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SN 2019yvr is the second Type Ib supernova (SN) with a possible direct detection of its progenitor (system); however, the spectral energy distribution (SED) of the pre-explosion source appears much cooler and overluminous than an expected helium-star progenitor. Using Hubble Space Telescope (HST) images and MUSE integral-field-unit (IFU) spectroscopy, we find the SN environment contains three episodes of star formation; the low ejecta mass suggests the SN progenitor is most likely from the oldest population, corresponding to an initial mass of 10.4$^{+1.5}_{-1.3}$ $M_\odot$. The pre-explosion SED can be reproduced by two components, one for the hot and compact SN progenitor and one for a cool and inflated yellow hypergiant (YHG) companion that dominates the brightness. Thus, SN 2019yvr could possibly be the first Type Ib/c SN for which the progenitor's binary companion is directly detected on pre-explosion images. Both the low progenitor mass and the YHG companion suggest significant binary interaction during their evolution. Similar to SN 2014C, SN 2019yvr exhibits a metamorphosis from Type Ib to Type IIn, showing signatures of interaction with hydrogen-rich circumstellar material (CSM) at >150 days; our result supports enhanced pre-SN mass loss as an important process for hydrogen-poor stars at the low mass end of core-collapse SN progenitors., 15 pages, 9 figures, accepted for publication in MNRAS

Transit Timing Variation (TTV) of hot Jupiters provides direct observational evidence of planet tidal dissipation. Detecting tidal dissipation through TTV needs high precision transit timings and long timing baselines. In this work, we predict and discuss the potential scientific contribution of SiTian Survey in detecting and analyzing exoplanet TTV. We develop a tidal dissipation detection pipeline for SiTian Survey that aims at time-domain astronomy with 72 1-meter optical telescopes. The pipeline includes the modules of light curve deblending, transit timing obtaining, and TTV modeling. SiTian is capable to detect more than 25,000 exoplanets among which we expect $\sim$50 sources showing evidence of tidal dissipation. We present detection and analysis of tidal dissipating targets, based on simulated SiTian light curves of XO-3b and WASP-161b. The transit light curve modeling gives consistent results within 1$\sigma$ to input values of simulated light curves. Also, the parameter uncertainties predicted by Monte-Carlo Markov Chain are consistent with the distribution obtained from simulating and modeling the light curve 1000 times. The timing precision of SiTian observations is $\sim$ 0.5 minutes with one transit visit. We show that differences between TTV origins, e.g., tidal dissipation, apsidal precession, multiple planets, would be significant, considering the timing precision and baseline. The detection rate of tidal dissipating hot Jupiters would answer a crucial question of whether the planet migrates at an early formation stage or random stages due to perturbations, e.g., planet scattering, secular interaction. SiTian identified targets would be constructive given that the sample would extend tenfold., Comment: Accept for publication to RAA

Single-line spectroscopic binaries recently contribute to the stellar-mass black hole discovery, independently of the X-ray transient method. We report the identification of a single-line binary system LTD064402+245919, with an orbital period of 14.50 days. The observed component is a subgiant with a mass of 2.77$\pm$0.68M$_{\odot}$, radius 15.5$\pm$2.5R$_{\odot}$, effective temperature $T_{\rm eff}$ 4500$\pm$200K, and surface gravity log\emph{g} 2.5$\pm$0.25dex. The discovery makes use of the LAMOST time-domain (LAMOST-TD) and ZTF survey. Our general-purpose software pipeline applies the Lomb-Scargle periodogram to determine the orbital period and uses machine-learning to classify the variable type from the folded light curves. We apply a combined model to estimate the orbital parameters from both the light and radial velocity curves, taking constraints on the primary star mass, mass function, and detection limit of secondary luminosity into consideration. We obtain a radial velocity semi-amplitude of 44.6$\pm$1.5 km s$^{-1}$, mass ratio of 0.73$\pm$0.07, and an undetected component mass of 2.02$\pm$0.49M$_{\odot}$ when the type of the undetected component is not set. We conclude that the inclination is not well constrained, and that the secondary mass is larger than 1M$_{\odot}$ when the undetected component is modelled as a compact object. According to our investigations using an MCMC simulation, increasing the spectra SNR by a factor of 3 would enable the secondary light to be distinguished (if present). The algorithm and software in this work are able to serve as general-purpose tools for the identification of compact objects quiescent in X-rays., Accepted by ApJ

We present a novel, iterative method using an empirical Bayesian approach for modeling the limb darkened WASP-121b transit from the TESS light curve. Our method is motivated by the need to improve $R_{p}/R_{\ast}$ estimates for exoplanet atmosphere modeling, and is particularly effective with the limb darkening (LD) quadratic law requiring no prior central value from stellar atmospheric models. With the non-linear LD law, the method has all the advantages of not needing atmospheric models but does not converge. The iterative method gives a different $R_{p}/R_{\ast}$ for WASP-121b at a significance level of 1$\sigma$ when compared with existing non-iterative methods. To assess the origins and implications of this difference, we generate and analyze light curves with known values of the limb darkening coefficients (LDCs). We find that non-iterative modeling with LDC priors from stellar atmospheric models results in an inconsistent $R_{p}/R_{\ast}$ at 1.5$\sigma$ level when the known LDC values are as those previously found when modeling real data by the iterative method. In contrast, the LDC values from the iterative modeling yields the correct value of $R_{p}/R_{\ast}$ to within 0.25$\sigma$. For more general cases with different known inputs, Monte Carlo simulations show that the iterative method obtains unbiased LDCs and correct $R_{p}/R_{\ast}$ to within a significance level of 0.3$\sigma$. Biased LDC priors can cause biased LDC posteriors and lead to bias in the $R_{p}/R_{\ast}$ of up to 0.82$\%$, 2.5$\sigma$ for the quadratic law and 0.32$\%$, 1.0$\sigma$ for the non-linear law. Our improvement in $R_{p}/R_{\ast}$ estimation is important when analyzing exoplanet atmospheres., Comment: Accepted by AJ

From Oct. 2019 to Apr. 2020, LAMOST performs a time-domain spectroscopic survey of four $K$2 plates with both low- and med-resolution observations. The low-resolution spectroscopic survey gains 282 exposures ($\approx$46.6 hours) over 25 nights, yielding a total of about 767,000 spectra, and the med-resolution survey takes 177 exposures ($\approx$49.1 hours) over 27 nights, collecting about 478,000 spectra. More than 70%/50% of low-resolution/med-resolution spectra have signal-to-noise ratio higher than 10. We determine stellar parameters (e.g., $T_{\rm eff}$, log$g$, [Fe/H]) and radial velocity (RV) with different methods, including LASP, DD-Payne, and SLAM. In general, these parameter estimations from different methods show good agreement, and the stellar parameter values are consistent with those of APOGEE. We use the $Gaia$ DR2 RV data to calculate a median RV zero point (RVZP) for each spectrograph exposure by exposure, and the RVZP-corrected RVs agree well with the APOGEE data. The stellar evolutionary and spectroscopic masses are estimated based on the stellar parameters, multi-band magnitudes, distances and extinction values. Finally, we construct a binary catalog including about 2700 candidates by analyzing their light curves, fitting the RV data, calculating the binarity parameters from med-resolution spectra, and cross-matching the spatially resolved binary catalog from $Gaia$ EDR3. The LAMOST TD survey is expected to get breakthrough in various scientific topics, such as binary system, stellar activity, and stellar pulsation, etc., Comment: 22 pages, 19 figures, 7 tables. Accepted for publication in RAA

A precise transit ephemeris serves as the premise for follow-up exoplanet observations. We compare TESS Objects of Interest (TOI) transit timings of 262 hot Jupiters with the archival ephemeris and find 31 of them having TOI timing offsets, among which WASP-161b shows the most significant offset of -203.7$\pm$4.1 minutes. The median value of these offsets is 17.8 minutes, equivalent to 3.6 $\sigma$. We generate TESS timings in each sector for these 31 hot Jupiters, using a self-generated pipeline. The pipeline performs photometric measurements to TESS images and produces transit timings by fitting the light curves. We refine and update the previous ephemeris, based on these TESS timings (uncertainty $\sim$ 1 minute) and a long timing baseline ($\sim 10$ years). Our refined ephemeris gives the transit timing at a median precision of 0.82 minutes until 2025 and 1.21 minutes until 2030. We regard the timing offsets mainly originating from the underestimated ephemeris uncertainty. All the targets with timing offset larger than 10$\sigma$ present earlier timings than the prediction, which cannot be due to underestimated ephemeris uncertainty, apsidal precision, or R$\o$mer effect as those effects should be unsigned. For some particular targets, timing offsets are likely due to tidal dissipation. Our sample leads to the detection of period decaying candidates of WASP-161b and XO-3b reported previously., Comment: Submitted to ApJS; 24 pages

Chemical investigation of the ethanol extract of the branch and leaves of Illicium majus resulted in the isolation of four new phenylpropanoid glycosides (1-4) and one new phenolic glycoside (9), along with 13 known ones. Spectroscopic techniques were used to elucidate the structures of the new isolates such as 3-[(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-3-(hydroxymethyl)-2,3-dihydro-1-benzofuran-5-yl]propyl β-D-glucopyranoside (1), [(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-2,3-dihydro-1-benzofuran-3-yl]methyl 2-O-α-L-rhamnopyranosyl-β-D-glucopyranoside (2), [(2R,3S)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-2,3-dihydro-1-benzofuran-3-yl]methyl 2-O-α-L-rhamnopyranosyl-β-D-xylopyranoside (3), 3-[(2R,3S)-3-({[2-O-(4-O-acetyl-α-L-rhamnopyranosyl)-β-D-xylopyranosyl]oxy}methyl)-7-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-2,3-dihydro-1-benzofuran-5-yl]propyl acetate (4), and 4-(2-hydroxyethyl)phenyl 3-O-β-D-glucopyranosyl-β-D-glucopyranoside (9). Free radical scavenging activities of the isolates were elucidated through the DPPH assay method. The most active compounds, 1-O-caffeoyl-β-D-glucopyranose (17) and soulieana acid 1 (18), exhibited moderate radical scavenging activities (IC50 =37.7±4.4 μM and IC50 =97.2±3.4 μM, respectively). The antibacterial activities of the isolates against Staphylococcus aureus and Escherichia coli were also assessed, and no activity was shown at the measured concentration (

Spermatogenesis and sperm maturation are closely related to temperature and require a temperature slightly lower than the normal body temperature. Therefore, high temperature is an important external factor affecting sperm function, and the studies on the underlying mechanisms are of great significance for the treatment of male infertility, improvement of in vitro sperm preservation and further elucidation of spermatogenesis and sperm maturation. It is known currently that the influence of high temperature on sperm involves genetic material, morphology, survival rate, motility and fertility, most of which have been found in various species and may be attributed to the conserved common process or common substances in spermatogenesis and maturation. An overwhelming majority of the influencing factors produce negative effects and a very few have positive ones, and their action mechanisms are mostly unknown. This review summarizes the results of current studies on the effect of high temperature on spermatogenesis and sperm maturation and on the sperm function in various species.

We present a re-analysis of transit depths of KELT-19Ab, WASP-156b, and WASP-121b, including data from the Transiting Exoplanet Survey Satellite (TESS). The large $\sim$21$\arcsec$ TESS pixels and point spread function result in significant contamination of the stellar flux by nearby objects. We use Gaia data to fit for and remove this contribution, providing general-purpose software for this correction. We find all three sources have a larger inclination, compared to earlier work. For WASP-121b, we find significantly smaller values (13.5 degrees) of the inclination when using the 30 minutes cadence data compared to the 2 minutes cadence data. Using simulations, we demonstrate that the radius ratio of exoplanet to star ($R_{p}/R_{\ast}$) is biased small relative to data taken with a larger sampling interval although oversampling corrections mitigate the bias. This is particularly important for deriving sub-percent transit differences between bands. We find the radius ratio of exoplanet to star ($R_{p}/R_{\ast}$) in the TESS band is 7.5$\sigma$ smaller than previous work for KELT-19Ab, but consistent to within $\sim$2$\sigma$ for WASP-156b and WASP-121b. The difference could be due to specific choices in the analysis, not necessarily due to the presence of atmospheric features. The result for KELT-19Ab possibly favors a haze-dominated atmosphere. We do not find evidence for the $\sim$0.95\,$\mu$m water feature contaminating transit depths in the TESS band for these stars but show that with photometric precision of 500ppm and with a sampling of about 200 observations across the entire transit, this feature could be detectable in a more narrow $z-$band., Comment: Accepted to AJ

This study was to compare the clinical characteristics and prognosis of Waldeyer's ring diffuse large B-cell lymphoma (WR-DLBCL) and lymph node DLBCL (LN-DLBCL) in the rituximab era. Before propensity score-matched (PSM), WR-DLBCL group shows more favorable clinical characteristics than LN-DLBCL group. After PSM, there was no significant difference in the response rate and survivals between them. The 5-year PFS and OS rates were 65.0% and 78.6% for WR-DLBCL group, respectively, and 53.7% and 66.1% for LN-DLBCL group, respectively. In WR-DLBCL group, ECOG score, Ann Arbor stage, B symptoms and IPI were associated with poor PFS and OS. In LN-DLBCL group, ECOG score, Ann Arbor stage, LDH, and IPI were significant factors to PFS and OS. Multivariate analysis showed that Ann Arbor stage was the only significant factor to PFS for WR-DLBCL group, for LN-DLBCL group, Ann Arbor stage and IPI were independent factors to PFS, LDH was the only significant factor to OS. WR-DLBCL was associated with more favorable clinical characteristics compared with LN-DLBCL, whereas, WR involvement itself did not have a real favorable prognostic significance. The PFS and OS of DLBCL were largely dependent on other prognostic factors such as Ann Arbor stage, LDH or IPI.

Two new compounds, jiadifenlactone acid monomethyl ester (1) and jiadifenin (3), and five known compounds were isolated from the fruits of I. jiadifengpi. Their structures were determined using spectroscopic techniques, including 1D, 2D NMR and HR-ESI-MS experiments. The relative stereochemistry of jiadifenlactone acid monometheyl ester (1) was further confirmed by X-ray crystallographic data. All isolates were evaluated for their effects on nerve growth factor (NGF)-mediated neurite outgrowth in pheochromocytoma (PC12) cells and two compounds showed promoting effects.

A novel fluorescent probe 4 for hydrazine based on pyrazoline-derived was designed and synthesized. The selective deprotection of phthalimide group of the probe by hydrazine led to a dramatic fluorescent enhancement (∼84.7 folds) at 490 nm within 4 min in the aqueous solution. The limit of detection is 0.0622 μM (1.99 ppb) which is much lower than the U.S. Environmental Protection Agency standard (10 ppb). Notably, probe 4 could be used to detect hydrazine in gas state with different concentrations through color changes from readily prepared strips. Additionally, probe 4 could also be applied to monitor hydrazine in living cells by biological imaging.

Methoxycarbonyl etomidate (MOC-etomidate) and cyclopropyl methoxycarbonyl metomidate (CPMM) are rapidly metabolized "soft" etomidate analogs. CPMM's duration of hypnotic effect is context insensitive, whereas MOC-etomidate's is not. In this study, we tested the hypothesis that CPMM's effect is context insensitive because, unlike MOC-etomidate, its metabolite fails to reach physiologically important concentrations in vivo even with prolonged continuous infusion.We compared the potencies with which MOC-etomidate and CPMM activate α1(L264T)β3γ2 γ-aminobutyric acid type A receptors and induce loss-of-righting reflexes (i.e., produce hypnosis) in tadpoles with those of their metabolites (MOC-etomidate's carboxylic acid metabolite [MOC-ECA] and CPMM's carboxylic acid metabolite [CPMM-CA], respectively). We measured metabolite concentrations in the blood and cerebrospinal fluid of Sprague-Dawley rats on CPMM infusion and compared them with those achieved with MOC-etomidate infusion. We measured the rates with which brain tissue from Sprague-Dawley rats metabolize MOC-etomidate and CPMM.Both analogs and their metabolites enhanced γ-aminobutyric acid type A receptor function and induced loss-of-righting reflexes in a concentration-dependent manner. However, in these 2 assays, CPMM-CA's potency relative to its parent hypnotic was approximately 1:4900 and 1:1900, respectively, whereas MOC-ECA's was only approximately 1:415 and 1:390, respectively. With 2-hour CPMM infusions, CPMM-CA reached respective concentrations in the blood and cerebrospinal fluid that were 2 and3 orders of magnitude lower than that which produced hypnosis. CPMM was metabolized by the brain tissue at a rate that is approximately 1/15th that of MOC-etomidate.Hypnotic recovery after CPMM administration is context insensitive because its metabolite does not accumulate to hypnotic levels in the central nervous system. This reflects the very large potency ratio between CPMM and CPMM-CA and the resistance of CPMM to metabolism by esterases present in the brain.

A label-free colorimetric protocol based on peptide nucleic acid/silver nanoparticles (PNA/AgNPs) has been initially proposed for specific recognition of mRNA. Making use of the controlled silver nanoparticles aggregation/dispersion by PNA/PNA–RNA complex, proto-oncogene c-Myc mRNA detection can be achieved. Moreover, the PNA/AgNPs platform can undergo color change in response to target c-Myc mRNA with single-base-mismatch sensitivity, which could further help in visually identify single nucleotide differences in target genes.

The 21th century is the century of exploring and utilizing the underground space. In the future, more and more people will spend more and more time living or/and working in the underground space. However,we know little about the effect on the health of human caused by the underground environment. Herein,we systematically put forward the strategic conception of the deep-underground medicine,in order to reveal relative effects and mechanism of the potential factors in the deep underground space on human's physiological and psychological healthy,and to work out the corresponding countermeasures. The original deep-underground medicine includes the following items. ①To model different depth of underground environment according to various parameters (such as temperature,radiation,air pressure, rock,microorganism), and to explore their quantitative character and effects on human health and mechanism. ② To study the psychological change, maintenance of homeostasis and biothythm of organism in the deep underground space. ③ To learn the association between psychological healthy of human and the depth, structure, physical environment and working time of underground space. ④ To investigate the effect of different terrane and lithology on healthy of human and to deliberate their contribution on organism growth. ⑤ To research the character and their mechanism of growth,metabolism,exchange of energy,response of growth, aging and adaptation of cells living in deep underground space. ⑥ To explore the physiological feature,growth of microbiome and it's interaction with host in the deep underground space. ⑦ To develop deep-underground simulation space, the biologically medical technology and equipments. As a research basis,a deep-underground medical lab under a rock thickness of about 1 470 m has been built,which aims to operate the research of the effect on living organism caused by different depth of underground environment.

Two new compounds, 2S-hydroxyl-jiadifenolide (1) and jiadifenlactone acid (2), and eight known compounds were isolated from the fruits of Illicium jiadifengpi. Their structures were analysed using several spectroscopic techniques, including 1D-, 2D-NMR and HR-ESI-MS experiments. The anti-hepatitis B virus (HBV) activities of the isolates were evaluated via HBV transfection of the Hep G2.2.15 cell line. The inhibitory rates of the most active compounds, compounds 4 and 5, on the HBeAg and HBsAg expression were 28.85 ± 3.15% and 17.53 ± 1.81% and 37.93 ± 2.74% and 23.47 ± 9.52% at concentrations of 64.94 μM and 61.35 μM, respectively.

Pilomatrix carcinoma (PC) is a rare neoplasm, particularly in the parotid region. Thus, it is easily misdiagnosed and an optimal treatment regimen has not yet been established. The present study reports the case of a 43-year-old female who presented with a PC of the parotid region and reviews the associated published literature. The patient underwent three surgical excisions prior to the tumor being completely removed, and was misdiagnosed four times prior to the correct diagnosis. Once the tumor was completely removed, the patient received radiation therapy (RT). At the 2-year follow-up, the patient remained free of local recurrence and metastasis. To the best of our knowledge, only 3 cases of PC on the parotid region have been reported. Although an optimal treatment regimen has not been established, surgery with wide margins is recommended, with RT and chemotherapy producing mixed results.

Oridonin, which is isolated from Chinese herb Rabdosia rubescens (Hemsl.) Hara, has been implicated in regulation of tumor cell migration and invasion. In this study, treatment with oridonin enhanced the phosphorylation of myosin regulatory light chain (T18/S19) that regulates the ATPase activity of myosin IIA. Meanwhile, stress fibers were significantly more prominent after oridonin incubation, which impaired cell migration in transwell migration assays. All of these effects may be caused by the decreased interaction between myosin IIA and myosin phosphatase complex, but not kinases. Our data provide clear evidence of this novel pharmacological function for oridonin in treating cancer cell migration.

A pushrod harmonic institution which is consisted of harmonic planetary and cam mechanism is proposed. As a result, speed-down device of low-speed motor is changed from external installed to interior installed. Design goals of the transmission with small size, light weight and low cost is achieved. Based on the mechanism principle analysis, the theoretical profile equation of the pushrod roller is deduced, then the displacement, velocity and acceleration equation of a random points are got by the analysis method. It is helpful to analyze the change of each motion parameters and the amplitude for the influence of the movement characteristics, at the same time provides evidence for mechanism simulation, kinematics parameters optimization and high-quality manufacturing of the equipment.

The vibration-stress field could be formed by high vibration intensity in vibration machine to improve the ability of the collision, shock, shear and extrusion for the system, and it also can avoid plugging screen for vibration screening machine, which could make for solving some special requirements of the vibration machine. To research the vibration machines strongly nonlinear and high vibration intensity characteristic such as certain excitation and uncertain response, the vibration machine with its double-mass is built, and its vibration exciter uses two partial blocks as vibration motor. In addition, dynamic vibration differential equation is established. To achieve high vibration intensity results based on the vibration machines safe working, the advanced control based on the SCM and Intelligent frequency conversion is put forward, and the advanced control system with its host computer, frequency converter, SCM, charge-amplifier, sensor and the vibration machine is been established.

To break through the drawbacks of the one-mass vibrating screen like plugging screen, high noise and etc., a new vibration screen with two-mass and high energy which could generate transient high vibration intensity was analyzed. To meet the requirements of energy-saving and system stability, a spring with nonlinear and hard features was used in the main vibration system. In this case, the springs stiffness could change along with the vibration intensity. The stiffness of the vibration isolation spring could be determined by analyzing the vibration isolation coefficient, and then the hollow cylindrical rubber spring with internal damping was adopted in the vibration isolation system. On the one hand, this vibration isolation spring could effectively absorb transient high vibration intensity which passed from main vibrating spring to the lower mass. On the other hand, it could achieve good effect of vibration isolation between the lower mass and the foundation. Base on field testing, the vibration intensity was increased by 28%, meanwhile, the noise was reduced by 4% and the impact vibration to foundation was reduced by 24% , which successfully solved the plugging screen problem and also verified the validity of the vibration isolation system.

Some special operations of chaotic vibration mill require not only has a certain frequency high vibration intensity but also can effectively control overtime and over-limited of vibration intensity. The validity of advanced control decision is key technology for chaotic vibration mill to achieve some special operations such as super-hard and superfine grinding. Through the application based on the intelligent frequency conversion of PLC advanced control system, the high vibration intensity exceeds 15 presents discontinuously and the transient super-high vibration intensity exceeds 20 presents 3 times shortly. By comparing with conventional vibration mill, it shows that the advance control system can control high vibration intensity effectively, and the engineering effects of the deaggregation and refinement of super-hard and superfine grinding is obtained.

An intelligent frequency advance control system based on Single-Chip-Microcomputer is developed. By simulation debugging of the system, existing problems is find, and the solutions to this problems are proposed so that improve the control system. Comparing with conventional vibration mill, the high vibration intensity(≥18) with certain frequency of the advance control system presents discontinuously, and super-high vibration intensity(≥20) presents several times. The result shows the advance control system can not only achieve the high vibration intensity with certain frequency, but also effectively control overrun and overtime of vibration intensity. The engineering effect of effective deaggregation and grain refinement in the super-hard powder superfine grinding is gained.

A intelligent variable frequency amplitude reduction advance control system whose single-chip-microcomputer act as the core controller is built, and the vibration frequency curve with multiple wave variable sine increase and decrease periodic cycle is applied as the input frequency curve, which made the vibration mill have multiple frequency and amplitude. The control methods are studied, and the operation program is debugged. By using the sensor signal amplification, A/D conversion, on-line monitoring, data mining, and the forecast of the extreme value point of the vibration intensity and its distribution, and then by conducting the judgment, detection, correction and real-time feedback of constraint condition to achieve advance control of vibration intensity over-limit and over-time.

To achieve the design goals of transmission with small size, light weight and low cost, the pushrod harmonic mechanism which is consist of harmonic planetary and cam mechanism is proposed, and the speed-down device of low-speed motor is changed from external installed to interior installed. Based on the mechanism principle analysis, derivation of contour equation and kinematics analysis, the centroid movement theorem of the pushrod roller and the mechanism dynamic is analyzed when the sports vice friction was considered and ignored. The total reaction force and the action line are gained. These data can provide evidence for mechanism simulation, efficiency analysis and reliability design.

The geometries of the –CH3 and –CH2OH modified β-cyclodextrin {i.e. (β- CD(R) m ( R = –CH3, –CH2OH ; m = 0, 1, …, 7)} and the energetical behaviors of one trans-Resveratrol (TR) molecule including inside their cavities were studied by using ONIOM (B3LYP/6-31G*:PM3) method. The most outstanding geometrical characteristic of the β- CD(R) m is that their inside radius (r) are varied with different chemical modifications. The released energies for one TR molecule passing through or rotating inside the cavities of β- CD(R) m are predicted to be related with the inclusion schemes (from narrow side or wide side of the cavity), the values of the inside radius r, and the types (– CH 3 or – CH 2 OH ) and number (m) of the substituted R groups. Our calculations also suggest that the formation of H-bonds in the inclusion interaction is the main factor to stabilize the formed inclusion complexes, i.e. the TR @β- CD(R) m( R = –CH3, –CH2OH ; m = 0, 1, …, 7).

BACKGROUND We previously developed 2 etomidate analogs that retain etomidate's favorable hemodynamic properties but whose adrenocortical effects are reduced in duration or magnitude. Methoxycarbonyl (MOC)-etomidate is rapidly metabolized and ultrashort acting whereas (R)-ethyl 1-(1-phenylethyl)-1H-pyrrole-2-carboxylate (carboetomidate) does not potently inhibit 11β-hydroxylase. We hypothesized that MOC-etomidate's labile ester could be incorporated into carboetomidate to produce a new agent that possesses favorable properties individually found in each agent. We describe the synthesis and pharmacology of MOC-(R)-ethyl 1-(1-phenylethyl)-1H-pyrrole-2-carboxylate (MOC-carboetomidate), a "soft" analog of carboetomidate. METHODS MOC-carboetomidate's octanol:water partition coefficient was determined chromatographically and compared with those of etomidate, carboetomidate, and MOC-etomidate. MOC-carboetomidate's 50% effective concentration (EC(50)) and 50% effective dose for loss of righting reflexes (LORR) were measured in tadpoles and rats, respectively. Its effect on γ-aminobutyric acid A (GABA(A)) receptor function was assessed using 2-microelectrode voltage clamp electrophysiological techniques and its metabolic stability was determined in pooled rat blood using high performance liquid chromatography. Its duration of action and effects on arterial blood pressure and adrenocortical function were assessed in rats. RESULTS MOC-carboetomidate's octanol:water partition coefficient was 3300 ± 280, whereas those for etomidate, carboetomidate, and MOC-etomidate were 800 ± 180, 15,000 ± 3700, and 190 ± 25, respectively. MOC-carboetomidate's EC(50) for LORR in tadpoles was 9 ± 1 μM and its EC(50) for LORR in rats was 13 ± 5 mg/kg. At 13 μM, MOC-carboetomidate enhanced GABA(A) receptor currents by 400% ± 100%. Its metabolic half-life in pooled rat blood was 1.3 min. The slope of a plot of the duration of LORR in rats versus the logarithm of the hypnotic dose was significantly shallower for MOC-carboetomidate than for carboetomidate (4 ± 1 vs 15 ± 3, respectively; P = 0.0004123). At hypnotic doses, the effects of MOC-carboetomidate on arterial blood pressure and adrenocortical function were not significantly different from those of vehicle alone. CONCLUSIONS MOC-carboetomidate is a GABA(A) receptor modulator with potent hypnotic activity that is more rapidly metabolized and cleared from the brain than carboetomidate, maintains hemodynamic stability similar to carboetomidate, and does not suppress adrenocortical function.

The key technology of vibration machine to finish deaggregation and powder refinement is both high vibration Intensity with a certain frequency and steady vibration of frequency conversion control. A frequency conversion control for vibration mill system based on multi-wave variable sinusoidal frequency ascending and descending cycle curve was developed. The frequency conversion control test of vibration mill was finished through sensing signal amplification, analog digital conversion and on line detection. The results show that the high and super-high vibration intensity with certain action time is produced and the effect of multi-amplitude and multi-frequency is acquired. The experimental data show that the super micro grinding of superfine particles is achieved, energy consumption is reduced, the useful life of wearing parts such as bearing is extended, and engineering effects of deaggregation and refinement of super-hard superfine powder are obtained by frequency conversion control.

In order to finish some special operations, the chaotic vibrating motor with two-level partial blocks is constructed. Mechanism principles are designed and dynamics of mechanical model is analyzed by using Lagrange method. Based on the initial sensitivity, non-repetition and complexity of phase-trajectory, many characteristics of chaotic vibration are verified in the vibrating system. It is found the vibrating system with wide power spectrum can achieve some special properties like transient high-intensity, super high-intensity and large vibrating amplitude. It is important to overcome some work barriers and solve some technological bottlenecks of vibrating machinery.

For verifying pile bearing capacity improvement by post-grouting on tip and side and the decrease of building settlement, 10 tip and side post-grouting and 2 unpost-grouting piles are tested by low strain dynamic test, static loading test, stess distribution monitoring and high strain dynamic test, and the building settlement is monitored. It is indicated that all piles length and integrity are meeting the challenge, the post-grouting piles bearing capacity are at least 70% improved than that of unpost-grouting piles, designing pile bearing capacity as 8800kN is safer, the building maximal settlement and the differential settlement is satifying. The preliminary designed 904 piles are reduced to 531 by adopting post-grouting technique and about 20% cost of pile engineering is saved, the proper grouting stata choosing, the accurate grounting volume and pressure controlling in the post-grouting constrution process are needed.

In the present work, explicit water molecule and solvent-field effects on the absorption spectrum of chlorophyll a have been studied using time-dependent density functional theory (TDDFT) method. Calculated results show that the one complex and two water coordinated complexes formed by concerted coordination and hydrogen-bonding interactions would be the most preferable conformations of chlorophyll a in aqueous surroundings. Moreover, four obvious absorption bands are assigned by comparing the theoretically simulated absorption spectra with the experimental ones. The theoretical study shows that the explicit water molecule interactions slightly influence the first absorption band. However, the water coordination and hydrogen-bonding interactions can significantly affect the second absorption band which has a strong red-shift. The solvent-field effect due to the polarity of water on absorptions in Q-bands is relatively smaller than that on absorptions in B-bands. As a consequence, our theoretical study on the absorption spectra in the 350–400 nm region presents that the absorption strength in this region was influenced by the explicit coordination and hydrogen bonding interactions from water molecules, significantly.

The phytochemical investigation of the fruits of Illicium jiadifengpi B. N. Chang led to the isolation of 14 sesquiterpenes (1–14). Among these, compounds 11–14 were identified for the first time from this species. The results indicate that majucin-type sesquiterpenes may be chemotaxonomic markers of I. jiadifengpi.

Jiadifenlactone A ( 1 ), the first example of cleavage of bond [4, 9] of the seco -prezizaane-type sesquiterpenoid with a unique 9-membered ring moiety, together with its biosynthetic related compound 2 , were isolated from the fruits of Illicium jiadifengpi . The structure of 1 and its relative configuration were determined by spectroscopic methods and single-crystal X-ray diffraction analysis. The inhibitory rates of compound 1 on the HBeAg and HBsAg expressions were 37.91 ± 2.78% and 17.21 ± 3.78%, respectively.

Enthalpies of dilution of N,N′-hexamethylenebisacetamide in water and aqueous alkali halide solutions at the concentration of 0.150 mol⋅kg−1 (approximately the concentration of physiological saline) have been determined by isothermal titration microcalorimetry at 298.15 K. The enthalpic interaction coefficients in the solutions have been calculated according to the excess enthalpy concept based on the calorimetric data. The values of enthalpic pair-wise interaction coefficients (h 2) of the solute in aqueous solutions of different salts were discussed in terms of the different alkali salt ions and weak interactions of the diluted component with coexistent species as well as the change in solvent structure caused by ions.

Enthalpies of dilution (Δ dil H m ) of N , N ′-hexamethylenebisacetamide (HMBA) in aqueous solutions of sodium chloride (NaCl) were determined at 298.15 K by isothermal titration microcalorimetry. Densities ( ρ ) of the ternary homogeneous systems were also measured with a quartz vibrating-tube densimeter. The homogeneous enthalpic interaction coefficients have been calculated according to the excess enthalpy concept based on the calorimetric data. Apparent molar volumes ( V φ ) of the ternary systems were calculated from the data of densities, which have been used to deduce limiting partial molar volumes of HMBA ( V φ 0 ) and limiting partial molar volumes of transfer ( Δ trs V φ 0 ) from water to sodium chloride solutions at different concentrations. The results are discussed in terms of weak interactions of the diluted component with other species.

Electron transfer reaction between a simplified model molecule of α-amino carbon-centered radical and O2 has been studied with ab initio calculations at the MP2/6-31 ++ G**//UHF/6-31 ++ G** level. The reactant complex and the ion pair complex have been optimized and employed to perform calculations of the reaction heat and the reorganization energy. Solvent effects have been considered by applying the conductor-like screening model. Theoretical results show that the highly endothermic charge separation process, in which one electron transfers from the α-amino carbon-centered radical to O2, so as to form an ion pair complex, is difficult to occur in gas-phase. By applying an external electronic field to prepare the charge-localized molecular orbitals, the charge-separated state has been obtained using the initial-guess-induced self-consistent field technique. The theoretical investigations indicate that the solvent effect in the process of the oxidation of α-amino carbon-centered radical by O2 is remarkable. From the rate constant estimation, it can be predicted that the oxidation of the model donor molecule by O2 can proceed, but not very fast. A peroxyl radical compound has been found to be a competitive intermediate in the oxidation process.

As a successive work of our previous paper,1 the electron transfer matrix element (Vrp) in the oxidation of the simplified model molecule of α-amino carbon-centered radical by O2 has been investigated with ab initio calculation at the level of UHF/6-31 + + G*. Based on the optimized geometries of the reactant and the ion-pair complex obtained previously, the reaction heat and the inner reorganization energy have been obtained by constructing the potential energy curves of reactant and product states considering the solvent effect with the conductor-like screening model (COSMO). The solvent reorganization energy has been estimated using Lippert-Mataga relationship. The calculated results show that the value of Vrp, is several times larger than that of RT, which means that the model reaction is an adiabatic one. Theoretical investigation indicates that the solvent effect on the direct electron transfer (ET) process of oxidation of α-amino carbon-centered radical by oxygen is remarkable.

Haspin is a serine/threonine kinase required for completion of normal mitosis that is highly expressed during cell proliferation, including in a number of neoplasms. Consequently, it has emerged as a potential therapeutic target in oncology. A high throughput screen of approximately 140,000 compounds identified an acridine analog as a potent haspin kinase inhibitor. Profiling against a panel of 270 kinases revealed that the compound also exhibited potent inhibitory activity for DYRK2, another serine/threonine kinase. An optimization study of the acridine series revealed that the structure–activity relationship (SAR) of the acridine series for haspin and DYRK2 inhibition had many similarities. However, several structural differences were noted that allowed generation of a potent haspin kinase inhibitor (33, IC50

Three new secoiridoid glycoside dimers named swerilactosides A-C (1-3) were isolated from Swertia mileensis. Their structures were elucidated based on extensive spectral analyses (1D and 2D NMR, MS, and IR spectroscopic means).

The interactions of neutral and charged (−2, −1, +1, and +2) Ti n clusters ( n = 1–7) with one N 2 molecule were investigated by density functional theory. For neutral Ti n N 2 clusters, the nitrogen molecule is geometrically dissociative and each separated N atoms is favored to bind at the threefold hollow site for n ⩾ 3. The adsorption energies of neutral Ti n N 2 clusters which increase monotonously from n = 1 to 4 and then oscillate from n = 4 to 7, are all energetically favorable, suggesting the higher stability of large-sized neutral Ti n N 2 clusters. The detachment of Ti x (1 ⩽ x ⩽ n − 1, n = 2–7) sub-unit from neutral Ti n N 2 ( n = 2–7) clusters are energetically unfavorable, further suggesting their thermodynamic stability. The addition of different charges (−2, −1, +1, +2) on the most stable neutral Ti n N 2 ( n = 1–7) clusters would induce their geometrical perturbations. The stabilities of neutral Ti n N 2 systems are enhanced by adding −1 e , while would be reduced by −2, +1, and +2 e . The calculated adsorption energies of charged Ti n N 2 clusters have the following order: Ti n N 2 2 + > Ti n N 2 1 + > Ti n N 2 2 - > Ti n N 2 1 - .