Search results for: molecular catalyst
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2809

Search results for: molecular catalyst

949 Analysis of Cannabinoid and Cannabidiol Affinity with GABRA1

Authors: Hamid Hossein Khezri, Afsaneh Javdani-Mallak

Abstract:

Fast inhibitory neurotransmission in the mammalian nervous system is largely mediated by GABAA receptors, chloride-selective members of the superfamily of pentameric Cys-loop receptors. Cannabidiol (CBD) is one of the members of cannabinoid compounds found in cannabis. CBD and Cannabinol (CBN), as the other extract of plant Cannabis, were able to reduce myofascial pain in rats with immunosuppressive and anti-inflammatory activities. In this study, we accomplished protein-protein BLAST and the sequence was found to be for Gamma-aminobutyric acid receptor subunit alpha-1 (GBRA1) chain A and its 3D structure was subsequently downloaded from Protein Data Bank. The structures of the ligands cannabinol and cannabidiol were obtained from PubChem. After a necessary process of the obtained files, AutoDock Vina was used to performing molecular docking. Docking between the ligands and GBRA1 chain A revealed that cannabinol has a higher affinity to GBRA1 (binding energy = -7.5 kcal/mol) compared to cannabidiol (binding energy = -6.5 kcal/mol). Furthermore, cannabinol seems to be able to interact with 10 residues of the protein, out of which 3 are in the neurotransmitter-gated ion-channel transmembrane domain of GBRA1, whereas cannabidiol interacts with two other residues. Although the results of this project do not indicate the activating /or inhibitory capability of the studied compounds, it suggests that cannabinol can act as a relatively strong ligand for GBRA1.

Keywords: protein-ligand docking, cannabinol, cannabidiol, GBRA1

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948 An Antifungal Peptide from Actinobacteria (Streptomyces Sp. TKJ2): Isolation and Partial Characterization

Authors: Abdelaziz Messis, Azzeddine Bettache, Nawel Boucherba, Said Benallaoua, Mouloud Kecha

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Actinobacteria are of special biotechnological interest since they are known to produce chemically diverse compounds with a wide range of biological activity. This distinct clade of Gram-positve bacteria include some of the key antibiotic producers and are also sources of several bioactive compounds, established commercially a newly filamentous bacteria was recovered from Tikjda forest soil (Algeria) for its high antifungal activity against various pathogenic and phytopathogenic fungi. The nucleotide sequence of the 16S rRNA gene (1454 pb) of Streptomyces sp. TKJ2 exhibited close similarity (99 %) with other Streptomyces16S rRNA genes. Antifungal metabolite production of Streptomyces sp TKJ2 was evaluated using six different fermentation media. The extracellular products contained potent antifungal agents. Antifungal protein produced by Streptomyces sp. TKJ2 on PCA medium has been purified by ammonium sulfate precipitation, SPE column chromatography and high-performance liquid chromatography in a reverse-phase column. The UV chromatograms of the active fractions obtained at 214 nm by NanoLC-ESI-MS/MS have different molecular weights. The F20 Peptidic fraction obtained from culture filtrat of Streptomyces sp. TKJ2 precipitated at 30% of ammonium sulfate was selected for analysis by infusion ESI-MS which yielded a singly charged ion mass of 437.17 Da.

Keywords: actinobacteria, antifungal protein, chromatography, Streptomyces

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947 Surface Segregation-Inspired Design for Bimetallic Nanoparticle Catalysts

Authors: Yaxin Tang, Mingao Hou, Qian He, Guangfu Luo

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Bimetallic nanoparticles serve as a promising class of catalysts with tunable properties suitable for diverse catalytic reactions, yet a comprehensive understanding of their actual structures under operating conditions and the optimal design principles remains largely elusive. In this study, we unveil a prevalent surface segregation phenomenon in nearly 100 platinum-group-element-based bimetallic nanoparticles through first principles-based molecular dynamics simulations. Our findings highlight that two components in a nanoparticle with relatively lower surface energy tend to segregate to the surface. Motivated by this discovery, we propose a deliberate exploitation of surface segregation in designing bimetallic nanoparticle catalysts, aiming for heightened stability and reduced consumption of precious metals. To validate this strategy, we further investigate 36 platinum-based bimetallic nanoparticles for propane dehydrogenation catalysis. Through a systematic examination of catalytic sites on nanoparticles, we identify several systems as top candidates with Pt-enriched surfaces, remarkable thermal stability, and superior catalytic activity for propane dehydrogenation. The insights gained garnered from this study are anticipated to provide a valuable framework for the optimal design of other bimetallic nanoparticles.

Keywords: bimetallic nanoparticles, platinum-group element, catalysis, surface segregation, first-principles calculations

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946 Molecular Study of P53- and Rb-Tumor Suppressor Genes in Human Papilloma Virus-Infected Breast Cancers

Authors: Shakir H. Mohammed Al-Alwany, Saad Hasan M. Ali, Ibrahim Mohammed S. Shnawa

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The study was aimed to define the percentage of detection of high-oncogenic risk types of HPV and their genotyping in archival tissue specimens that ranged from apparently healthy tissue to invasive breast cancer by using one of the recent versions of In Situ Hybridization(ISH) 0.2. To find out rational significance of such genotypes as well as over expressed products of mutants P53 and RB genes on the severity of underlying breast cancers. The DNA of HPV was detected in 46.5 % of tissues from breast cancers while HPV DNA in the tissues from benign breast tumours was detected in 12.5%. No HPV positive–ISH reaction was detected in healthy breast tissues of the control group. HPV DNA of genotypes (16, 18, 31 and 33) was detected in malignant group in frequency of 25.6%, 27.1%, 30.2% and 12.4%, respectively. Over expression of p53 was detected by IHC in 51.2% breast cancer cases and in 50% benign breast tumour group, while none of control group showed P53- over expression. Retinoblastoma protein was detected by IHC test in 49.7% of malignant breast tumours, 54.2% of benign breast tumours but no signal was reported in the tissues of control group. The significance prevalence of expression of mutated p53 & Rb genes as well as detection of high-oncogenic HPV genotypes in patients with breast cancer supports the hypothesis of an etiologic role for the virus in breast cancer development.

Keywords: human papilloma virus, P53, RB, breast cancer

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945 The Application of Insects in Forensic Investigations

Authors: Shirin Jalili, Hadi Shirzad, Samaneh Nabavi, Somayeh Khanjani

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Forensic entomology is the science of study and analysis of insects evidences to aid in criminal investigation. Being aware of the distribution, biology, ecology and behavior of insects, which are founded at crime scene can provide information about when, where and how the crime has been committed. It has many application in criminal investigations. Its main use is estimation of the minimum time after death in suspicious death. The close association between insects and corpses and the use of insects in criminal investigations is the subject of forensic entomology. Because insects attack to the decomposing corpse and spawning on it from the initial stages. Forensic scientists can estimate the postmortem index by studying the insects population and the developing larval stages.In addition, toxicological and molecular studies of these insects can reveal the cause of death or even the identity of a victim. It also be used to detect drugs and poisons, and determination of incident location. Gathering robust entomological evidences is made possible for experts by recent Techniques. They can provide vital information about death, corpse movement or burial, submersion interval, time of decapitation, identification of specific sites of trauma, post-mortem artefacts on the body, use of drugs, linking a suspect to the scene of a crime, sexual molestations and the identification of suspects.

Keywords: Forensic entomology, post mortem interval, insects, larvae

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944 Combination Rule for Homonuclear Dipole Dispersion Coefficients

Authors: Giorgio Visentin, Inna S. Kalinina, Alexei A. Buchachenko

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In the ambit of intermolecular interactions, a combination rule is defined as a relation linking a potential parameter for the interaction of two unlike species with the same parameters for interaction pairs of like species. Some of their most exemplificative applications cover the construction of molecular dynamics force fields and dispersion-corrected density functionals. Here, an extended combination rule is proposed, relating the dipole-dipole dispersion coefficients for the interaction of like target species to the same coefficients for the interaction of the target and a set of partner species. The rule can be devised in two different ways, either by uniform discretization of the Casimir-Polder integral on a Gauss-Legendre quadrature or by relating the dynamic polarizabilities of the target and the partner species. Both methods return the same system of linear equations, which requires the knowledge of the dispersion coefficients for interaction between the partner species to be solved. The test examples show a high accuracy for dispersion coefficients (better than 1% in the pristine test for the interaction of Yb atom with rare gases and alkaline-earth metal atoms). In contrast, the rule does not ensure correct monotonic behavior of the dynamic polarizability of the target species. Acknowledgment: The work is supported by Russian Science Foundation grant # 17-13-01466.

Keywords: combination rule, dipole-dipole dispersion coefficient, Casimir-Polder integral, Gauss-Legendre quadrature

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943 Oral Microflora and the Risk of Dental Caries in Portuguese Children

Authors: Sara Sousa, Veronique Gomes, Nélio Veiga, Maria José Correia

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Objectives: To assess the presence or absence of Streptococcus mutans, Streptococcus gordonii and Streptococcus salivarius in the oral biofilm of children in an elementary school of Viseu, Portugal, and verify the relationship between Streptococcus gordonii and Streptococcus salivarius and the absence of dental caries. Methods: A cross-sectional study was designed with a final sample of 40 children aged 6-11 years old. Oral examination was accomplished with the identification of their oral health status and oral biofilm collection. Analysis of biological samples by molecular techniques of DNA isolation and identification of three Streptococci bacteria by Polimerase Chain Reaction (PCR) was made. Results: We identified Streptococcus salivarius and Streptococcus gordoni only in the lower interincisal region. These species were also present mainly in the first permanent non-decayed molars. On the contrary, Streptococcus mutans was found mostly in decayed first permanent molars. Conclusion: This preliminary study establishes a possible association between the absence of dental caries and the presence of Streptococcus gordonii and Streptococcus salivarius. Since these two species are described as alkali producers, it is suggested that their presence somehow confers protection against caries. These results support new dental caries prevention strategies based on oral biofilm modulation by enrichment with alkalinogenic species.

Keywords: dental caries, oral biofilm, Streptococcus gordonii, Streptococcus salivarius

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942 LncRNA NEAT1 Promotes NSCLC Progression through Acting as a ceRNA of miR-377-3p

Authors: Chengcao Sun, Shujun Li, Cuili Yang, Yongyong Xi, Liang Wang, Feng Zhang, Dejia Li

Abstract:

Recently, the long non-coding RNA (lncRNA) NEAT1 has been identified as an oncogenic gene in multiple cancer types and elevated expression of NEAT1 was tightly linked to tumorigenesis and cancer progression. However, the molecular basis for this observation has not been characterized in progression of non-small cell lung cancer (NSCLC). In our studies, we identified NEAT1 was highly expressed in NSCLC patients and was a novel regulator of NSCLC progression. Patients whose tumors had high NEAT1 expression had a shorter overall survival than patients whose tumors had low NEAT1 expression. Further, NEAT1 significantly accelerates NSCLC cell growth and metastasis in vitro and tumor growth in vivo. Additionally, by using bioinformatics study and RNA pull down combined with luciferase reporter assays, we demonstrated that NEAT1 functioned as a competing endogenous RNA (ceRNA) for has-miR-377-3p, antagonized its functions and led to the de-repression of its endogenous targets E2F3, which was a core oncogene in promoting NSCLC progression. Taken together, these observations imply that the NEAT1 modulated the expression of E2F3 gene by acting as a competing endogenous RNA, which may build up the missing link between the regulatory miRNA network and NSCLC progression.

Keywords: long non-coding RNA NEAT1, hsa-miRNA-377-3p, E2F3, non-small cell lung cancer, tumorigenesis

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941 In-Vivo Association of Multivalent 11 Zinc Fingers Transcriptional Factors CTCF and Boris to YB-1 in Multiforme Glioma-RGBM Cell Line

Authors: Daruliza Kernain, Shaharum Shamsuddin, See Too Wei Cun

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CTCF is a unique, highly conserved and ubiquitously expressed 11 zinc finger (ZF) transcriptional factor with multiple target sites. It is able to bind to various target sequences to perform different regulatory roles including promoter activation or repression, creating hormone-responsive gene silencing element, and functional block of enhancer-promoter interactions. The binding of CTCF to the essential binding site is through the combination of different ZF domain. On the other hand, BORIS for brother of the regulator of imprinted sites, which expressed only in the testis and certain cancer cell line is homology to CTCF 11 ZF domains. Since both transcriptional factors share the same ZF domains hence there is a possibility for both to bind to the same target sequences. In this study, the interaction of these two proteins to multi-functional Y-box DNA/RNA-binding factor, YB-1 was determined. The protein-protein interaction between CTCF/YB-1 and BORIS/YB-1 were discovered by Co-immuno-precipitation (CO-IP) technique through reciprocal experiment from RGBM total cell lysate. The results showed that both CTCF and BORIS were able to interact with YB-1 in Glioma RGBM cell line. To the best of our knowledge, this is the first findings demonstrating the ability of BORIS and YB-1 to form a complex in vivo.

Keywords: immunoprecipitation, CTCF/BORIS/YB-1, transcription factor, molecular medicine

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940 Peridynamic Modeling of an Isotropic Plate under Tensile and Flexural Loading

Authors: Eda Gök

Abstract:

Peridynamics is a new modeling concept of non-local interactions for solid structures. The formulations of Peridynamic (PD) theory are based on integral equations rather than differential equations. Through, undefined equations of associated problems are avoided. PD theory might be defined as continuum version of molecular dynamics. The medium is usually modeled with mass particles bonded together. Particles interact with each other directly across finite distances through central forces named as bonds. The main assumption of this theory is that the body is composed of material points which interact with other material points within a finite distance. Although, PD theory developed for discontinuities, it gives good results for structures which have no discontinuities. In this paper, displacement control of the isotropic plate under the effect of tensile and bending loading has been investigated by means of PD theory. A MATLAB code is generated to create PD bonds and corresponding surface correction factors. Using generated MATLAB code the geometry of the specimen is generated, and the code is implemented in Finite Element Software. The results obtained from non-local continuum theory are compared with the Finite Element Analysis results and analytical solution. The results show good agreement.

Keywords: non-local continuum mechanics, peridynamic theory, solid structures, tensile loading, flexural loading

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939 Optimization of Adsorptive Removal of Common Used Pesticides Water Wastewater Using Golden Activated Charcoal

Authors: Saad Mohamed Elsaid, Nabil Anwar, Mahmoud Rushdi

Abstract:

One of the reasons for the intensive use of pesticides is to protect agricultural crops and orchards from pests or agricultural worms. The period of time that pesticides stay inside the soil is estimated at about (2) to (12) weeks. Perhaps the most important reason that led to groundwater pollution is the easy leakage of these harmful pesticides from the soil into the aquifers. This research aims to find the best ways to use traded activated charcoal with gold nitrate solution; for removing the deadly pesticides from the aqueous solution by adsorption phenomenon. The most used pesticides in Egypt were selected, such as Malathion, Methomyl Abamectin and, Thiamethoxam. Activated charcoal doped with gold ions was prepared by applying chemical and thermal treatments to activated charcoal using gold nitrate solution. Adsorption of studied pesticide onto activated carbon /Au was mainly by chemical adsorption, forming a complex with the gold metal immobilized on activated carbon surfaces. In addition, the gold atom was considered as a catalyst to cracking the pesticide molecule. Gold activated charcoal is a low cost material due to the use of very low concentrations of gold nitrate solution. its notice the great ability of activated charcoal in removing selected pesticides due to the presence of the positive charge of the gold ion, in addition to other active groups such as functional oxygen and lignin cellulose. The presence of pores of different sizes on the surface of activated charcoal is the driving force for the good adsorption efficiency for the removal of the pesticides under study The surface area of the prepared char as well as the active groups, were determined using infrared spectroscopy and scanning electron microscopy. Some factors affecting the ability of activated charcoal were applied in order to reach the highest adsorption capacity of activated charcoal, such as the weight of the charcoal, the concentration of the pesticide solution, the time of the experiment, and the pH. Experiments showed that the maximum limit revealed by the batch adsorption study for the adsorption of selected insecticides was in contact time (80) minutes at pH (7.70). These promising results were confirmed, and by establishing the practical application of the developed system, the effect of various operating factors with equilibrium, kinetic and thermodynamic studies is evident, using the Langmuir application on the effectiveness of the absorbent material with absorption capacities higher than most other adsorbents.

Keywords: waste water, pesticides pollution, adsorption, activated carbon

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938 Effect of Acute Dose of Mobile Phone Radiation on Life Cycle ‎of the Mosquito, Culex univittatus

Authors: Fatma H. Galal, Alaaeddeen M. Seufi

Abstract:

Due to the increasing usage of mobile phone, experiments were designed to investigate ‎the effect of acute dose exposure on the mosquito life cycle. 50 tubes (5 ml size) ‎containing 3 ml water and a first instar larva of the mosquito, Culex univittatus were put ‎between two mobile cell phones switched on talking mode for 4 continuous hours. A ‎control group of tubes (unexposed to radiation) were used. Larval and pupal durations ‎were calculated. Furthermore, adult emergence and sex ratio were observed for both ‎treated and control larvae. Results indicated that the employed dose of radiation reduced ‎total larval duration to about half the value of control. 1st, 2nd, 3rd and 4th larval ‎durations were reduced significantly by mobile radiation when compared to controls. ‎Meanwhile pupal duration was elongated significantly by mobile radiation when ‎compared to control. Sex ratio was significantly shifted in favor of females in the case of ‎radiated mosquitoes. Successful adult emergence was decreased significantly in the case ‎of radiated insects when compared to controls. Molecular studies to investigate the ‎effects of mobile radiation on insects and other model organisms are going on.‎

Keywords: mosquito, mobilr radiation, larval and pupal durations, sex ratio

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937 Fouling of Regenerated Ultrafiltration Membrane in Treatment of Oily Wastewater of Palm Oil Refinery

Authors: K. F. Md Yunos, N. S. Pajar, N. S. Azmi

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Oily wastewater in Malaysian refinery has become a big issue of water and environment pollution to be solved urgently. The results of an experimental study on separation of oily wastewaters are presented. The characteristic of filtration behavior of commercial polymer ultrafiltration (UF) membranes was evaluated in the treatment of oily wastewater from palm oil refinery. The performance of different molecular weight cut off 5kDa and 10kDa regenerated cellulose membrane were evaluated and compared and the fouling behavior were analyzed by scanning electron microscopy (SEM). The effect of pressure (0.5, 1.0, 1.5, 2.0, 2.5 bar) and sample concentration (100%, 75%, 50%, 25%) on fouling of 5kDa and 10kDa membrane were evaluated. The characteristic of the sample solutions were analyzed for turbidity, total dissolved solid (TDS), total suspended solid (TSS), BOD, and COD. The results showed that the best fit to experimental data corresponds to the cake layer formation followed by the intermediate blocking for the experimental conditions tested. A more detailed analysis of the fouling mechanisms was studied by dividing the filtration curves into different regions corresponding to the different fouling mechanisms. Intermediate blocking and cake layer formation or combinations of them were found to occur during the UF experiments depending on the operating conditions.

Keywords: fouling, oily wastewater, regenerated cellulose, ultrafiltration

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936 CO2 Capture in Porous Silica Assisted by Lithium

Authors: Lucero Gonzalez, Salvador Alfaro

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Carbon dioxide (CO2) and methane (CH4) are considered as the compounds with higher abundance among the greenhouse gases (CO2, NOx, SOx, CxHx, etc.), due to its higher concentration, this two gases have a greater impact in the environment pollution and provokes global warming. So, recovery, disposal and subsequent reuse, are of great interest, especially from the ecological and health perspective. By one hand, porous inorganic materials are good candidates to capture gases, because these type of materials are higher stability from the point view of thermal, chemical and mechanical under adsorption gas processes. By another hand, during the design and the synthetic preparation of the porous materials is possible add other intrinsic properties (physicochemical and structural) by adding chemical compounds as dopants or using structured directed agents or surfactants to improve the porous structure, the above features allow to have alternative materials for separation, capture and storage of greenhouse gases. In this work, ordered mesoporous materials base silica were prepared using Surfynol as surfactant. The surfactant micelles are commonly used as self-assembly templates for the development of new structure porous silica’s, adding a variety of textures and structures. By another hand, the Surfynol is a commercial surfactant, is non-ionic, for that is necessary determine its critical micelles concentration (cmc) by the pyrene I1/I3 ratio method, before to prepare silica particles. One time known the CMC, a precursor gel was prepared via sol-gel process at room temperature using TEOS as silica precursor, NH4OH as catalyst, Surfynol as template and H2O as solvent. Then, the gel precursor was treatment hydrothermally in a Teflon-lined stainless steel autoclave with a volume of 100 mL and kept at 100 ºC for 24 h under static conditions in a convection oven. After that, the porous silica particles obtained were impregnated with lithium to improve the CO2 adsorption capacity. Then the silica particles were characterized physicochemical, morphology and structurally, by XRD, FTIR, BET and SEM techniques. The thermal stability and the CO2 adsorption capacity was evaluated by thermogravimetric analysis (TGA). According the results, we found that the Surfynol is a good candidate to prepare silica particles with an ordered structure. Also the TGA analysis shown that the particles has a good thermal stability in the range of 250 °C and 800 °C. The best materials had, the capacity to adsorbing 70 and 90 mg per gram of silica particles and its CO2 adsorption capacity depends on the way to thermal pretreatment of the porous silica before of the adsorption experiments and of the concentration of surfactant used during the synthesis of silica particles. Acknowledgments: This work was supported by SIP-IPN through project SIP-20161862.

Keywords: CO2 adsorption, lithium as dopant, porous silica, surfynol as surfactant, thermogravimetric analysis

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935 Insulin Secretory Actions of Spirulina platensis in Perfused Rat Pancreas, Isolated Mouse Islets, and Clonal Pancreatic Β-Cells

Authors: Jma Hannan, Prawej Ansari, Yasser H. A. Abdel-Wahab, Peter R. Flatt

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Spirulina platensis (SP, Blue-green algae) have been accepted as a supplement for the treatment of pre and post-diabetes. The present study investigated the effects of butanol fraction from ethanol extract of S. platensis on insulin release from BRIN BD11 cells, isolated mouse islets, and perfused rat pancreas, as well as glucose homeostasis in type 2 diabetic rats and their molecular pathways. In a dose-dependent manner, S. platensis increased insulin release from mouse islets and pancreatic β-cells. The extract also elevated insulin release in perfused rat pancreas. Glucose, isobutylmethylxanthine, tolbutamide, and a depolarizing concentration of KCl significantly potentiated insulin release from BRIN BD11 cells. The effect of diazoxide and verapamil, as well as the absence of extracellular Ca2+ showed a reduction in insulin secretion. When administered orally together with glucose (2.5g/kg bw), S. platensis extract improved fasting and postprandial blood glucose in type 2 diabetes. These data suggest that the anti-diabetic activity of S. platensis is partly mediated by insulin secretion via the KATP channel-dependent pathway/the intracellular cAMP pathway.

Keywords: Insulin, glucose, S. platensis, type 2 diabetes, medicinal plants

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934 Thermal Diffusion of Photovoltaic Organic Semiconductors Determined by Scanning Photothermal Deflection Technique

Authors: K.L. Chiu, Johnny K. W. Ho, M. H. Chan, S. H. Cheung, K. H. Chan, S.K. So

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Thermal diffusivity is an important quantity in heat conduction. It measures the rate of heat transfer from the hot side to the cold side of a material. In solid-state materials, thermal diffusivity reveals information related to morphologies and solid quality, as thermal diffusivity can be affected by microstructures. However, thermal diffusivity studies on organic semiconductors are very limited. In this study, scanning photothermal deflection (SPD) technique is used to study the thermal diffusivities of different classes of semiconducting polymers. The reliability of the technique was confirmed by crossing-checking our SPD derived experimental values of different reference materials with their known diffusivities from the literature. To show that thermal diffusivity determination is a potential tool for revealing microscopic properties of organic photovoltaic semiconductors, SPD measurements were applied to various organic semiconducting films with different crystallinities. It is observed that organic photovoltaic semiconductors possess low thermal diffusivity, with values in the range of 0.3mm²/s to 1mm²/s. It is also discovered that polymeric photovoltaic semiconductors with greater molecular planarity, stronger stacking and higher crystallinity would possess greater thermal diffusivities. Correlations between thermal, charge transport properties will be discussed.

Keywords: polymer crystallinity, photovoltaic organic semiconductors, photothermal deflection technique, thermal diffusion

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933 Exploring the Concept of Fashion Waste: Hanging by a Thread

Authors: Timothy Adam Boleratzky

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The goal of this transformative endeavour lies in the repurposing of textile scraps, heralding a renaissance in the creation of wearable art. Through a judicious fusion of Life Cycle Assessment (LCA) methodologies and cutting-edge techniques, this research embarks upon a voyage of exploration, unraveling the intricate tapestry of environmental implications woven into the fabric of textile waste. Delving deep into the annals of empirical evidence and scholarly discourse, the study not only elucidates the urgent imperative for waste reduction strategies but also unveils the transformative potential inherent in embracing circular economy principles within the hallowed halls of fashion. As the research unfurls its sails, guided by the compass of sustainability, it traverses uncharted territories, charting a course toward a more enlightened and responsible fashion ecosystem. The canvas upon which this journey unfolds is richly adorned with insights gleaned from the crucible of experimentation, laying bare the myriad pathways toward waste minimisation and resource optimisation. From the adoption of recycling strategies to the cultivation of eco-friendly production techniques, the research endeavours to sculpt a blueprint for a more sustainable future, one stitch at a time. In this unfolding narrative, the role of wearable art emerges as a potent catalyst for change, transcending the boundaries of conventional fashion to embrace a more holistic ethos of sustainability. Through the alchemy of creativity and craftsmanship, discarded textile scraps are imbued with new life, morphing into exquisite creations that serve as both a testament to human ingenuity and a rallying cry for environmental preservation. Each thread, each stitch, becomes a silent harbinger of change, weaving together a tapestry of hope in a world besieged by ecological uncertainty. As the research journey culminates, its echoes resonate far beyond the confines of academia, reverberating through the corridors of industry and beyond. In its wake, it leaves a legacy of empowerment and enlightenment, inspiring a generation of designers, entrepreneurs, and consumers to embrace a more sustainable vision of fashion. For in the intricate interplay of threads and textiles lies the promise of a brighter, more resilient future, where beauty coexists harmoniously with responsibility and where fashion becomes not merely an expression of style but a celebration of sustainability.

Keywords: fabric-manipulation, sustainability, textiles, waste, wearable-art

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932 Bibliometric Analysis of Risk Assessment of Inland Maritime Accidents in Bangladesh

Authors: Armana Huq, Wahidur Rahman, Sanwar Kader

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Inland waterways in Bangladesh play an important role in providing comfortable and low-cost transportation. However, a maritime accident takes away many lives and creates unwanted hazards every year. This article deals with a comprehensive review of inland waterway accidents in Bangladesh. Additionally, it includes a comparative study between international and local inland research studies based on maritime accidents. Articles from inland waterway areas are analyzed in-depth to make a comprehensive overview of the nature of the academic work, accident and risk management process and different statistical analyses. It is found that empirical analysis based on the available statistical data dominates the research domain. For this study, major maritime accident-related works in the last four decades in Bangladesh (1981-2020) are being analyzed for preparing a bibliometric analysis. A study of maritime accidents of passenger's vessels during (1995-2005) indicates that the predominant causes of accidents in the inland waterways of Bangladesh are collision and adverse weather (77%), out of which collision due to human error alone stands (56%) of all accidents. Another study refers that the major causes of waterway accidents are the collision (60.3%) during 2005-2015. About 92% of this collision occurs due to direct contact with another vessel during this period. Rest 8% of the collision occurs by contact with permanent obstruction on waterway roots. The overall analysis of another study from the last 25 years (1995-2019) shows that one of the main types of accidents is collisions, with about 50.3% of accidents being caused by collisions. The other accident types are cyclone or storm (17%), overload (11.3%), physical failure (10.3%), excessive waves (5.1%), and others (6%). Very few notable works are available in testing or comparing the methods, proposing new methods for risk management, modeling, uncertainty treatment. The purpose of this paper is to provide an overview of the evolution of marine accident-related research domain regarding inland waterway of Bangladesh and attempts to introduce new ideas and methods to abridge the gap between international and national inland maritime-related work domain which can be a catalyst for a safer and sustainable water transportation system in Bangladesh. Another fundamental objective of this paper is to navigate various national maritime authorities and international organizations to implement risk management processes for shipping accident prevention in waterway areas.

Keywords: inland waterways, safety, bibliometric analysis, risk management, accidents

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931 Functional Characterization of Transcriptional Regulator WhiB Proteins of Mycobacterium Tuberculosis

Authors: Sonam Kumari

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Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, possesses a remarkable feature of entering into and emerging from a persistent state. The mechanism by which Mtb switches from the dormant state to the replicative form is still poorly characterized. Proteome studies have given us an insight into the role of certain proteins in giving stupendous virulence to Mtb, but numerous dotsremain unconnected and unaccounted. The WhiB family of proteins is one such protein that is associated with developmental processes in actinomycetes.Mtb has seven such proteins (WhiB1 to WhiB7).WhiB proteins are transcriptional regulators; their conserved C-terminal HTH motif is involved in DNA binding. They regulate various essential genes of Mtbby binding to their promoter DNA. Biophysical Analysis of the effect of DNA binding on WhiB proteins has not yet been appropriately characterized. Interaction with DNA induces conformational changes in the WhiB proteins, confirmed by steady-state fluorescence and circular dichroism spectroscopy. ITC has deduced thermodynamic parameters and the binding affinity of the interaction. Since these transcription factors are highly unstable in vitro, their stability and solubility were enhanced by the co-expression of molecular chaperones. The present study findings help determine the conditions under which the WhiB proteins interact with their interacting partner and the factors that influence their binding affinity. This is crucial in understanding their role in regulating gene expression in Mtbandin targeting WhiB proteins as a drug target to cure TB.

Keywords: tuberculosis, WhiB proteins, mycobacterium tuberculosis, nucleic acid binding

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930 Depth of Field: Photographs, Narrative and Reflective Learning Resource for Health Professions Educators

Authors: Gabrielle Brand, Christopher Etherton-Beer

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The learning landscape of higher education environment is changing, with an increased focus over the past decade on how educators might begin to cultivate reflective skills in health professions students. In addition, changing professional requirements demand that health professionals are adequately prepared to practice in today’s complex Australian health care systems, including responding to changing demographics of population ageing. To counteract a widespread perception of health professions students’ disinterest in caring for older persons, the authors will report on an exploratory, mixed method research study that used photographs, narrative and small group work to enhance medical and nursing students’ reflective learning experience. An innovative photo-elicitation technique and reflective questioning prompts were used to increase engagement, and challenge students to consider new perspectives (around ageing) by constructing shared storylines in small groups. The qualitative themes revealed how photographs, narratives and small group work created learning spaces for reflection whereby students could safely explore their own personal and professional values, beliefs and perspectives around ageing. By providing the space for reflection, the students reported how they found connection and meaning in their own learning through a process of self-exploration that often challenged their assumptions of both older people and themselves as future health professionals. By integrating cognitive and affective elements into the learning process, this research demonstrates the importance of embedding visual methodologies that enhance reflection and transformative learning. The findings highlight the importance of integrating the arts into predominantly empirically driven health professional curricula and can be used as a catalyst for individual and/or collective reflection which can potentially enhance empathy, insight and understanding of the lived experiences of older patients. Based on these findings, the authors have developed ‘Depth of Field: Exploring Ageing’ an innovative, interprofessional, digital reflective learning resource that uses Prezi Inc. software (storytelling tool that presents ideas on a virtual canvas) to enhance students’ reflective capacity in the higher education environment.

Keywords: narrative, photo-elicitation, reflective learning, qualitative research

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929 Sema4D/Plexin-B1 Signaling Regulates Osteo/Odontogenic Differentiation of Dental Pulp Stem Cells

Authors: Ting Zou, Chengfei Zhang

Abstract:

Objectives: The purpose of this study was to investigate the role of Semaphorin 4D (Sema4D)/Plexin-B1 signaling on osteo/odontogenic differentiation of human dental pulp stem cells (DPSCs) and uncover its molecular mechanism. Methods: DPSCs were cultured in osteo/odontogenic medium. After treatment with Sema4D (10μg/mL), osteo/odontogenic differentiation and mineralization was evaluated by measuring alkaline phosphatase (ALP) activity and alizarin red S staining respectively. The expression of osteo/odontogenic genes (ALP, Col1A1, BSP, and Runx2) was determined by real-time polymerase chain reaction. p-Plexin-B1, Plexin-B1, Col1A1, RhoA, and ErbB2 were analyzed by western. Results: ALP activity and mineralization formation of DPSCs were significantly decreased after treatment with Sema4D (P<0.05). Sema4D significantly down-regulated osteo/odontogenic-related genes expression (ALP, Col1A1, BSP, and Runx2). p-Plexin-B1, Plexin-B1 and RhoA protein expression levels increased after stimulated with Sema4D, while the expression of Col1A1 decreased. Pretreatment with Plexin-B1 antibody blocked Sema4D induced p-Plexin-B1 expression. Conclusion: Sema4D suppressed osteo/odontogenic differentiation of DPSCs via RhoA-mediated pathways.

Keywords: Sema4D/Plexin-B1, dental pulp stem cells, osteo/odontogenic differentiation, alkaline phosphatase (ALP)

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928 H2 Permeation Properties of a Catalytic Membrane Reactor in Methane Steam Reforming Reaction

Authors: M. Amanipour, J. Towfighi, E. Ganji Babakhani, M. Heidari

Abstract:

Cylindrical alumina microfiltration membrane (GMITM Corporation, inside diameter=9 mm, outside diameter=13 mm, length= 50 mm) with an average pore size of 0.5 micrometer and porosity of about 0.35 was used as the support for membrane reactor. This support was soaked in boehmite sols, and the mean particle size was adjusted in the range of 50 to 500 nm by carefully controlling hydrolysis time, and calcined at 650 °C for two hours. This process was repeated with different boehmite solutions in order to achieve an intermediate layer with an average pore size of about 50 nm. The resulting substrate was then coated with a thin and dense layer of silica by counter current chemical vapour deposition (CVD) method. A boehmite sol with 10 wt.% of nickel which was prepared by a standard procedure was used to make the catalytic layer. BET, SEM, and XRD analysis were used to characterize this layer. The catalytic membrane reactor was placed in an experimental setup to evaluate the permeation and hydrogen separation performance for a steam reforming reaction. The setup consisted of a tubular module in which the membrane was fixed, and the reforming reaction occurred at the inner side of the membrane. Methane stream, diluted with nitrogen, and deionized water with a steam to carbon (S/C) ratio of 3.0 entered the reactor after the reactor was heated up to 500 °C with a specified rate of 2 °C/ min and the catalytic layer was reduced at presence of hydrogen for 2.5 hours. Nitrogen flow was used as sweep gas through the outer side of the reactor. Any liquid produced was trapped and separated at reactor exit by a cold trap, and the produced gases were analyzed by an on-line gas chromatograph (Agilent 7890A) to measure total CH4 conversion and H2 permeation. BET analysis indicated uniform size distribution for catalyst with average pore size of 280 nm and average surface area of 275 m2.g-1. Single-component permeation tests were carried out for hydrogen, methane, and carbon dioxide at temperature range of 500-800 °C, and the results showed almost the same permeance and hydrogen selectivity values for hydrogen as the composite membrane without catalytic layer. Performance of the catalytic membrane was evaluated by applying membranes as a membrane reactor for methane steam reforming reaction at gas hourly space velocity (GHSV) of 10,000 h−1 and 2 bar. CH4 conversion increased from 50% to 85% with increasing reaction temperature from 600 °C to 750 °C, which is sufficiently above equilibrium curve at reaction conditions, but slightly lower than membrane reactor with packed nickel catalytic bed because of its higher surface area compared to the catalytic layer.

Keywords: catalytic membrane, hydrogen, methane steam reforming, permeance

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927 Microstructure Analysis of Biopolymer Mixture (Chia-Gelatin) by Laser Confocal Microscopy

Authors: Emmanuel Flores Huicochea, Guadalupe Borja Mendiola, Jacqueline Flores Lopez, Rodolfo Rendon Villalobos

Abstract:

The usual procedure to investigate the properties of biodegradable films has been to prepare the film, measure the mechanical or transport properties and then decide whether the mixture has better properties than the individual components, instead of investigating whether the mixture has biopolymer-biopolymer interaction, then prepare the film and finally measure the properties of the film. The work investigates the presence of interaction biopolymer-biopolymer in a mixture of chia biopolymer and gelatin using Laser Confocal Microscopy (LCM). Previously, the chia biopolymer was obtained from chia seed. CML analysis of mixtures of chia biopolymer-gelatin without Na⁺ ions exhibited aggregates of different size, in the range of 100-400 μm, of defined color, for the two colors, but no mixing of color was observed. The increased of gelatin in the mixture decreases the size and number of aggregates. The tridimensional microstructure reveled that there are two layers of biopolymers, chia and gelatin well defined. The mixture chia biopolymer-gelatin with 10 mM Na⁺ and with a ratio 75:25 (chia-gelatin) showed lower aggregated size than others mixture with and without ions. This result could be explained because the chia biopolymer is a polyelectrolyte and the added sodium ions reduce the molecular rigidity by neutralizing the negative charges that the chia biopolymer possesses and therefore a better biopolymer-biopolymer interaction is allowed between the biopolymer of chia and gelatin.

Keywords: biopolymer-biopolymer interaction, confocal laser microscopy, CLM, microstructure, mixture chia-gelatin

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926 A Green Process for Drop-In Liquid Fuels from Carbon Dioxide, Water, and Solar Energy

Authors: Jian Yu

Abstract:

Carbo dioxide (CO2) from fossil fuel combustion is a prime green-house gas emission. It can be mitigated by microalgae through conventional photosynthesis. The algal oil is a feedstock of biodiesel, a carbon neutral liquid fuel for transportation. The conventional CO2 fixation, however, is quite slow and affected by the intermittent solar irradiation. It is also a technical challenge to reform the bio-oil into a drop-in liquid fuel that can be directly used in the modern combustion engines with expected performance. Here, an artificial photosynthesis system is presented to produce a biopolyester and liquid fuels from CO2, water, and solar power. In this green process, solar energy is captured using photovoltaic modules and converted into hydrogen as a stable energy source via water electrolysis. The solar hydrogen is then used to fix CO2 by Cupriavidus necator, a hydrogen-oxidizing bacterium. Under the autotrophic conditions, CO2 was reduced to glyceraldehyde-3-phosphate (G3P) that is further utilized for cell growth and biosynthesis of polyhydroxybutyrate (PHB). The maximum cell growth rate reached 10.1 g L-1 day-1, about 25 times faster than that of a typical bio-oil-producing microalga (Neochloris Oleoabundans) under stable indoor conditions. With nitrogen nutrient limitation, a large portion of the reduced carbon is stored in PHB (C4H6O2)n, accounting for 50-60% of dry cell mass. PHB is a biodegradable thermoplastic that can find a variety of environmentally friendly applications. It is also a platform material from which small chemicals can be derived. At a high temperature (240 - 290 oC), the biopolyester is degraded into crotonic acid (C4H6O2). On a solid phosphoric acid catalyst, PHB is deoxygenated via decarboxylation into a hydrocarbon oil (C6-C18) at 240 oC or so. Aromatics and alkenes are the major compounds, depending on the reaction conditions. A gasoline-grade liquid fuel (77 wt% oil) and a biodiesel-grade fuel (23 wt% oil) were obtained from the hydrocarbon oil via distillation. The formation routes of hydrocarbon oil from crotonic acid, the major PHB degradation intermediate, are revealed and discussed. This work shows a novel green process from which biodegradable plastics and high-grade liquid fuels can be directly produced from carbon dioxide, water and solar power. The productivity of the green polyester (5.3 g L-1 d-1) is much higher than that of microalgal oil (0.13 g L-1 d-1). Other technical merits of the new green process may include continuous operation under intermittent solar irradiation and convenient scale up in outdoor.

Keywords: bioplastics, carbon dioxide fixation, drop-in liquid fuels, green process

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925 Energy Deposited by Secondary Electrons Generated by Swift Proton Beams through Polymethylmethacrylate

Authors: Maurizio Dapor, Isabel Abril, Pablo de Vera, Rafael Garcia-Molina

Abstract:

The ionization yield of ion tracks in polymers and bio-molecular systems reaches a maximum, known as the Bragg peak, close to the end of the ion trajectories. Along the path of the ions through the materials, many electrons are generated, which produce a cascade of further ionizations and, consequently, a shower of secondary electrons. Among these, very low energy secondary electrons can produce damage in the biomolecules by dissociative electron attachment. This work deals with the calculation of the energy distribution of electrons produced by protons in a sample of polymethylmethacrylate (PMMA), a material that is used as a phantom for living tissues in hadron therapy. PMMA is also of relevance for microelectronics in CMOS technologies and as a photoresist mask in electron beam lithography. We present a Monte Carlo code that, starting from a realistic description of the energy distribution of the electrons ejected by protons moving through PMMA, simulates the entire cascade of generated secondary electrons. By following in detail the motion of all these electrons, we find the radial distribution of the energy that they deposit in PMMA for several initial proton energies characteristic of the Bragg peak.

Keywords: Monte Carlo method, secondary electrons, energetic ions, ion-beam cancer therapy, ionization cross section, polymethylmethacrylate, proton beams, secondary electrons, radial energy distribution

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924 The Development of a Miniaturized Raman Instrument Optimized for the Detection of Biosignatures on Europa

Authors: Aria Vitkova, Hanna Sykulska-Lawrence

Abstract:

In recent years, Europa has been one of the major focus points in astrobiology due to its high potential of harbouring life in the vast ocean underneath its icy crust. However, the detection of life on Europa faces many challenges due to the harsh environmental conditions and mission constraints. Raman spectroscopy is a highly capable and versatile in-situ characterisation technique that does not require any sample preparation. It has only been used on Earth to date; however, recent advances in optical and laser technology have also allowed it to be considered for extraterrestrial exploration. So far, most efforts have been focused on the exploration of Mars, the most imminent planetary target. However, as an emerging technology with high miniaturization potential, Raman spectroscopy also represents a promising tool for the exploration of Europa. In this study, the capabilities of Raman technology in terms of life detection on Europa are explored and assessed. Spectra of biosignatures identified as high priority molecular targets for life detection on Europa were acquired at various excitation wavelengths and conditions analogous to Europa. The effects of extremely low temperatures and low concentrations in water ice were explored and evaluated in terms of the effectiveness of various configurations of Raman instruments. Based on the findings, a design of a miniaturized Raman instrument optimized for in-situ detection of life on Europa is proposed.

Keywords: astrobiology, biosignatures, Europa, life detection, Raman Spectroscopy

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923 Valorization of Mineralogical Byproduct TiO₂ Using Photocatalytic Degradation of Organo-Sulfur Industrial Effluent

Authors: Harish Kuruva, Vedasri Bai Khavala, Tiju Thomas, K. Murugan, B. S. Murty

Abstract:

Industries are growing day to day to increase the economy of the country. The biggest problem with industries is wastewater treatment. Releasing these wastewater directly into the river is more harmful to human life and a threat to aquatic life. These industrial effluents contain many dissolved solids, organic/inorganic compounds, salts, toxic metals, etc. Phenols, pesticides, dioxins, herbicides, pharmaceuticals, and textile dyes were the types of industrial effluents and more challenging to degrade eco-friendly. So many advanced techniques like electrochemical, oxidation process, and valorization have been applied for industrial wastewater treatment, but these are not cost-effective. Industrial effluent degradation is complicated compared to commercially available pollutants (dyes) like methylene blue, methylene orange, rhodamine B, etc. TiO₂ is one of the widely used photocatalysts which can degrade organic compounds using solar light and moisture available in the environment (organic compounds converted to CO₂ and H₂O). TiO₂ is widely studied in photocatalysis because of its low cost, non-toxic, high availability, and chemically and physically stable in the atmosphere. This study mainly focused on valorizing the mineralogical product TiO₂ (IREL, India). This mineralogical graded TiO₂ was characterized and compared with its structural and photocatalytic properties (industrial effluent degradation) with the commercially available Degussa P-25 TiO₂. It was testified that this mineralogical TiO₂ has the best photocatalytic properties (particle shape - spherical, size - 30±5 nm, surface area - 98.19 m²/g, bandgap - 3.2 eV, phase - 95% anatase, and 5% rutile). The industrial effluent was characterized by TDS (total dissolved solids), ICP-OES (inductively coupled plasma – optical emission spectroscopy), CHNS (Carbon, Hydrogen, Nitrogen, and sulfur) analyzer, and FT-IR (fourier-transform infrared spectroscopy). It was observed that it contains high sulfur (S=11.37±0.15%), organic compounds (C=4±0.1%, H=70.25±0.1%, N=10±0.1%), heavy metals, and other dissolved solids (60 g/L). However, the organo-sulfur industrial effluent was degraded by photocatalysis with the industrial mineralogical product TiO₂. In this study, the industrial effluent pH value (2.5 to 10), catalyst concentration (50 to 150 mg) were varied, and effluent concentration (0.5 Abs) and light exposure time (2 h) were maintained constant. The best degradation is about 80% of industrial effluent was achieved at pH 5 with a concentration of 150 mg - TiO₂. The FT-IR results and CHNS analyzer confirmed that the sulfur and organic compounds were degraded.

Keywords: wastewater treatment, industrial mineralogical product TiO₂, photocatalysis, organo-sulfur industrial effluent

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922 Genetic Parameters as Indicators of Sustainability and Diversity of Schinus terebinthifolius Populations in the Riparian Area of the São Francisco River

Authors: Renata Silva-Mann, Sheila Valéria Álvares Carvalho, Robério Anastácio Ferreira, Laura Jane Gomes

Abstract:

There is growing interest in defining indicators of sustainability, which are important for monitoring the conservation of native forests, particularly in areas of permanent protection. These indicators are references for assessing the state of the forest and the status of the depredated area and its ability to maintain species populations. The aim of the present study was to select genetic parameters as indicators of sustainability for Schinus terebinthifolius Raddi. Fragments located in riparian areas between the Sergipe and Alagoas States in Brazil. This species has been exploited for traditional communities, which represent 20% of the incoming. This study was carried out using the indicators suggested by the Organization for Economic Cooperation and Development, which were identified as Driving-Pressure-State-Impact-Response (DPSIR) factors. The genetic parameters were obtained in five populations located on the shores and islands of the São Francisco River, one of the most important rivers in Brazil. The framework for Schinus conservation suggests seventeen indicators of sustainability. In accordance with genetic parameters, the populations are isolated, and these genetic parameters can be used to monitor the sustainability of those populations in riparian area with the aim of defining strategies for forest restoration.

Keywords: alleles, molecular markers, genetic diversity, biodiversity

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921 A Small-Molecular Inhibitor of Influenza Virus via Disrupting the PA and PB1 Interaction of the Viral Polymerase

Authors: Shuofeng Yuan, Bojian Zheng

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Assembly of the heterotrimeric polymerase complex of influenza virus from the individual subunits PB1, PA, and PB2 is a prerequisite for viral replication, in which the interaction between the N-terminal of PB1 (PB1N) and the C terminal of PA (PAC) may be a desired target for antiviral development. In this study, we first compared the feasibility of high throughput screening by enzyme-linked immunosorbent assay (ELISA) and fluorescence polarization (FP) assay. Among the two, ELISA was demonstrated to own broader dynamic range so that it was used for screening inhibitors, which blocked PA and PB1 interaction. Several binding inhibitors of PAC-PB1N were identified and subsequently tested for the antiviral efficacy. Apparently, 3-(2-chlorophenyl)-6-ethyl-7-methyl[1,2,4]triazolo[4,3-a]pyrimidin-5-ol, designated ANA-1, was found to be a strong inhibitor of PAC-PB1N interaction and act as a potent antiviral agent against the infections of multiple subtypes of influenza A virus, including H1N1, H3N2, H5N1, H7N7, H7N9 and H9N2 subtypes, in cell cultures. Intranasal administration of ANA-1 protected mice from lethal challenge and reduced lung viral loads in H1N1 virus infected BALB/c mice. Docking analyses predicted that ANA-1 bound to an allosteric site of PAC, which would cause conformational changes thereby disrupting the PAC-PB1N interaction. Overall, our study has identified a novel compound with potential to be developed as an anti-influenza drug.

Keywords: influenza, antiviral, viral polymerase, compounds

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920 Optical Characterization of Anisotropic Thiophene-Phenylene Co-Oligomer Micro Crystals by Spectroscopic Imaging Ellipsometry

Authors: Christian Röling, Elena Y. Poimanova, Vladimir V. Bruevich

Abstract:

Here we demonstrate a non-destructive optical technique to localize and characterize single crystals of semiconductive organic materials – Spectroscopic Imaging Ellipsometry. With a combination of microscopy and ellipsometry, it is possible to characterize even micro-sized thin film crystals on plane surface regarding anisotropy, optical properties, crystalline domains and thickness. The semiconducting thiophene-phenylene co-oligomer 1,4-bis(5'-hexyl-[2,2'-bithiophen]-5-yl)benzene (dHex-TTPTT) crystals were grown by solvent based self-assembly technique on silicon substrate with 300 nm thermally silicon dioxide. The ellipsometric measurements were performed with an Ep4-SE (Accurion). In an ellipsometric high-contrast image of the complete sample, we have localized high-quality single crystals. After demonstrating the uniaxial anisotropy of the crystal by using Müller-Matrix imaging ellipsometry, we determined the optical axes by rotating the sample and performed spectroscopic measurements (λ = 400-700 nm) in 5 nm intervals. The optical properties were described by using a Lorentz term in the Ep4-Model. After determining the dispersion of the crystals, we converted a recorded Delta and Psi-map into a 2D thickness image. Based on a quantitative analysis of the resulting thickness map, we have calculated the height of a molecular layer (3.49 nm).

Keywords: anisotropy, ellipsometry, SCFET, thin film

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