We introduce a new generation of PARSEC-COLIBRI stellar isochrones that include a detailed treatment of the thermally-pulsing asymptotic giant branch (TP-AGB) phase, and covering a wide range of initial metallicities (0.0001 < Z i < 0.06). Compared to previous releases, the main novelties and improvements are: use of new TP-AGB tracks and related atmosphere models and spectra for M and C-type stars; inclusion of the surface H+He+CNO abundances in the isochrone tables, accounting for the effects of diffusion, dredge-up episodes and hot-bottom burning; inclusion of complete thermal pulse cycles, with a complete description of the in-cycle changes in the stellar parameters; new pulsation models to describe the long-period variability in the fundamental and first overtone modes; new dust models that follow the growth of the grains during the AGB evolution, in combination with radiative transfer calculations for the reprocessing of the photospheric emission. Overall, these improvements are expected to lead to a more consistent and detailed description of properties of TP-AGB stars expected in resolved stellar populations, especially in regard to their mean photometric properties from optical to mid-infrared wavelengths. We illustrate the expected numbers of TP-AGB stars of different types in stellar populations covering a wide range of ages and initial metallicities, providing further details on the "C-star island" that appears at intermediate values of age and metallicity, and about the AGB-boosting effect that occurs at ages close to 1.6-Gyr for populations of all metallicities. The isochrones are available through a new dedicated web server.

Many stellar models present difficulties in reproducing basic observational relations of very low mass stars (VLMS), including the mass-radius relation and the optical colour-magnitudes of cool dwarfs. Here, we improve PARSEC models on these points. We implement the T -τ relations from PHOENIX BT-Settl model atmospheres as the outer boundary conditions in the PARSEC code, finding that this change alone reduces the discrepancy in the mass-radius relation from 8 to 5 per cent. We compare the models with multi-band photometry of clusters Praesepe and M 67, showing that the use of T -τ relations clearly improves the description of the optical colours and magnitudes. But anyway, using both Kurucz and PHOENIX model spectra, model colours are still systematically fainter and bluer than the observations. We then apply a shift to the above T -τ relations, increasing from 0 at T eff = 4730 K to ∼14% at T eff = 3160 K, to reproduce the observed mass-radius radius relation of dwarf stars. Taking this experiment as a calibration of the T -τ relations, we can reproduce the optical and near infrared CMDs of low mass stars in the old metal-poor globular clusters NGC 6397 and 47 Tuc, and in the intermediate-age and young solar-metallicity open clusters M 67 and Praesepe. Thus, we extend PARSEC models using this calibration, providing VLMS models more suitable for the lower main sequence stars over a wide range of metallicities and wavelengths. Both sets of models are available on PARSEC webpage.

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Immunoassay has been an essential tool in many areas, including clinical diagnostics. However, it suffers from drawbacks, such as poor availability of high specificity antibodies, limited stability of biological reagents, as well as damage to health and susceptibility of chemical labels to the sample environment. Here we present a new approach, a boronate-affinity sandwich assay (BASA), for the specific and sensitive determination of trace glycoproteins in complex samples. BASA relies on the formation of sandwiches between boronate-affinity molecularly imprinted polymers (MIPs), target glycoproteins, and boronate-affinity surface-enhanced Raman scattering (SERS) probes. The MIP ensures the specificity, while the SERS detection provides the sensitivity. BASA overcomes the drawbacks of traditional immunoassays and offers a great prospect for application.

Chandra observations of the Crab-like supernova remnant G21.5-0.9 reveal a compact central core and spectral variations indicative of synchrotron burn-off of higher energy electrons in the inner nebula. The central core is slightly extended, perhaps indicating the presence of an inner wind-shock nebula surrounding the pulsar. No pulsations are observed from the central region, yielding an upper limit of approximately 40% for the pulsed fraction. A faint outer shell may be the first evidence of the expanding ejecta and blast wave formed in the initial explosion, indicating a composite nature for G21.5-0.9.

3C 397 is a radio and X-ray bright Galactic supernova remnant (SNR) with an unusual rectangular morphology. Our CO observation obtained with the Purple Mountain Observatory at Delingha reveals that the remnant is well confined in a cavity of molecular gas, and embedded at the edge of a molecular cloud (MC) at the local standard of rest systemic velocity of ∼ 32 km s −1 . The cloud has a column density gradient increasing from southeast to northwest, perpendicular to the Galactic plane, in agreement with the elongation direction of the remnant. This systemic velocity places the cloud and SNR 3C 397 at a kinematic distance of ∼ 10.3 kpc. The derived mean molecular density (∼ 10-30 cm −3 ) explains the high volume emission measure of the X-ray emitting gas. A 12 CO line broadening of the ∼ 32 km s −1 component is detected at the westmost boundary of the remnant, which provides direct evidence of the SNR-MC interaction and suggests multi-component gas there with dense (∼ 10 4 cm −3 ) molecular clumps. We confirm the previous detection of a MC at ∼ 38 km s −1 to the west and south of the SNR and argue, based on HI self-absorption, that the cloud is located in the foreground of the remnant.A list of 64 Galactic SNRs presently known and suggested to be in physical contact with environmental MCs is appended in this paper.

Solution processable flexible transparent electrodes (FTEs) are urgently needed to boost the efficiency and mechanical stability of flexible organic solar cells (OSCs) on a large scale. However, how to balance the optoelectronic properties and meanwhile achieve robust mechanical behavior of FTEs is still a huge challenge. Silver nanowire (AgNW) electrodes, exhibiting easily tuned optoelectronic/mechanical properties, are attracting considerable attention, but their poor contacts at the junction site of the AgNWs increase the sheet resistance and reduce mechanical stability. In this study, an ionic liquid (IL)-type reducing agent containing Cl − and a dihydroxyl group was employed to control the reduction process of silver (Ag) in AgNW-based FTEs precisely. The Cl − in the IL regulates the Ag + concentration through the formation and dissolution of AgCl, whereas the dihydroxyl group slowly reduces the released Ag + to form metal Ag. The reduced Ag grew in situ at the junction site of the AgNWs in a twin-crystal growth mode, facilitating an atomic-level contact between the AgNWs and the reduced Ag. This enforced atomic-level contact decreased the sheet resistance, and enhanced the mechanical stability of the FTEs. As a result, the single-junction flexible OSCs based on this chemically welded FTE achieved record power conversion efficiencies of 17.52% (active area: 0.062 cm 2 ) and 15.82% (active area: 1.0 cm 2 ). These flexible devices also displayed robust bending and peeling durability even under extreme test conditions.

We present a 60 ks Chandra ACIS-S observation of the thermal composite supernova remnant 3C 391. The southeast-northwest elongated morphology is similar to that previously found in radio and X-ray studies. This observation unveils a highly clumpy structure of the remnant. Detailed spatially resolved spectral analysis for the small-scale features reveals that the interior gas is generally of normal metal abundance and has approached or basically reached ionization equilibrium. The hydrogen column density increases from southeast to northwest. Three mechanisms, radiative rim, thermal conduction, and cloudlet evaporation, may all play roles in the X-ray appearance of 3C 391 as a "thermal composite" remnant, but there are difficulties with each of them in explaining some physical properties. Comparatively, the cloudlet evaporation model is favored by the main characteristics such as the highly clumpy structure and the uniform temperature and density distribution over most of the remnant. The directly measured postshock temperature also implies a young age, ∼ 4 × 10 3 yr, for the remnant. The postshock gas pressure derived from the NE and SW rims, which harbor maser spots, is consistent with the estimate for the maser regions. An unresolved X-ray source is observed on the northwest border and its spectrum is best fitted by a power-law.