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Diguo Zhai,1,2 Qingwei Chen,1,2 Ying Yao,3 Taotao Ru,1,2 Guofu Zhou1,2 1Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, 510006, People’s Republic of China; 2National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou, 510006, People’s Republic of China; 3Anhui Provincial Library, Hefei, 230000, People’s Republic of ChinaCorrespondence: Taotao Ru; Qingwei Chen, Lab of Light and Physio-Psychological Health-National Center for International Research on Green Optoelectronics-South China Academy of Advanced Optoelectronics-South China Normal University, No. 55, West Zhongshan Road, Tianhe District, Guangzhou, 510631, People’s Republic of China, Tel +86 15603063417 ; +86 15521094813, Email taotao.ru@m.scnu.edu.cn; qingwei.chen@m.scnu.edu.cnPurpose: To explore whether sleep electroencephalogram (EEG) microarousals of different standard durations predict daytime mood and attention performance in healthy individuals after mild sleep restriction.Participants and Methods: Sixteen (nine female) healthy college students were recruited to examine the correlations between nocturnal EEG microarousals of different standard durations (≥ 3 s, ≥ 5 s, ≥ 7 s, ≥ 9 s) under mild sleep restriction (1.5 h) and the following morning’s subjective alertness, mood, sustained attention, and selective attention task performance.Results: Results revealed that mild sleep restriction significantly reduced subjective alertness and positive mood, while having no significant effect on negative mood, sustained attention and selective attention performance. The number of microarousals (≥ 5 s) was negatively associated with positive mood at 6:30. The number of microarousals was significantly and positively correlated with the response time difference value of disengagement component of the selective attention task at around 7:30 (≥ 5 s and ≥ 7 s) and 9:00 (≥ 5 s). The number of microarousals (≥ 7 s) was significantly and positively correlated with the inaccuracy difference value of orientation component of the selective attention task at around 9:00.Conclusion: The number of EEG microarousals during sleep in healthy adults with mild sleep restriction was significantly and negatively related to their daytime positive affect while positively associated with the deterioration of disengagement and orientation of selective attention performance, but this link is dependent on the standard duration of microarousals, test time and the type of task.Keywords: microarousal, alertness, sustained attention, selective attention, sleep restriction

A new algorithm for cylindrical Bessel functions that is similar to the one for spherical Bessel functions allows us to compute scattering functions for infinitely long cylinders covering sizes ka = 2 [Pi]a/[Lambda] up to 8000 through the use of only an eight-digit single-precision machine computation. The scattering function and complex extinction coefficient of a finite cylinder that is seen near perpendicular incidence are derived from those of an infinitely long cylinder by the use of Huygens's principle. The result, which contains no arbitrary normalization factor, agrees quite well with analog microwave measurements of both extinction and scattering for such cylinders, even for an aspect ratio p = l/(2a) as low as 2. Rainbows produced by cylinders are similar to those for spherical drops but are brighter and have a lower contrast.

The current–voltage (I–V) characteristics of CrNiCo alloy Schottky contacts on a molecular-beam epitaxy n-GaAs substrate have been measured over the temperature range of 130–330 K and have been interpreted based on the assumption of a Gaussian distribution of barrier heights due to barrier height inhomogeneities that prevail at the interface. It is shown that the occurrence of Gaussian distribution of then barrier heights is responsible for the decrease of the apparent barrier height &Fgr;[sub b0], increase of the ideality factor n and nonlinearity in the activation energy plot at low temperatures. A &Fgr;[sub b0] vs 1/T plot was drawn to obtain evidence of a Gaussian distribution of the barrier heights, and values of &Fgr;¯[sub b0](T=0)=1.02 eV and σ[sub 0]=0.105 V for the mean barrier height and zero-bias standard deviation, respectively, have been obtained from this plot. Thus, a modified ln(I[sub 0]/T[sup 2])-q[sup 2]σ[sub 0][sup 2]/2k[sup 2]T[sup 2] vs 1/T plot gives &Fgr;¯[sub b0](T=0) and A[sup *] as 1.02 eV and 5.13 A/cm2 K2, respectively, without using the temperature coefficient of the barrier height. It has been concluded that the temperature dependent I–V characteristics of the device can be successfully explained on the basis of a thermionic emission mechanism with Gaussian distribution of the barrier heights. Furthermore, a value of -0.305 meV/K for the temperature coefficient of the flat band barrier height has been obtained; this value for n-GaAs is in very close agreement with values in the literature. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the synchrony effect between chronotype and time of day on task switching and vigilance, and the effect of high illuminance on the performance of two chronotypes at their non-optimal time. Four 46 minute sessions were administrated on separate days, the illuminance (200 vs. 1200 lx at eye level) and time of day (1.5 hours vs. 10.5 hours after waking up) were manipulated within participants. We found that high illuminance (1200 lx) significantly decreased the latency switch cost only for evening type independent of time of day, and there was a trend that low illuminance (200 lx) was better for morning type to decrease latency switch cost compared with evening type. The high illuminance could decrease the subjective sleepiness significantly for both chronotypes at the later part of the experiment. No synchrony effect on task switching and vigilance was found in the present study. The results suggested that the effect of ambient light on task switching was modulated by chronotype. Current study enriched the research on the effect of ambient light on task switching. When setting the optimal light environment, we should considerate the individual difference such as chronotype. [ABSTRACT FROM AUTHOR]

In low-dimensional electronic materials, the charge or spin ordering can be subtly controlled by specific mode or modes, giving rise to functioning states such as charge- and spin-density waves, Mott insulators, and superconductors. The coupling between the electrons and the atomic lattice can be effectively investigated by ultrafast optical, photoemission, and electron diffraction techniques providing detailed description of microscopic and collective state evolutions in separate electronic and lattice subsystems. However, the electronic and phononic relaxation time scales obtained from these techniques are often distinctly different in low-dimensional electronic materials, even in a system as simple as graphite. Here, we seek to understand their origins from examining the nonequilibrium scenarios considering anisotropic electron-phonon coupling leading to hot phonons, which can be investigated directly from the momentum-dependent scattering changes in the transmission ultrafast electron crystallography. A three-temperature model is constructed to achieve unified understandings combining ultrafast spectroscopy and diffraction results of the nonadiabatic optically driven dynamics in graphite, charge-density waves in CeTe3, and the Mott insulator VO2. [ABSTRACT FROM AUTHOR]

Using optical, TEM, and ultrafast electron diffraction experiments we find that single crystal V02 microbeams gently placed on insulating substrates or metal grids exhibit different behaviors, with structural and metal-insulator transitions occurring at the same temperature for insulating substrates, while for metal substrates a new monoclinic metal phase lies between the insulating monoclinic phase and the metallic rutile phase. The structural and electronic phase transitions in these experiments are strongly first order and we discuss their origins in the context of current understanding of multiorbital splitting, strong correlation effects, and structural distortions that act cooperatively in this system. [ABSTRACT FROM AUTHOR]

The existence and importance of patients with low penile buckling pressure and normal penile hemodynamic status have been recently recognized. We assessed the ratio of inadequate erection for vaginal penetration (low buckling pressure) in patients with normal penile vascular system proved with penile Doppler ultrasonography. A total of 101 patients with normal penile vascular status were retrospectively scrutinized dependent on penile axial rigidity (buckling pressure). Ninety patients had sufficient penile axial rigidity (≥ 550 g) whereas in the remaining 11 patients (11%) inadequate penile buckling pressure for vaginal penetration (<550 g) was determined. Penile geometric and mechanical properties should not be overlooked during the evaluation of penile vascular system lest the patient be incorrectly diagnosed as having psychogenic impotence. [ABSTRACT FROM AUTHOR]