Periodicities in the occurrence of aurora as indicators of solar variability

A compilation of records of the aurora observed in China from the Time of the Legends (2000 - 3000 B.C.) to the mid-18th century has been used to infer the frequencies and strengths of solar activity prior to modern times. A merging of this analysis with auroral and solar activity patterns during the last 200 years provides basically continuous information about solar activity during the last 2000 years. The results show periodicities in solar activity that contain average components with a long period (approx. 412 years), three middle periods (approx. 38 years, approx. 77 years, and approx. 130 years), and the well known short period (approx. 11 years)

Temporal evolution of depolarization and magnetic field of FRB 20201124A

Fast radio bursts (FRBs) are energetic millisecond phenomena in radio band. Polarimetric studies of repeating FRBs indicate that many of these sources occupy extreme and complex magneto-ionized environments. Recently, a frequency-dependent depolarization has been discovered in several repeating FRBs. However, the temporal evolution of polarization properties is limited by the burst rate and observational cadence of telescopes. In this letter, the temporal evolution of depolarization in repeating FRB 20201124A is explored. Using the simultaneous variation of rotation measure and dispersion measure, we also measure the strength of a magnetic field parallel to the line-of-sight. The strength ranges from a few $\mu {\rm G}$ to $10^3\ \mu {\rm G}$. In addition, we find that the evolution of depolarization and magnetic field traces the evolution of rotation measure. Our result supports that the variation of depolarization, rotation measure and the magnetic field are determined by the same complex magneto-ionized screen surrounding the FRB source. The derived properties of the screen are consistent with the wind and the decretion disk of a massive star.Comment: 9 pages, 3 figures, 1 table, accept for publication in ApJ

A Cellular Automata Model with Probability Infection and Spatial Dispersion

In this article, we have proposed an epidemic model by using probability cellular automata theory. The essential mathematical features are analyzed with the help of stability theory. We have given an alternative modelling approach for the spatiotemporal system which is more realistic and satisfactory from the practical point of view. A discrete and spatiotemporal approach are shown by using cellular automata theory. It is interesting to note that both size of the endemic equilibrium and density of the individual increase with the increasing of the neighborhood size and infection rate, but the infections decrease with the increasing of the recovery rate. The stability of the system around the positive interior equilibrium have been shown by using suitable Lyapunov function. Finally experimental data simulation for SARS disease in China and a brief discussion conclude the paper

Trigger efficiencies at BES III

Trigger efficiencies at BES III were determined for both the J/psi and psi' data taking of 2009. Both dedicated runs and physics datasets are used; efficiencies are presented for Bhabha-scattering events, generic hadronic decay events involving charged tracks, dimuon events and psi' -> pi+pi-J/psi, J/psi -> l+l- events (l an electron or muon). The efficiencies are found to lie well above 99% for all relevant physics cases, thus fulfilling the BES III design specifications.Comment: 6 pages, 4 figure

Persistence, extinction and spatio-temporal synchronization of SIRS cellular automata models

Spatially explicit models have been widely used in today's mathematical ecology and epidemiology to study persistence and extinction of populations as well as their spatial patterns. Here we extend the earlier work--static dispersal between neighbouring individuals to mobility of individuals as well as multi-patches environment. As is commonly found, the basic reproductive ratio is maximized for the evolutionary stable strategy (ESS) on diseases' persistence in mean-field theory. This has important implications, as it implies that for a wide range of parameters that infection rate will tend maximum. This is opposite with present results obtained in spatial explicit models that infection rate is limited by upper bound. We observe the emergence of trade-offs of extinction and persistence on the parameters of the infection period and infection rate and show the extinction time having a linear relationship with respect to system size. We further find that the higher mobility can pronouncedly promote the persistence of spread of epidemics, i.e., the phase transition occurs from extinction domain to persistence domain, and the spirals' wavelength increases as the mobility increasing and ultimately, it will saturate at a certain value. Furthermore, for multi-patches case, we find that the lower coupling strength leads to anti-phase oscillation of infected fraction, while higher coupling strength corresponds to in-phase oscillation.Comment: 12page

Domain decomposition for boundary integral equations via local multi-trace formulations

Abstract We review the ideas behind and the construction of so-called local multitrace boundary integral equations for second-order boundary value problems with piecewise constant coefficients. These formulations have received considerable attention recently as a promising domain-decomposition approach to boundary element methods

Re-expression of ARHI (DIRAS3) induces autophagy in breast cancer cells and enhances the inhibitory effect of paclitaxel

<p>Abstract</p> <p>Background</p> <p><it>ARHI </it>is a Ras-related imprinted gene that inhibits cancer cell growth and motility. ARHI is downregulated in the majority of breast cancers, and loss of its expression is associated with its progression from ductal carcinoma <it>in situ </it>(DCIS) to invasive disease. In ovarian cancer, re-expression of ARHI induces autophagy and leads to autophagic death in cell culture; however, ARHI re-expression enables ovarian cancer cells to remain dormant when they are grown in mice as xenografts. The purpose of this study is to examine whether ARHI induces autophagy in breast cancer cells and to evaluate the effects of ARHI gene re-expression in combination with paclitaxel.</p> <p>Methods</p> <p>Re-expression of ARHI was achieved by transfection, by treatment with trichostatin A (TSA) or by a combination of TSA and 5-aza-2'-deoxycytidine (DAC) in breast cancer cell cultures and by liposomal delivery of ARHI in breast tumor xenografts.</p> <p>Results</p> <p>ARHI re-expression induces autophagy in breast cancer cells, and ARHI is essential for the induction of autophagy. When ARHI was re-expressed in breast cancer cells treated with paclitaxel, the growth inhibitory effect of paclitaxel was enhanced in both the cell culture and the xenografts. Although paclitaxel alone did not induce autophagy in breast cancer cells, it enhanced ARHI-induced autophagy. Conversely, ARHI re-expression promoted paclitaxel-induced apoptosis and G2/M cell cycle arrest.</p> <p>Conclusions</p> <p>ARHI re-expression induces autophagic cell death in breast cancer cells and enhances the inhibitory effects of paclitaxel by promoting autophagy, apoptosis, and G2/M cell cycle arrest.</p

Psychological Typhoon Eye in the 2008 Wenchuan Earthquake

BACKGROUND: On May 12, 2008, an earthquake measuring 8.0 on the Richter scale jolted Wenchuan, China, leading to 69,227 deaths and 374,643 injured, with 17,923 listed as missing as of Sept. 25, 2008, and shook the whole nation. We assessed the devastating effects on people's post-earthquake concern about safety and health. METHODOLOGY/PRINCIPAL FINDINGS: From June 4 to July 15, 2008, we surveyed a convenience sample of 2,262 adults on their post-earthquake concern about safety and health. Residents in non-devastated areas (Fujian and Hunan Provinces, and Beijing) and devastated areas (Sichuan and Gansu Provinces) responded to a questionnaire of 5 questions regarding safety measures, epidemic disease, medical workers, psychological workers, and medication. The ANOVAs showed a significant effect of residential devastation level on the estimated number of safety measures needed, the estimated probability of the outbreak of an epidemic, and the estimated number of medical and psychological workers needed (Ps<0.001). The post-earthquake concern decreased significantly as the level of residential devastation increased. Because of the similarity with the meteorological phenomenon of the eye of a typhoon, we dubbed these findings a "Psychological Typhoon Eye": the closer to the center of the devastated areas, the less the concern about safety and health a resident felt. CONCLUSIONS/SIGNIFICANCE: Contrary to common perception and ripple effect that the impact of an unfortunate event decays gradually as ripples spread outward from a center, a "Psychological Typhoon Eye" effect was observed where the post-earthquake concern was at its lowest level in the extremely devastated areas. The resultant findings may have implications for Chinese governmental strategies for putting "psychological comfort" into effect

One-Step Synthesis of Monodisperse In-Doped ZnO Nanocrystals

A method for the synthesis of high quality indium-doped zinc oxide (In-doped ZnO) nanocrystals was developed using a one-step ester elimination reaction based on alcoholysis of metal carboxylate salts. The resulting nearly monodisperse nanocrystals are well-crystallized with typically crystal structure identical to that of wurtzite type of ZnO. Structural, optical, and elemental analyses on the products indicate the incorporation of indium into the host ZnO lattices. The individual nanocrystals with cubic structures were observed in the 5% In–ZnO reaction, due to the relatively high reactivity of indium precursors. Our study would provide further insights for the growth of doped oxide nanocrystals, and deepen the understanding of doping process in colloidal nanocrystal syntheses

A millisecond quantum memory for scalable quantum networks

Scalable quantum information processing critically depends on the capability of storage of a quantum state. In particular, a long-lived storable and retrievable quantum memory for single excitations is of crucial importance to the atomic-ensemble-based long-distance quantum communication. Although atomic memories for classical lights and continuous variables have been demonstrated with milliseconds storage time, there is no equal advance in the development of quantum memory for single excitations, where only around 10 $\mu$s storage time was achieved. Here we report our experimental investigations on extending the storage time of quantum memory for single excitations. We isolate and identify distinct mechanisms for the decoherence of spin wave (SW) in atomic ensemble quantum memories. By exploiting the magnetic field insensitive state, ``clock state", and generating a long-wavelength SW to suppress the dephasing, we succeed in extending the storage time of the quantum memory to 1 ms. Our result represents a substantial progress towards long-distance quantum communication and enables a realistic avenue for large-scale quantum information processing.Comment: 11pages, 4 figures, submitted for publicatio