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Evaluation of extraction protocols for anti-diabetic phytochemical substances from medicinal plants

World Journal of diabetes 2016年第20期7卷 605-614页

作者： Stanley Irobekhian Reuben Okoduwa Ismaila A Umar dorcas B james Hajara M Inuwa james d habila directorate of Research and development Nigerian Institute of Leather and Science Technology department of Biochemistry Ahmadu Bello University department of Chemistry Ahmadu Bello University

AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHOdS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 *** In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique pr

关键词： Extraction techniques Microwave-assistedextraction Maceration Phytoconstituents Medicinal plants Soxhlet Anti-diabetes

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Array (Smart) Antennas Improve GSM Performance

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International Journal of Communications, Network and System Sciences 2024年第1期17卷 1-10页

作者： Cornelius A. d. Pahalson Nuhu habila Hyat Markus Gaga department of Science School of Science and Technology Plateau State Polytechnic Barkin Ladi Nigeria

As wireless data applications over cellular networks become more widespread, the pressure to increase capacity will become even more intense. Capacity in the 800 and 900 MHz bands, where bandwidth is restricted, is already becoming a limiting factor. This paper attempts to address how the application of smart antenna systems has brought about improvements in call quality and increased capacity through reduced Interference in Mobile Communication. The smart antenna may be in a variety of ways to improve the performance of a communications system. Perhaps most importantly is its capability to cancel co-channel interference. It helps in improving the system performance by increasing the channel capacity, spectrum efficiency, extending range coverage, speech quality, enabling tighter reuse of frequencies within a cellular network and economically, feasible increased signal gain, greater, reduced multipath reflection. It has been argued that Smart antennas and the Algorithms to control them are vital to a high-capacity communication system development.

关键词： GSM Signal Quality Smart Antenna Carrier-to-Interference Ratio Co-Channel Interference

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Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.d.james J.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

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Competitive interactions and coexistence of sympatric flagship carnivores in Asia

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Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin LI Jiayu LU Xiaoyi SHI Li’an dUO james L.d.SMITH Tianming WANG Tianjin Key Laboratory of Conservation and Utilization of Animal diversity College of Life SciencesTianjin Normal UniversityTianjinChina department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key Laboratory for Biodiversity Science and Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National Forestry and Grassland Administration Key Laboratory for Conservation Ecology of Northeast Tiger and Leopard BeijingChina

Understanding the competition and coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics and competition between tigers(Panthera tigris)and leopards(***)span decades,there is a lack of understanding regarding the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative and interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers and leopards and tested the influence of biotic and abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers and *** and ungulate density were the most important predictors in regulating the coexistence *** and leopards exhibited more positive relations/higher overlaps as elevation increased in the spatial *** addition,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers and leopards was less frequently observed in habitats with dense tree cover and homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions and coexistence mechanisms of tigers and leopards on a broad ***-makers and managers should pay more attention to the factors of elevation,prey abundance,and habitat structures for the conservation of tigers and leopards.

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition

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Functionalization of cellulose carbon dots with different elements(N,B and S)for mercury ion detection and anti-counterfeit applications

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Chinese Chemical Letters 2024年第7期35卷 355-359页

作者： Xiaoning Li Quanyu Shi Meng Li Ningxin Song Yumeng Xiao Huining Xiao Tony d.james Lei Feng Second Affiliated Hospital of dalian Medical University Dalian 116023China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science and EngineeringNorth China Electric Power UniversityBaoding 071003China department of Chemical Engineering and Limerick Pulp&Paper Centre University of New Brunswick15 Dineen DriveFredericton NB E3B 5A3Canada department of Chemistry University of BathBath BA27AYUnited Kingdom School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Mercury ion(Hg^(2+)),as one of the most toxic heavy metal ions,accumulates easily in the environment,which can generate potential hazards to the ecosystem and human *** effectively detect and remove Hg^(2+),we fabricated four types of carbon dots(Cds)using carboxymethyl nanocellulose as a carbon source doped with different elements using a hydrothermal *** the Cds exhibited a strong fluorescence emission,excitation-dependent emission and possessed good water ***,the four fluorescent Cds were used for Hg^(2+)recognition in aqueous solution,where the Cds-N exhibited better sensitivity and selectivity for Hg^(2+)detection,with a low limit of detection of 8.29×10^(-6)mol/*** was determined that the fluorescence quenching could be ascribed to a photoinduced charge-transfer processes between Hg^(2+)and the *** addition,the Cds-N were used as a smart invisible ink for anticounterfeiting,information encryption and ***,the Cds-N were immersed into a cellulose(CMC)-based hydrogel network to prepare fluorescent hydrogels capable of simultaneously detecting and adsorbing Hg^(2+).We anticipate that this research will open possibilities for a green method to synthesize fluorescent Cds for metal ion detection and fluorescent ink production.

关键词： Carbon dots Functional groups Hg^(2+)detection Mechanism Anti-counterfeiting

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Nickel sulfate solution fluoride separation with hydrous zirconium oxide

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Tungsten 2024年第2期6卷 367-381页

作者： Elbert M.Nigri Ummul K.Sultana André L.A.Santos james W.Vaughan Sonia d.F.Rocha department of Mining Engineering Federal University of Minas GeraisBelo Horizonte 31270-901Brazil School of Chemical Engineering University of QueenslandSt Lucia 4072Australia

Fluoride is an impurity in nickel sulfate production,which is required for electric vehicle *** zirconium oxide(HZO)was evaluated for removing fl uoride from nickel sulfate *** fluoride removal occurred at pH value 4 and optimal pH value is 4–5,considering Zr *** availability decreases with pH due to hydrogen fluoride and zirconium fluoride aqueous *** removal is initially rapid,with 50 wt.%removal in 7 min,followed by slow removal up to 68 wt.%after 72 h and follows second order rate *** removal was dominated by an ion exchange mechanism and resulting Zr–F bonds were observed using Fourier-transform infrared *** presence of nickel sulfate decreased loading capacity compared to a salt-free *** maintained adsorption capacity through five cycles of loading and regeneration.

关键词： Hydrous zirconium oxide Nickel sulfate Fluoride Adsorption Anion exchange

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Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells

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Energy & Environmental Materials 2024年第2期7卷 240-248页

作者： Jing Zhang james Mcgettrick Kangyu Ji Jinxin Bi Thomas Webb Xueping Liu dongtao Liu Aobo Ren Yuren Xiang Bowei Li Vlad Stolojan Trystan Watson Samuel d.Stranks Wei Zhang Advanced Technology Institute(ATI) University of SurreyGuildfordSurrey GU27XHUK SPECIFIC College of EngineeringSwansea UniversityBay Campus SA18ENSwansea UK Cavendish Laboratory University of CambridgeJ JThomson AvenueCambridge CB30HEUK department of Chemical Engineering&Biotechnology University of CambridgePhilippa Fawcett DriveCambridge CB30ASUK

Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based ***,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge *** further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport *** to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced *** addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability.

关键词： fast and balanced charge transfer inverted perovskite solar cells long-term stability low-temperature processing metal oxides

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A Cover-Independent deep Image Hiding Method Based on domain Attention Mechanism

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Computers, Materials & Continua 2024年第3期78卷 3001-3019页

作者： Nannan Wu Xianyi Chen james Msughter Adeke Junjie Zhao School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China School of Electronics and Information Engineering Nanjing University of Information Science and TechnologyNanjing210044China

Recently,deep image-hiding techniques have attracted considerable attention in covert communication and high-capacity information ***,these approaches have some *** example,a cover image lacks self-adaptability,information leakage,or weak *** address these issues,this study proposes a universal and adaptable image-hiding ***,a domain attention mechanism is designed by combining the Atrous convolution,which makes better use of the relationship between the secret image domain and the cover image ***,to improve perceived human similarity,perceptual loss is incorporated into the training *** experimental results are promising,with the proposed method achieving an average pixel discrepancy(APd)of 1.83 and a peak signal-to-noise ratio(PSNR)value of 40.72 dB between the cover and stego images,indicative of its high-quality ***,the structural similarity index measure(SSIM)reaches 0.985 while the learned perceptual image patch similarity(LPIPS)remarkably registers at ***,self-testing and cross-experiments demonstrate the model’s adaptability and generalization in unknown hidden spaces,making it suitable for diverse computer vision tasks.

关键词： deep image hiding attention mechanism privacy protection data security visual quality

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Synthesis of carbon nitride in potassium hydroxide molten salt for efficient uranium extraction from radioactive wastewater

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 89-99页

作者： Shuang Liu Junhan Luo daniel-james Maguire Liyuan Zheng Zhe Wang Yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea department of Earth Sciences University of CambridgeCambridge CB23EQUK The MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China

Photocatalysis-assisted removal of uranium has been proven as an effective method for the elimination of radioactive pollution from *** this work,carbon nitride materials were synthesized in potassium hydroxide(KOH)molten salt and applied to photocatalytic uranyl *** materials were confirmed to possess the triazine-s-heptazine structure by NMR,XPS and UV-Vis characterization,and exhibited a wider visible light absorption than graphitic carbon nitride(g-C_(3)N_(4)).The photocatalytic activity of the carbon nitride materials was tailored by varying the precursor mass *** carbon nitride obtained at 80%melamine as precursor(K-CN-80)exhibited the highest photocatalytic extraction ability and its photocatalytic reaction rate is 6.6 times faster than that of g-C_(3)N_(4).The influence of sacrificial agents was studied and the results showed that triethanolamine inhibited U(Ⅵ)photoreduction,but methanol can accelerate U(Ⅵ)photoreduction by consuming photogenerated *** unary KOH molten salt synthesis method has exceptional potential applications in the preparation of carbon nitrides,and the obtained products showed potential in extracting U(Ⅵ)from aqueous solutions for use in nuclear fuel industry and for U(Ⅵ)environmental pollution cleanup.

关键词： Uranium Carbon nitride Molten salt Photocatalysis Radioactive wastewater

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Boosting Adversarial Training with Learnable distribution

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Computers, Materials & Continua 2024年第3期78卷 3247-3265页

作者： Kai Chen Jinwei Wang james Msughter Adeke Guangjie Liu Yuewei dai School of Electronics and Information Engineering Nanjing University of Information Science and TechnologyNanjing210044China Key Laboratory of Intelligent Support Technology for Complex Environments Ministry of EducationNanjing210044China School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Nanjing Center for Applied Mathematics Nanjing211135China

In recent years,various adversarial defense methods have been proposed to improve the robustness of deep neural *** training is one of the most potent methods to defend against adversarial ***,the difference in the feature space between natural and adversarial examples hinders the accuracy and robustness of the model in adversarial *** paper proposes a learnable distribution adversarial training method,aiming to construct the same distribution for training data utilizing the Gaussian mixture *** distribution centroid is built to classify samples and constrain the distribution of the sample *** natural and adversarial examples are pushed to the same distribution centroid to improve the accuracy and robustness of the *** proposed method generates adversarial examples to close the distribution gap between the natural and adversarial examples through an attack algorithm explicitly designed for adversarial *** algorithm gradually increases the accuracy and robustness of the model by scaling ***,the proposed method outputs the predicted labels and the distance between the sample and the distribution *** distribution characteristics of the samples can be utilized to detect adversarial cases that can potentially evade the model *** effectiveness of the proposed method is demonstrated through comprehensive experiments.

关键词： Adversarial training feature space learnable distribution distribution centroid

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