1,334 research outputs found
Phase Reversal Diffraction in incoherent light
Phase reversal occurs in the propagation of an electromagnetic wave in a
negatively refracting medium or a phase-conjugate interface. Here we report the
experimental observation of phase reversal diffraction without the above
devices. Our experimental results and theoretical analysis demonstrate that
phase reversal diffraction can be formed through the first-order field
correlation of chaotic light. The experimental realization is similar to phase
reversal behavior in negatively refracting media.Comment: 8 pages, 5 figure
Phenylboronic acid-diol crosslinked 6-<i>O</i>-vinylazeloyl-d-galactose nanocarriers for insulin delivery
A new block polymer named poly 3-acrylamidophenylboronic acid-b-6-O–vinylazeloyl-d-galactose (p(AAPBA-b-OVZG)) was prepared using 3-acrylamidophenylboronic acid (AAPBA) and 6-O-vinylazeloyl-D-galactose (OVZG) via a two-step procedure involving S-1-dodecyl-S-(α', α'-dimethyl-α″-acetic acid) trithiocarbonate (DDATC) as chain transfer agent, 2,2-azobisisobutyronitrile (AIBN) as initiator and dimethyl formamide (DMF) as solvent. The structures of the polymer were examined by Fourier transform infrared spectroscopy (FT-IR) and 1H NMR and the thermal stability was determined by thermal gravimetric analysis (TG/DTG). Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were utilized to evaluate the morphology and properties of the p(AAPBA-b-OVZG) nanoparticles. The cell toxicity, animal toxicity and therapeutic efficacy were also investigated. The results indicate the p(AAPBA-b-OVZG) was successfully synthesized and had excellent thermal stability. Moreover, the p(AAPBA-b-OVZG) nanoparticles were submicron in size and glucose-sensitive in phosphate-buffered saline (PBS). In addition, insulin as a model drug had a high encapsulation efficiency and loading capacity and the release of insulin was increased at higher glucose levels. Furthermore, the nanoparticles showed a low-toxicity in cell and animal studies and they were effective at decreasing blood glucose levels of mice over 96 h. These p(AAPBA-b-OVZG) nanoparticles show promise for applications in diabetes treatment using insulin or other hypoglycemic proteins
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Phase Control on Surface for the Stabilization of High Energy Cathode Materials of Lithium Ion Batteries.
The development of high energy electrode materials for lithium ion batteries is challenged by their inherent instabilities, which become more aggravated as the energy densities continue to climb, accordingly causing increasing concerns on battery safety and reliability. Here, taking the high voltage cathode of LiNi0.5Mn1.5O4 as an example, we demonstrate a protocol to stabilize this cathode through a systematic phase modulating on its particle surface. We are able to transfer the spinel surface into a 30 nm shell composed of two functional phases including a rock-salt one and a layered one. The former is electrochemically inert for surface stabilization while the latter is designated to provide necessary electrochemical activity. The precise synthesis control enables us to tune the ratio of these two phases, and achieve an optimized balance between improved stability against structural degradation without sacrificing its capacity. This study highlights the critical importance of well-tailored surface phase property for the cathode stabilization of high energy lithium ion batteries
A Heterogeneous Multiattribute Group Decision-Making Method Based on Intuitionistic Triangular Fuzzy Information
The chloride channel cystic fibrosis transmembrane conductance regulator (CFTR) controls cellular quiescence by hyperpolarizing the cell membrane during diapause in the crustacean Artemia
Cellular quiescence, a reversible state in which growth, proliferation, and other cellular activities are arrested, is important for self-renewal, differentiation, development, regeneration, and stress resistance. However, the physiological mechanisms underlying cellular quiescence remain largely unknown. In the present study, we used embryos of the crustacean Artemia in the diapause stage, in which these embryos remain quiescent for prolonged periods, as a model to explore the relationship between cell-membrane potential (V-mem) and quiescence. We found that V-mem is hyperpolarized and that the intracellular chloride concentration is high in diapause embryos, whereas V-mem is depolarized and intracellular chloride concentration is reduced in postdiapause embryos and during further embryonic development. We identified and characterized the chloride ion channel protein cystic fibrosis transmembrane conductance regulator (CFTR) of Artemia (Ar-CFTR) and found that its expression is silenced in quiescent cells of Artemia diapause embryos but remains constant in all other embryonic stages. Ar-CFTR knockdown and GlyH-101-mediated chemical inhibition of Ar-CFTR produced diapause embryos having a high V-mem and intracellular chloride concentration, whereas control Artemia embryos released free-swimming nauplius larvae. Transcriptome analysis of embryos at different developmental stages revealed that proliferation, differentiation, and metabolism are suppressed in diapause embryos and restored in postdiapause embryos. Combined with RNA sequencing (RNA-Seq) of GlyH-101-treated MCF-7 breast cancer cells, these analyses revealed that CFTR inhibition down-regulates the Wnt and Aurora Kinase A (AURKA) signaling pathways and up-regulates the p53 signaling pathway. Our findings provide insight into CFTR-mediated regulation of cellular quiescence and V-mem in the Artemia model
Topological superconductor to Anderson localization transition in one-dimensional incommensurate lattices
We study the competition of disorder and superconductivity for a
one-dimensional p-wave superconductor in incommensurate potentials. With the
increase in the strength of the incommensurate potential, the system undergoes
a transition from a topological superconducting phase to a topologically
trivial localized phase. The phase boundary is determined both numerically and
analytically from various aspects and the topological superconducting phase is
characterized by the presence of Majorana edge fermions in the system with open
boundary conditions. We also calculate the topological invariant of the
bulk system and find it can be used to distinguish the different topological
phases even for a disordered system.Comment: 5 + 4 pages, 5 +2 figures, version appeared in PRL, supplementary
material include
Dependence of Spiral Galaxy Distribution on Viewing Angle in RC3
The normalized inclination distributions are presented for the spiral
galaxies in RC3. The results show that, except for the bin of
-, in which the apparent minor isophotal diameters that
are used to obtain the inclinations, are affected by the central bulges, the
distributions for Sa, Sab, Scd and Sd are well consistent with the Monte-Carlo
simulation of random inclinations within 3-, and Sb and Sbc almost, but
Sc is different. One reason for the difference between the real distribution
and the Monte-Carlo simulation of Sc may be that some quite inclined spirals,
the arms of which are inherently loosely wound on the galactic plane and should
be classified to Sc galaxies, have been incorrectly classified to the earlier
ones, because the tightness of spiral arms which is one of the criteria of the
Hubble classification in RC3 is different between on the galactic plane and on
the tangent plane of the celestial sphere. Our result also implies that there
might exist biases in the luminosity functions of individual Hubble types if
spiral galaxies are only classified visually.Comment: 5 pages + 8 figures, LaTe
The Effect of Cluster Position Determined by Vineyard Row Orientation on Grape Flavonoids and Aroma Profiles of Vitis vinifera L. cv. Cabernet Sauvignon and Italian Riesling in the North Foot of Tianshan Mountains
Vineyard row orientation plays a critical role in determining cluster microclimate. This study aimed tofigure out how cluster positions determined by vineyard row orientation affect grape flavonoids and aromaprofiles of Cabernet Sauvignon and Italian Riesling grapes. Three cluster positions (two canopy sidesand the inner canopy) of NS and EW oriented row Cabernet Sauvignon and NS oriented row ItalianRiesling were selected for the experiment. Microclimate data was monitored around clusters from bothcanopy sides of different row orientations. The south canopy side had higher daytime temperaturesand PAR than the north canopy side in EW row orientation. Flavonoids of grape skins and seeds wereseparated and determined by LC-MS, and aroma compounds of grape must were determined by GC-MS.Results showed that flavanols were affected by orientations, and EW orientation had higher berries skinflavanol concentration than NS orientation. EW-IN berries had fewer glucuronide form flavonols and3’-hydroxylated flavonols than the other two positions in EW orientation. Inner canopy berries had lowerflavonol concentration than other positions in EW orientation of CS and NS orientation of IR. To aromas,C6/C9 were the main compounds significantly affected by row orientations. EW orientation berries hadhigher C6 alcohols concentration such as (E)-3-Hexen-1-ol, (E)-2-Hexen-1-ol and (Z)-3-Hexen-1-ol thanNS orientation, while NS orientation berries had higher C6 aldehyde concentrations such as Hexanal and(E)-2-hexenal than EW orientation. EW-IN berries had more abundant C6/C9 compounds than the othertwo positions. The study provided preliminary scientific evidence for vineyard viticulture practice andharvest strategy
Clinical research on liver reserve function by 13C-phenylalanine breath test in aged patients with chronic liver diseases
<p>Abstract</p> <p>Background</p> <p>The objective of this study was to investigate whether the <sup>13</sup>C-phenylalanine breath test could be useful for the evaluation of hepatic function in elderly volunteers and patients with chronic hepatitis B and liver cirrhosis.</p> <p>Methods</p> <p>L-[1-<sup>13</sup>C] phenylalanine was administered orally at a dose of 100 mg to 55 elderly patients with liver cirrhosis, 30 patients with chronic hepatitis B and 38 elderly healthy subjects. The breath test was performed at 8 different time points (0, 10, 20, 30, 45, 60, 90, 120 min) to obtain the values of Delta over baseline, percentage <sup>13</sup>CO<sub>2 </sub>exhalation rate and cumulative excretion (Cum). The relationships of the cumulative excretion with the <sup>13</sup>C-%dose/h and blood biochemical parameters were investigated.</p> <p>Results</p> <p>The <sup>13</sup>C-%dose/h at 20 min and 30 min combined with the cumulative excretion at 60 min and 120 min correlated with hepatic function tests, serum albumin, hemoglobin, platelet and Child-Pugh score. Prothrombin time, total and direct bilirubin were significantly increased, while serum albumin, hemoglobin and platelet, the cumulative excretion at 60 min and 120 min values decreased by degrees of intensity of the disease in Child-Pugh A, B, and C patients (P < 0.01).</p> <p>Conclusions</p> <p>The <sup>13</sup>C-phenylalanine breath test can be used as a non-invasive assay to evaluate hepatic function in elderly patients with liver cirrhosis. The <sup>13</sup>C-%dose/h at 20 min, at 30 min and cumulative excretion at 60 min may be the key value for determination at a single time-point. <sup>13</sup>C-phenylalanine breath test is safe and helpful in distinguishing different stages of hepatic dysfunction for elderly cirrhosis patients.</p
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