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The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the DArk Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of $4.3\sigma$. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out., Comment: 11 pages, 13 figures, published in Phys. Rev. Lett. Add one more digit for first three columns in Table S2

DAMPE satellite has directly measured the cosmic ray proton spectrum from 40 GeV to 100 TeV and revealed a new feature at about 13.6 TeV., The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

Principal components analysis (PCA) is a data analysis and reduction technique widely used in the method of statistical analysis,elucidation of the variation of five mechanical properties (tensile strength, bending strength, impact strength, tensile modulus and bending modulus) and five microstructure properties (carbonyl index, hydroxyl index, branching degree, chain scission degree and unsaturated value) that taken place when subjected to ultraviolet (UV) aging of high density polyethylene (HDPE) used as rotational packaging case by using PCA. The information of main components were extracted and studied. Also the relationships between performance properties were considered. Finally, the combined evaluating parameter Z was established and analyzed. The results show that the first and second components extracted by PCA can be determined on behalf of all components. Among the 10 performance parameters, tensile strength, bending strength and impact strength are strongly correlated, carbonyl index, hydroxyl index, branching degree and chain scission degree are strongly correlated, and the tensile modulus is non-correlated to other performance parameters. The trendy of the evaluating parameter Z show that the HDPE aged quickly in the first 20 days and leveled off in the following days.

To evaluate the aging behavior of high density polyethylene (HDPE) under an artificial accelerated environment, principal component analysis (PCA) was used to establish a non-dimensional expression Z from a data set of multiple degradation parameters of HDPE. In this study, HDPE samples were exposed to the accelerated thermal oxidative environment for different time intervals up to 64 days. The results showed that the combined evaluating parameter Z was characterized by three-stage changes. The combined evaluating parameter Z increased quickly in the first 16 days of exposure and then leveled off. After 40 days, it began to increase again. Among the 10 degradation parameters, branching degree, carbonyl index and hydroxyl index are strongly associated. The tensile modulus is highly correlated with the impact strength. The tensile strength, tensile modulus and impact strength are negatively correlated with the crystallinity.

Positron annihilation lifetime (PAL) spectroscopy is a powerful tool to study atomic-scaled microstructure of materials. But PAL spectra can be easily distorted, then one will get wrong conclusions. Conventional PAL spectrometers have been widely used but the data processing capability is limited. In order to deal with the generally existed problems related to spectra distortion, and find an economic way to let conventional PAL spectrometers have better performance, we design a reconfigurable PAL spectrometer based on conventional electronic system, multi-channel digitizer card, and LaBr 3 scintillator. By using several data processing methods, analysis results of PAL spectra show significant improvements. We discuss the reasons that cause PAL spectra distortion, and try to figure out how our methods can bring changes. Related works including PAL spectra simulation and Geant4 energy deposition simulation have been done. Several other functions such as time walk offset have been developed to improve the performance of whole system. The spectrometer is still capable to add more functions if needed.

Recent detections of g-mode pulsations in subdwarf B (sdB) stars from the space missions CoRoT and Kepler have verified that nearly all of these pulsators have regular period spacings. This discovery has been extensively applied to mode identification for the observed g-mode sdB pulsators. However, the discovery of regular period spacings apparently contradicts the strong g-mode trapping structure expected in canonical sdB models, which is caused by steep chemical gradients in such evolved stars. Although the mode trapping efficiency could be reduced somewhat by taking into account the diffusion effect during the sdB phase, it is still difficult to explain the regular period spacings of g-mode sdB pulsators, especially in the short-period range. We suggest that the regular period spacings may arise earlier in the evolution of sdB stars rather than during the sdB stage itself. As for a canonical sdB star, it is evolved from a low-mass star and is considered to have gone through the He flash. The He flash causes extensive and aggressive convection that extends very close to the He/H transition zone. When considering a proper convective overshoot during the He-flash stage, the chemical profile in the He/H transition zone becomes smoother. Detailed model calculations show that the mode trapping efficiency could be reduced to approximately the level of observations throughout the observed period range by taking the He-flash overshoot into account.

Elucidation of the chemical structure changes that take place of high density polyethylene (HDPE) used as rotational packaging case by attenuated total reflection infrared spectroscopy (ATR-FTIR), when natural aging of Lasa Tibet and xenon aging. The variations of carbonyl index (CI), hydroxyl index (HI), branching degree (N) and crystallinity (Xc) have been studied from qualitative and quantitative. Finally, the correlations between natural and xenon aging have been closely followed. It found that the oxidation and growth of unsaturated compounds play a leading role in the natural aging progress, but the polymeric chain scission is weak effect. However, the samples show a slower growth of unsaturated compounds and a sharp increase in polymeric chain scission after xenon aging. The CI, HI and N increased generally in a line fashion after natural and xenon aging while the Xc changes little.

Vitamin D (VD) has exhibited immunomodulatory role in the pathogenesis of preeclampsia. We hypothesize VD potentiate nifedipine treatment for preeclampsia by shortened the time to control blood pressure and prolong time before subsequent hypertensive crisis. We conduct a randomized trial of 683 primigravid women with preeclampsia, who were assigned to different treatment groups, either nifedipine+placebo or nifedipine+VD orally, by random after screening. Primary endpoints include time to control hypertension and time before another hypertensive crisis. Maternal adverse effects including nausea, vomiting, chest pain, mild headache, dizziness, maternal tachycardia, hypotension or shortness of breath, and neonatal parameters including birth weight and Apgar scores, as well as the minimum number of dosages needed to control hypertension were defined as secondary endpoints. Serum levels of cytokines tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were also examined. There was a marked reduction of the time required to control hypertension and a significant lengthening (p = 0.013) of the time before a new hypertensive crisis in participants received nifedipine+VD treatments (41.8 ± 18.3 min), in comparison with the nifedipine+placebo controls (61.1 ± 15.9 min). In women treated with nifedipine+VD, the minimum number of dosages needed to control hypertension was also lower. With regard to adverse effects, no statistical difference was observed between the two treatment groups. Moreover, treatment with VD increased IL-10 and reduced TNF-α serum levels. VD possesses the potential of serving as a safe and effective adjuvant to oral nifedipine in treating women with preeclampsia against hypertension, possibly through the upregulation of IL-10 and the downregulation of TNF-α.

High energy cosmic ray electrons plus positrons (CREs), which lose energy quickly during their propagation, provide an ideal probe of Galactic high-energy processes and may enable the observation of phenomena such as dark-matter particle annihilation or decay. The CRE spectrum has been directly measured up to $\sim 2$ TeV in previous balloon- or space-borne experiments, and indirectly up to $\sim 5$ TeV by ground-based Cherenkov $\gamma$-ray telescope arrays. Evidence for a spectral break in the TeV energy range has been provided by indirect measurements of H.E.S.S., although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range $25~{\rm GeV}-4.6~{\rm TeV}$ by the DArk Matter Particle Explorer (DAMPE) with unprecedentedly high energy resolution and low background. The majority of the spectrum can be properly fitted by a smoothly broken power-law model rather than a single power-law model. The direct detection of a spectral break at $E \sim0.9$ TeV confirms the evidence found by H.E.S.S., clarifies the behavior of the CRE spectrum at energies above 1 TeV and sheds light on the physical origin of the sub-TeV CREs., Comment: 18 pages, 6 figures, Nature in press, doi:10.1038/nature24475

Based on regularities in rotational splittings, we seek possible multiplets for the observed frequencies of CoRoT 102749568. Twenty-one sets of multiplets are identified, including four sets of multiplets with $l=1$, nine sets of multiplets with $l=2$, and eight sets of multiplets with $l=3$. In particular, there are three complete triplets ($f_{10}$, $f_{12}$, $f_{14}$), ($f_{31}$, $f_{34}$, $f_{35}$), and ($f_{41}$, $f_{43}$, $f_{44}$). The rotational period of CoRoT 102749568 is estimated to be $1.34^{+0.04}_{-0.05}$ days. When doing model fittings, three $l=1$ modes ($f_{12}$, $f_{34}$, and $f_{43}$) and the radial first overtone $f_{13}$ are used. Our results shows that the three nonradial modes ($f_{12}$, $f_{34}$, and $f_{43}$) are mixed modes, which mainly provide constraints on the helium core. The radial first overtone $f_{13}$ mainly provides constraint on the stellar envelope. Hence the size of the helium core of CoRoT 102749568 is determined to be $M_{\rm He}$ = 0.148 $\pm$ 0.003 $M_{\odot}$ and $R_{\rm He}$ = 0.0581 $\pm$ 0.0007 $R_{\odot}$. The fundamental parameters of CoRoT 102749568 are determined to be $M$ = 1.54 $\pm$ 0.03 $M_{\odot}$, $Z=$ 0.006, $f_{\rm ov}$ = 0.004 $\pm$ 0.002, $\log g$ = 3.696 $\pm$ 0.003, $T_{\rm eff}$ = 6886 $\pm$ 70 K, $R$ = 2.916 $\pm$ 0.039 $R_{\odot}$, and $L$ = 17.12 $\pm$ 1.13 $L_{\odot}$., The paper is accepted for publication in The Astrophysical Journal. 5 figures and 8 Tables

In this paper we report the results of Micromegas prototypes constructed by attaching micromesh to an anode using thermo-bond films. The excellent metal attaching ability and good dielectical property of this kind of film make it a promising material to be used as avalanche gap spacers. Several prototypes are successfully made. The electron transmission properties are first studied and then the gas gain is measured in argon-isobutane mixtures. The maximum gain of more than 104 is easily obtained. The energy resolutions for 55Fe 5.9 keV Kα ray can be better than 20% over one magnitude in gain for different operational gas mixtures and the best energy resolution of 13.7% (FWHM) can be achieved with the gas mixture of 94% argon concentration. The preliminary test results of the prototypes with sensitive area of 45 mm×45 mm without internal support show good uniformity across the sensitive area.

Subdwarf B stars are generally considered to be core helium-burning stars. However, most canonical sdB models have shown that they leave the sdB band (i.e., the region with 20,000 K ≤ T eff ≤ 40,000 K and ) after they have ignited helium in the shell. This means there will be a few shell helium-burning stars that have exhausted their helium in the core yet may still be located on the sdB band and should be considered as sdB stars too. But because they have effective temperature and gravity close to those of core helium-burning sdB stars, we cannot distinguish the two kinds of star just by atmospheric parameters. Some sdB stars display multimode pulsations. We thought that asteroseismology could offer some methods to distinguish the two kinds of sdB star. Core and shell helium-burning sdB stars have some obvious differences in structure and evolutionary track, which results in some clear differences in their pulsation properties. So, we may distinguish them by their pulsation properties such as the rates of change of period of the p-mode sdB pulsators, the numbers of mixed modes, and the period spacings of the g-mode sdB pulsators. We suggest that there are two special sdB stars (V391 Pegasi and PG 1605+072) that are likely shell helium-burning sdB stars.

Mixing in the convective core is quite uncertain in core helium burning stars. In order to explore the overshooting mixing beyond the convective core, we incorporated the $k$-$\omega$ proposed by Li (2012, 2017) into MESA, and investigated the overshooting mixing in evolution of sdB models. We found that the development of the convective core can be divided into three stages. When the radiative temperature gradient $\nabla_{\rm rad}$ monotonically decreases from the stellar center, the overshooting mixing presents a behaviour of exponential decay similar with Herwig (2000), and the overshooting distance is to make $\nabla_{\rm rad} \simeq \nabla_{\rm ad}$ at the boundary of the convective core, in agreement with the prediction of the self-driving mechanism Castellani, Giannone \& Renzini (1971a). When the radiative temperature gradient $\nabla_{\rm rad}$ shows a minimum value in the convective core, the convective core may be divided into two convection zones if the minimum value of $\nabla_{\rm rad}$ is smaller than the adiabatic temperature gradient $\nabla_{\rm ad}$. For the single-zone case, the overshooting mixing still shows an exponential decay behaviour, but the overshooting distance is much smaller than in the initial stage. For the double-zone case, the overshooting mixing is similar to that of the single-case beyond the convective core, while it almost stops on both sides of the above convective shell. Our overshooting mixing scheme is similar to the maximal overshoot scheme of Constantino et al. (2015). In the final stage, continuous injection of fresh helium into the convective core by the overshooting mixing happens, which is similar to the "core breathing pulses" (Sweigart \& Demarque 1973; Castellani et al. 1985)., Comment: accepted by ApJ

Introduction and aim. Matrix metalloproteinase (MMP)-2 and MMP-9 are reported to participate in several pregnancy-related diseases, including intrahepatic cholestasis of pregnancy (ICP), which is a severe liver disorder in pregnant women. Meanwhile, ample evidences have demonstrated that celastrol inhibits the activity and expression of MMPs. The present study aims to examine the effect of celastrol to alleviate symptoms of ICP in rat model. Material and methods. By inducing ICP with 17 - ethinylestradiol in pregnant female rats, we assessed the impact of celastrol administration on symptoms of ICP, such as the rate of bile flow, the level of total bile acids (TBA), and the activities of MMP-2 and -9. Furthermore, the correlations between the levels of MMPs with the examined ICP symptoms were investigated. Results. In rats with ICP, both MMP-2 and -9 exhibited significantly elevated activities, which were inhibited by the administration of celastrol. Furthermore, ICP symptoms such as bile flow rate and total TBA were restored by celastrol. Lastly, there were strong correlations between levels of the two MMPs and TBA. Conclusion. Our findings described for the first time the effects of celastrol to attenuate ICP symptoms through an inhibition of both MMP-2 and -9, providing evidence for a potential role of celastrol as a new drug for the treatment of ICP.

Multi-gap Resistive Plate Chambers (MRPCs) were selected to construct the barrel Time of Flight (TOF) detector for the STAR experiments. Its mass production started in 2006. The production procedure and related quality control (QC) are described. A summary of the MRPC production status (2006–2008) and the test results with cosmic rays is given. With strict QC throughout the production process, over 95 % of the constructed MRPC modules meet the criteria required by STAR experiments.

High density polyethylene (HDPE) was widely used as rotational packaging case in the material reserve field. The chemical changes of HDPE, exposed to particular climatic conditions of tropic marine atmosphere for one year-long in Wanning Hainan, were elucidated by the attenuated total reflection infrared spectroscopy (ATR-FTIR). The structural changes were studied qualitatively, mainly from the polymeric chain breaking, branching and oxidation to distinguish the degradation profile. The variations of crystallinitycarbonyl index were also studied quantitatively according to the characteristic peaks intensityarea ratio. Finally, the relationships between structural changes and mechanical properties were investigated. The results showed that the polymeric chain breakingbranching play a leading role before 3 months in the aging progress. Then oxidation phenomena gradually takes place during 3-6 months. The chain branchingoxidation were predominant factors after 6 months. Nine months later, the oxidation was saturated gradually. Furthermore, the aging process is positively correlated to the temperature and irradiation. After 12 months aging, the carbonyl index increased by 112 times and crystallinity was 10% higher than before. The tensile/bending modulus deceased faster than tensile/bending strength of HDPE. The linear degree of tensile modulus and carbonyl index was 0.97. The degree of linearity of tensile strength and crystallinity calculated by feature bands (720-730 cm(-1)) was 0.96. It showed that the mechanical properties of HDPE can be speculated from the structural changes by ATR-FTIR.

We report simulation results of the Micromegas in a bulk and PIM (parallel ionization multiplier) with one or more layers of woven micromeshes based on 3D models and Garfield/ Magboltz. Studies are conducted for different detector geometries. Effects of wire diameter, mesh pitch, mesh effective thickness and gas mixture are investigated. The transverse diffusion of drifting electrons and broadening of electron clouds that affect electron transfer through the micromeshes are studied. Different arrangements of gas gains in the required avalanche and signal induction regions of a PIM-like configuration are studied. The motivation of this work is to understand the electron transfer process in Micromegas and PIMs constructed by using relatively thick woven micromeshes. We have attempted to find optimized PIM configurations in order to obtain high gas gain, fast rise time and other desirable detector properties.

Anginex is a novel artificial peptide that can inhibit angiogenesis. AdNT4-anginex was constructed by inserting the artificial anginex gene into a recombinant adenoviral vector. We demonstrated that AdNT4-anginex inhibited migration of human endothelial cells, angiogenesis and tumor growth in in vitro and in vivo studies. Tumor growth of human H22 hepatoma in mice was inhibited after AdNT4-anginex treatment for 4 weeks, and a significant decrease in tumor size was observed as compared with the control group. Overall, these studies indicate that AdNT4-anginex is an effective anti-tumor agent, and deserves more attention and research.

To investigate the relationship among the serum vascular endothelial growth factor C (sVEGF-C), expression of cyclooxygenase 2 (COX-2), and lymph vessel density (LMVD), and to discuss their role in tumor progression and lymphatic metastasis.sVEGF-C level was detected by ELISA in 68 pre-operation breast cancer patients, 35 breast benign disease patients, and 12 healthy women. Immunohistochemical method was used to detect the expression of COX-2 and lymphatic vessel endothelial hyaluronidase receptor (LYVE)-1 in the breast cancer tissues and benign disease tissues obtained during operation.(1) The sVEGF-C level of the pre-operation breast cancer group was (49 +/- 8) pg/ml, significantly higher than those of the begin tumor group [(8 +/- 4) pg/ml, P = 0.045] and the healthy women [(5 +/- 3) pg/ml, P = 0.003]. (2) The COX-2 overexpression positive rate in the breast cancer tissues was 44.1%, significantly higher than that in the begin disease tissues (11.4%, P = 0.002). Higher than that in the begin disease tissue; the LMVD overexpression in the breast cancer tissues was mainly located in the para-carcinoma tissue (8.7 +/- 4.7), significantly higher than that in the begin disease tissues (1.8 +/- 1.7, P = 0.002). (3) The COX-2 overexpression rate of the patients with a high sVEGF-C level was significantly higher than that of the patients with a low sVEGF-C level (P = 0.024). The LMVD level in the breast cancer of the sVEGF-C high level group was (8.7 +/- 3.9), significantly higher than that of the sVEGF-C normal group (5.6 +/- 3.3, P = 0.039). (4) The LMVD in the COX-2 overexpression breast cancer group was 9.5 +/- 3.7, significantly higher than that in the COX-2 negative group (6.0 +/- 3.8, P = 0.012). (5) The sVEGF-C level, COX-2, and LMVD expression in the breast cancer patients with lymphatic metastasis were significantly higher than those in the patients without lymphatic metastasis (P = 0.025, 0.022, and 0.002 respectively).VEGF-C, COX-2, and LMVD play important roles in the lymphatic metastasis of breast cancer. They may be important prognostic factors in evaluating breast cancer lymphatic metastasis.

To investigate the relationship between serum VEGF (sVEGF) level and VEGF, COX-2 and MVD expression in breast cancer, and to discuss their role in angiogensis of breast cancer.sVEGF level was detected by ELISA in 68 preoperative breast cancer, 35 benign breast disease and 20 healthy women. The expression of VEGF, COX-2 and MVD was detected by immunohistochemical method in tissues of breast cancer and breast benign diseases, and to analyze the relationship of sVEGF, VEGF, COX-2 and MVD.(1) sVEGF level in preoperative breast cancers was 306.51 pg/ml (interquartile range from 190.44 to 442.04 pg/ml), in benign diseases was 150.82 pg/ml (interquartile range from 82.36 to 212.34 pg/ml), and in healthy control was 105.93 pg/ml (interquartile range from 78.54 to 157.77 pg/ml). The sVEGF level of preoperative breast cancer group was significantly higher than that of breast benign disease group and healthy women (P = 0.001). (2) The VEGF expression positive rate in breast cancer (67.65%) was significantly higher than that in breast benign disease (44.12%) (P = 0.015). The COX-2 expression positive rate in breast cancer (42.86%) was significantly higher than that in breast benign disease (11.43%) (P = 0.002). (3) the COX-2 expression positive rate in sVEGF high level patients (56.00%) was significantly higher than that in sVEGF normal level patients (11.11%) (P = 0.024), and MVD in sVEGF high level patients (27.32 +/- 3.40) was also higher than that in sVEGF normal level patients (15.31 +/- 6.16) (P = 0.011). (4) The sVEGF level (322.09 +/- 79.31) of 68 breast cancer patients whose VEGF was positive in breast cancer tissues was significantly higher than that in VEGF negative group (222.47 +/- 73.53) (P = 0.017). (5) The COX-2 expression positive rate in VEGF positive expression group (65.21%) was significantly higher than that in VEGF negative expression group (18.18%) (P = 0.017). The MVD expression in COX-2 positive expression group (22.94 +/- 5.51) was significantly higher than that in COX-2 negative expression group (10.30 +/- 4.42) (P = 0.027).sVEGF level in breast cancer is significantly higher than that in breast benign disease and healthy women, and is correlated with the expression of COX-2 and MVD in breast cancer tissues.