In this work we use the newly reported boron-to-carbon ratio (B/C) from AMS-02 and the time-dependent proton fluxes from PAMELA and AMS-02 to constrain the source and propagation parameters of cosmic ...rays in the Milky Way. A linear correlation of the solar modulation parameter with solar activities is assumed to account for the time-varying cosmic ray fluxes. A comprehensive set of propagation models, with or without reacceleration or convection, has been discussed and compared. We find that only the models with reacceleration can self-consistently fit both the proton and B/C data. The rigidity dependence slope of the diffusion coefficient, δ, is found to be about 0.38–0.50 for the diffusion-reacceleration models. The plain diffusion and diffusion-convection models fit the data poorly. We compare different model predictions of the positron and antiproton fluxes with the data. We find that the diffusion-reacceleration models overproduce low energy positrons, while nonreacceleration models give better fit to the data. As for antiprotons, reacceleration models tend to underpredict low energy antiproton fluxes, unless a phenomenological modification of the velocity dependence of the diffusion coefficient is applied. Our results suggest that there could be important differences of the propagation for nuclei and leptons, in either the Milky Way or the solar heliosphere.
Mangrove restoration has become a popular strategy to ensure the critical functions and economic benefits of this ecosystem. This study conducts a meta-analysis of the peer-reviewed literature on the ...outcomes of mangrove restoration. On aggregate, restored mangroves provide higher ecosystem functions than unvegetated tidal flats but lower than natural mangrove stands (respectively RR' = 0.43, 95%CIs = 0.23 to 0.63; RR' = -0.21, 95%CIs = -0.34 to -0.08), while they perform on par with naturally-regenerated mangroves and degraded mangroves. However, restoration outcomes vary widely between functions and comparative bases, and are mediated by factors such as restoration age, species, and restoration method. Furthermore, mangrove restoration offers positive benefit-cost ratios ranging from 10.50 to 6.83 under variable discount rates (-2% to 8%), suggesting that mangrove restoration is a cost-effective form of ecosystem management. Overall, the results suggest that mangrove restoration has substantial potential to contribute to multiple policy objectives related to biodiversity conservation, climate change mitigation and sustainable development.
Triangulene and its higher homologues are a class of zigzag‐edged triangular graphene molecules (ZTGMs) with high‐spin ground states. These open‐shell molecules are predicted to host ...ferromagnetically coupled edge states with net spin values scaling with molecular size and are therefore considered promising candidates for future molecular spintronics applications. Unfortunately, the synthesis of unsubstituted ntriangulenes and the direct observation of their edge states have been a long‐standing challenge due to a high reactivity towards oxygen. However, recent advances in precursor design enabled the on‐surface synthesis and characterization of unsubstituted 3‐, 4‐, and 5triangulene. In this Minireview, we will highlight key aspects of this rapidly developing field, ranging from the principles of precursor design to synthetic strategies and characterization of a homologous series of triangulene molecules synthesized on‐surface. We will also discuss challenges and future directions.
Triangular momentum: Synthesis and characterization of the ntriangulene series (n=3–5) are presented. These open‐shell molecules are predicted to host ferromagnetically coupled edge states with net spin values scaling with molecular size and are therefore considered promising candidates for future molecular spintronics applications.
Abstract
SDSS J111215.82+111745.0 is the second pulsating extremely low-mass white dwarf discovered. Two short-period pulsations, 107.56 and 134.275 s, were detected on this star, which would be the ...first observed pressure mode (
p
-mode) pulsations observed on a white dwarf. While the two potential
p
-modes have yet to be confirmed, they make SDSS J111215.82+111745.0 an interesting object. In this work, we analyzed the whole set of seven periods observed on SDSS J111215.82+111745.0. We adopt three independent period-spacing tests to reveal a roughly 93.4 s mean period spacing of
ℓ
= 1
g
-modes, which gives added credence to the
ℓ
= 1 identifications. Then we perform asteroseismic modeling for this star, in which the H chemical profile is taken as a variable. The stellar parameters
M
= 0.1650 ± 0.0137
M
☉
and
T
eff
= 9750 ± 560 K are determined from the best-fit model, and the H/He chemical profiles are also defined. The two suspected
p
-modes are also well represented in the best-fit model, and both the stellar parameters and the pulsation frequencies are in good agreement with the values derived from spectroscopy.
Suppressing nucleation over large areas
Although formamidinium-based lead iodide (PbI
2
) perovskites have a favorable bandgap and good thermal stability, the difficulty in controlling nucleation ...makes it difficult to grow high-quality, large-area films compared with methylammonium counterparts. Bu
et al.
show that adding
N
-methyl-2-pyrrolidone to the perovskite precursors forms an adduct with PbI
2
that promotes the formation of the desired black α-phase at room temperature. The addition of potassium hexafluorophosphate eliminated hysteresis by passivating interfacial defects and promoted long-term thermal stability at 85°C in unencapsulated devices. Large-area modules (17 square centimeters) achieved power conversion efficiencies of 20.4%.
Science
, abh1035, this issue p.
1327
Added
N
-methylpyrrolidone inhibits nucleation and enables growth of large-area α-phase formamidinium-based perovskite films.
Upscaling efficient and stable perovskite layers is one of the most challenging issues in the commercialization of perovskite solar cells. Here, a lead halide–templated crystallization strategy is developed for printing formamidinium (FA)–cesium (Cs) lead triiodide perovskite films. High-quality large-area films are achieved through controlled nucleation and growth of a lead halide•
N
-methyl-2-pyrrolidone adduct that can react in situ with embedded FAI/CsI to directly form α-phase perovskite, sidestepping the phase transformation from δ-phase. A nonencapsulated device with 23% efficiency and excellent long-term thermal stability (at 85°C) in ambient air (~80% efficiency retention after 500 hours) is achieved with further addition of potassium hexafluorophosphate. The slot die–printed minimodules achieve champion efficiencies of 20.42% (certified efficiency 19.3%) and 19.54% with an active area of 17.1 and 65.0 square centimeters, respectively.
Abstract
Ultra-wide bandgap semiconductor Ga
2
O
3
based electronic devices are expected to perform beyond wide bandgap counterparts GaN and SiC. However, the reported power figure-of-merit hardly ...can exceed, which is far below the projected Ga
2
O
3
material limit. Major obstacles are high breakdown voltage requires low doping material and PN junction termination, contradicting with low specific on-resistance and simultaneous achieving of n- and p-type doping, respectively. In this work, we demonstrate that Ga
2
O
3
heterojunction PN diodes can overcome above challenges. By implementing the holes injection in the Ga
2
O
3
, bipolar transport can induce conductivity modulation and low resistance in a low doping Ga
2
O
3
material. Therefore, breakdown voltage of 8.32 kV, specific on-resistance of 5.24 mΩ⋅cm
2
, power figure-of-merit of 13.2 GW/cm
2
, and turn-on voltage of 1.8 V are achieved. The power figure-of-merit value surpasses the 1-D unipolar limit of GaN and SiC. Those Ga
2
O
3
power diodes demonstrate their great potential for next-generation power electronics applications.
Tumor metastasis is responsible for 90% of all cancer‐related deaths. Epithelial to mesenchymal transition (EMT) is an important prerequisite for tumor metastasis. One of the important mediators of ...EMT and cancer progression in ovarian cancer is the vimentin protein. The objective of the current study was to evaluate the molecular mechanism that regulates vimentin expression in ovarian cancer cells. Vimentin was robustly induced in the ovarian cancer cell line SKOV‐3 compared to normal ovarian epithelial cell line Moody and the induction was not due to transcriptional upregulation. Treatment with the proteasomal inhibitor MG‐132 revealed that vimentin is actively degraded by the proteasome in Moody cells and stabilized in the SKOV‐3 cell line. Mass spectrometric analysis of vimentin immunoprecipitate of MG‐132 treated Moody cells revealed candidate ubiquitin ligases associated with vimentin. RNAi mediated silencing of the candidate ubiquitin in Moody cells and concurrent overexpression of the candidate ubiquitin ligases in SKOV‐3 confirmed that TRIM56 is the ubiquitin ligase that is degrading vimentin in Moody cells. RNAi mediated silencing of TRIM56 in Moody cells and ectopic overexpression of TRIM56 in SKOV‐3 cells, respectively, significantly up‐ and down‐regulated in vitro migration and invasion in these cells. Analysis of TRIM56 transcript level and vimentin protein expression in 25 patients with ovarian carcinoma confirmed an inverse correlation between TRIM56 and vimentin expression. Cumulatively, our data reveals for the first time a novel post‐translational regulatory mechanism of regulating vimentin expression, EMT, and metastatic progression in ovarian cancer cells.
RNAi mediated silencing of TRIM56 in Moody cells and ectopic overexpression of TRIM56 in SKOV‐3 cells, respectively, significantly up‐ and down‐regulated in vitro migration and invasion in these cells. Analysis of TRIM56 transcript level and vimentin protein expression in 25 patients with ovarian carcinoma confirmed an inverse correlation between TRIM56 and vimentin expression.
Background
As environmental issues become increasingly prominent, the implementation of the low-carbon mode has become the trend of future economic development. The implementation of a low-carbon ...mode in the tourism industry is conducive to the sustainable development of the industry, but at present the low-carbon development of China’s tourism industry still faces many problems, especially in ethnic areas where tourism is more developed.
Results
Taking Guizhou ethnic areas as an example, this study estimated the carbon emissions of the Guizhou tourism industry from 2011 to 2015. It was found from the calculation of tourism consumption stripping coefficient that the total carbon emissions in 2011–2015 were 21.37, 25.43, 27.93, 29.51, and 30.03 million tons, showing a rapid growth trend, in which the tourism accommodation catering industry accounted for a high proportion.
Conclusions
Guizhou’s carbon emissions are increasing year by year, and there are still many problems in realizing low-carbon tourism. The low-carbon tourism mode needs to be established from aspects of government, tourism enterprises, and tourists. The rich tourism resources in minority areas should be fully utilized to realize the sustainable development of the tourism industry.
More than 60% of nonsmall cell lung cancer (NSCLC) patients show a positive response to the first ALK inhibitor, crizotinib, which has been used as the standard treatment for newly diagnosed patients ...with ALK rearrangement. However, most patients inevitably develop crizotinib resistance due to acquired secondary mutations in the ALK kinase domain, such as the gatekeeper mutation L1196M and the most refractory mutation, G1202R. Here, we develop XMU‐MP‐5 as a new‐generation ALK inhibitor to overcome crizotinib resistance mutations, including L1196M and G1202R. XMU‐MP‐5 blocks ALK signaling pathways and inhibits the proliferation of cells harboring either wild‐type or mutant EML4‐ALK in vitro and suppresses tumor growth in xenograft mouse models in vivo. Structural analysis provides insights into the mode of action of XMU‐MP‐5. In addition, XMU‐MP‐5 induces significant regression of lung tumors in two genetically engineered mouse (GEM) models, further demonstrating its pharmacological efficacy and potential for clinical application. These preclinical data support XMU‐MP‐5 as a novel selective ALK inhibitor with high potency and selectivity. XMU‐MP‐5 holds great promise as a new therapeutic against clinically relevant secondary ALK mutations.
Synopsis
Despite the clinical success of ALK inhibitors in NSCLC, multiple drug‐resistant mutations in ALK are inevitably reported. XMU‐MP‐5 overcomes resistance to first and second generation ALK inhibitors in vitro and in vivo, thus holds great promise for the therapeutic use against ALK‐positive NSCLC.
XMU‐MP‐5 is a new ALK inhibitor with high potency and selectivity.
XMU‐MP‐5 overcomes acquired resistance to first and second generation ALK inhibitors, including ALKL1196M and ALKG1202R.
XMU‐MP‐5 induces significant regression of lung tumors in ALK wild‐type and L1196M GEM models.
Despite the clinical success of ALK inhibitors in NSCLC, multiple drug‐resistant mutations in ALK are inevitably reported. XMU‐MP‐5 overcomes resistance to first and second generation ALK inhibitors in vitro and in vivo, thus holds great promise for the therapeutic use against ALK‐positive NSCLC.
Radiative energy losses are very important in regulating the cosmic ray electron and/or positron (CRE) spectrum during their propagation in the Milky Way. Particularly, the Klein–Nishina (KN) effect ...of the inverse Compton scattering (ICS) results in less efficient energy losses of high-energy electrons, which is expected to leave imprints on the propagated electron spectrum. It has been proposed that the hardening of CRE spectra around 50 GeV observed by Fermi-LAT, AMS-02, and DAMPE could be due to the KN effect. We show in this work that the transition from the Thomson regime to the KN regime of the ICS is actually quite smooth compared with the approximate treatment adopted in some previous works. As a result, the observed spectral hardening of CREs cannot be explained by the KN effect. It means that an additional hardening of the primary electrons spectrum is needed. We also provide a parameterized form for the accurate calculation of the ICS energy-loss rate in a wide energy range.
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