fluorine-doped tin oxide (fTO) thin films were deposited on glass substrates using ultrasonic spray pyrolysis (USP) at a fixed substrate temperature of 400 degrees C and various fluorine/Tin (f/Sn) atomic ratios of 0,...
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fluorine-doped tin oxide (fTO) thin films were deposited on glass substrates using ultrasonic spray pyrolysis (USP) at a fixed substrate temperature of 400 degrees C and various fluorine/Tin (f/Sn) atomic ratios of 0, 0.1, 0.5, and 1.0. Effects off/Sn atomic ratios on structural-morphological, compositional, electrical, optical, and nanomechanical properties of the fTO thin films were systematically studied. The fTO films exhibited a tetragonal structure with preferred orientations of (110), (200), and (211), and polycrystalline morphology with spear-like or coconut shell-like particles on the surfaces. The presence off-doping was confirmed by XPS results with clear f1s peaks, and f-concentration was determined to be 0.7% for f/Sn = 0.1 and 5.1% for f/Sn = 0.5. Moreover, the resistivity offTO films reduced remarkably from 4.1 mcm at f/Sn = 0 to 0.7 mcm at f/Sn = 1, primarily due to the corresponding increase of carrier concentration from 2 x 10(20) cm(-3) to 1.2 x 10(21) cm(-3). The average optical transmittance of the films prepared at f/Sn of 0-0.5 was over 90%, and it decreased to 84.4% for the film prepared at f/Sn = 1. The hardness (H) and Young's modulus (E) of the fTO films increased when the f/Sn ratios increased from 0 to 0.5, reaching maximum values of H = 12.3 +/- 0.4 GPa, E = 131.7 +/- 8.0 GPa at f/Sn = 0.5. Meanwhile, the H and E reduced considerably when the f/Sn ratio further increased to 1.0, following the inverse Hall-Petch effect approximately, suggesting that the grain boundary effect played a primary role in manipulating the nanomechanical properties of the fTO films. furthermore, favorable mechanical properties with large H/E-f and ratios were found for the fTO film prepared at f/Sn = 0.5, which possessed high crystallinity, large grain size, and compact morphology.
In this research, a novel Ag 3 PO 4 [email protected] 2 nanosheet-based electrochemiluminescence (ECL) sensing system was developed to provide an effective method for tumor gene detection. At first, fluorine, sul...
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In this research, a novel Ag 3 PO 4 [email protected] 2 nanosheet-based electrochemiluminescence (ECL) sensing system was developed to provide an effective method for tumor gene detection. At first, fluorine, sulfur-doped BN quantum dot (f, S-BN QD) were prepared as ECL emitter. Sulfur dopant can provide more reactive sites in the ECL reaction. fluorine atoms in the QD structure further improved the stability of the crystal. furthermore, Ag 3 PO 4 [email protected] 2 nanosheets were fabricated via a hydrothermal route as ECL reaction catalyst. On the one hand, Ag 3 PO 4 [email protected] 2 nanosheets promoted the generation of more oxidant of coreactant in the f, S-BN QD/H 2 O 2 coreactant ECL pathway. On the other hand, the excellent conductivity of Ag 3 PO 4 [email protected] 2 nanosheets facilitated the electron transfer and effectively reduce the damage off, S-BN QD by excessive hot electrons. finally, the proposed biosensor was designed to accurately quantify K-ras tumor gene from 10 fM to 100 pM with a limit of detection (LOD) of 0.2 fM. The sensing system was used to detect K-ras gene in human colorectal cancer tumor and tumor-adjacent tissues samples with satisfactory results. The amplified ECL sensing strategy with Ag 3 PO 4 [email protected] 2 nanosheet has significant potential value in the clinical detection.
f-420-dependent glucose-6-phosphate dehydrogenase (fGD) is involved in the committed step of the pentose phosphate pathway within mycobacteria, where it catalyzes the reaction between glucose-6-phosphate (G6P) and the...
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f-420-dependent glucose-6-phosphate dehydrogenase (fGD) is involved in the committed step of the pentose phosphate pathway within mycobacteria, where it catalyzes the reaction between glucose-6-phosphate (G6P) and the f-420 cofactor to yield 6-phosphogluconolactone and the reduced cofactor, f420H2. Here, we aim to probe the fGD reaction mechanism using dead-end inhibition experiments, as well as solvent and substrate deuterium isotope effects studies. The dead-end inhibition studies performed using citrate as the inhibitor revealed competitive and uncompetitive inhibition patterns for G6P and f-420 respectively, thus suggesting a mechanism of ordered addition of substrates in which the f-420 cofactor must first bind to fGD before G6P binding. The solvent deuterium isotope effects studies yielded normal solvent kinetic isotope effects (SKIE) on kcat and k(cal)/K-m for both G6P and f-420. The proton inventory data yielded a fractionation factor of 0.37, suggesting that the single proton responsible for the observed SKIE is likely donated by Glu109 and protonates the cofactor at position Ni. The steady state substrate deuterium isotope effects studies using G6P and G6P-d(1) yielded KIE of 1.1 for both koo, and K-cat/K-m while the pre-steady state KIE on k(obs), was 1.4. Because the hydride transferred to C5 off-420 was the one targeted for isotopic substitution, these KIE values provide further evidence to support our previous findings that hydride transfer is likely not rate-limiting in the fGD reaction.
Christoph Jager (Erkenntnis 61:187-201, 2004) has argued that Dretske's (Knowledge and the flow of Information, MIT Press, Cambridge, 1981) information-based account of knowledge is committed to both knowledge and...
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Christoph Jager (Erkenntnis 61:187-201, 2004) has argued that Dretske's (Knowledge and the flow of Information, MIT Press, Cambridge, 1981) information-based account of knowledge is committed to both knowledge and information closure under known entailment. However, in a reply to Jager, Dretske (Erkenntnis 64:409-413, 2006) defended his view on the basis of a discrepancy between the relation of information and the relation of logical implication. This paper shares Jager's criticism that Dretske's externalist notion of information implies closure, but provides an analysis based on different grounds. By means of a distinction between two perspectives, the mathematical perspective and the epistemological perspective, I present, in the former, a notion of logical implication that is compatible with the notion of information in the mathematical theory of information, and I show how, in the latter, Dretske's logical reading of the closure principle is incompatible with his information-theoretic epistemological framework.
High temperature interaction of Lif-Nif2 system is characterized with the ternary compound, Li2Nif4(s). The compound has been synthesized by solid state route. Li2Nif4(s) has been characterized with XRD technique and ...
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High temperature interaction of Lif-Nif2 system is characterized with the ternary compound, Li2Nif4(s). The compound has been synthesized by solid state route. Li2Nif4(s) has been characterized with XRD technique and its micro-homogeneity and surface morphology have been tested with EDS and SEM technique, respectively. In order to study the thermodynamic stability, the Gibbs energy offormation, Delta(f)G degrees(m)(T), of Li2Nif4(s) has been measured with solid electrolyte galvanic cell technique and its measured Delta(f)G degrees(m)(T) can be expressed as Delta(f)G degrees(m)(T) [Li2Nif4(s)] / k.J mol(-1) = (-1902.2 +/- 1.1) + (0.3491 +/- 0.0016) x (T/K). Using the experimental thermodynamic data, ternary phase diagram and fluorine potential diagram of Li-Ni-f-2 system have been calculated in order to study the stability domain and coexisting phases of Li2Nif4(s) at reactor operating temperature. The stability of Li2Nif4(s) has also been investigated in the presence of oxygen impurity by calculating chemical potential diagram of Li-Ni-f-O system and ternary phase diagram of Lif-Nif2-O-2 system at the same temperature. In the study, interaction of major structural components, Ni, Cr, and fe, with fuel salt components (Thf4 and Uf4) of MSR has also been investigated at different temperatures.
目的克隆、表达粉尘螨Der f 32蛋白,并鉴定其免疫原性及其对树突状细胞(DC)的调节作用。方法合成粉尘螨过敏原Der f 32基因,与pET-24a(+)载体连接,转入大肠埃希菌BL21诱导表达,经亲和层析法纯化后,十二烷基硫酸钠-聚丙烯酰氨凝胶电泳(SD...
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目的克隆、表达粉尘螨Der f 32蛋白,并鉴定其免疫原性及其对树突状细胞(DC)的调节作用。方法合成粉尘螨过敏原Der f 32基因,与pET-24a(+)载体连接,转入大肠埃希菌BL21诱导表达,经亲和层析法纯化后,十二烷基硫酸钠-聚丙烯酰氨凝胶电泳(SDS-PAGE)分析重组蛋白表达情况,蛋白质印迹(Western blotting)、临床皮肤点刺实验检测重组蛋白的免疫原性。将重组蛋白Der f 32与小鼠来源的DC2.4共培养24 h,设阳性对照组(加等量重组蛋白Der f 1)和阴性对照组(加等量PBS),流式细胞术检测细胞表面共刺激分子(CD40、 CD83和CD80)的表达。将重组蛋白稀释为10、 20、 30、 40、 50、 60μg/ml等不同浓度,分别与DC2.4共培养48 h后, Western blotting分析T细胞免疫球蛋白及黏蛋白域蛋白4 (TIM4)的表达情况。结果SDS-PAGE结果显示,重组蛋白Der f 32相对分子质量(Mr)约35 000。临床皮肤点刺实验表明, 42位尘螨过敏患者中有6例对重组蛋白Der f 32过敏,阳性率为14.2%。Western blotting结果显示,重组蛋白Der f 32能与皮试阳性患者血清IgE抗体特异性结合。流式细胞术检测结果显示,重组蛋白Der f 32与DC2.4共培养后, CD40、 CD83、 CD80的表达水平分别为24.5%、 9.6%和24.6%,高于阴性对照组(11.9%、 3.1%和15.6%)(P <0.01),低于阳性对照组(38.2%、 15.0%和39.1%)(P <0.05)。Western blotting检测结果显示, TIM4的表达量随重组蛋白Der f 32浓度的升高逐渐增加,且在Der f 32浓度为50μg/ml时, TIM4的表达量达到最高, TIM4相对灰度值为1.112。结论获得了具有较强免疫原性的粉尘螨新过敏原Der f 32,该蛋白能促进DC表面分子和TIM4的表达。
Rice bakanae is an important disease that causes serious rice production loss worldwide. We describe a new method for rapid diagnosis of rice bakanae caused by fusarium fujikuroi and ***, based on loop-mediated isothe...
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Rice bakanae is an important disease that causes serious rice production loss worldwide. We describe a new method for rapid diagnosis of rice bakanae caused by fusarium fujikuroi and ***, based on loop-mediated isothermal amplification (LAMP) assays. After screening, primers were selected to target fusariumDNA sequences, that is, the intergenic spacer (IGS) region of the nuclear ribosomal operon and reductase-coding region (RED1) in *** and ***, respectively. Both LAMP assays efficiently amplified target genes in 70min at 62 degrees C. A colour change from purple to sky blue (visible to the unaided eye) was observed in the presence of the DNA of the targeted pathogens only, by adding hydroxynaphthol blue to the reaction system prior to amplification. The minimum of genomic DNA needed in the assays was 67 and 346pg/l for *** and ***, respectively. Using the two assays described here, we successfully and rapidly diagnosed suspected diseased rice plant and seed samples collected from Jiangsu Province.
This study deals with the extraction and testing of natural cellulose fibers obtained from the barks of Ziziphus nummularia (Burm. f.) Wight & Arn. plants. The extraction of Z. nummularia fibers from its plant bar...
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This study deals with the extraction and testing of natural cellulose fibers obtained from the barks of Ziziphus nummularia (Burm. f.) Wight & Arn. plants. The extraction of Z. nummularia fibers from its plant barks was done by water retting. The extracted fibers were analyzed for their chemical, crystalline, thermal, mechanical, and physical properties. Surface characteristics of the fibers were examined using a scanning electron microscope and an atomic force microscope. The test results showed that cellulose content was 52.34%. The crystalline index was 45.77% whereas the crystallite size was 2.01 nm. Thermogravimetric analysis showed a maximum degradation temperature of 348 degrees C. The morphological properties showed that Z. nummularia fibers had a good surface roughness that helps in forming interlocks with the matrix on its usage in polymer matrix composites.
This paper investigates the input-to-state contraction for impulsive systems. The notion of input-to-state contraction (ISC) is proposed via incremental input-to-state stability (delta ISS). By using the method of var...
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This paper investigates the input-to-state contraction for impulsive systems. The notion of input-to-state contraction (ISC) is proposed via incremental input-to-state stability (delta ISS). By using the method of variation, the equivalence between global ISC and exponential delta ISS is established. Then by the technique of the average dwell-time (ADT), some criteria for global ISC and exponential delta ISS are derived for impulsive systems. Moreover, by using impulse frequency (I.f.) to replace ADT, the criteria are improved and less conservative criteria via I.f. are established for global ISC and exponential delta ISS. The criteria are used to derive global ISC and exponential delta ISS for continuous and discrete time systems. Discussions are given to relax the differentiable vector fields. And the criteria of exponential delta ISS via the Lyapunov-like function are derived for impulsive systems satisfying time-varying Lipschitz condition. finally, three examples are worked out for illustrations, where impulsive control is designed for chaotic systems to achieve global ISC.
A well-known cartoon among psychologists and behavior analysts depicts two rats in a Skinner box, leaning over a response lever as one says to the other, "Boy, do we have this guy conditioned, every time I press ...
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A well-known cartoon among psychologists and behavior analysts depicts two rats in a Skinner box, leaning over a response lever as one says to the other, "Boy, do we have this guy conditioned, every time I press the bar down he drops a pellet in." Anyone who has ever conducted an experiment, worked with a client, or taught someone can relate to the cartoon's message of reciprocal control between subject and experimenter, client and therapist, and teacher and student. This is the tale of that cartoon and its impact. It begins mid-20(th)-century at Columbia University, then a hotbed of behavioral psychology, which bears an intimate connection to the cartoon's appearance. The tale expands from Columbia to follow the lives of its creators from their undergraduate days there to their deaths decades later. The infusion of the cartoon into American psychology begins with B. f. Skinner, but, over the years, it also has appeared in introductory psychology textbooks and in iterative form in mass media outlets such as the World Wide Web and magazines like The New Yorker. The heart of the tale, however, was stated in the second sentence of this abstract. The tale ends with a review of how reciprocal relations like those depicted by the cartoon's creators have influenced research and practice in behavioral psychology.
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