Valley depolarization in monolayer WSe2

We have systematically examined the circular polarization of monolayer WSe2 at different temperature, excitation energy and exciton density. The valley depolarization in WSe2 is experimentally confirmed to be governed by the intervalley electron-hole exchange interaction. More importantly, a non-monotonic dependence of valley circular polarization on the excitation power density has been observed, providing the experimental evidence for the non-monotonic dependence of exciton intervalley scattering rate on the excited exciton density. The physical origination of our experimental observations has been proposed, which is in analogy to the D'yakonov-Perel' mechanism that is operative in conventional GaAs quantum well systems. Our experimental results are fundamentally important for well understanding the valley psudospin relaxation in atomically thin transition metal dichalcogenides

Effects of anesthesia on conventional and speckle tracking echocardiographic parameters in a mouse model of pressure overload

Genetically‑modified mice are widely applied in cardiovascular studies as model organisms. Echocardiography is a key tool for evaluating cardiac and hemodynamic functions in mice. The present study aimed to examine the effects of isoflurane (ISF) on conventional and speckle tracking echocardiography (STE) parameters under healthy and pathological conditions using a murine model of pressure overload. In addition, the optimal dose of ISF in the process of echocardiographic measurement, with minimum cardiac contraction depression, was investigated. Conventional echocardiographic and STE examinations were performed on 38 adult C57BL/6 male mice. The mice were divided into the following three groups: The sham (n=15); mild thoracic aortic banding (TAB; n=15); and severe TAB (n=8) groups. ISF was administered under deep anesthesia (DA; 1‑2% ISF), light anesthesia (LA; 0.5‑1% ISF) and immediately prior to the mice waking up (awake; 0‑0.5% ISF). Conventional echocardiographic parameters were preserved within the sham and mild TAB groups (P>0.05 for each parameter) under LA and awake conditions. However, under DA conditions, the majority of these parameters were reduced compared with the LA and awake conditions (P<0.05). In the severe TAB group, conventional echocardiographic parameters remained constant under LA, DA and awake conditions. STE parameters in the groups remained similar between the LA and awake conditions, but were significantly reduced under DA conditions. Therefore, conventional echocardiography and STE may be performed using LA induced with low doses of ISF, under various pathological conditions without affecting cardiac function

5-(4-Methyl­phen­yl)-2,3-diphenyl-5,6-dihydro­imidazo[1,2-c]quinazoline

In the title compound, C29H23N3, the pyrimidine ring adopts an envelope conformation. The dihedral angle between the phenyl rings attached to the pyrimidine-ring double bond is 62.09 (7)°. In the crystal, mol­ecules are linked by N—H⋯N hydrogen bonds, forming extended chains in the c-axis directio

2-(4-Methyl­phen­yl)-2H-indazole

The title compound, C14H12N2, was synthesized by the reaction of 4-methyl-N-(2-nitro­benz­yl)aniline with tin(II) chloride dihydrate in ethanol at 313 K. The indazole ring system is almost planar with a dihedral angle of 1.58 (10)° between the rings, whereas the plane of the attached p-tolyl substituent shows a dihedral angle of 46.26 (5)° with respect to the indazole core