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About 766 $\delta$ Scuti stars were observed by LAMOST by June 16, 2017. Stellar atmospheric parameters of 525 variables were determined, while spectral types were obtained for all samples. In the paper, those spectroscopic data are catalogued. We detect a group of 131 unusual and cool variable stars (UCVs) that are distinguished from the normal $\delta$ Scuti stars (NDSTs). On the H-R diagram and the $\log g-T$ diagram, the UCVs are far beyond the red edge of pulsational instability trip. Their effective temperatures are lower than 6700\,K with periods in the range from 0.09 to 0.22\,days. NDSTs have metallicity close to that of the Sun as expected, while UCVs are slightly metal poor than NDSTs. The two peaks on the distributions of the period and stellar atmospheric parameters are all caused by the existence of UCVs. When those UCVs are excluded, it is discovered that the effective temperature, the gravitational acceleration and the metallicity all are correlated with the pulsating period for NDSTs and their physical properties and evolutionary states are discussed. The detecting of those UCVs indicates that about 25\% of the known $\delta$ Scuti stars may be misclassified. However, if some of them are confirmed to be pulsating stars, they will be a new-type pulsator and their investigations will shed light on theoretical instability domains and on the theories of interacting between the pulsation and the convection of solar-type stars. Meanwhile, 88 $\delta$ Scuti stars are detected to be the candidates of binary or multiple systems., Comment: 15 pages, 16 figures, accepted for publication in MNRAS

A number of papers deals with the heat conductivity of composite materials: Zarubin et al used new approaches to the problem of evaluation of the effective heat conductivity coefficients of composite material with ball inclusions. We used variational analysis for a simplified model in a vicinity of inclusion. Contemporary computers allow implementing another approach to solving the problem of the effective heat conductivity: it may be modelled by the Brownian motion of virtual heat particles. The main idea is to obtain the exact formula for the heat conductivity for a homogeneous material and subsequently obtain a statistical evaluation of this formula for a composite material.In the present paper we compare two methods for finding the effective heat conductivity coefficients of composite materials by modeling the process of heat conduction via the Brownian motion of virtual heat particles. We consider a composite with ball inclusions of a material with heat conductivity and heat capacity coefficientsdiffering from those of the matrix material. In a computational experiment, we simulate the process of heatconduction through a flat layer of the composite material, which has been heated on one side at the initial moment. In order to find the confidence interval for the effective heat conductivity coefficient, we find, by means of statistics, either the displacement of the center of heat energy, or the probability of a virtual particle to pass through the layer during a certain time. We compare our results with theoretical assessments suggested by other authors.

There are mass data that contain important defect texts in the power grid enterprise, and they contain important reliability information. And the efficiency is very low to mine the exact information about the texts especially when the texts are in Chinese. Thus, the defect text mining technique based on the modified semantic framework is proposed. All texts are translated into English and use the text mining model based on the modified semantic framework, the defect texts are divided into a fixed pattern and the digital information can be extracted accurately. Take the transformer as an example, the first step is to establish the ontology dictionary and to separate the sentence and extract the texts’ features. Then, the modified power semantic framework and the semantic slots are defined, and the slots filling method and the semantic framework construction process are discussed, which can automatically perfect the ontology dictionary by merging the word series. Finally, the researches of defect text mining results of statistical reliability are studied, and the results show that the proposed model and method is feasible and effective when applied to automatic classification and statistics of grid defect.

The first complete VRcIc light curves of V608 Cas are presented and analyzed by using the 2010 version of the W-D code. The photometric results show that V608 Cas is a moderate mass-ratio (q = 0.373 +/- 0.005), shallow contact (f = 19.7 +/- 4.9%) binary. A cool spot is present on the massive component. The orbital period of V608 Cas may increase continuously according to the (0 - C) diagram, with a rate of dP/dt = +6.49 x 10(-7) days/year. The fundamental parameters of V608 Cas are estimated as: M-1 = 0.95 +/- 0.15M(circle dot), M-2 = 035 +/- 0.08M(circle dot), R-1 = 0.78 +/- 0.12R(circle dot), R-2 = 0.50 +/- 0.10R(circle dot), L-1 = 0.563 +/- 0.112L(circle dot), L-2 = 0.233 +/- 0.086L(circle dot), where the uncertainties mainly come from the uncertainty of the primary's effective temperature. (C) 2015 Elsevier B.V. All rights reserved.

Due to the lack of an accretion disk in a polar (magnetic cataclysmic variable, MCV), the material transferred from the secondary is directly accreted onto the white dwarf, forming an accretion stream and a hot spot on the white-dwarf component. During the eclipses, dierent light components can be isolated. Therefore, the monitoring of eclipsing polars could provide valuable information on several modern astrophysical problems, e.g., CVs as planetary hosting stars, mass transfer and mass accretion in CVs, and the magnetic activity of the most rapidly rotating cool dwarfs. In the past ve years, we have monitored about 10 eclipsing polars (e.g., DP Leo and HU Aqr) using several 2-m class telescopes and about 100 eclipse proles were obtained. In this paper, we will introduce the progress of our research group at YNOs. The rst direct evidence of variable mass transfer in a CV is obtained and we show that it is the dark-spot activity that causes the mass transfer in CVs. Magnetic activity cycles of the cool secondary were detected and we show that the variable mass transfer is not caused by magnetic activity cycles. These results will shed light on the structure and evolution of close binary stars (e.g., CVs and Algols).

1SWASP\,J162117.36$+$441254.2 was originally classified as an EW-type binary with a period of 0.20785\,days. However, it was detected to have undergone a stellar outburst on June 3, 2016. Although the system was latter classified as a cataclysmic variable (CV) and the event was attributed as a dwarf-nova outburst, the physical reason is still unknown. This binary has been monitored photometrically since April 19, 2016 and many light curves were obtained before, during and after the outburst. Those light and color curves observed before the outburst indicate that the system is a special CV. The white dwarf is not accreting material from the secondary and there are no accretion disks surrounding the white dwarf. By comparing the light curves obtained from April 19 to September 14, 2016, it was found that magnetic activity of the secondary is associated with the outburst. We show strong evidence that the $L_1$ region on the secondary was heavily spotted before and after the outburst and thus quench the mass transfer, while the outburst is produced by a sudden mass accretion of the white dwarf. These results suggest that J162117 is a good astrophysical laboratory to study stellar magnetic activity and its influences on CV mass transfer and mass accretion., 16 pages, 6 figures, accepted for publication in ApJ

We present CCD light curves of V710 Mon obtained in 2007 and 2013. By using the 2010 version of the W-D code, it is found that the star is a deep (59.5-62.7%) contact binary system, with an extreme mass ratio (0.143-0.183). The period of the system increases with a rate dP/dt = +1.95( +/- 0.06) x 10(-7) days/year. We propose that the system contains a post-main-sequence component which may be in an expanding phase. The time scale of the orbital increase nearly equals to the time for the post-main-sequence star to evolve into a subgiant. The age of the primary is estimated to be 5.34 Gyr. (c) 2014 Published by Elsevier B.V.

As the post-processing method of equipment and tubes is seldom used in the field of super-critical water (SCW), as well as the high cost and low heat transfer performance of some of the materials, more up-to-date methods were developed to inhibit oxidation of SCW. In this work, the ternary Ni-W-P coating was deposited on the sample surface. Structure and composition of ternary Ni-W-P coating were profoundly analyzed with scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and X-ray diffraction (XRD). Additionally, thermal conductivity meter was specially employed to study the performance of heat transfer behaviour, by means of heat-resistance method. After oxidation of SCW, amorphous Ni-W-P coating crystallizes to some extent and oxidation resistance of coating can be convincing. Nevertheless, the diffusion of metal cations and the growth of oxides are the vital factors inhibiting the oxidation of SCW. Furthermore, the thermal conductivity of ternary Ni-W-P coating decreases with the increase of tungsten content and the coating unquestionably shows better heat transfer performance in the field of nuclear waste disposal and transport.

We present the photometric results of the eclipsing cataclysmic variable (CV) WZ Sge near the period minimum ($P_{min}$). Eight new mid-eclipse times were determined and the orbital ephemeris was updated. Our result shows that the orbital period of WZ Sge is decreasing at a rate of $\dot{P}=-2.72(\pm0.23)\times{10^{-13}}\,s s^{-1}$. This secular decrease, coupled with previous detection of its donor, suggest that WZ Sge is a pre-bounce system. Further analysis indicates that the observed period decrease rate is about $1.53$ times higher than pure gravitational radiation (GR) driving. We constructed the evolutionary track of WZ Sge, which predicts that $P_{min}$ of WZ Sge is $\sim77.98 (\pm0.90)$ min. If the orbital period decreases at the current rate, WZ Sge will evolve past its $P_{min}$ after $\sim25.3$ Myr. Based on the period evolution equation we find $\dot{M}_{2}\simeq4.04(\pm0.10)\times10^{-11}M_{\odot}yr^{-1}$, which is compatible with the current concept of CV evolution at ultrashort orbital periods., Comment: 8 pages, 5 figures

DV UMa is an eclipsing dwarf nova with an orbital period of $\sim2.06$ h, which lies just at the bottom edge of the period gap. To detect its orbital period changes we present 12 new mid-eclipse times by using our CCD photometric data and archival data. Combining with the published mid-eclipse times in quiescence, spanning $\sim30$ yr, the latest version of the $O-C$ diagram was obtained and analyzed. The best fit to those available eclipse timings shows that the orbital period of DV UMa is undergoing a cyclic oscillation with a period of $17.58(\pm0.52)$ yr and an amplitude of $71.1(\pm6.7)$ s. The periodic variation most likely arises from the light-travel-time effect via the presence of a circumbinary object because the required energy to drive the Applegate mechanism is too high in this system. The mass of the unseen companion was derived as $M_{3}\sin{i'}=0.025(\pm0.004)M_{\odot}$. If the third body is in the orbital plane (i.e. $i'=i=82.9^{\circ}$) of the eclipsing pair, it would match to a brown dwarf. This hypothetical brown dwarf is orbiting its host star at a separation of $\sim8.6$ AU in an eccentric orbit ($e=0.44$)., Comment: 16 pages, 6 figures

We present a timing analysis of the eclipsing post-common envelope binary (PCEB) DE CVn. Based on new CCD photometric observations and the published data, we found that the orbital period in DE CVn has a cyclic period oscillation with an amplitude of $28.08$ s and a period of $11.22$ years plus a rapid period decrease at a rate of $\dot{P}=-3.35\times10^{-11}ss^{-1}$. According to the evolutionary theory, secular period decreases in PCEBs arise from angular momentum losses (AMLs) driven by gravitational radiation (GR) and magnetic braking (MB). However, the observed orbital decay is too fast to be produced by AMLs via GR and MB, indicating that there could be other AML mechanism. We suggest that a circumbinary disk around DE CVn may be responsible for the additional AML. The disk mass was derived as a few$\times$$10^{-4}$-$10^{-3}$$M_{\odot}$ , which is in agreement with that inferred from previous studies in the order of magnitude. The cyclic change is most likely result of the gravitational perturbation by a circumbinary object due to the Applegate's mechanism fails to explain such a large period oscillation. The mass of the potential third body is calculated as $M_{3}\sin{i'}=0.011(\pm0.003)M_{\odot}$. Supposing the circumbinary companion and the eclipsing binary is coplanar, its mass would correspond to a giant planet. This hypothetical giant planet is moving in a circular orbit of radius $\sim5.75(\pm2.02)$ AU around its host star., Comment: 19 pages, 5 figures

SDSS J143547.87+373338.5 is a detached eclipsing binary that contains a white dwarf with a mass of 0.5 Mo and a fully convective star with a mass of 0.21 Mo. The eclipsing binary was monitored photometrically from 2009 March 24 to 2015 April 10, by using two 2.4-m telescopes in China and in Thailand. The changes in the orbital period are analyzed based on eight newly determined eclipse times together with those compiled from the literature. It is found that the observed-calculated (O-C) diagram shows a downward parabolic change that reveals a continuous period decrease at a rate of s s-1. According to the standard theory of cataclysmic variables, angular momentum loss (AML) via magnetic braking (MB) is stopped for fully convective stars. However, this period decrease is too large to be caused by AML via gravitational radiation (GR), indicating that there could be some extra source of AML beyond GR, but the predicted mass-loss rates from MB seem unrealistically large. The other possibility is that the O-C diagram may show a cyclic oscillation with a period of 7.72 years and a small amplitude of 0.000525. The cyclic change can be explained as the light-travel-time effect via the presence of a third body because the required energy for the magnetic activity cycle is much larger than that radiated from the secondary in a whole cycle. The mass of the potential third body is determined to be Mo when a total mass of 0.71 Mo for SDSS J143547.87+373338.5 is adopted. For orbital inclinations , it would be below the stable hydrogen-burning limit of M3 ∼ 0.072 Mo, and thus the third body would be a brown dwarf., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata

Mass transfer and accretion are very important to understand the evolution and observational properties of cataclysmic variables (CVs). Due to the lack of an accretion disk, eclipsing profiles of polars are the best source to study the character of mass transfer in CVs. By analyzing long-term photometric variations in the eclipsing polar HU Aqr, the property of mass transfer and accretion are investigated. The correlation between the brightness state change and the variation of the ingress profile suggests that both the accretion hot spot and the accretion stream are produced instantaneously. The observations clearly show that it is the variation of mass transfer causing the brightness state changes that is a direct evidence of variable mass transfer in a CV. It is shown that it is the local dark-spot activity near the L1 point to cause the change of the mass transfer rather than the activity cycles of the cool secondary star. Our results suggest that the evolution of CVs is more complex than that predicted by the standard model and we should consider the effect of variable mass accretion in nova and dwarf nova outbursts., Facultad de Ciencias Astronómicas y Geofísicas

By using our twelve new CCD times of light minimum of OY Carinae (OY Car) together with those collected from the literature, it is found that the O-C curve of OY Car shows a downward parabola with an amplitude of 27.8 s and a cyclic change of a period 14.0 yr. The period decrease is opposite to the hypothesis of mass transfer, and it cannot be explained by angular momentum loss via gravitational radiation. The Rappaport et al. (1983)’s magnetic braking (MB) prescription is adopted to explain the observed orbital period decrease. The cyclic change of period is analyzed with the light travel-time effect that originates from gravitational influence of a third body. The mass of the third star is determined to be M3sini‧=0.008097(±0.000014) M⊙=8.48(±0.02) MJup, suggesting that it may be a critical substellar object between brown dwarf and giant planet. If the orbital inclination of the third body equals 90°, the distance between the third body and the mass centre of the whole system is about 6.18(±0.45) AU. Fil: Han, Z. T. . Chinese Academy Of Sciences; República de China Fil: Qian, S. B.. Chinese Academy Of Sciences; República de China Fil: Fernandez Lajus, Eduardo Eusebio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Instituto de Astrofísica de la Plata; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina Fil: Liao, W. P.. Chinese Academy Of Sciences; República de China Fil: Zhang, J.. Chinese Academy Of Sciences; República de China

To investigate the effects of free radicals (FRs) and amyloid beta protein (A beta 1-40) on the functions of expressed neurotransmitter receptors (NRs) from rat brains in Xenopus oocytes.Total RNA and Messenger RNA (mRNA) was prepared from 3-month-old Wistar rat brain tissues with Promega kits and microinjected into mature Xenopus oocytes (stage V - VI) with 50 nl (50 ng) for each oocyte for receptor expression and their currents were recorded with double electrode voltage clamp technique. Superoxide anion free radicals (SAFRs) and A beta 1-40 was added 12 h, 24 h, 96 h to incubation solution before recording.The results showed that oocytes expressed mACh, glutamate, dopamine, serotonin and gamma-aminobutyric acid receptors. The current characteristics of these receptors were inward currents carried by chloride ion with their equilibrium potentials close to - 22 mV. A beta 1-40 and free radicals had a kind of inhibitory effect on the expressed GluR. When treated with 60 nmol/L A beta 1-40 over 24 h, the currents of GluR significantly decreased (25% off, P:0.01). When oocytes were co-treated with 60 nmol/L A beta 1-40 and SAFRs over a period of 12 h, the currents of glutamate receptor significantly decreased (21% of P0.05), and the decreased percentage reached 52% over 24h co-treated with 60 nmol/L A beta 1-40 and SAFRs. Vitamin E had partial antagonistic effect against these effects.The result suggests that A beta has a kind of inhibitory effects upon glutamate receptor, which is similar to those of free radicals. Their effects can be antagonized by vitamin E. This implies that A beta may play roles via inhibiting receptor function in pathophysiology of Alzheimer's disease.

Our recent studies demonstrated that 12-O-tetradecanoylphorbol-13-acetate (TPA) has pharmacological activity for the treatment of acute myelocytic leukemia patients. In the present study, we investigated the potential synergistic effect of all-trans retinoic acid (RA), 1alpha,25-dihydroxyvitamin D3 (VD3), and sodium butyrate (NaB) on TPA-induced differentiation in HL-60 human promyelocytic leukemia cells. The cells were treated once with these agents for 48 h or treated every 24 h for 96 h. Treatment of HL-60 cells once with TPA, RA, VD3, or NaB for 48 h resulted in concentration-dependent growth inhibition and cell differentiation. At clinically achievable concentrations, TPA (0.16 nM) increased the number of adherent cells and RA (0.1-1 microM) increased the number of nitroblue tetrazolium (NBT)-positive cells. The combinations of TPA (0.16 nM) with RA (0.1-1 microM), VD3 (1 nM), or NaB (100 microM) for 48 h synergistically increased differentiation as measured by the formation of adherent cells (Por = 0.01). Moreover, cells treated with various combinations of low concentrations of TPA, RA, VD3, and NaB every 24 h for 96 h resulted in a further decrease in cell growth and an increase in differentiation. At clinically achievable concentrations, the strongest stimulation of differentiation was achieved in cells treated with a "cocktail" that combined TPA, RA, VD3, and NaB. The synergistic effect of combinations of TPA with RA or NaB at clinically effective concentrations on HL-60 cell differentiation suggests that the combination of these agents may improve the therapeutic efficacy of TPA for the treatment of acute promyelocytic leukemia (APL) patients. A differentiation "cocktail" that combines TPA, RA, VD3, and NaB may provide an even more effective strategy for improving the therapeutic efficacy of TPA and RA.

The effects of topically applied 12-O-tetradecanoylphorbol-13-acetate (TPA) on the level of ascorbic acid in the epidermis and the effects of topically applied ascorbic acid, ascorbyl palmitate (a synthetic lipophilic derivative of ascorbic acid), palmitic acid and sorbitan monopalmitate on TPA-induced epidermal ornithine decarboxylase activity, epidermal DNA synthesis, and the promotion of skin tumors were evaluated in female CD-1 mice. Topical application of 5 or 16 nmol of TPA resulted in a 45-50% decrease in the amount of ascorbic acid per mg protein in mouse epidermis at 5 h after TPA application. Large topical doses of ascorbic acid inhibited TPA-induced tumor promotion in mouse epidermis, but smaller doses were inactive. The topical application of relatively small doses of ascorbyl palmitate had a marked inhibitory effect on TPA-induced ornithine decarboxylase activity, DNA synthesis, and tumor promotion in mouse epidermis. Ascorbic acid, palmitic acid, and sorbitan monopalmitate were less effective than ascorbyl palmitate as inhibitors of tumor promotion. The topical application of 4 mumol of ascorbyl palmitate inhibited by 60-76% the induction of epidermal ornithine decarboxylase activity and DNA synthesis that occurred after a single topical application of 2 nmol of TPA whereas similar doses of ascorbic acid had no inhibitory effect. The topical application of 4 mumol of ascorbyl palmitate together with 5 nmol of TPA twice weekly for 20 weeks to previously initiated mice inhibited by 91% the number of tumors per mouse.