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Artificial photosynthesis, converting solar energy to renewable fuels and valuable chemicals, shows a high potential for addressing the exhaustion of fossil fuels and the greenhouse effect. The superior optoelectronic properties of metal halide perovskites (MHPs) make this emerging family of materials promising candidates for efficient solar-to-fuel conversion. However, the issue of stability has been the main obstacle for MHPs based photocatalysis. In this work, we emphasize the major bottleneck that hinders the application of MHPs for photocatalytic solar-to-fuel conversion. After outlining the unstable factors for MHPs based photocatalysis, we analyse recent works in related fields and provide a critical review of approaches to improving the stability of MHPs for the photocatalytic H2 evolution reaction and CO2 reduction reaction. We conclude by proposing possible directions for the development of stabilizing MHPs towards efficient and cost-effective solar-to-fuel conversion.

Ascorbate peroxidase (APX) plays an important role in scavenging H

Methodological choices can have strong effects on projections of climate change impacts on hydrology. In this study, we investigate the ways in which four different steps in the modeling chain influence the spread in projected changes of different aspects of hydrology. To form the basis of these analyses, we constructed an ensemble of 160 simulations from permutations of two Representative Concentration Pathways, 10 global climate models, two downscaling methods, and four hydrologic model implementations. The study is situated in the Pacific Northwest of North America, which has relevance to a diverse, multinational cast of stakeholders. We analyze the effects of each modeling decision on changes in gridded hydrologic variables of snow water equivalent and runoff, as well as streamflow at point locations. Results show that the choice of representative concentration pathway or global climate model is the driving contributor to the spread in annual streamflow volume and timing. On the other hand, hydrologic model implementation explains most of the spread in changes in low flows. Finally, by grouping the results by climate region the results have the potential to be generalized beyond the Pacific Northwest. Future hydrologic impact assessments can use these results to better tailor their modeling efforts.

Rational design of photocatalysts is essential to achieve efficient solar energy conversion. For narrow bandgap Ta3N5 photocatalyst, various charge recombination occurring in the bulk, interface and on the surface significantly impairs its activity for solar hydrogen (H2) generation. Herein, a synergistic engineering approach is designed to solve this critical recombination challenge. First, hollow spherical structure of Ta3N5 with Mg doping is prepared to not only reduce the charge migration distance and increase the surface area, but also increase the electron mobility for facilitated charge transfer. Second, an MgO nano-layer covers the surface of hollow Ta3N5 structure to passivate surface defects, thus promoting the interfacial charge transfer between Ta3N5 and co-catalysts. Finally, dual co-catalysts (Pt/CoOx) for redox reactions are loaded onto the hollow Ta3N5 structure to reduce the surface recombination and overcome the sluggish surface reaction. Remarkably, the combination of hollow structure, Mg2+ doping, MgO interfacial layer, and dual co-catalysts effectively improves the charge separation and transfer in Ta3N5 photocatalyst. This newly designed photocatalyst exhibits a considerably improved H2 generation performance of 56.3 μmol h−1 under simulated sunlight, compared to that of reference Pt/Ta3N5 hollow spheres.

Loss of TGF-β tumour suppressive response is a hallmark of human cancers. As a central player in TGF-β signal transduction, SMAD4 (also known as DPC4) is frequently mutated or deleted in gastrointestinal and pancreatic cancer. However, such genetic alterations are rare in most cancer types and the underlying mechanism for TGF-β resistance is not understood. Here we describe a mechanism of TGF-β resistance in ALK-positive tumours, including lymphoma, lung cancer and neuroblastoma. We demonstrate that, in ALK-positive tumours, ALK directly phosphorylates SMAD4 at Tyr 95. Phosphorylated SMAD4 is unable to bind to DNA and fails to elicit TGF-β gene responses and tumour suppressing responses. Chemical or genetic interference of the oncogenic ALK restores TGF-β responses in ALK-positive tumour cells. These findings reveal that SMAD4 is tyrosine-phosphorylated by an oncogenic tyrosine kinase during tumorigenesis. This suggests a mechanism by which SMAD4 is inactivated in cancers and provides guidance for targeted therapies in ALK-positive cancers. Zhang et al. show that ALK phosphorylates SMAD4 at Tyr 95 to block its binding to DNA, representing a mutation-independent mechanism for blocking the tumour suppressor function of TGF-β in ALK-positive cancers.

A deep understanding of SARS-CoV-2-host interactions is crucial to the development of effective therapeutics. The role of non-coding regions of viral RNA (ncrRNAs) has not been scrutinized. We developed a method using MS2 affinity purification coupled with liquid chromatography-mass spectrometry (MAMS) to systematically map the interactome of SARS-CoV-2 ncrRNA in different human cell lines. Integration of the results defined the core and cell-type-specific ncrRNA-host protein interactomes. The majority of ncrRNA-binding proteins were involved in RNA biogenesis, protein translation, viral infection, and stress response. The 5′ UTR interactome is enriched with proteins in the snRNP family and is a target for the regulation of viral replication and transcription. The 3′ UTR interactome is enriched with proteins involved in the cytoplasmic RNP granule (stress granule) and translation regulation. We show that the ORF10 is likely to be a part of 3′ UTR. Intriguingly, the interactions between negative-sense ncrRNAs and host proteins, such as translation initiation factors and antiviral factors, suggest a pathological role of negative-sense ncrRNAs. Moreover, the cell-type-specific interactions between ncrRNAs and mitochondria may explain the differences of cell lines in viral susceptibility. Our study unveils a comprehensive landscape of the functional SARS-CoV-2 ncrRNA-host protein interactome, providing a new perspective on virus-host interactions and the design of future therapeutics.

In B c − $$ {B}_c^{-} $$ → J/ψ(→ μ + μ − )τ − ν ¯ τ $$ {\overline{\nu}}_{\tau } $$ decay, the three-momentum p τ − $$ {\boldsymbol{p}}_{\tau^{-}} $$ cannot be determined accurately due to the decay products of τ − inevitably include an undetected ν τ . As a consequence, the angular distribution of this decay cannot be measured. In this work, we construct a measurable angular distribution by considering the subsequent decay τ − → π − ν τ . The full cascade decay is B c − $$ {B}_c^{-} $$ → J/ψ(→ μ + μ − )τ − (→ π − ν τ ) ν ¯ τ $$ {\overline{\nu}}_{\tau } $$ , in which the three-momenta p μ + , p μ − $$ {\boldsymbol{p}}_{\mu^{+}},{\boldsymbol{p}}_{\mu^{-}} $$ , and p π − $$ {\boldsymbol{p}}_{\pi^{-}} $$ can be measured. The five-fold differential angular distribution containing all Lorentz structures of the new physics (NP) effective operators can be written in terms of twelve angular observables ℐ i (q 2 , E π ). Integrating over the energy of pion E π , we construct twelve normalized angular observables ℐ ̂ i $$ {\hat{\mathrm{\mathcal{I}}}}_i $$ (q 2) and two lepton-flavor-universality ratios R P L , T J / ψ $$ R\left({P}_{L,T}^{J/\psi}\right) $$ (q 2). Based on the B c → J/ψ form factors calculated by the latest lattice QCD and sum rule, we predict the q 2 distribution of all ℐ ̂ i $$ {\hat{\mathrm{\mathcal{I}}}}_i $$ and R P L , T J / ψ $$ R\left({P}_{L,T}^{J/\psi}\right) $$ both within the Standard Model and in eight NP benchmark points. We find that the benchmark BP2 (corresponding to the hypothesis of tensor operator) has the greatest effect on all ℐ i and R P L , T J / ψ $$ R\left({P}_{L,T}^{J/\psi}\right) $$ , except ℐ ̂ 5 $$ {\hat{\mathrm{\mathcal{I}}}}_5 $$ . The ratios R P L , T J / ψ $$ R\left({P}_{L,T}^{J/\psi}\right) $$ are more sensitive to the NP with pseudo-scalar operators than the ℐ i . Finally, we discuss the symmetries in the angular observables and present a model-independent method to determine the existence of tensor operators.

The Colorado River Basin (CRB) has experienced widespread and prolonged drought in the 21st century with recent precipitation (P) up to 25% below historical means and air temperature (T) up to 0.8 oC warmer. The extent that continued warming will lead to streamflow (Q) decline is unclear given the high interannual variability of P. Here we explore physically plausible ways that climate change could impact Q using the Variable Infiltration Capacity (VIC) model. We integrated advances in VIC using Landsat- and MODIS-based products to produce more realistic land surface conditions and used this setup to simulate long-range Q projections. Meteorological datasets were sourced from gridded daily observations (1950-2013) and downscaled historical (1950-2005) and future projections (2006-2099) derived from multiple CMIP5 models under a low and a high emission scenario to explore forcing uncertainties and cases where P increase could offset warming. We compared the impacts of anticipated climate change on hydrologic responses in subbasins key for water management to gauge their importance for basin-wide water budgets and how these relationships could evolve in time, as this has been a largely unexplored aspect in the CRB. Results showed that spatial gradients in seasonal P changes led to contrasting seasonal responses in runoff (R) across the CRB. Whereas most of the Upper Basin had a shift to greater R during the winter, summer R declined over most of the CRB due to heightened evapotranspiration in the northwest (Green, Upper Colorado, Glen Canyon, and Grand Canyon subbasins) and large P decline in the southeast (San Juan, Little Colorado, and Gila subbasins). The strength of seasonal runoff signals across different climate models and their impacts to annual Q were dependent on subbasin area and emission scenario. Annual Q at the CRB outlet declined in most cases, however, reflecting the pervasive drying effect of warming.

In $B_c^- \to J/��(\to ��^+ ��^-)��^-\bar��_��$ decay, the three-momentum $\boldsymbol{p}_{��^-}$ cannot be determined accurately due to the decay products of $��^-$ inevitably include an undetected $��_��$. As a consequence, the angular distribution of this decay cannot be measured. In this work, we construct a {\it measurable} angular distribution by considering the subsequent decay $��^- \to ��^- ��_��$. The full cascade decay is $B_c^- \to J/��(\to ��^+ ��^-)��^- (\to ��^- ��_��)\bar��_��$, in which the three-momenta $\boldsymbol{p}_{��^+}$, $\boldsymbol{p}_{��^-}$, and $\boldsymbol{p}_{��^-}$ can be measured. The five-fold differential angular distribution containing all Lorentz structures of the new physics (NP) effective operators can be written in terms of twelve angular observables $\mathcal{I}_i (q^2, E_��)$. Integrating over the energy of pion $E_��$, we construct twelve normalized angular observables $\widehat{\mathcal{I}}_i(q^2)$ and two lepton-flavor-universality ratios $R(P_{L,T}^{J/��})(q^2)$. Based on the $B_c \to J/��$ form factors calculated by the latest lattice QCD and sum rule, we predict the $q^2$ distribution of all $\widehat{\mathcal{I}}_i$ and $R(P_{L,T}^{J/��})$ both within the Standard Model and in eight NP benchmark points. We find that the benchmark BP2 (corresponding to the hypothesis of tensor operator) has the greatest effect on all $\widehat{\mathcal{I}}_{i}$ and $R(P_{L,T}^{J/��})$, except $\widehat{\mathcal{I}}_{5}$. The ratios $R(P_{L,T}^{J/��})$ are more sensitive to the NP with pseudo-scalar operators than the $\widehat{\mathcal{I}}_{i}$. Finally, we discuss the symmetries in the angular observables and present a model-independent method to determine the existence of tensor operators., 29 pages, 3 figures, matches to the version published in JHEP