocytes in the circulation. This can alter monocyte phenotype by inducing their activation, stimulating adhesion and migration. These interactions involve cell surface receptor-ligand pairs on both cells. This list is likely incomplete as new interactions of importance to platelet biology are continuing to be discovered as illustrated by our discovery of PEAR-1 binding to FcεR1α. Results: We have developed a highly sensitive avidity-based assay to identify novel extracellular interactions among 126 recombinantly-expressed platelet cell surface and secreted proteins involved in platelet aggregation. In this study, we will use this method to identify novel platelet-monocyte interactions. We aim to identify ligands for orphan receptors and novel partners of well-known proteins. Identified interactions will be studied in preliminary functional assays to demonstrate relevance to the inflammatory processes supporting atherogenesis. Conclusions: Platelet-monocyte interactions are essential for the development of thromboinflammatory disease. Up until relatively recently, technologies only allow us to limit our studies on each individual protein interaction at a single time. These studies propose for the first time to study the cell surface platelet-monocyte interactions in a systematic large-scale approach using a reliable screening method we have developed. If successful, this will likely to identify previously unknown ligands for important receptors that will be investigated in details and also provide a list of novel interactions for the field. This should stimulate studies on developing alternative therapeutic strategies to treat vascular inflammatory disorders such as atherosclerosis, DVT and sepsis and other clinically important inflammatory conditions.

Keywords: membrane proteins, large-scale screening, platelets, recombinant expression

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Authors: Partha Sarathi Majee, S. Bhattacharyya

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Migration of a core-shell soft particle under the influence of an external electric field in an electrolyte solution is studied numerically. The soft particle is coated with a positively charged polyelectrolyte layer (PEL) and the rigid core is having a uniform surface charge density. The Darcy-Brinkman extended Navier-Stokes equations are solved for the motion of the ionized fluid, the non-linear Nernst-Planck equations for the ion transport and the Poisson equation for the electric potential. A pressure correction based iterative algorithm is adopted for numerical computations. The effects of convection on double layer polarization (DLP) and diffusion dominated counter ions penetration are investigated for a wide range of Debye layer thickness, PEL fixed surface charge density, and permeability of the PEL. Our results show that when the Debye layer is in order of the particle size, the DLP effect is significant and produces a reduction in electrophoretic mobility. However, the double layer polarization effect is negligible for a thin Debye layer or low permeable cases. The point of zero mobility and the existence of mobility reversal depending on the electrolyte concentration are also presented.

Keywords: debye length, double layer polarization, electrophoresis, mobility reversal, soft particle

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Authors: Christian C. Vaso, Rinlee Butch M. Cervera

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One of the most promising anode materials for solid oxide electrolysis cell (SOEC) application is the Sr-doped LaMnO₃ (LSM) which is known to have a high electronic conductivity but low ionic conductivity. To increase the ionic conductivity or diffusion of ions through the anode, Yttria-stabilized Zirconia (YSZ), which has good ionic conductivity, is proposed to be combined with LSM to create a composite electrode and to obtain a high mixed ionic and electronic conducting anode. In this study, composite of lanthanum strontium manganite and YSZ oxide, La_0.8Sr_0.2MnO₃/Zr_0.92Y_0.08O₂ (LSM/YSZ), with different wt.% compositions of LSM and YSZ were synthesized using solid-state reaction. The obtained prepared composite samples of 60, 50, and 40 wt.% LSM with remaining wt.% of 40, 50, and 60, respectively for YSZ were fully characterized for its microstructure by using powder X-ray diffraction (XRD), Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), and Scanning electron microscope/Energy dispersive spectroscopy (SEM/EDS) analyses. Surface morphology of the samples via SEM analysis revealed a well-sintered and densified pure LSM, while a more porous composite sample of LSM/YSZ was obtained. Electrochemical impedance measurements at intermediate temperature range (500-700 °C) of the synthesized samples were also performed which revealed that the 50 wt.% LSM with 50 wt.% YSZ (L50Y50) sample showed the highest total conductivity of 8.27x10^-1 S/cm at 600 ^oC with 0.22 eV activation energy.

Keywords: ceramics, microstructure, fuel cells, electrochemical impedance spectroscopy

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Authors: Sarita Kumari, Ranjit Kumar Upadhyay

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This paper deals with plankton-fish dynamics where the fish population is growing logistically and nonlinearly harvested. The interaction between phytoplankton and zooplankton population is considered to be Crowley-Martin type functional response. It has been assumed that phytoplankton grows logistically and is affected by a space-dependent growth rate. Conditions for the existence of a positive equilibrium point and their stability analysis (both local and global) have been discussed for the non-spatial system. We have discussed maximum sustainable yields as well as optimal harvesting policy for maximizing the economic gain. The stability and existence of Hopf –bifurcation analysis have been discussed for the spatial system. Different conditions for turning pattern formation have been established through diffusion-driven instability analysis. Numerical simulations have been carried out for both non-spatial and spatial models. Phase plane analysis, the largest Lyapunov exponent, and bifurcation theory are used to numerically analyzed the non-spatial system. Our study shows that spatial heterogeneity, the mortality rate of phytoplankton, and constant harvesting of the fish population each play an important role in the dynamical behavior of the marine system.

Keywords: optimal harvesting, pattern formation, spatial heterogeneity, Crowley-Martin functional response

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Authors: I. L. Ibrahim, A. Mann, B. A. Adam

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This project involved screening for antibacterial activity, phytochemical and mineral properties of Leptadenia hastata by flame photometry. The result of phytochemical screening reveals that the presence of flavonoids, tannins, saponins, alkaloids, steroidal, and anthraquinones while the cardiac glycoside was absent. This justifies the plant been used as anti-bleeding and anti-inflammatory agents. The result of flame photometry revealed that 1.85 % (Na), 0.65% (K) and 1.85 % (Ca) which indicates the safe nature of the plant extract as such could be used to lower high blood pressure. The antibacterial properties of both the aqueous and ethanolic extract were studied against some bacteria, Escherichia coli, Bacillus Cercus, Pseudomonas aeruginas, and Enterobacter aerogegens, by disc diffusion method and the result reveals that there are very good activities against the organism while the ethanolic extract at concentration 1.0 – 1.2 mg/ml. the ethanolic extract showed in considerable zone inhibition against bacteria’s; Escherichia coli, Bacillus Cercus, pseudomonas aeruginosa andklebsellapnemuoniae. Minimum inhibitory concentration (MIC) and minimum Bacterial concentration (MBC) were conducted with fairly good significant effect of inhibition on the organism, therefore, plant extract could be a potential source of antibacterial agent.

Keywords: antibacterial activity, Leptadenia hastata, infectious diseases, phytochemical screening

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