Search results for: saccadic suppression
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 276

Search results for: saccadic suppression

126 MiR-103 Inhibits Osteoblast Proliferation Mainly through Suppressing Cav 1.2 Expression in Simulated Microgravity

Authors: Zhongyang Sun, Shu Zhang, Manjiang Xie

Abstract:

Emerging evidence indicates that microRNAs (miRNAs) play important roles in modulating osteoblast function and bone formation. However, the influence of miRNA on osteoblast proliferation and the possible mechanisms underlying remain to be defined. In this study, we aimed to investigate whether miR-103 regulates osteoblast proliferation under simulated microgravity condition through regulating Cav1.2, the primary subunit of L-type voltage sensitive calcium channels (LTCCs). We first investigated the effect of simulated microgravity on osteoblast proliferation and the outcomes clearly demonstrated that the mechanical unloading inhibits MC3T3-E1 osteoblast-like cells proliferation. Using quantitative Real-Time PCR (qRT-PCR), we provided data showing that miR-103 was up-regulated in response to simulated microgravity. In addition, we observed that up-regulation of miR-103 inhibited and down-regulation of miR-103 promoted osteoblast proliferation under simulated microgravity condition. Furthermore, knocking-down or over-expressing miR-103, respectively, up- or down-regulated the level of Cav1.2 expression and LTCCs currents, suggesting that miR-103 acts as an endogenous attenuator of Cav1.2 in osteoblasts under the condition of simulated microgravity. More importantly, we showed that the effect of miR-103 on osteoblast proliferation was diminished in simulated microgravity, when co-transfecting miR-103 mimic or inhibitor with Cav1.2 siRNA. Taken together, our data suggest that miR-103 inhibits osteoblast proliferation mainly through suppression of Cav1.2 expression under simulated microgravity condition. This work may provide a novel mechanism of microgravity-induced detrimental effects on osteoblast, identifying miR-103 as a novel possible therapeutic target in bone remodeling disorders in this mechanical unloading.

Keywords: microRNA, osteoblasts, cell proliferation, Cav1.2, simulated microgravity

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125 3D Numerical Studies on Jets Acoustic Characteristics of Chevron Nozzles for Aerospace Applications

Authors: R. Kanmaniraja, R. Freshipali, J. Abdullah, K. Niranjan, K. Balasubramani, V. R. Sanal Kumar

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The present environmental issues have made aircraft jet noise reduction a crucial problem in aero-acoustics research. Acoustic studies reveal that addition of chevrons to the nozzle reduces the sound pressure level reasonably with acceptable reduction in performance. In this paper comprehensive numerical studies on acoustic characteristics of different types of chevron nozzles have been carried out with non-reacting flows for the shape optimization of chevrons in supersonic nozzles for aerospace applications. The numerical studies have been carried out using a validated steady 3D density based, k-ε turbulence model. In this paper chevron with sharp edge, flat edge, round edge and U-type edge are selected for the jet acoustic characterization of supersonic nozzles. We observed that compared to the base model a case with round-shaped chevron nozzle could reduce 4.13% acoustic level with 0.6% thrust loss. We concluded that the prudent selection of the chevron shape will enable an appreciable reduction of the aircraft jet noise without compromising its overall performance. It is evident from the present numerical simulations that k-ε model can predict reasonably well the acoustic level of chevron supersonic nozzles for its shape optimization.

Keywords: supersonic nozzle, Chevron, acoustic level, shape optimization of Chevron nozzles, jet noise suppression

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124 Strategies to Combat the Covid-19 Epidemic

Authors: Marziye Hadian, Alireza Jabbari

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Background: The World Health Organization has identified COVID-19 as a public health emergency and is urging governments to stop the virus transmission by adopting appropriate policies. In this regard, the countries have taken different approaches to cutting the chain or controlling the spread of the disease. Methods: The present study was a systematize review of publications relating to prevention strategies for covid-19 disease. The study was carried out based on the PRISMA guidelines and CASP for articles and AACODS for grey literature. Finding: The study findings showed that in order to confront the COVID-19 epidemic, in general, there are three approaches of "mitigation", "active control" and "suppression" and four strategies of "quarantine", "isolation", "social distance" as well as "lockdown" in both individual and social dimensions to deal with epidemics that the choice of each approach requires specific strategies and has different effects when it comes to controlling and inhibiting the disease. Conclusion: The only way to control the disease is to change your behavior and lifestyle. In addition to prevention strategies, use of masks, observance of personal hygiene principles such as regular hand washing and non-contact of contaminated hands with the face, as well as observance of public health principles such as control of sneezing and coughing, safe extermination of personal protective equipment, etc. have not been included in the category of prevention tools. However, it has a great impact on controlling the epidemic, especially the new coronavirus epidemic.

Keywords: novel corona virus, COVID-19, prevention tools, prevention strategies

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123 Ethanol Extract of Potentilla pradoxa Nutt Inhibits LPS-induced Inflammatory Responses via NF-κB and AP-1 Inactivation

Authors: Hae-Jun Lee, Ji-Sun Shin, Kyung-Tae Lee

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Potentilla species (Rosasease) have been used in traditional medicine to treat different ailment, disease or malady. In this study, we investigated the anti-inflammatory effects of ethanol extracts of NUTT (EPP) in lipopolysaccharide (LPS)-induced Raw 264.7 macrophages and septic mice. EPP suppressed LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production in LPS-induced Raw 264.7 macrophages. Consistent with these observations, EPP reduced the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) by downregulation of their promoter activities. EPP inhibited tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) at production and mRNA levels. Molecularly, EPP attenuated the LPS-induced transcriptional activity, and DNA-binding activity of nuclear factor-κB (NF-κB), and this was associated with a decrease of translocation and phosphorylation of p65 NF-κB by inhibiting the inhibitory κB-α (IκB-α) degradation and IκB kinase-α/β (IKK-α/β) phosphorylation. Furthermore, EPP suppressed the LPS-induced activation of activator protein-1 (AP-1) by reducing the expression of c-Fos and c-Jun in nuclear. EPP also reduced the phosphorylation of mitogen-activated protein kinase (MAPK), such as p38 MAPK and c-Jun N-terminal kinase/stress-activated protein kinase (JNK). In a sepsis model, pretreatment with EPP reduced the LPS-induced lethality. Collectively, these results suggest that the anti-inflammatory effects of EPP were associated with the suppression of NF-κB and AP-1 activation, and support its possible therapeutic role for the treatment of sepsis.

Keywords: anti-inflammation, activator protein-1, nuclear factor κB, Potentilla paradoxa Nutt

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122 The Structural System Concept of Reinforced Concrete Pier Accompanied with Friction Device plus Gap in Numerical Analysis

Authors: Angga S. Fajar, Y. Takahashi, J. Kiyono, S. Sawada

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The problem of medium span bridge bearing support in the extreme temperatures fluctuation region is deterioration in case the suppression of superstructure that sustains temperature expansion. The other hand, the behavior and the parameter of RC column accompanied with friction damping mechanism were determined successfully based on the experiment and numerical analysis. This study proposes the structural system of RC pier accompanied with multi sliding friction damping mechanism to substitute the conventional system of pier together with bearing support. In this system, the pier has monolith behavior to the superstructure with flexible small deformation to accommodate thermal expansion of the superstructure. The flexible small deformation behavior is realized by adding the gap mechanism in the multi sliding friction devices form. The important performances of this system are sufficient lateral flexibility in small deformation, sufficient elastic deformation capacity, sufficient lateral force resistance, and sufficient energy dissipation. Numerical analysis performed for this system with fiber element model. It shows that the structural system has good performance not only under small deformation due to thermal expansion of the superstructure but also under seismic load.

Keywords: RC Pier, thermal expansion, multi sliding friction device, flexible small deformation

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121 On Being a Fugitive from the State-Sponsored Witch Hunt of Homosexuals in Egypt's Media Discourse

Authors: Mahitab A. A. Mahmoud

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Despite the international community’s galvanized efforts to achieve gender equality, the Arab world still lags behind for their sustained suppression of diversity and freedoms. In Egypt, homosexuals are defamed and hunted not only by authorities but also by politicized religious institutions and media platforms. The resultant state-sponsored homophobia is reflected in media. This paper offers a critical discourse analysis of the representation of LGBTQs in Egypt’s local news articles and movies in an attempt to investigate the underlying ideology. The results reveal a clichéd portrayal of homosexuals as a social parasite that requires cleansing by the government. LGBTQs are depicted as an outcome of debauchery, unhappy marriage, sexual deviancy, deficiency of masculinity/femininity, absence of the mother and/or father figure(s), abject poverty, excessive wealth, psychiatric disorder, debased instincts, childhood sexual molestation, immorality, deviation from religion, chaos, treason, conspiracy against the regime, to name only a few. This image, which is imposed and sustained by the state, exposes homosexuals to a violation of their human rights by both the police and the society, endangers their lives, breeds intolerance, social inequality and violence, prevents healthy coexistence; and deprives them of living a normal life.

Keywords: critical discourse analysis, gender studies, homophobia, homosexuality, ideology, media studies

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120 Suppression of Immunostimulatory Function of Dendritic Cells and Prolongation of Skin Allograft Survival by Dryocrassin

Authors: Hsin-Lien Lin, Ju-Hui Fu

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Dendritic cells (DCs) are the major professional antigen-presenting cells for the development of optimal T-cell immunity. DCs can be used as pharmacological targets to screen novel biological modifiers for the treatment of harmful immune responses, such as transplantation rejection. Dryopteris crassirhizoma Nakai (Aspiadaceae) is used for traditional herbal medicine in the region of East Asia. The root of this fern plant has been listed for treating inflammatory diseases. Dryocrassin is the tetrameric phlorophenone component derived from Dryopteris. Here, we tested the immunomodulatory potential of dryocrassin on lipopolysaccharide (LPS)-stimulated activation of mouse bone marrow-derived DCs in vitro and in skin allograft transplantation in vivo. Results demonstrated that dryocrassin reduced the secretion of tumor necrosis factor-α, interleukin-6, and interleukin-12p70 by LPS-stimulated DCs. The expression of LPS-induced major histocompatibility complex class II, CD40, and CD86 on DCs was also blocked by dryocrassin. Moreover, LPS-stimulated DC-elicited allogeneic T-cell proliferation was lessened by dryocrassin. In addition, dryocrassin inhibited LPS-induced activation of IϰB kinase, JNK/p38 mitogen-activated protein kinase, as well as the translocation of NF-ϰB. Treatment with dryocrassin obviously diminished 2,4-dinitro-1-fluorobenzene- induced delayed-type hypersensitivity and prolonged skin allograft survival. Dryocrassin may be one of the potent immunosuppressive agents for transplant rejection through the destruction of DC maturation and function.

Keywords: dryocrassin, dendritic cells, immunosuppression, skin allograft

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119 TCTN2 Maintains the Transition Zone Stability and Controls the Entrance of the Ciliary Membrane Protein into Primary Cilia

Authors: Rueyhung Weng, Chia-En Huang, Jung-Chi-Liao

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The transition zone (TZ) serves as a diffusion barrier to regulate the ins and outs of the proteins recruited to the primary cilia. TCTN2 is one of the TZ proteins and its mutation causes Joubert syndrome, a serious multi-organ disease. Despite its important medical relevance, the functions of TCTN2 remain elusive. Here we created a TCTN2 gene deleted retinal pigment epithelial cells (RPE1) using CRISPR/Cas9-based genome editing technique and used this knockout line to reveal roles of TCTN2. TCTN2 knockout RPE1 cells displayed a significantly reduced ciliogenesis or a shortened primary cilium length in the cilium-remaining population. Intraflagellar transport protein IFT88 aberrantly accumulated at the tip of TCTN2 deficient cells. Guanine nucleotide exchange factor Arl13B was mostly absent from the ciliary compartment, with a small population localizing at the ciliary tip. The deficient TZ was corroborated with the mislocalization of two other TZ proteins TMEM67 and MKS1. In addition, TCTN2 deficiency induced TZ impairment led to the suppression of Sonic hedgehog signaling in response to Smoothened (Smo) agonist. Together, depletion of TCTN2 destabilizes other TZ proteins and considerably alters the localization of key transport and signaling-associated proteins, including IFT88, Arl13B, and Smo.

Keywords: CRISPR/Cas9, primary cilia, Sonic hedgehog signaling, transition zone

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118 Inhibition of Streptococcus Mutans Biofilm Development of Dental Caries In Vitro and In Vivo by Trachyspermum ammi Seeds: An Approach of Alternative Medicine

Authors: Mohd Adil, Rosina Khan, Danishuddin, Asad U. Khan

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The aim of this study was to evaluate the influence of the crude and active solvent fraction of Trachyspermum ammi on S. mutans cariogenicity, effect on expression of genes involved in biofilm formation and caries development in rats. GC–MS was carried out to identify the major components present in the crude and the active fraction of T. ammi. The crude extract and the solvent fraction exhibiting least MIC were selected for further experiments. Scanning electron microscopy was carried out to observe the effect of the extracts on S. mutans biofilm. Comparative gene expression analysis was carried out for nine selected genes. 2-Isopropyl-5-methyl-phenol was found as major compound in crude and the active fraction. Binding site of this compound within the proteins involved in biofilm formation was mapped with the help of docking studies. Real-time RT-PCR analyses revealed significant suppression of the genes involved in biofilm formation. All the test groups showed reduction in caries (smooth surface as well as sulcal surface caries) in rats. Moreover, it also provides new insight to understand the mechanism influencing biofilm formation in S. mutans. Furthermore, the data suggest the putative cariostatic properties of T. Ammi and hence can be used as an alternative medicine to prevent caries infection.

Keywords: bio-film, Streptococcus mutans, dental caries, bio-informatic

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117 The 5S Responses of Obese Teenagers in Verbal Bullying

Authors: Alpha Bolinao, Francine Rose De Castro, Jessie Kate Lumba, Raztine Mae Paeste, Hannah Grace Tosio

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The present study aimed to know the role of verbal bullying in the lives of obese teenagers exposed to it. The study employed a qualitative design specifically the phenomenological approach that focuses on the obese teenagers’ verbal bullying experiences. The study also used the social constructivism approach wherein it described the obese teenagers’ verbal bullying experiences as they interact with the social world. Through purposive and referral sampling technique, the researchers were able to choose twelve (12) respondents from different schools around the City of Manila, enrolled in the School Year 2015-2016, ages 16-21 years old, has experienced verbal bullying for the last ten (10) years and with the Body Mass Index (BMI) of equal to or greater than 30. Upon the consent of the respondents, ethical considerations were ensured. In-depth one (1) hour interviews were guided by the researchers’ aide memoir. The recorded interviews were transcribed into a field text and the responses were thoroughly analyzed through Thematic Analysis and Kelly’s Repertory Grid. It was found that the role of verbal bullying in the lives of obese teenagers exposed to it is a process and is best described through a syringe, or the 5S Responses of Obese Teenagers in Bullying, with five conceptual themes which also signify the experiences and the process that obese teenagers have gone through after experiencing verbal bullying. The themes conceptualized were: Suffering, self-doubt, suppression, self-acceptance and sanguineness. This paper may serve as a basis for a counseling program to help the obese teenagers cope with their bullying experiences.

Keywords: obesity, obese teenagers, bullying, experiences

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116 Acceptance and Commitment Therapy as a Treatment for Alcohol Use Disorders in South Korea

Authors: Kim Eunha

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This study examined a group-based intervention for alcohol use disorders based on the principles of acceptance and commitment therapy (ACT) in patients (N=22; 63.7% female; M = 38.2 years old; 100% South Korean) in a residential alcohol addiction treatment program. Patients were randomly assigned to either ACT group (receiving the ACT intervention) or control group (receiving treatment as usual). The ACT intervention consisted of four 2-hr group sessions scheduled during two weeks. The first session focused on the negative effects of suppression and avoidance, and a rationale for defusion and acceptance using several of the well-known ACT metaphors (e.g., Two Scales Metaphor, Man in the Hole). The second session taught defusion and acceptance skills through such exercises as mindfulness, cutting a sour fruit, naming one’s thoughts, and physicalizing. The third session included another mindfulness exercise and encouraged the participants to identify their values and set up life goals. The last session included more discussion on values and life goals, especially related to family and intimacy. The effects of the interventions were assessed using intent-to-treat analyses. The ACT interventions resulted in smaller immediate gains in motivation to stay sober and reductions in depression, anxiety, and experiential avoidance. In addition, at a 2-month follow up, those who attended the ACT group reported a lower average level of alcohol consumption and higher treatment attendance compared to the control group. These preliminary findings suggest that additional treatment and testing of ACT for alcohol use disorders will be crucial.

Keywords: acceptance and commitment therapy, alcohol use disorders, defusion, values

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115 Anti-inflammatory and Antioxidant Activity of Heliotropium indicum Linn. Used for Cancer Patients Treatment

Authors: Jitpisute Chunthorng-Orn, Thana Juckmeta, Onmanee Prajuabjinda, Arunporn Itharat

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Inflammation and oxidative stress work together to produce symptoms in cancer patients. The whole part of it is used as a preparation to treat cancer patients in Khampramong temple which has been a place of treatment and palliative care for cancer patients since 2005. Thus, the objective of this study was to investigate anti-inflammatory and antioxidant activities of Heliotropium indicum extracts. Dried plant materials were extracted in a similar manner to those practiced by the Khampramong Temple i.e. maceration in 95% ethanol and boiling in water. For anti-inflammation activity, both extracts were tested for suppression of nitric oxide (NO) production in LPS-induced RAW 264.7 cells. They were also tested for antioxidant activity by DPPH radical scavenging assay. This study found that the ethanolic extract of Heliotropium indicum exhibited higher inhibitory activity of NO release than Indomethacin as a positive control (IC50 value of 24.17±2.12 and 34.67±6.23 μg/mL, respectively). For DPPH radical scavenging assay, the ethanolic extract also exhibited antioxidant activity but less than BHT as a antioxidant compound (EC50 values = 28.91±4.26 and 13.08±0.29 μg/mL, respectively). In contrast, its water extract had no inhibitory activity on NO release (IC50 > 100 μg/mL) and no inhibitory activity on DPPH radicals (EC50 values > 100 μg/mL). The results showed correlation between anti-inflammation and antioxidant activity and these results also support using this plant to treat cancer patients.

Keywords: Heliotropium indicum, RAW 264.7, DPPH, Khampramong Temple

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114 The Efficacy of Andrographis paniculata and Chromolaena odorata Plant Extract against Malaria Parasite

Authors: Funmilola O. Omoya, Abdul O. Momoh

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Malaria constitutes one of the major health problems in Nigeria. One of the reasons attributed for the upsurge was the development of resistance of Plasmodium falciparum and the emergence of multi-resistant strains of the parasite to anti-malaria drugs. A continued search for other effective, safe and cheap plant-based anti-malaria agents thus becomes imperative in the face of these difficulties. The objective of this study is therefore to evaluate the in vivo anti-malarial efficacy of ethanolic extracts of Chromolaena odorata and Androgaphis paniculata leaves. The two plants were evaluated for their anti-malaria efficacy in vivo in a 4-day curative test assay against Plasmodium berghei strain in mice. The group treated with 500mg/ml dose of ethanolic extract of A. paniculata plant showed parasite suppression with increase in Packed Cell Volume (PCV) value except day 3 which showed a slight decrease in PCV value. During the 4-day curative test, an increase in the PCV values, weight measurement and zero count of Plasmodium berghei parasite values was recorded after day 3 of drug administration. These results obtained in group treated with A. paniculata extract showed anti-malarial efficacy with higher mortality rate in parasitaemia count when compared with Chromolaena odorata group. These results justify the use of ethanolic extracts of A. paniculata plant as medicinal herb used in folklore medicine in the treatment of malaria.

Keywords: anti-malaria, curative, plant-based anti-malaria agents, biology

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113 The Effects of Root Zone Supply of Aluminium on Vegetative Growth of 15 Groundnut Cultivars Grown in Solution Culture

Authors: Mosima M. Mabitsela

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Groundnut is preferably grown on light textured soils. Most of these light textured soils tend to be highly weathered and characterized by high soil acidity and low nutrient status. One major soil factor associated with infertility of acidic soils that can negatively depress groundnut yield is aluminium (Al) toxicity. In plants Al toxicity damages root cells, leading to inhibition of root growth as a result of the suppression of cell division, cell elongation and cell expansion in the apical meristem cells of the root. The end result is that roots become stunted and brittle, root hair development is poor, and the root apices become swollen. This study was conducted to determine the effects of aluminium (Al) toxicity on a range of groundnut varieties. Fifteen cultivars were tested in incremental aluminum (Al) supply in an ebb and flow solution culture laid out in a randomized complete block design. There were six aluminium (Al) treatments viz. 0 µM, 1 µM, 5.7 µM, 14.14 µM, 53.18 µM, and 200 µM. At 1 µM there was no inhibitory effect on the growth of groundnut. The inhibition of groundnut growth was noticeable from 5.7 µM to 200 µM, where the severe effect of aluminium (Al) stress was observed at 200 µM. The cultivars varied in their response to aluminium (Al) supply in solution culture. Groundnuts are one of the most important food crops in the world, and its supply is on a decline due to the light-textured soils that they thrive under as these soils are acidic and can easily solubilize aluminium (Al) to its toxic form. Consequently, there is a need to develop groundnut cultivars with high tolerance to soil acidity.

Keywords: aluminium toxicity, cultivars, reduction, root growth

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112 Optimum Design of Hybrid (Metal-Composite) Mechanical Power Transmission System under Uncertainty by Convex Modelling

Authors: Sfiso Radebe

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The design models dealing with flawless composite structures are in abundance, where the mechanical properties of composite structures are assumed to be known a priori. However, if the worst case scenario is assumed, where material defects combined with processing anomalies in composite structures are expected, a different solution is attained. Furthermore, if the system being designed combines in series hybrid elements, individually affected by material constant variations, it implies that a different approach needs to be taken. In the body of literature, there is a compendium of research that investigates different modes of failure affecting hybrid metal-composite structures. It covers areas pertaining to the failure of the hybrid joints, structural deformation, transverse displacement, the suppression of vibration and noise. In the present study a system employing a combination of two or more hybrid power transmitting elements will be explored for the least favourable dynamic loads as well as weight minimization, subject to uncertain material properties. Elastic constants are assumed to be uncertain-but-bounded quantities varying slightly around their nominal values where the solution is determined using convex models of uncertainty. Convex analysis of the problem leads to the computation of the least favourable solution and ultimately to a robust design. This approach contrasts with a deterministic analysis where the average values of elastic constants are employed in the calculations, neglecting the variations in the material properties.

Keywords: convex modelling, hybrid, metal-composite, robust design

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111 In silico Designing and Insight into Antimalarial Potential of Chalcone-Quinolinylpyrazole Hybrids by Preclinical Study in Mice

Authors: Deepika Saini, Sandeep Jain, Ajay Kumar

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The quinoline scaffold is one of the most widely studied in the discovery of derivatives with various heterocyclic moieties due to its potential antimalarial activities. In the present study, a chalcone series of quinoline derivatives clubbed with pyrazole were synthesized to evaluate their antimalarial property by in vitro schizont maturation inhibition assay against both chloroquine sensitive, 3D7 and chloroquine resistant, RKL9 strain of Plasmodium falciparum. Further, top five compounds were studied for in vivo preclinical study for antimalarial potential against P. berghei in Swiss albino mice. To understand the mechanism of synthesized analogues, they were screened computationally by molecular docking techniques. Compounds were docked into the active site of a protein receptor, Plasmodium falciparum Cysteine Protease Falcipain-2. The compounds were successfully synthesized, and structural confirmation was performed by FTIR, 1H-NMR, mass spectrometry and elemental analysis. In vitro study suggested that the compounds 5b, 5g, 5l, 5s and 5u possessed best antimalarial activity and further tested for in vivo screening. Compound 5u (CH₃ on both rings) with EC₅₀ 0.313 & 0.801 µg/ml against CQ-S & CQ-R strains of P. falciparum respectively and 78.01% suppression of parasitemia. The molecular docking studies of the compounds helped in understanding the mechanism of action against falcipain-2. The present study reveals the binding signatures of the synthesized ligands within the active site of the protein, and it explains the results from in vitro study in their EC₅₀ values and percentage parasitemia.

Keywords: antimalarial activity, chalcone, docking, quinoline

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110 Design Optimization of Chevron Nozzles for Jet Noise Reduction

Authors: E. Manikandan, C. Chilambarasan, M. Sulthan Ariff Rahman, S. Kanagaraj, V. R. Sanal Kumar

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The noise regulations around the major airports and rocket launching stations due to the environmental concern have made jet noise a crucial problem in the present day aero-acoustics research. The three main acoustic sources in jet nozzles are aerodynamics noise, noise from craft systems and engine and mechanical noise. Note that the majority of engine noise is due to the jet noise coming out from the exhaust nozzle. The previous studies reveal that the potential of chevron nozzles for aircraft engines noise reduction is promising owing to the fact that the jet noise continues to be the dominant noise component, especially during take-off. In this paper parametric analytical studies have been carried out for optimizing the number of chevron lobes, the lobe length and tip shape, and the level of penetration of the chevrons into the flow over a variety of flow conditions for various aerospace applications. The numerical studies have been carried out using a validated steady 3D density based, SST k-ω turbulence model with enhanced wall functions. In the numerical study, a fully implicit finite volume scheme of the compressible, Navier–Stokes equations is employed. We inferred that the geometry optimization of an environmental friendly chevron nozzle with a suitable number of chevron lobes with aerodynamically efficient tip contours for facilitating silent exit flow will enable a commendable sound reduction without much thrust penalty while comparing with the conventional supersonic nozzles with same area ratio.

Keywords: chevron nozzle, jet acoustic level, jet noise suppression, shape optimization of chevron nozzles

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109 Voting Behavior in an Era of Turbulent Race Relations: Revisiting Church Attendance and Turnout

Authors: JoVontae Butts

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A central and enduring theme in the study of American politics is political participation, which indicates the health of a democracy, citizen buy-in, and fair political representation. Though voting push factors have been thoroughly researched and are becoming better understood, the effect of those same push factors often varies for marginalized people. Black voters begun to cast votes at a steadily increasing rate following the 1996 election, gradually growing to its highest level in the 2012 presidential election, even surpassing white voter participation rates. The thirty-year growth period of Black voter engagement concluded in the 2016 election, with the number of participating Black voters stumbling by approximately 7% while other demographics remained roughly the same. Theories for the shift in Black voter behavior range from vote suppression to discouragement due to Barack Obama’s concluding tenure in office. Furthermore, Black voter engagement rebounded in the 2020 election, leaving turnout and race scholars to speculate even further, predicting that disapproval of Trump energized the Black voter bloc. Though there is much conjecture regarding the changes in Black voter behavior, there is truly little empirical evidence to vet those suppositions. This study engages and quantifies speculations for the changes in Black voter engagement in recent elections using 2016 and 2020 American National Election Studies Pilot Study data. Additionally, this study expands upon McGregor’s theory of political hypervigilance by exploring differences in political engagement for church-attending Black voters and those that do not.

Keywords: race, religion, evangelicalism, political engagement

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108 YHV-Responsive Gene Expression under the Influence of PmRelish Regulation

Authors: Suwattana Visetnan, Premruethai Supungul, Sureerat Tang, Ikuo Hirono, Anchalee Tassanakajon, Vichien Rimphanitchayakit

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In animals, infection by Gram-negative bacteria and certain viruses activates the Imd signaling pathway wherein the a NF-κB transcription factor, Relish, is a key regulatory protein for the synthesis of antimicrobial proteins. Infection by yellow head virus (YHV) activates the Imd pathway. To investigate the expression of genes involved in YHV infection and under the influence of PmRelish regulation, RNA interference and suppression subtractive hybridization (SSH) are employed. The genes in forward library expressed in shrimp after YHV infection and under the activity of PmRelish were obtained by subtracting the cDNAs from YHV-infected and PmRelish-knockdown shrimp with cDNAs from YHV-infected shrimp. Opposite subtraction gave a reverse library whereby an alternative set of genes under YHV infection and no PmRelish expression was obtained. Sequencing of 252 and 99 cDNA clones from the respective forward and reverse libraries were done and annotated through blast search against the GenBank sequences. Genes involved in defense and homeostasis were abundant in both libraries, 31% and 23% in the forward and reverse libraries, respectively. They were predominantly antimicrobial proteins, proteinases and proteinase inhibitors. The expression of antimicrobial protein genes, ALFPm3, crustinPm1, penaeidin3 and penaeidin5 were tested under PmRelish silencing and Gram-negative bacterium V. harveyi infection. Together with the results previously reported, the expression of penaeidin5 and also penaeidin3 but not ALFPm3 and crustinPm1 were under the regulation of PmRelish in the Imd pathway.

Keywords: relish, yellow head virus, penaeus monodon, antimicrobial proteins

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107 Design and Performance Comparison of Metamaterial Based Antenna for 4G/5G Mobile Devices

Authors: Jalal Khan, Daniyal Ali Sehrai, Shakeel Ahmad

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This paper presents the design and performance evaluation of multiband metamaterial based antenna operating in the 3.6 GHz (4G), 14.33 GHz, and 28.86 GHz (5G) frequency bands, for future mobile and handheld devices. The radiating element of the proposed design is made up of a conductive material supported by a 1.524 mm thicker Rogers-4003 substrate, having a relative dielectric constant and loss tangent of 3.55 and 0.0027, respectively. The substrate is backed by truncated ground plane. The future mobile communication system is based on higher frequencies, which are highly affected by the atmospheric conditions. Therefore, to overcome the path loss problem, essential enhancements and improvements must be made in the overall performance of the antenna. The traditional ground plane does not provide the in-phase reflection and surface wave suppression due to which side and back lobes are produced. This will affect the antenna performance in terms of gain and efficiency. To enhance the overall performance of the antenna, a metamaterial acting as a high impedance surface (HIS) is used as a reflector in the proposed design. The simulated gain of the metamaterial based antenna is enhanced from {2.76-6.47, 4.83-6.71 and 7.52-7.73} dB at 3.6, 14.33 and 28.89 GHz, respectively relative to the gain of the antenna backed by a traditional ground plane. The proposed antenna radiated efficiently with a radiated efficiency (>85 %) in all the three frequency bands with and without metamaterial surface. The total volume of the antenna is (L x W x h=45 x 40 x 1.524) mm3. The antenna can be potentially used for wireless handheld devices and mobile terminal. All the simulations have been performed using the Computer Simulation Technology (CST) software.

Keywords: CST MWS, fourth generation/fifth generation, 4G/5G, high gain, multiband, metamaterial

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106 Study of Age-Dependent Changes of Peripheral Blood Leukocytes Apoptotic Properties

Authors: Anahit Hakobjanyan, Zdenka Navratilova, Gabriela Strakova, Martin Petrek

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Aging has a suppressive influence on human immune cells. Apoptosis may play important role in age-dependent immunosuppression and lymphopenia. Prevention of apoptosis may be promoted by BCL2-dependent and BCL2-independent manner. BCL2 is an antiapoptotic factor that has an antioxidative role by locating the glutathione at mitochondria and repressing oxidative stress. STAT3 may suppress apoptosis in BCL2-independent manner and promote cell survival blocking cytochrome-c release and reducing ROS production. The aim of our study was to estimate the influence of aging on BCL2-dependent and BCL2-independent prevention of apoptosis via measurement of BCL2 and STAT3 mRNAs expressions. The study was done on Armenian population (2 groups: 37 healthy young (mean age±SE; min/max age, male/female: 37.6±1.1; 20/54, 15/22), 28 healthy aged (66.7±1.5; 57/85, 12/16)). mRNA expression in peripheral blood leukocytes (PBL) was determined by RT-PCR using PSMB2 as the reference gene. Statistical analysis was done with Graph-Pad Prism 5; P < 0.05 considered as significant. The expression of BCL2 mRNA was lower in aged group (0.199) compared with young ones (0.643)(p < 0.01). Decrease expression was also recorded for female and male subgroups (p < 0.01). The expression level of STAT3 mRNA was increased (young, 0.228; aged, 0.428) (p < 0.05) during aging (in the whole age group and male/female subgroups). Decreased level of BCL2 mRNA may indicate about the suppression of BCL2-dependent prevention of apoptosis during aging in peripheral blood leukocytes. At the same time increased the level of STAT3 may suggest about activation of BCL2-independent prevention of apoptosis during aging.

Keywords: BCL2, STAT3, aging, apoptosis

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105 Field Application of Trichoderma Harzianum for Biological Control of Root-Knot Nematodes in Summer Tomatoes

Authors: Baharullah Khattak, Saifullah

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To study the efficacy of the selected Trichoderma isolates, field trials were conducted in the root-knot nematode-infested areas of Dargai and Swat, Pakistan. Four isolates of T. harzianum viz, Th-1, Th-2, Th-9 and Th-15 were tested against root knot nematodes on summer tomatoes under field conditions. The T. harzianum isolates, grown on wheat grains substrate, were applied @ 8 g plant-1, either alone or in different combinations. Root weight of tomato plants was reduced Th-9 as compared to 26.37 g in untreated control. Isolate Th-1 was found to enhance shoot and root lengths to the maximum levels of 78.76 cm and 19.59 cm, respectively. Tomato shoot weight was significantly increased (65.36g) in Th-1-treated plots as compared to 49.66 g in control. Maximum (156) number of flowers plant-1 and highest (48.18%) fruit set plant-1 was observed in Th-1 treated plots, while there were 87 flowers and 35.50% fruit set in the untreated control. Maximum fruit weight (70.97 g) plant-1 and highest (17.99 t ha-1) marketable yield were recorded in the treatments where T. harzianum isolate Th-1 was used, in comparison to 51.33 g tomato fruit weight and 9.90 t ha-1 yield was noted in the control plots. It was observed that T. harzianum isolates significantly reduced the nematode populations. The fungus enhanced plant growth and yield in all the treated plots. Jabban isolate (Th-1) was found as the most effective in nematode suppression followed by Shamozai (Th-9) isolate. It was concluded from the present findings that T. harzianum has a potential bio control capability against root-knot nematodes.

Keywords: biological control, Trichoderma harzianum, root-knot nematode, meloidogyne

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104 An Investigation of Suppression in Mid-19th Century Japan: Case Study of the 1855 Catfish Prints as a Product of Censorship

Authors: Vasanth Narayanan

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The mid-nineteenth century saw the Japanese elite and townsfolk alike undergo the now-infamous Ansei Edo earthquakes. The quakes decimated Japan in the final decades of the Tokugawa Era and, perhaps more consequentially, birthed a new genre of politically inspired artwork, the most notable of which are the namazu-e. This essay advocates an understanding of the 1855 Catfish Prints (namazu-e) that prioritizes the function of iconography and anthropomorphic deity in shaping the namazu-e into a wholly political experience that makes the censorship of the time part of its argument. The visual program is defined as the creation of a politically profitable experience, crafted through the union of explicit religion, highly masked commentary, and the impositions of censorship. The strategies by which the works are designed, in the face of censorship, to engage a less educated, pedestrian audience with its theme, including considerations of iconography, depictions of the working class, anthropomorphism, and the relationship between textual and visual elements, are discussed herein. The essay then takes up the question of the role of tense Japan–United States relations in fostering censorship and as a driver of the production of namazu-e. It is ultimately understood that the marriage of hefty censorship protocol, the explicitly religious medium, and inimical sentiment towards United States efforts at diplomacy renders the production of namazu-e an offspring of the censorship and deeply held frustrations of the time, cementing its status as a primitive form of peaceful protest against a seemingly apathetic government.

Keywords: Japan, Ansei Earthquake, Namazu, prints, censorship, religion

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103 Rapid Weight Loss in Athletes: A Look at Suppressive Effects on Immune System

Authors: Nazari Maryam, Gorji Saman

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For most competitions, athletes usually engage in a process called rapid weight loss (RWL) and subsequent rapid weight gain (RWG) in the days preceding the event. Besides the perfection of performance, weight regulation mediates a self-image of being “a real athlete” which is mentally important as a part of the pre-competition preparation. This feeling enhances the focus and commitment of the athlete. There is a large body of evidence that weight loss, particularly in combat sports, results in several health benefits. However, intentional weight loss beyond normal levels might have unknown negative special effects on the immune system. As the results show, a high prevalence (50%) of RWL is happening among combat athletes. It seems that energy deprivation and intense exercise to reach RWL results in altered blood cell distribution through modification of body composition that, in turn, changes B and T-Lymphocyte and/or CD4 T-Helper response. Moreover, it may diminish IgG antibody levels and modulate IgG glycosylation after this course. On the other hand, some studies show suppression of signaling and regulation of IgE antibody and chemokine production are responsible for immunodeficiency following a period of low-energy availability. Some researchers hypothesize that severe glutamine depletion, which occurs during exercise and calorie restriction, is responsible for this immune system weakness. However, supplementation by this amino acid is not prescribed yet. Therefore, weight loss is achieved not only through chronic strategies (body fat losses) but also through acute manipulations prior to competition should be supervised by a sports nutritionist to minimize side effects on the immune system and other body systems.

Keywords: athletes, immune system, rapid weight loss, weight loss strategies

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102 Sequential Release of Dual Drugs Using Thermo-Sensitive Hydrogel for Tumor Vascular Inhibition and to Enhance the Efficacy of Chemotherapy

Authors: Haile F. Darge, Hsieh C. Tsai

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The tumor microenvironment affects the therapeutic outcomes of cancer disease. In a malignant tumor, overexpression of vascular endothelial growth factor (VEGF) provokes the production of pathologic vascular networks. This results in a hostile tumor environment that hinders anti-cancer drug activities and profoundly fuels tumor progression. In this study, we develop a strategy of sequential sustain release of the anti-angiogenic drug: Bevacizumab(BVZ), and anti-cancer drug: Doxorubicin(DOX) which had a synergistic effect on cancer treatment. Poly (D, L-Lactide)- Poly (ethylene glycol) –Poly (D, L-Lactide) (PDLLA-PEG-PDLLA) thermo-sensitive hydrogel was used as a vehicle for local delivery of drugs in a single platform. The in vitro release profiles of the drugs were investigated and confirmed a relatively rapid release of BVZ (73.56 ± 1.39%) followed by Dox (61.21 ± 0.62%) for a prolonged period. The cytotoxicity test revealed that the copolymer exhibited negligible cytotoxicity up to 2.5 mg ml-1 concentration on HaCaT and HeLa cells. The in vivo study on Hela xenograft nude mice verified that hydrogel co-loaded with BVZ and DOX displayed the highest tumor suppression efficacy for up to 36 days with pronounce anti-angiogenic effect of BVZ and with no noticeable damage on vital organs. Therefore, localized co-delivery of anti-angiogenic drug and anti-cancer drugs by the hydrogel system may be a promising approach for enhanced chemotherapeutic efficacy in cancer treatment.

Keywords: anti-angiogenesis, chemotherapy, controlled release, thermo-sensitive hydrogel

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101 Measurements and Predictions of Hydrates of CO₂-rich Gas Mixture in Equilibrium with Multicomponent Salt Solutions

Authors: Abdullahi Jibril, Rod Burgass, Antonin Chapoy

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Carbon dioxide (CO₂) is widely used in reservoirs to enhance oil and gas production, mixing with natural gas and other impurities in the process. However, hydrate formation frequently hinders the efficiency of CO₂-based enhanced oil recovery, causing pipeline blockages and pressure build-ups. Current hydrate prediction methods are primarily designed for gas mixtures with low CO₂ content and struggle to accurately predict hydrate formation in CO₂-rich streams in equilibrium with salt solutions. Given that oil and gas reservoirs are saline, experimental data for CO₂-rich streams in equilibrium with salt solutions are essential to improve these predictive models. This study investigates the inhibition of hydrate formation in a CO₂-rich gas mixture (CO₂, CH₄, N₂, H₂ at 84.73/15/0.19/0.08 mol.%) using multicomponent salt solutions at concentrations of 2.4 wt.%, 13.65 wt.%, and 27.3 wt.%. The setup, test fluids, methodology, and results for hydrates formed in equilibrium with varying salt solution concentrations are presented. Measurements were conducted using an isochoric pressure-search method at pressures up to 45 MPa. Experimental data were compared with predictions from a thermodynamic model based on the Cubic-Plus-Association equation of state (EoS), while hydrate-forming conditions were modeled using the van der Waals and Platteeuw solid solution theory. Water activity was evaluated based on hydrate suppression temperature to assess consistency in the inhibited systems. Results indicate that hydrate stability is significantly influenced by inhibitor concentration, offering valuable guidelines for the design and operation of pipeline systems involved in offshore gas transport of CO₂-rich streams.

Keywords: CO₂-rich streams, hydrates, monoethylene glycol, phase equilibria

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100 Barnard Feature Point Detector for Low-Contractperiapical Radiography Image

Authors: Chih-Yi Ho, Tzu-Fang Chang, Chih-Chia Huang, Chia-Yen Lee

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In dental clinics, the dentists use the periapical radiography image to assess the effectiveness of endodontic treatment of teeth with chronic apical periodontitis. Periapical radiography images are taken at different times to assess alveolar bone variation before and after the root canal treatment, and furthermore to judge whether the treatment was successful. Current clinical assessment of apical tissue recovery relies only on dentist personal experience. It is difficult to have the same standard and objective interpretations due to the dentist or radiologist personal background and knowledge. If periapical radiography images at the different time could be registered well, the endodontic treatment could be evaluated. In the image registration area, it is necessary to assign representative control points to the transformation model for good performances of registration results. However, detection of representative control points (feature points) on periapical radiography images is generally very difficult. Regardless of which traditional detection methods are practiced, sufficient feature points may not be detected due to the low-contrast characteristics of the x-ray image. Barnard detector is an algorithm for feature point detection based on grayscale value gradients, which can obtain sufficient feature points in the case of gray-scale contrast is not obvious. However, the Barnard detector would detect too many feature points, and they would be too clustered. This study uses the local extrema of clustering feature points and the suppression radius to overcome the problem, and compared different feature point detection methods. In the preliminary result, the feature points could be detected as representative control points by the proposed method.

Keywords: feature detection, Barnard detector, registration, periapical radiography image, endodontic treatment

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99 Localization of Pyrolysis and Burning of Ground Forest Fires

Authors: Pavel A. Strizhak, Geniy V. Kuznetsov, Ivan S. Voytkov, Dmitri V. Antonov

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This paper presents the results of experiments carried out at a specialized test site for establishing macroscopic patterns of heat and mass transfer processes at localizing model combustion sources of ground forest fires with the use of barrier lines in the form of a wetted lay of material in front of the zone of flame burning and thermal decomposition. The experiments were performed using needles, leaves, twigs, and mixtures thereof. The dimensions of the model combustion source and the ranges of heat release correspond well to the real conditions of ground forest fires. The main attention is paid to the complex analysis of the effect of dispersion of water aerosol (concentration and size of droplets) used to form the barrier line. It is shown that effective conditions for localization and subsequent suppression of flame combustion and thermal decomposition of forest fuel can be achieved by creating a group of barrier lines with different wetting width and depth of the material. Relative indicators of the effectiveness of one and combined barrier lines were established, taking into account all the main characteristics of the processes of suppressing burning and thermal decomposition of forest combustible materials. We performed the prediction of the necessary and sufficient parameters of barrier lines (water volume, width, and depth of the wetted lay of the material, specific irrigation density) for combustion sources with different dimensions, corresponding to the real fire extinguishing practice.

Keywords: forest fire, barrier water lines, pyrolysis front, flame front

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98 Characterization of Biogenic Silver Nanoparticles by Salvadora persica Leaves Extract and its Application Against Some MDR Pathogens E. Coli and S. Aureus

Authors: Mudawi M. Nour

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Background: Now a days, the multidisciplinary scientific research conception in the field of nanotechnology has witnessed development with regard to the numerous applications and synthesis of nanomaterials. Objective: The current investigation has been conducted with the main focus on the green synthesis of silver nanoparticles from the leaves of Salvadora persica and its antibacterial activity against MDR pathogens E. coli and S. aureus. Methodology: Silver nanoparticles (AgNPs) were prepared after addition of aqueous extract of Salvadora persica leaves. The UV-Vis spectrophotometer, Transmission Electron Microscopy (TEM), zeta potential and Scanning Electron Microscopy (SEM) were employed to detect the particle size and morphology, besides Fourier transform infra-red spectrometer (FTIR) analysis was performed to determine the capping and stabilizing agents in the extract. Antibacterial assay for the biogenic AgNPs was conducted against E. coli and S. aureus. Results: Color change of the mixture from yellow to dark brown is the first indication to AgNPs formation. Furthermore, 420 nm was the peak value for UV-Vis spectroscopy absorption of the mixture. Besides, TEM and SEM micrographs showed wide variability in the diameter of smaller NPs aggregated together with spherical shapes, and zeta sizer showed about 153.3 nm as an average size of nanoparticles. Microbial suppression was noticed for the tested microorganisms. Furthermore, with the help of FTIR analysis, the biomolecules that act as capping and stabilizing agents of AgNPs are proteins and phenols present in the plant extract. Conclusion: Salvadora persica leaves extract act as a reducing and stabilizing agent for the synthesis of AgNPs, keeping its ability to suppress the MDR pathogen.

Keywords: green synthesis, FTIR, MDR pathogen, salvadora persica

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97 Effect of CYP2B6 c.516G>T and c.983T>C Single Nucleotide Polymorphisms on Plasma Nevirapine Levels in Zimbabwean HIV/AIDS Patients

Authors: Doreen Duri, Danai Zhou, Babil Stray-Pedersen, Collet Dandara

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Given the high prevalence of HIV/AIDS in sub-Saharan Africa, and the elusive search for a cure, understanding the pharmacogenetics of currently used drugs is critical in populations from the most affected regions. Compared to Asian and Caucasian populations, African population groups are more genetically diverse, making it difficult to extrapolate findings from one ethnic group to another. This study aimed to investigate the role of genetic variation in CYP2B6 (c.516G>T and c.983T>C) single nucleotide polymorphisms on plasma nevirapine levels among HIV-infected adult Zimbabwean patients. Using a cross-sectional study, patients on nevirapine-containing HAART, having reached steady state (more than six weeks on treatment) were recruited to participate. Blood samples were collected after patients provided consent and samples were used to extract DNA for genetic analysis or to measure plasma nevirapine levels. Genetic analysis was carried out using PCR and RFLP or Snapshot for the two single nucleotide polymorphisms; CYP2B6 c.516G>T and c.983T>C, while LC-MS/MS was used in analyzing nevirapine concentration. CYP2B6 c.516G>T and c.983T>C significantly predicted plasma nevirapine concentration with the c.516T and c.983T being associated with elevated plasma nevirapine concentrations. Comparisons of the variant allele frequencies observed in this group to those reported in some African, Caucasian and Asian populations showed significant differences. We conclude that pharmacogenetics of nevirapine can be creatively used to determine patients who are likely to develop nevirapine-associated side effects as well as too low plasma concentrations for viral suppression.

Keywords: allele frequencies, genetically diverse, nevirapine, single nucleotide polymorphism

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