3,583 research outputs found

    Capacitive Control of Spontaneously Induced Electrical Charge of Droplet by Electric Field-Assisted Pipetting

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    The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting. Hence, a method for controlling and removing the electrical charge needs to be developed. In this study, by using the electrode-deposited pipet tip (E-pipet tip), the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled. The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model. Furthermore, a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications. Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled, the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet, such as the surface oscillation and evaporation of charged droplets.1143Ysciescopu

    Agrobacterium-mediated genetic transformation of Miscanthus sinensis

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    Miscanthus species are tall perennial rhizomatous grasses with C4 photosynthesis originating from East Asia, and they are considered as important bioenergy crops for biomass production. In this study, Agrobacterium-mediated transformation system for M. sinensis was developed using embryogenic calli derived from mature seeds. In order to establish a stable system, optimum conditions to obtain highly regenerable and transformation-competent embryogenic calli were investigated, and embryogenic calli were efficiently induced with callus induction medium containing 3 mg L-1 2,4-dichlorophenoxyacetic acid and 25 mM l-proline, at pH 5.7 with an induction temperature of 28 A degrees C. In addition, the embryogenic callus induction and regeneration potentials were compared between seven M. sinensis germplasms collected from several sites in Korea, which revealed that the germplasm SNU-M-045 had superior embryogenic callus induction and regeneration potentials. With this germplasm, the genetic transformation of M. sinensis was performed using Agrobacterium tumefaciens EHA105 carrying pCAMBIA1300 with a green fluorescence protein gene as a reporter. After putative transgenic plants were obtained, the genomic integration of transgenes was confirmed by genomic PCR, transgene expression was validated by Northern blot analysis, and the number of transgene integration was confirmed by DNA gel blot analysis. Furthermore, the Agrobacterium-mediated transformation of M. sinensis was also performed with pCAMBIA3301 which contains an herbicide resistance gene (BAR), and we obtained transgenic M. sinensis plants whose herbicide resistance was confirmed by spraying with BASTA(A (R)). Therefore, we have established a stable Agrobacterium-mediated transformation system for M. sinensis, and also successfully produced herbicide-resistant Miscanthus plants by introducing BAR gene via the established method.X111210Ysciescopu

    Molecular lens applied to benzene and carbon disulfide molecular beams

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    A molecular lens of the nonresonant dipole force formed by focusing a nanosecond IR laser pulse has been applied to benzene and CS2 molecular beams. Using the velocity map imaging technique for molecular ray tracing, characteristic molecular lens parameters including the focal length (f ), minimum beam width (W), and distance to the minimum beam width position (D) were determined. The laser intensity dependence of the observed lens parameters was in good agreement with theoretical predictions. W was independent of the laser peak intensity (I-0), whereas f and D varied linearly with 1/I-0. The differences in lens parameters between the molecular species were well correlated with the polarizability per mass values of the molecules. A high chromatographic resolution of Rs = 0.84 was achieved between the images of benzene molecular beams undeflected and deflected by the lens. The possibilities for a new type of chromatography are discussed.open293

    Prevalence of albuminuria and cardiovascular risk profile in a referred cohort of patients with type 2 diabetes: An Asian perspective

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    Background: Microalbuminuria (MA) is a risk marker for diabetic nephropathy and cardiovascular (CV) disease (CVD) in patients with diabetes. This study aimed to describe the prevalence of albuminuria, CV risk factors, and treatments for renal and CV protection in an Asian population with type 2 diabetes. Methods: This cross-sectional study conducted in eight Asian countries enrolled normotensive/hypertensive adults with type 2 diabetes without known proteinuria and/or non-diabetic kidney disease. Exclusion criteria were type 1 diabetes, menstruation, pregnancy, and acute fever. A single random urinary albumin/creatinine test was carried out in all patients. Results: Of 8,561 patients, 14% had diabetic retinopathy, and 17% and 21% had history of CV disease and smoking, respectively. Normoalbuminuria was seen in 44%, MA in 44%, and macroalbuminuria in 12%. Target glycosylated hemoglobin (HbA1c) (<7%) was reached in only 37% of 3,834 patients with available values. Diabetes was managed by diet alone in 6%, while others received oral hypoglycemic drugs and/or insulin. In total, 75% did not reach target blood pressure (BP) of ≤130/80 mm Hg. Antihypertensive drugs were prescribed to 52%, with the number of drugs increasing as the level of systolic BP increased. Drugs blocking the renin-angiotensin system were most commonly prescribed, followed by calcium channel blockers. Lipid-lowering drugs and anticoagulant/antiplatelet agents were used in about 30% and 25% of patients, respectively. Conclusions: Asian patients with type 2 diabetes had a high prevalence of MA and reduced kidney function. Furthermore, BP and HbA1c control was only achieved in a minority of patients. Aggressive risk management by administration of reno- and cardioprotective treatments is urgently needed. © 2008 Mary Ann Liebert, Inc.published_or_final_versio

    Full left ventricular coverage is essential for the accurate quantification of the area- at- risk by T1 and T2 mapping

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    T2-weighted cardiovascular magnetic resonance (CMR) using a 3-slice approach has been shown to accurately quantify the edema-based area-at-risk (AAR) in ST-segment elevation myocardial infarction (STEMI). We aimed to compare the performance of a 3-slice approach to full left ventricular (LV) coverage for the AAR by T1 and T2 mapping and MI size. Forty-eight STEMI patients were prospectively recruited and underwent a CMR at 4 ± 2 days. There was no difference between the AARfull LV and AAR3-slices by T1 (P = 0.054) and T2-mapping (P = 0.092), with good correlations but small biases and wide limits of agreements (T1-mapping: N = 30, R2 = 0.85, bias = 1.7 ± 9.4% LV; T2-mapping: N = 48, R2 = 0.75, bias = 1.7 ± 12.9% LV). There was also no significant difference between MI size3-slices and MI sizefull LV (P = 0.93) with an excellent correlation between the two (R2 0.92) but a small bias of 0.5% and a wide limit of agreement of ±7.7%. Although MSI was similar between the 2 approaches, MSI3-slices performed poorly when MSI was <0.50. Furthermore, using AAR3-slices and MI sizefull LV resulted in ‘negative’ MSI in 7/48 patients. Full LV coverage T1 and T2 mapping are more accurate than a 3-slice approach for delineating the AAR, especially in those with MSI < 0.50 and we would advocate full LV coverage in future studies

    Simulating quantum statistics with entangled photons: a continuous transition from bosons to fermions

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    In contrast to classical physics, quantum mechanics divides particles into two classes-bosons and fermions-whose exchange statistics dictate the dynamics of systems at a fundamental level. In two dimensions quasi-particles known as 'anyons' exhibit fractional exchange statistics intermediate between these two classes. The ability to simulate and observe behaviour associated to fundamentally different quantum particles is important for simulating complex quantum systems. Here we use the symmetry and quantum correlations of entangled photons subjected to multiple copies of a quantum process to directly simulate quantum interference of fermions, bosons and a continuum of fractional behaviour exhibited by anyons. We observe an average similarity of 93.6\pm0.2% between an ideal model and experimental observation. The approach generalises to an arbitrary number of particles and is independent of the statistics of the particles used, indicating application with other quantum systems and large scale application.Comment: 10 pages, 5 figure

    A dynamic network approach for the study of human phenotypes

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    The use of networks to integrate different genetic, proteomic, and metabolic datasets has been proposed as a viable path toward elucidating the origins of specific diseases. Here we introduce a new phenotypic database summarizing correlations obtained from the disease history of more than 30 million patients in a Phenotypic Disease Network (PDN). We present evidence that the structure of the PDN is relevant to the understanding of illness progression by showing that (1) patients develop diseases close in the network to those they already have; (2) the progression of disease along the links of the network is different for patients of different genders and ethnicities; (3) patients diagnosed with diseases which are more highly connected in the PDN tend to die sooner than those affected by less connected diseases; and (4) diseases that tend to be preceded by others in the PDN tend to be more connected than diseases that precede other illnesses, and are associated with higher degrees of mortality. Our findings show that disease progression can be represented and studied using network methods, offering the potential to enhance our understanding of the origin and evolution of human diseases. The dataset introduced here, released concurrently with this publication, represents the largest relational phenotypic resource publicly available to the research community.Comment: 28 pages (double space), 6 figure

    Evidence for Efimov quantum states in an ultracold gas of cesium atoms

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    Systems of three interacting particles are notorious for their complex physical behavior. A landmark theoretical result in few-body quantum physics is Efimov's prediction of a universal set of bound trimer states appearing for three identical bosons with a resonant two-body interaction. Counterintuitively, these states even exist in the absence of a corresponding two-body bound state. Since the formulation of Efimov's problem in the context of nuclear physics 35 years ago, it has attracted great interest in many areas of physics. However, the observation of Efimov quantum states has remained an elusive goal. Here we report the observation of an Efimov resonance in an ultracold gas of cesium atoms. The resonance occurs in the range of large negative two-body scattering lengths, arising from the coupling of three free atoms to an Efimov trimer. Experimentally, we observe its signature as a giant three-body recombination loss when the strength of the two-body interaction is varied. We also detect a minimum in the recombination loss for positive scattering lengths, indicating destructive interference of decay pathways. Our results confirm central theoretical predictions of Efimov physics and represent a starting point with which to explore the universal properties of resonantly interacting few-body systems. While Feshbach resonances have provided the key to control quantum-mechanical interactions on the two-body level, Efimov resonances connect ultracold matter to the world of few-body quantum phenomena.Comment: 18 pages, 3 figure

    Flying-seed-like mesogens 6: Synthesis and mesomorphism of phthalocyanine derivatives substituted by pentafluorosulfanylphenoxy group

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    We have synthesized two novel phthalocyanines, (m-SF5PhO)(8)PcCu (7b) and (p-SF5PhO)(8)PcCu (7c), in order to investigate their flying-seed-like mesomorphism. Their phase transition behavior and the mesophase structure have been established by using a polarizing optical microscope, a differential scanning calorimeter, and a temperature-dependent small angle X-ray diffractometer. Very interestingly, the derivative (m-SF5PhO)(8)PcCu (7b) substituted a SF 5 group at m-position showed a Col(10)(P2(1)/a) (= p2gg) mesophase from rt to 315.0 degrees C, whereas the derivative (p-SF5PhO)(8)PcCu (7c) substituted a SF 5 group at p-position showed a crystalline (K) phase from rt to the decomposition temperature at ca. 336 degrees C without showing mesomorphism. Thus, the novel phthalocyanine derivative (m-SF5PhO)(8)PcCu (7b) substituted a strong electron withdrawing SF 5 group at m-position shows only one columnar mesophase in a very wide temperature region from rt to 315.0 degrees C. Furthermore, the Q-band wavelengths (672.2 and 672.1 nm) of the present (m-SF5PhO)(8)PcCu (7b) and (p-SF5PhO)(8)PcCu (7c) are shorter than that (680.3 nm) of the previous [(m-C-1) PhO](8)PcCu (5c) derivative. It can be attributed to strong electron withdrawing nature of the SF5 group on the phenoxy group.ArticleJOURNAL OF PORPHYRINS AND PHTHALOCYANINES. 20(7):822-832 (2016)journal articl
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