다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Photoinduced reactivity of titanium dioxide

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

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Climate Change 2007: The Physical Science Basis.

Graphene’s success has shown that it is possible to create stable, single and few-atom-thick layers of van der Waals materials, and also that these materials can exhibit fascinating and technologically useful properties. Here we review the state-of-the-art of 2D materials beyond graphene. Initially, we will outline the different chemical classes of 2D materials and discuss the various strategies to prepare single-layer, few-layer, and multilayer assembly materials in solution, on substrates, and on the wafer scale. Additionally, we present an experimental guide for identifying and characterizing single-layer-thick materials, as well as outlining emerging techniques that yield both local and global information. We describe the differences that occur in the electronic structure between the bulk and the single layer and discuss various methods of tuning their electronic properties by manipulating the surface. Finally, we highlight the properties and advantages of single-, few-, and many-layer 2D materials in...

/pdf/progress-challenges-and-opportunities-in-two-dimensional-1sweg4hljr.pdf

Progress, Challenges, and Opportunities in Two-Dimensional Materials Beyond Graphene

Manipulation of Phase Structure and Se Vacancy to Enhance the Average Thermoelectric Performance of AgBiSe 2

OBJECTIVES
To study the mechanism of retinoic acid receptor α (RARα) signal change to regulate neurexin 1 (NRXN1) in the visual cortex and participate in the autistic-like behavior in rats with vitamin A deficiency (VAD).


METHODS
The models of vitamin A normal (VAN) and VAD pregnant rats were established, and some VAD maternal and offspring rats were given vitamin A supplement (VAS) in the early postnatal period. Behavioral tests were performed on 20 offspring rats in each group at the age of 6 weeks. The three-chamber test and the open-field test were used to observe social behavior and repetitive stereotyped behavior. High-performance liquid chromatography was used to measure the serum level of retinol in the offspring rats in each group. Electrophysiological experiments were used to measure the long-term potentiation (LTP) level of the visual cortex in the offspring rats. Quantitative real-time PCR and Western blot were used to measure the expression levels of RARα, NRXN1, and N-methyl-D-aspartate receptor 1 (NMDAR1). Chromatin co-immunoprecipitation was used to measure the enrichment of RARα transcription factor in the promoter region of the NRXN1 gene.


RESULTS
The offspring rats in the VAD group had autistic-like behaviors such as impaired social interactions and repetitive stereotypical behaviors, and VAS started immediately after birth improved most of the behavioral deficits in offspring rats. The offspring rats in the VAD group had a significantly lower serum level of retinol than those in the VAN and VAS groups (P<0.05). Compared with the offspring rats in the VAN and VAS groups, the offspring rats in the VAD group had significant reductions in the mRNA and protein expression levels of NMDAR1, RARα, and NRXN1 and the LTP level of the visual cortex (P<0.05). The offspring rats in the VAD group had a significant reduction in the enrichment of RARα transcription factor in the promoter region of the NRXN1 gene in the visual cortex compared with those in the VAN and VAS groups (P<0.05).


CONCLUSIONS
RARα affects the synaptic plasticity of the visual cortex in VAD rats by regulating NRXN1, thereby participating in the formation of autistic-like behaviors in VAD rats.

Involvement of retinoic acid receptor α in the autistic-like behavior of rats with vitamin A deficiency by regulating neurexin 1 in the visual cortex: a mechanism study.

This study investigated the effects of nonthermal Ar/O2 plasma on the osseointegration of titanium implants. Through 8 weeks' in vivo evaluation of implants inserted into femoral bones of male Sprague-Dawley rats, the new bone mineralization apposition rate (MAR) is increased by 1.87 and 2.14 times for implants of smooth machined (SM) and sand-blasted and acid-etched (SLA) after plasma treatment. The bone volume fraction (bone volume/total volume, BV/TV) and bone-implant contact (BIC) ratios are improved by 1.31, 1.26 times and 1.35, 1.15 times after 90 s plasma treatment. The improved hydrophilicity rather than implant surface morphology is believed to play a critical role for the osseointegration improvement.

Improvement implant osseointegration through nonthermal Ar/O2 plasma.

Diffraction grating is a fundamental optical element in spectral measurement or source monochromation. A newly designed grating named as two-dimension trapezoidal grating (TG), which not only has non-harmonic diffraction, non-background contaminations, but also has high absolute diffraction efficiency and easy fabrication, was proposed, recently. However, its applications in spectral measurement or source monochromation are limited as its diffraction pattern is more complex than ordinary grating and there is no raytracing simulation tool to effectively analyze and evaluate the property of an optical system with TG. A raytracing model for TG based on the scalar diffraction and scattering theory is proposed to solve the above problem. Diffraction direction and absolute efficiency of each diffraction order are obtained by using mathematical derivation with scattering theory and scalar diffraction theory, respectively, which are the key parts of TG’s raytracing model. Once TG’s raytracing module is added into the optical simulation tool, X-LAB, it offers a new opportunity for design and numerical simulation of optical systems with a TG.Diffraction grating is a fundamental optical element in spectral measurement or source monochromation. A newly designed grating named as two-dimension trapezoidal grating (TG), which not only has non-harmonic diffraction, non-background contaminations, but also has high absolute diffraction efficiency and easy fabrication, was proposed, recently. However, its applications in spectral measurement or source monochromation are limited as its diffraction pattern is more complex than ordinary grating and there is no raytracing simulation tool to effectively analyze and evaluate the property of an optical system with TG. A raytracing model for TG based on the scalar diffraction and scattering theory is proposed to solve the above problem. Diffraction direction and absolute efficiency of each diffraction order are obtained by using mathematical derivation with scattering theory and scalar diffraction theory, respectively, which are the key parts of TG’s raytracing model. Once TG’s raytracing module is added into...

Two-dimension trapezoidal grating raytracing based on the scalar diffraction and scattering theory

Zintl-phase compounds have been extensively studied in recent years due to their phonon-glass and electron-crystal structure. As a ZrBeSi-type Zintl-phase compound, SrCuSb exhibits both high electrical transport properties and thermal conductivity because of the fully occupied anionic framework. In this work, the thermoelectric properties of SrCuSb were refined by Sr self-doping. The increased Sr content not only suppressed the secondary phase SrCu2Sb2 but also lowered the carrier contribution to the thermal conductivity. A zT value of ∼0.36 was achieved for Sr1.05CuSb at 700 K. To further decrease the thermal conductivity, Ba was introduced to the alloy at the Sr site. Benefiting from the point defect scattering, the lattice thermal conductivity was reduced to ∼0.7 W K–1 m–1 at 760 K for the Sr0.75Ba0.3CuSb sample. Finally, a peak zT of ∼0.5 was obtained for Sr0.75Ba0.3CuSb at 773 K. 

Qian Zhang

Papers

Manipulation of Phase Structure and Se Vacancy to Enhance the Average Thermoelectric Performance of AgBiSe 2

Involvement of retinoic acid receptor α in the autistic-like behavior of rats with vitamin A deficiency by regulating neurexin 1 in the visual cortex: a mechanism study.

Improvement implant osseointegration through nonthermal Ar/O2 plasma.

Two-dimension trapezoidal grating raytracing based on the scalar diffraction and scattering theory

Realizing Enhanced Thermoelectric Performance in Zintl-Phase SrCuSb by Reducing the Thermal Conductivity