177 research outputs found
The City-Writing of Jonathan Swift’s A Description of a City Shower
Jonathan Swift’s poems received little attention in the past, which are replete with realism and satire. From the perspective of City-Writing, this article will analyze how Swift logically shuffled the filthy side of London into the sanctuary of poetry by means of satire and realism. Through the minute description of London, Swift gave the readers a sense of surprise and disgust to stimulate them to perform good deeds and to realize their self-redemption
Noncollinearity-modulated electronic properties of the monolayer CrI
Introducing noncollinear magnetization into a monolayer CrI is proposed
to be an effective approach to modulate the local electronic properties of the
two-dimensional (2D) magnetic material. Using first-principles calculation, we
illustrate that both the conduction and valence bands in the monolayer CrI
are lowered down by spin spiral states. The distinct electronic structure of
the monolayer noncollinear CrI can be applied in nanoscale functional
devices. As a proof of concept, we show that a magnetic domain wall can form a
one-dimensional conducting channel in the 2D semiconductor via proper gating.
Other possible applications such as electron-hole separation and identical
quantum dots are also discussed
Cerebral vasomotor reactivity predicts the development of acute stroke in patients with internal carotid artery stenosis
Objective
To investigate the relationship between cerebral vasomotor reactivity (VMR) and acute stroke in patients with internal carotid artery stenosis.
Methods
54 patients with internal carotid artery stenosis were enrolled. VMR was calculated by transcranial Doppler monitoring of the velocity of blood flow. 3-Dimensional dynamic contrast enhanced magnetic resonance angiography was used to detect stenosis, and diffusion weighted imaging was used to detect infarction.
Results
VMR value was significantly lower in patients with carotid artery stenosis than in control group (T=3.112, P=0.002), and significantly lower in patients with aortic atherosclerotic stroke than in non-infarct group (T=10.930, P=0.000). However, VMR value was significantly higher in patients with new-onset small-artery occlusion stroke than in non-infarction group (T=−2.538, P=0.013). Scatter plots showed that aortic atherosclerotic stroke occurred mainly in patients with severe internal carotid artery stenosis, and VMR value in cerebral artery significantly decreased.
Conclusion
Decreased VMR value is an important prognostic factor for the occurrence of aortic atherosclerotic stroke, and can be used as a reference for preoperative hemodynamic evaluation in patients with internal carotid artery stenosis
Improving "color rendering" of LED lighting for the growth of lettuce
Light plays a vital role on the growth and development of plant. On the base of white light with high color rendering to the benefit of human survival and life, we proposed to improve “color rendering” of LED lighting for accelerating the growth of lettuce. Seven spectral LED lights were adopted to irradiate the lettuces under 150 μmol·m−2·s−1 for a 16 hd−1 photoperiod. The leaf area and number profiles, plant biomass, and photosynthetic rate under the as-prepared LED light treatments were investigated. We let the absorption spectrum of fresh leaf be the emission spectrum of ideal light and then evaluate the “color rendering” of as-prepared LED lights by the Pearson product-moment correlation coefficient and CIE chromaticity coordinates. Under the irradiation of red-yellow-blue light with high correlation coefficient of 0.587, the dry weights and leaf growth rate are 2-3 times as high as the sharp red-blue light. The optimized LED light for lettuce growth can be presumed to be limited to the angle (about 75°) between the vectors passed through the ideal light in the CIE chromaticity coordinates. These findings open up a new idea to assess and find the optimized LED light for plant growth
Pressure induced superconductivity in WB2 and ReB2 through modifying the B layers
The recent discovery of superconductivity up to 32 K in the pressurized MoB2
reignites the interests in exploring high-Tc superconductors in
transition-metal diborides. Inspired by that work, we turn our attention to the
5d transition-metal diborides. Here we systematically investigate the responses
of both structural and physical properties of WB2 and ReB2 to external
pressure, which possess different types of boron layers. Similar to MoB2, the
pressure-induced superconductivity was also observed in WB2 above 60 GPa with a
maximum Tc of 15 K at 100 GPa, while no superconductivity was detected in ReB2
in this pressure range. Interestingly, the structures at ambient pressure for
both WB2 and ReB2 persist to high pressure without structural phase
transitions. Theoretical calculations suggest that the ratio of flat boron
layers in this class of transition-metal diborides may be crucial for the
appearance of high Tc. The combined theoretical and experimental results
highlight the effect of geometry of boron layers on superconductivity and shed
light on the exploration of novel high-Tc superconductors in borides.Comment: 17 pages,5 figure
A novel liposomal S-propargyl-cysteine: a sustained release of hydrogen sulfide reducing myocardial fibrosis via TGF-β1/Smad pathway
Purpose: S-propargyl-cysteine (SPRC; alternatively known as ZYZ-802) is a novel modulator of endogenous tissue H2S concentrations with known cardioprotective and anti-inflammatory effects. However, its rapid metabolism and excretion have limited its clinical application. To overcome these issues, we have developed some novel liposomal carriers to deliver ZYZ-802 to cells and tissues and have characterized their physicochemical, morphological and pharmacological properties. Methods :Two liposomal formulations of ZYZ-802 were prepared by thin-layer hydration and the morphological characteristics of each liposome system were assessed using a laser particle size analyzer and transmission electron microscopy. The entrapment efficiency and ZYZ-802 release profiles were determined following ultrafiltration centrifugation, dialysis tube and HPLC measurements. LC-MS/MS was used to evaluate the pharmacokinetic parameters and tissue distribution profiles of each formulation via the measurements of plasma and tissues ZYZ-802 and H2S concentrations. Using an in vivo model of heart failure (HF), the cardio-protective effects of liposomal carrier were determined by echocardiography, histopathology, western blot and the assessment of antioxidant and myocardial fibrosis markers.Results: Both liposomal formulations improved ZYZ-802 pharmacokinetics and optimized H2S concentrations in plasma and tissues. Liposomal ZYZ-802 showed enhanced cardioprotective effects in vivo. Importantly, liposomal ZYZ-802 could inhibit myocardial fibrosis via the inhibition of the TGF-β1/Smad signaling pathway. Conclusion: The liposomal formulations of ZYZ-802 have enhanced pharmacokinetic and pharmacological properties in vivo. This work is the first report to describe the development of liposomal formulations to improve the sustained release of H2S within tissues.Key word: Liposome; S-Propargyl-cysteine (SPRC, ZYZ-802); Hydrogen sulfide; Heart failure; Myocardial fibrosis; TGF-β1/Smad pathwa
Spectral broadening of a single Ce3+-doped garnet by chemical unit cosubstitution for near ultraviolet LED
In this paper, the isostructural Mg3Al2Si3O12 was introduced into the Ce3+-doped yttrium aluminum garnet (Y3Al5O12) for synthesizing (Y1-xMgx)3Al2(Al1-xSix)3O12:Ce3+ (x = 0-0.6) solid solution phosphors. The co-substitution of the (Mg, Si)6+ pair for the (Y, Al)6+ pair leads to lattice shrinkage and then changes the spectral shape and width. The band peaking at ~450 nm shows a substantial broadening with the full width at half maximum increasing from 65 nm to 94 nm. The intensity of excitation spectrum (x = 0.5) at 400 nm is increased by 50% than that (x = 0). The near ultraviolet LED was fabricated with Y1.5Mg1.5Al3.5Si1.5O12:Ce3+ phosphors and a 400 nm chip and can emit strong white light. Therefore, by controlling the content of (Y, Al)6+ substituted by (Mg, Si)6+, the excitation spectrum of Ce3+-doped Y3Al5O12 can be tuned and applied for the near ultraviolet LEDs
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