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Synthesis of highly fluorescent carbon dots from lemon and onion juices for determination of riboflavin in multivitamin/mineral supplements

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Journal of Pharmac.u.ical Analysis 2019年第3期9卷 209-216页

作者： Severino S. Monte-Filho Stefani I.E. Andrade Marcelo B. Lima mario c.u. araujo universidade Federal da Paraíba CCEN Departamento de Química P.O. Box 5093 Zip Code 58051-970 Joao Pessoa PB Brazil universidade Federal Rural de Pernambuco-unidade Acad^emica de Serra Talhada UAST Zip Code 56909-535 Serra Talhada PE Brazil

In this work, lemon and onion biomasses commonly found in street markets are for the first time used to develop a facile, fast and low-cost one-step microwave-assisted carbonization method for synthesis of highly fluorescent carbon dots (cDs). The struc.u.e and optical properties of cDs were investigated by TEM, XRD, XRF, uV-Vis, FTIR, and fluorescence spectroscopy. cDs displayed satisfactory optical pro-prieties, a high quantum yield of 23.6%, and excellent water solubility, and the particle size was 4.23-8.22 nm with an average diameter of 6.15 nm. An efficient fluorescent resonance energy transfer (FRET) between the cDs and riboflavin was achieved with cDs acting as donor and riboflavin as acceptor. A linear relationship between FRET and the riboflavin concentration from 0.10 to 3.0 μg/mL was observed, allowing the development of an ac.u.ate and fast analytical method to determine this vitamin in multivitamin/mineral supplements. Despite the potential interferences in these supplements, cDs were selective for riboflavin under optimized conditions. A paired t-test at a 95% confidence level indicated no statistically significant difference between the proposed and the reference methods. Recovery test presented values ranged from 96.0% to 101.4%. The limit of detection and relative standard deviation were estimated at 1.0 ng/mL and ctively. cDs were successfully synthesized in a domestic microwave oven (1450 W, 6 min), presenting satisfactory parameters when compared with results of other studies reported in the literature, suggesting that the proposed method is a potentially useful method for the synthesis of cDs and determination of riboflavin.

关键词： carbon dots Microwave-assisted carbonization Lemon-onion juice Riboflavin Multivitamin/mineral supplements Fluorescence

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Metal Organic chemical Vapour Deposited Thin Films of cobalt Oxide Prepared via cobalt Acetylacetonate

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Journal of Materials Science & Technology 2009年第1期25卷 85-89页

作者： c.u. Mordi M.A. Eleruja B.A. Taleatu G.O. Egharevba A.V. Adedeji O.O. Akinwunmi B. Olofinjana c. Jeynes E.O.B. Ajayi Department of Physics Obafemi Awolowo University Ile-Ife Nigeria Department of chemistry Obafemi Awolowo University Ile-Ife Nigeria Department of Physics Auburn University Alabama United States Department of Electronics and Electrical Engineering University of Surrey Guildford Surrey GU2 7XH UK

The single solid source precursor, cobalt （Ⅱ） acetylacetonate was prepared and characterized by infrared spectroscopy. Thin films of cobalt oxide were deposited on soda lime glass substrates through the pyrolysis （metal organic chemical vapour deposition （MOcVD）） of single solid source precursor, cobalt acetylacetonate, co[c5H7O2]2 at a temperature of 420℃. The compositional characterization carried out by rutherford backscattering spectroscopy and X-ray diffraction （XRD）, showed that the films have a stoichiometry of co2O3 and an average thickness of 227±0.2 nm. A direct energy gap of 2,15±0.01 eV was calculated by the data obtained by optical absorption spectroscopy. The morphology of the films obtained by scanning electron microscopy, showed that the grains were continuous and uniformly distributed at various magnifications, while the average grain size was less than i micron for the deposited thin films of cobalt oxide.

关键词： Precursor Thin film Oxide Metal organic chemical vapour deposition (MOcVD) Rutherford backscattering spectroscopy (RBS)

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Semi-solid near-net shape rheocasting of heat treatable wrought aluminum alloys

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Transactions of Nonferrous Metals Society of china 2010年第9期20卷 1719-1724页

作者： u.A.c.u.LE Materials Science and Manufac.u.ing Council for Scientific and Industrial Research

Flexibility of the cSIR-RcS, induction stirring with simultaneous air cooling process, in combination with high pressure die casting is successfully demonstrated by semi-solid rheocasting of plates performed on commercial 2024, 6082 and 7075 wrought aluminum alloys. Tensile properties were measured for the above mentioned rheocast wrought aluminum alloys in the T6 condition. The results showed that tensile properties were close to or even in some cases exceeded the minimum specifications. The yield strength and elongation of rheocast 2024-T6 exceeded the minimum requirements of the wrought alloy in the T6 condition but the ultimate tensile strength achieved only 90% of the specification bec.u.e the Mg content of the starting alloy was below the commercial alloy specification. The strengths of rheocast 6082-T6 exceeded all of the wrought alloy T6 strength targets but the elongation only managed 36% of the required minimum due to porosity, c.u.ed by incipient melting during solution heat treatment, and the presence of fine intermetallie needles in the eutectic. The yield strength of rheocast 7075 exceeded the required one and the ultimate tensile strength also managed 97% of the specification; while the elongation only reached 46% of the minimum requirement also due to incipient melting porosity c.u.ed during the solution heat treatment process.

关键词： high pressure die casting (HPDc) aluminum alloys as-cast condition T6 treatment incipient melting

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combination approaches in hepatocellular carcinoma:How systemic treatment can benefit candidates to locoregional modalities

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World Journal of Gastroenterology 2022年第28期28卷 3573-3585页

作者： Leonardo Gomes da Fonseca Raphael L c araujo Department of Medical Oncology Instituto do Cancer do Estado de Sao PauloUniversity of Sao PauloSão Paulo 01246-000São PauloBrazil Hospital e Maternidade Brasil-Rede D'Or São Luiz Santo André09030-590São PauloBrazil Department of Digestive Surgery Escola Paulista de Medicina-UNIFESPSão Paulo 04023-062São PauloBrazil

The management of hepatocellular carcinoma(Hcc)is challenging bec.u.e most patients have underlying cirrhosis,and the treatment provides,historically,a limited impact on the natural history of patients with advanced-stage ***,recurrence rates are high for those patients who receive local and locoregional modalities,such as surgical(resection and transplantation)or imageguided(ablation and intra-arterial)*** research has led to new concepts that are reshaping the current clinical *** advancements were achieved in the understanding of the hallmarks that drive *** has primed a successful incorporation of novel agents with different targets,such as anti-angiogenic drugs,targeted-therapies,and immune-checkpoint *** clinical trials have proven efficacy of systemic agents in advanced stage disease,there is no conc.u.ive evidence to support their use in combination with loco-regional *** novel local modalities are being incorporated(e.g.,radioembolization,microwave ablation,and irreversible electroporation),emerging data indicate that locoregional treatments may induce tumor microenvironment changes,such as hyperexpression of growth factors,release of tumor antigens,infiltration of cytotoxic lymphocytes,and modulation of adaptative and innate immune *** trials that evaluated the use of antiangiogenic drugs in the adjuvant setting after ablation or chemoembolization fail to demonstrate a substantial *** efforts are directed to investigate the role of immunotherapy-based regimens in this *** present review aims to describe the current landscape of systemic and locoregional treatments for Hcc,present evidence to support combination approaches,and address future perspectives.

关键词： Liver cancer Hepatocellular carcinoma Immunotherapy Systemic therapy Ablation Embolization

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Genome-wide identification and in silico gene expression analysis of the related to ABI3/VP1(RAV)transcription factor family in barley(Hordeum vulgare L.)

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BIOcELL 2021年第6期45卷 1673-1685页

作者： cÜNEYT uÇARLI Department of Molecular Biology and Genetics Istanbul UniversityIstanbul34134Turkey

RAV(Related to ABI3/VP1)transcription factors are unique members of the AP2-ERF superfamily with AP2 and B3 domains and play important roles in the regulation of seed germination,plant growth,and stress *** the study,7 RAV genes,named HvRAVs,were identified in barley based on the available genome *** five of the seven HvRAVs were located on chromosome 3,HvRAV5 and HvRAV7 were located on chromosome 1 and 4,*** of the predicted HvRAVs were intron-less,except HvRAV2,which had one *** proteins have shown basic,instable,and hydrophilic *** AP2 domain specific RAYD and WLG motifs were detected in all HvRAV ***,B3 repression domain,R/KLFGV,is also found in the c-terminal of *** were found to have stress-related cis-acting elements,inc.u.ing MYB,MYc,and ***2 was predicted to have no GARE motifs,TATcccA or TAAcAA(G/A),and *** drought conditions,the expression level of HvRAVs did not significantly change in a drought-sensitive barley genotype,whereas HvRAV5 and HvRAV7 were dramatically down-regulated in a drought-tolerant *** of HvRAV5 was also inhibited by ***7 was strongly induced by plant pathogen *** HvRAV6 was induced by exogenous gibberellin application and during the germination ***,HvRAV6 transcript was detected higher than other HvRAVs in all stress and control conditions as well as during *** silico analyses have shown that HvRAVs play a role in response to different abiotic and biotic stresses as well as in plant ***,the extensive biological roles of HvRAV genes in plant development and in response to abiotic and biotic stresses need further investigation.

关键词： Barley RAV AP2 domain B3 domain AP2/ERF family cis-acting elements

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Sources and Deficiency Diseases of Mineral Nutrients in Human Health and Nutrition:A Review

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Pedosphere 2014年第1期24卷 13-38页

作者： u.c.GuPTA S.c.GuPTA Agriculture and Agri-canada canada Crops and Livestock Research Centre The Department of Plastic Surgery Loma Linda University

Mineral nutrients are fundamentally metals and other inorganic compounds. The life cycle of these mineral nutrients begins in soil, their primary source. Soil provides minerals to plants and through the plants the minerals go to animals and humans; animal products are also the source of mineral nutrients for humans. Plant foods contain almost all of the mineral nutrients established as essential for human nutrition. They provide much of our skeletal struc.u.e, e.g., bones and teeth. They are critical to c.u.tless body processes by serving as essential co-factors for a number of enzymes. Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption. Though mineral nutrients are essential nutrients, the body requires them in small, precise amounts. We require them in the form found in crops and they can be classified into three different categories： major, secondary, and micro or trace minerals. This classification is based upon their requirement rather than on their relative importance. Major minerals such as potassium （K） and phosphorus （P） are required in amounts of up to 10 g d-1. The daily requirement of secondary and micro minerals ranges from 400 to 1 500 mg d-1 and 45 ~tg d-1 to 11 mg d-1, respectively. To protect humans from mineral nutrient deficiencies, the key is to consume a variety of foods in modest quantities, such as different whole grains, low fat dairy, and different meats, vegetables and fruits. For insurance purposes, a supplement containing various mineral nutrients can be taken daily.

关键词： deficiency diseases deficiency symptoms origin recommended daily dose toxicity

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Effect of benzaldehyde on the electrodeposition and corrosion properties of Ni–W alloys

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1060-1066页

作者： u.Pramod Kumar c.Joseph Kennady Department of chemistry Karunya Institute of Technology and SciencesKarunya NagarCoimbatore 641114Tamil NaduIndia

The effect of different concentrations of benzaldehyde on the electrodeposition of Ni–W alloy coatings on a mild steel substrate from a citrate electrolyte was investigated in this study. The electrolytic alkaline bath(p H 8.0) contained stoichiometric amounts of nickel sulfate, sodium tungstate, and trisodium citrate as precursors. The corrosion resistance of the Ni–W-alloy-coated specimens in 0.2 mol/L H2SO4 was studied using various electrochemical techniques. Tafel polarization studies reveal that the alloy coatings obtained from the bath containing 50 ppm benzaldehyde exhibit a protection efficiency of 95.33%. The corrosion rate also decreases by 21.5 times compared with that of the blank. A higher charge-transfer resistance of 1159.40 ?·cm2 and a lower double-layer capacitance of 29.4 μF·cm-2 further confirm the better corrosion resistance of the alloy coating. X-ray diffraction studies reveal that the deposits on the mild steel surface are consisted of nanocrystals. A lower surface roughness value(Rmax) of the deposits is confirmed by atomic force microscopy.

关键词： nickel–tungsten alloys benzaldehyde electrodeposit

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Exact solution of Dirac equation for Scarf potential with new tensor c.u.ling potential for spin and pseudospin symmetries using Romanovski polynomials

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chinese Physics B 2014年第9期23卷 71-80页

作者： A.Suparmi c.cari u.A.Deta Physics Department Faculty of Mathematics and Natural ScienceSebelas Maret University Department of Physics Faculty of Mathematics and Natural ScienceState University of Surabaya

The bound state solutions of Dirac equations for a trigonometric Scarf potential with a new tensor potential under spin and pseudospin symmetry limits are investigated using Romanovski polynomials. The proposed new tensor potential is inspired by superpotential form in supersymmetric （SuSY） quantum mechanics. The Dirac equations with trigonometric Scarf potential c.u.led by a new tensor potential for the pseudospin and spin symmetries reduce to Schrtdinger-type equations with a shape invariant potential since the proposed new tensor potential is similar to the superpotential of trigonometric Scarf potential. The relativistic wave functions are exactly obtained in terms of Romanovski polynomials and the relativistic energy equations are also exactly obtained in the approximation scheme of centrifugal term. The new tensor potential removes the degeneracies both for pseudospin and spin symmetries.

关键词： Scarf potential new tensor potential spin and pseudospin symmetries Romanovski polynomials

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The hidden half comes into the spotlight: Peeking inside the black box of root developmental phases

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Plant communications 2022年第1期3卷 36-52页

作者： Joao Antonio Siqueira Wagner c.Otoni Wagner L.araujo Departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMG 36570-900Brazil

Efficient use of natural resources(e.g.,light,water,and nutrients)can be improved with a tailored developmental program that maximizes the lifetime and fitness of *** plant shoots,a developmental phase represents a time window in which the meristem triggers the development of unique morphological and physiological traits,leading to the emergence of leaves,flowers,and *** developmental phases in plant shoots have been shown to enhance food production in crops,this phenomenon has remained poorly investigated in *** light of recent advances,we suggest that root development oc.u.s in three main phases:root apical meristem appearance,foraging,and *** provide compelling evidence suggesting that these phases are regulated by at least four developmental pathways:autonomous,non-autonomous,hormonal,and *** developmental pathways differentially coordinate organ plasticity,promoting morphological alterations,tissue regeneration,and cell death ***,we suggest how nutritional checkpoints may allow progression through the developmental phases,thus completing the root life *** insights highlight novel and exciting advances in root biology that may help maximize the productivity of crops through more sustainable agriculture and the reduced use of chemical fertilizers.

关键词： developmental transitions plasticity cell fates nutritional checkpoints root development root clock

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unique immunological profile in patients with cOVID-19

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cellular & Molecular Immunology 2021年第3期18卷 604-612页

作者： Stefania Varchetta Dalila Mele Barbara Olivier Stefania Mantovani Serena Ludovisi Antonella cerino Raffaele Bruno Alberto castelli mario Mosconi Marco Vecchia Silvia Roda Michele Sachs catherine Klersy mario u.Mondelli Division of Infectious Diseases Ⅱ and Immunology Fondazione IRCCS Polidinico San MatteoPaviaItaly Department of Internal Medicine and Therapeutics University of PaviaPaviaItaly Division of Infectious Diseases I Fondazione IRCCS Polidinico San MatteoPaviaItaly Department of clinical SurgicalDiagnosticand Pediatric SciencesUniversity of PaviaPaviaItaly Division of Orthopaedics and Traumatology Fondazione IRCCS Polidinico San MatteoPaviaItaly Department of clinical-Surgical Diagnostic and Pediatric SciencesUniversity of PaviaPaviaItaly clinical Epidemiology&Biometry unit IRCCS Fondazione Polidinico San MatteoPaviaItaly

The relationship between severe acute respiratory syndrome coronavirus-2(SARS-coV-2)and host immunity is poorly *** performed an extensive analysis of immune responses in 32 patients with severe cOVID-19,some of whom suc.u.bed A control population of healthy subjects was *** with cOVID-19 had an altered distribution of peripheral blood lymphocytes,with an increased proportion of mature natural killer(NK)cells and low T-cell *** cells and cD8^(+)T cells overexpressed T-cellimmunoglobulin and mucin domain-3(TIM-3)and *** cell exhaustion was attested by increased frequencies of programmed cell death protein 1(PD-1)positive cells and reduced frequencies of natural killer group 2 member D(NKG2D)-,DNAX accessory molecule-1(DNAM-1)-and sialic acid-binding Ig-like lectin 7(Siglec-7)-expressing NK cells,associated with a reduced ability to secrete interferon(IFN)γ.Patients with poor outcome showed a contraction of immature cD56^(bright) and an expansion of mature cD57^(+)F_(cEI)Rlγ^(eng) adaptive NK cells compared to *** serum levels of IL-6 were also more frequently identified in deceased patients compared to *** note,monocytes secreted abundant quantities of IL-6,IL-8,and IL-1β which persisted at lower levels several weeks after recovery with concomitant normalization of cD69,PD-1 and TIM-3 expression and restoration of cD8^(+)T cell numbers.A hyperactivated/exhausted immune response dominate in severe SARS-coV-2 infection,probably driven by an uncontrolled secretion of inflammatory cytokines by *** findings unveil a unique immunological profile in cOVID-19 patients that will help to design effective stage-specific treatments for this potentially deadly disease.

关键词： c0VID-19 NK cells TIM-3 IL6 Monocytes

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