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This study focuses on the structural rearrangements and the photoluminescent behavior of pyrolytically derived carbon dots when subjected to a series of cyclic voltammetry sweeps. Although the electrical signals involved are not pronounced, multiple electrochemical cycling results in a progressive suppression of the photoluminescence, so that after 42 sweeps the intensity is reduced by one order of magnitude. At the same time, the fluorescence component stemming from the organic fluorophores is blue-shifted, while the contribution of the carbogenic cores is red-shifted. XPS and FTIR spectra reveal that the voltammetric field induces an extensive formation of C–O and C=O at the expense of the C=C bonds. Our findings indicate a close relationship between the electrochemical response and the structure of C-dots and, thus, have direct implications on the development of C-dot based electroluminescent materials, electrochemical sensors and solar cells. [ABSTRACT FROM AUTHOR]

Iodide–fullerene π interactions play decisive roles in n-doping and electron transport of fullerenes at the perovskite–PCBM interface in the devices of perovskite solar cells (Pero-SCs). But instability issues of perovskites due to halide anion migration greatly limit the practical application of Pero-SCs. To fully understand the properties of these interactions, we conducted systematic studies on fullerene ammonium halides containing I−, Br−, and Cl− that exist in perovskites. Our findings show that fullerene is an overwhelmingly strong electron acceptor that activates relatively inert halide anions (Br− and Cl−) and initiates the n-doping process by forming anion–π interactions, which are closely related to the performance and stability of the p–i–n Pero-SC devices based on a CH3NH3PbX3 (X = I, Br, and Cl) light absorber and a fullerene (C60 or PCBM) electron transport layer (ETL). At the perovskite–fullerene interface in the p–i–n Pero-SC, n-doping occurs by forming iodide–fullerene π interactions, which facilitates charge transport and improves the performance of the devices by suppressing hysteresis. On the basis of experimental evidence and computational results, we propose a plausible mechanism for iodide migration attributed to its n-doping at the interface and subsequent hopping of slidable iodide to a neighbouring fullerene given that space and energy are favorable. Thus, the migration of halide anions through the fullerene layer results in perovskite degradation and performance decay of the devices. This work highlights the importance of halide anion–fullerene π interactions in materials chemistry and explores the introduction of a halide anion blocking ETL in p–i–n Pero-SCs. [ABSTRACT FROM AUTHOR]

Multi-yolk–shell Bi@C nanostructures were prepared via a facile one-pot template-free hydrothermal approach. The prepared Bi@C nanostructures can act as a solid catalyst in the thermal decomposition of cyclotrimethylenetrinitramine (RDX) and display excellent catalytic activity, which highlights their application in the field of energetic materials. [ABSTRACT FROM AUTHOR]

Interface engineering is an important and efficient way to further improve the conversion efficiency of perovskite solar cells. In this study, we report the modification of the electron transport layer (ETL) using a thin layer of PEO. Characterizations showed that PEO was uniformly coated on top of the original TiOx ETL, without resulting in an evident change of the surface morphology, hydrophilic ability or transparency. With the interface dipole formed at the interface, the work function of the ETL greatly decreased. Compared with devices with TiOx only, devices based on the modified ETL gave a nearly 15% enhancement to the overall conversion efficiency, with both Voc and Jsc improved. Further studies showed that the improved performance could mainly be attributed to the better retardation of back recombination and the enhanced electron collection efficiency by means of the PEO thin layer modification. [ABSTRACT FROM AUTHOR]

A series of calcium-exchanged zeolite A samples with different degrees of exchange were prepared. They were characterized by powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC). High temperature oxide melt drop solution calorimetry measured the formation enthalpies of hydrated zeolites CaNa-A from constituent oxides. The water content is a linear function of the degree of exchange, ranging from 20.54% for Na-A to 23.77% for 97.9% CaNa-A. The enthalpies of formation (from oxides) at 25 °C are −74.50 ± 1.21 kJ mol−1 TO2 for hydrated zeolite Na-A and −30.79 ± 1.64 kJ mol−1 TO2 for hydrated zeolite 97.9% CaNa-A. Dehydration enthalpies obtained from differential scanning calorimetry are 32.0 kJ mol−1 H2O for hydrated zeolite Na-A and 20.5 kJ mol−1 H2O for hydrated zeolite 97.9% CaNa-A. Enthalpies of formation of Ca-exchanged zeolites A are less exothermic than for zeolite Na-A. A linear relationship between the formation enthalpy and the extent of calcium substitution was observed. The energetic effect of Ca-exchange on zeolite A is discussed with an emphasis on the complex interactions between the zeolite framework, cations, and water. [ABSTRACT FROM AUTHOR]

The properties of zeolite A change significantly upon sodium–calcium exchange. The impact of cation composition on the temperature-induced phase transformations and energetics of Na–Ca exchanged zeolite A was studied systematically using powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and high-temperature oxide melt solution calorimetry. As the temperature increases, the structural evolution of each Na–Ca exchanged zeolite A sample undergoes three distinct stages – dehydration, amorphization, and densification/recrystallization. Initially complete dehydration does not result in framework degradation, but further heating leads to zeolite phase degradation into other aluminosilicate phases. Both amorphization and recrystallization shift to higher temperatures as the calcium content increases. On the other hand, the enthalpies of formation for the high temperature aluminosilicate phases, the amorphous phase (AP) and the dense phase (DP), appear to be a linear function of calcium content (average ionic potential) with diminishing of energetic stability upon increasing the Ca content. 100% Na-A heated at 1200 °C has the most exothermic enthalpy of formation from oxides (−65.87 ± 0.87 kJ mol−1– TO2), while 97.9% CaNa-A heated at 945 °C has the least exothermic value (−5.26 ± 0.62 kJ mol−1– TO2). For different aluminosilicates with the same chemical composition, the dense phase (DP) assemblage is more stable than the amorphous phase (AP). [ABSTRACT FROM AUTHOR]

Lithium–oxygen batteries have attracted considerable attention due to their expected specific energy being far higher than that of lithium-ion batteries. The high charge overpotentials of the cathodic oxygen evolution reaction of insulator lithium peroxide is one of the critical challenges for practical implementation of lithium–oxygen batteries, which results in low energy efficiency and poor stability of cathodes and electrolytes. Transition metal oxides are known to be the most active electrocatalysts that can dramatically decrease the charging overpotentials of rechargeable lithium–air batteries. However, the poor electrical conductivity of these oxide electrocatalysts, such as RuO2, MnO2 and Co3O4, limits the charge transport of cathodic reactions and the full utilization of their catalytic activities. Herein, we exploit the high oxygen evolution reaction activities of oxides by incorporating insulator oxides into the pore channels of highly conductive nanoporous gold to form three-dimensional nanoporous core–shell composites. The hybrid catalysts as the cathodes of rechargeable lithium–oxygen batteries show highly reversible cathodic reactions at extremely lower overpotentials for high efficiency lithium–air batteries, arising from the synergistic effect of high conductive nanoporous gold (NPG) and catalytically active metal oxides. [ABSTRACT FROM AUTHOR]

The thermodynamic stability of Th-doped yttrium iron garnet (Y3Fe5Oi2, YIG) as a possible actinide-bearing material has been investigated using calorimetric measurements and first-principles electronic-structure calculations. Yttrium iron garnet with thorium substitution ranging from 0.04 to 0.07 atoms per formula unit (Y3_xThxFe5O12, x = 0.04-0.07) was synthesized using a citrate-nitrate combustion method. High- temperature oxide melt solution calorimetry was used to determine their enthalpy of formation. The thermodynamic analysis demonstrates that, although the substitution enthalpy is slightly endothermic, an entropic driving force for the substitution of Th for Y leads to a near-zero change in the Gibbs free energy. First-principles calculations within the density functional theory (DFT) indicate that the main limiting factors for Th incorporation into the YIG structure are the narrow stability domain of the host YIG and the formation of ThO2 as a secondary phase. Nevertheless, the defect formation energy calculations suggest that by carefully tuning the atomic and electronic chemical potentials, Th can be incorporated into YIG. The thermodynamic results, as a whole, support the possible use of garnet phases as nuclear waste forms; however, this will require careful consideration of the repository conditions. [ABSTRACT FROM AUTHOR]

A comprehensive analysis of Bi x O y Br z has been carried out using first-principles density-functional theory (DFT) to explore the electronic structure, energy band structure, and essential properties related to its photocatalytic performance. DFT calculations reveal that BiOBr, Bi 4 O 5 Br 2 , Bi 12 O 16 Br 5 , Bi 24 O 31 Br 10 , Bi 3 O 4 Br, and Bi 5 O 7 Br have different indirect bandgap values of 2.46 eV, 2.51 eV, 1.67 eV, 2.21 eV, 2.21 eV, and 2.87 eV, respectively, and these differences reflect the influence of material composition and structure on its electronic structure. When analyzing their optical characteristics, we observe that the dielectric function's real and imaginary components show peaks in the low-energy regime, indicating a material that is more responsive to light in these energy ranges. The absorption spectra show that the Bi x O y Br z material absorbs the highest amount of UV light absorption, and as the ratio of Bi to Br changes, the absorption spectra exhibit a red shift, which enhances the material's visible light absorption and thus improves the utilization of light. These light absorption properties make Bi x O y Br z materials potentially advantageous for enhancing photoelectric conversion efficiency, which is particularly important for producing microelectronic and optoelectronic devices.

An atmospheric oxygen-mediated oxidative coupling of primary and secondary alcohols for the synthesis of nitrogen-containing heterocycles has been developed. This method utilizes atmospheric oxygen as the sole, environmentally friendly oxidant to convert a variety of alkyl and aromatic primary alcohols into aldehyde equivalents, avoiding over-oxidation to carboxylic acids. Notably, these mild oxidation conditions are compatible with both primary and secondary alkyl alcohols as substrates.

We demonstrate low energy, forming and compliance-free operation of a resistive memory obtained by the partial oxidation of a two-dimensional layered van-der-Waals semiconductor: hafnium disulfide (HfS 2 ). Semiconductor-oxide heterostructures are achieved by low temperature (<300 °C) thermal oxidation of HfS 2 under dry conditions, carefully controlling process parameters. The resulting HfO x S y /HfS 2 heterostructures are integrated between metal contacts, forming vertical crossbar devices. Forming-free, compliance-free resistive switching between non-volatile states is demonstrated by applying voltage pulses and measuring the current response in time. We show non-volatile memory operation with an R ON / R OFF of 102, programmable by 80 ns WRITE and ERASE operations. Multiple stable resistance states are achieved by modulating pulse width and amplitude, down to 60 ns, < 20 pJ operation. This demonstrates the capability of these devices for low-energy, fast-switching and multi-state programming. Resistance states were retained without fail at 150 °C over 10 4 s, showcasing the potential of these devices for long retention times and resilience to ageing. Low-energy resistive switching measurements were repeated under vacuum (8.6 mbar) showing unchanged characteristics and no dependence of the device on surrounding oxygen or water vapour. Using a technology computer-aided design (TCAD) tool, we explore the role of the semiconductor layer in tuning the device conductance and driving gradual resistive switching in 2D HfO x -based devices.

A polyvinylidene carbonate:BN layer was constructed between Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 (LATP) and the lithium (Li) electrode, improving interfacial compatibility and thermal stability. The Li 3 N-rich solid electrolyte interphase regulates Li deposition behaviors. The solid-state Li metal batteries (SSLMBs) show remarkable electrochemical performance, exhibiting endurance for 800 hours of cycling at 0.2 mA cm -2 and a critical current density of 1.4 mA cm -2 . These studies provide guidance for interface engineering in SSLMBs.

Inspired by biosynthetic peptides, we investigate the chiral recognition properties of adenylate amidate ( N -aa-AMP, a potential analog of 5'-aa-AMP) in prebiotic peptide formation. Our findings demonstrate that N -L-aa-AMP preferentially binds to L-aa, facilitating the formation of homochiral peptides, while N -D-aa-AMP shows a preference for D-aa, thereby achieving homochirality in peptide synthesis. Collectively, these results enhance our understanding of the evolutionary origins of homochirality on prebiotic Earth.

About 60 nm Sb 2 Se 3 nanoparticles are uniformly embedded in a porous carbon substrate to prepare a Sb 2 Se 3 /C composite through a combination of pyrolysis reduction and solid-phase selenization. The Sb 2 Se 3 /C anode exhibits excellent sodium storage capacity. The initial discharge capacity is up to 420 mA h g -1 at 0.1 A g -1 , and the specific capacity still remains 339 mA h g -1 after 1000 cycles, with a high capacity retention rate of 80%.

Flexible hydrogel sensors have found extensive applications. However, the insufficient sensing sensitivity and the propensity to freeze at low temperatures restrict their use, particularly in frigid conditions. Herein, a multifunctional eutectogel with high transparency, anti-freezing, anti-swelling, adhesive, and self-healing properties is prepared by a one-step photopolymerization of acrylic acid and lauryl methacrylate in a binary solvent comprising water and deep eutectic solvent (DES). The results from the molecular dynamics simulations and density functional theory indicate that the hydrogen bonds between DES and water mixtures possess better stability than those between water molecules. On the other hand, DES breaks down hydrogen bonds in water, providing eutectogels with excellent anti-freezing even at -60 °C. Cetyltrimethylammonium bromide is incorporated to establish stable hydrophobic interactions and electrostatic attractions with polymer chains in the eutectogel network, resulting in superior mechanical (elongation at break of 2890%) and anti-swelling (only 2% swelling in water over 7 days) properties. The eutectogel-based strain sensors exhibit remarkable sensitivity, achieving a gauge factor of up to 15.4. The multifunctional eutectogel sensors can monitor motion and transmit encrypted information at low temperatures, demonstrating considerable potential for applications in flexible electronics within low-temperature environments.

Commercial lithium-ion batteries that use flammable liquid electrolytes face significant safety risks, such as fires caused by electrolyte leaks. Solid polymer electrolytes (SPEs) present a viable solution to this problem, with ether-based polymer electrolytes standing out due to their superior stability and compatibility with lithium metal. The in situ ring-opening polymerization of cyclic ether monomers not only simplifies the battery manufacturing process but also improves the solid/solid interfacial contacts between electrolytes and electrodes, thereby significantly reducing interfacial impedance. In this paper, we review the mechanisms of ring-opening polymerization for cyclic ether monomers and analyze the ionic conduction of ether-based polymer electrolytes. We also explore the in situ curing mechanisms for several representative cyclic ether monomers and assess research advancements in this area. Additionally, this paper discusses the sustainability of ether-based polymer electrolytes and provides an outlook on future research and sustainability initiatives in the field.

Microfluidic chips exhibit unique advantages in both economy and rapidity, particularly for the separation and detection of biomolecules. In this review, we first introduced the mechanisms of several electrically driven methods, such as electrophoresis, dielectrophoresis, electro-wetting and electro-rotation. We then discussed in detail the application of these methods in nucleic acid analysis, protein manipulation and cell treatment. In addition, we outlined the considerations for material selection, manufacturing processes and structural design of microfluidic chips based on electrically driven mechanisms., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

CO 2 conversion and reuse technology are crucial for alleviating environmental stress and promoting carbon cycling. Reverse water gas shift (RWGS) reaction can transform inert CO 2 into active CO. Molybdenum carbide (MoC) has shown good performance in the RWGS reaction, and different crystalline phases exhibit distinct catalytic behaviors. Here, we performed a systematic study on the RWGS reaction mechanism on the hexagonal-phase γ-MoC(100) surface by using density functional theory (DFT). It is found that the redox mechanism, i.e. the direct dissociation of CO 2 , is the dominant pathway. CO 2 firstly adsorbs on the surface with an adsorption energy of -2.14 eV, and then dissociates into CO* and O* with a barrier of 0.83 eV. Surface O* hydrogenating into OH* has a high barrier of 2.15 eV. OH* further hydrogenating into H 2 O* has a barrier of 1.48 eV, and the disproportionation of OH* considerably lowers this value to 0.06 eV. However, the desorption of product CO is particularly challenging due to the large energy demand of 3.06 eV. This characteristic, in turn, provides feasibility and opportunity for CO 2 to serve as a potential alternative carbon source for CO on the γ-MoC(100) surface. In contrast, other Mo-based catalysts such as hexagonal MoP and cubic α-MoC have better RWGS catalytic efficiency., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Background and aims. Undernutrition coexists with tuberculosis and is associated with adverse treatment outcomes. Nutrition packages have been incorporated into tuberculosis patient care in some regions but there are little data on its effectiveness. The aim of this study is to evaluate the effect of a nutrition package on the treatment response and nutritional status of tuberculosis patients. Methods. We conducted a double-blinded placebo-controlled randomized trial in 360 pulmonary tuberculosis patients with concurrent diabetes or prediabetes. The participants were randomly assigned to receive a daily nutrition package (112 kcal, 9 g protein, and micronutrients) or a daily placebo package (112 kcal, 3 g protein, and no micronutrients) during tuberculosis treatment. The intervention lasted for six months. All participants received standard pulmonary tuberculosis treatment. The clinical symptoms, sputum smear, chest computed tomography, and nutritional status were monitored during the intervention. Results. The nutrition package improved the expectoration (intervention vs. placebo: 34.1% vs. 48.3% in week 1, 27.8% vs. 45.0% in week 2, 25.9% vs. 38.6% in week 3, 25.6% vs. 35.4% in month 1, 15.3% vs. 22.9% in month 2) and chest pain (2.3% vs. 9.0% in week 3, 3.6% vs. 8.3% in month 1, 4.3% vs. 10.0% in month 2, 1.8% vs. 6.4% in month 4). The nutrition package also increased hemoglobin, albumin, and lymphocyte counts. The nutrition package did not influence the sputum smear conversion in the whole population [hazard ratio (95% CI): 1.031 (0.685, 1.550), P = 0.885], but accelerated the conversion in patients without cavity [2.583 (1.180, 5.656), P = 0.018]. Conclusions. The nutrition package improved the clinical symptoms ( e.g. chest pain and expectoration) and alleviated undernutrition ( e.g. anemia and hypoproteinemia) among tuberculosis patients. The study was registered at the China Clinical Trial Registry Center (no. ChiCTR1900022294; https://www.chictr.org.cn).

Electrochromic smart windows can realize intelligent photothermal regulation by applying a low potential, which is of great significance for energy-saving buildings and achieving low carbon emission. However, the dense structure of conventional metal oxide electrochromic materials limits ion transport efficiency, resulting in poor electrochromic properties. Here, we propose a surface crystal reconstruction strategy for cubic NiO through phosphorylation (P-NiO) to build energetic reactive interfaces and enhance the electrochromic performance. Theoretical simulations and experiments reveal that the introduction of PO 4 tetrahedra tailored the crystal structure of cubic NiO, which endows it with a large number of contiguous intracrystal cavities and unsaturated P-O bonds on the surface. The energetic reactive interface optimizes the transport path of OH - and gets rid of the dependence on K + in the adsorption process, thus improving the reaction kinetics of NiO. The P-NiO film delivers a large optical modulation (90.3%, at 500 nm), a high coloration efficiency (81.1 cm 2 C -1 , at 500 nm), and a fast switching speed (6 s and 7.2 s for coloring and bleaching processes). Furthermore, a model of an electrochromic smart window was fabricated based on the P-NiO film, using which a potential energy saving of 60.81 MJ m -2 and CO 2 emission reduction of 11.98 kg m -2 can be achieved in hot climate zones according to energy simulations. The in-depth insights gained into the fundamental mechanism of this surface crystal reconstruction strategy will facilitate the rational design of high-performance electrochromic and electrochemical materials.

Facilitating rapid charge transfer in electrode materials necessitates the optimization of their ionic transport properties. Currently, only a limited number of Li/Na-ion organic cathode materials have been identified, and those exhibiting intrinsic solid-phase ionic conductivity are even rarer. In this study, we present tetra-lithium and sodium salts with the generic formulae: A 4 -Ph-CH 3 P and A 4 -Ph-PhP, wherein A = Li, Na; Ph-CH 3 P = 2,5-dioxido-1,4-phenylene bis(methylphosphinate); Ph-PhP = 2,5-dioxido-1,4-phenylene bis(phenylphosphinate), as novel alkali-ion reservoir cathode materials. Notably, A 4 -Ph-PhP exhibits impressive Li-ion and Na-ion conductivities, measured at 2.6 × 10 -7 and 1.4 × 10 -7 S cm -1 , respectively, in a dry state at 30 °C. To the best of our knowledge, these represent the first example of small-molecule organic cathode materials with intrinsic Li + and Na + conductivity. Theoretical calculations provide further insight into the electrochemical activity of the Li/Na-phenolate groups, as well as the enhanced electron affinity resulting from -phenyl and -Na substitutions. Additionally, Na 4 -Ph-PhP displays two distinct charge-discharge plateaus at approximately 2.2 V and 2.7 V, and 2.0 V and 2.5 V vs. Na + /Na, respectively, and demonstrates stable cycling performance, with 100 cycles at a rate of 0.1C and an impressive 1000 cycles at 1C. This study not only expands the portfolio of phenolate-based organic salts for use in metal-ion batteries but also underscores the potential of phosphonate-based organic materials in advancing energy storage technologies., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

The development of safe and efficient hemostatic materials is medically important to prevent death due to trauma bleeding. Exploiting the synergistic effect between the D-periodic functional domain of collagen fibrils on platelet activation and cationic chitosan on erythrocyte aggregation is expected to develop performance-enhanced hemostatic materials. In this study, we prepared collagen fibrils and chitosan composite hemostatic materials by modulating the self-assembled bionic fibrillation of collagen with different degrees of deacetylation (DD, 50%, 70% and 85%) of chitosan. The findings indicated that chitosan promoted collagen self-assembly, with all the collagen fibrils demonstrating a typical D-periodical structure similar to that of the native collagen. Furthermore, the composite demonstrated enhanced structural integrity and procoagulant capacity along with good biocompatibility. Notably, the fibrillar composites with 70% DD of chitosan exhibited optimal mechanical properties, procoagulant activity, and adhesion of erythrocytes and platelets. Compared to pure collagen fibrils and the commercial hemostatic agent Celox™, the collagen/chitosan fibrillar composite treatment significantly accelerated hemostasis in the rat tail amputation model and liver injury model. This research offers new insights into the development of hemostatic materials and indicates that collagen-chitosan composites hold promising potential for clinical applications.

A benzofuran-[ b ]-fused BODIPY trimer has been efficiently synthesized, featuring a unique structural design that harmoniously integrates TBET (through bond energy transfer) and PET (photo-induced electron transfer) mechanisms. This trimer boasts exceptional optical properties, including a large pseudo-Stokes shift of 100 nm, an impressive fluorescence quantum yield ( Φ FL = 0.931), an outstandingly high extinction coefficient (182 100 M -1 cm -1 ), a remarkable FEF (fluorescence enhancement factors, 22.4-fold) values as well as exhibiting AIE (aggregation-induced emission) activity, and has been successfully utilized in two-photon fluorescence imaging of live-cell lipid droplets.

Herein, we report an atomically dispersed Fe-N-C catalyst with axial oxygen ligands (FeN 4 O/NC) synthesized for the first time by ultrafast Joule heating. The formation of oxygen species between FeN 4 and graphene offers high activity and stability for the ORR. The calculations indicate that FeN 4 O/NC offers an optimal adsorption-desorption of oxygen-containing intermediates, providing a promising approach to designing efficient single-atom electrocatalysts.

Upper gastrointestinal bleeding (UGIB) is bleeding in the upper part of the gastrointestinal tract with an acidic and dynamic environment that limits the application of conventional hemostatic materials. This study focuses on the development of N -[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride/phytic acid (HTCC/PA, HP) powders with fast hemostatic capability and strong acid resistance, for potential applications in managing UGIB. Upon contact with liquids within 5 seconds, HP powders rapidly transform into hydrogels, forming ionic networks through electrostatic interactions. The ionic crosslinking process facilitates the HP powders with high blood absorption (3.4 times of self-weight), sufficient tissue adhesion (5.2 and 6.1 kPa on porcine skin and stomach, respectively), and hemostasis (within 15 seconds for in vitro clotting). Interestingly, the PA imparts the HP powders with strong acid resistance (69.8% mass remaining after 10 days of incubation at pH 1) and on-demand removable sealing while HTCC contributes to fast hemostasis and good wet adhesion. Moreover, the HP powders show good biocompatibility and promote wound healing. Therefore, these characteristics highlight the promising clinical potential of HP powders for effectively managing UGIB.

Effective angiogenesis is essential for creating complex vascular networks in tissue engineering; however, there is a scarcity of safe and potent pro-angiogenic factors. Although a decellularized extracellular matrix (dECM) offers excellent biocompatibility and is widely used in tissue engineering as a pro-angiogenic additive, its conventional extraction technique resulting in significant loss of bioactivity limits clinical potential. The dorsal dermal tissue has rich blood perfusion and its dECM is rich in angiogenic factors. In this study, the dECM components from the dorsal dermis of mice (DD) were produced to enhance in vitro and in vivo pro-angiogenic abilities using a novel physical method. Morphological studies showed no significant difference between DD-wild-type (DD-wt) and DD-wild-type-newborn (DD-wtn), and there was also no difference in DNA or RNA concentration. In addition, DD-wtn outperformed DD-wt in maintaining the stemness of MSCs, promoting inflammatory response and facilitating endothelial cell differentiation. It is of greater significance to note that the dermal combined fibrous capsule thickness is greater in the DD-wt treated group than in the DD-wtn group. Furthermore, the number of blood vessels in the subcutaneously implanted scaffold with DD-wtn increased by 233%. Consequently, our current finding provides a promising strategy to produce a novel pro-angiogenic bioink additive for enhancing vascularization in 3D bioprinting.

Water microdroplets containing 100 μM HAuCl 4 have been shown to reduce gold ions into gold nanoparticles spontaneously. It has been suggested that this chemical transformation takes place exclusively at the air-water interface of microdroplets, albeit without mechanistic insights. We compared the fate of several metallic salts in water, methanol, ethanol, and acetonitrile in the bulk phase and microdroplet geometry (sprays). Experiments revealed that when HAuCl 4 (or PtCl 4 ) is added to bulk water (or methanol or ethanol), metal NPs appear spontaneously. Over time, the nanoparticles grow, evidenced by the bulk solutions' changing colors. If the bulk solution is sprayed pneumatically and microdroplets are collected, the NP size distribution is not significantly enhanced. We find that the reduction of metal ions is accompanied by the oxidation of water (or alcohols); however, these redox reactions are minimal in acetonitrile. This establishes that the spontaneous reduction of metal ions is (i) a bulk phase phenomenon in water and several non-aqueous solutions, (ii) minimally affected by the air-water interface or the microdroplet geometry, and (iii) is not limited to Au 3+ ions and can be explained via the electrochemical series. These results advance our understanding of aquatic chemistry and liquids in general and should be relevant in soil chemistry, biogeochemistry, electrochemistry, and green chemistry., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Modified magnetic chitosan nanoparticles (EMMCS-G), used as a Fenton-like catalyst, were successfully prepared and modified with glutaraldehyde and ethylenediamine. EMMCS-G has strong magnetization, good reusability, stability, environmental friendliness, and high efficiency. In the Fenton-like system, the synergistic effect of adsorption and advanced oxidation significantly enhances the removal effect of tetracycline (TC). The optimal concentration of persulfate was found to be 20 mmol L -1 , and at a pH of 3, the removal efficiency of TC reached 95.6% after 6 hours. The oxidation system demonstrated excellent pH adaptability, achieving a TC removal rate of 94% within 6 hours across a pH range of 3 to 8. Hydroxyl (˙OH) and sulfate (SO 4 - ˙ ) radicals were present in the reaction system, with ˙OH playing an important role in the oxidation process of TC. The attack sites of tetracycline were identified using density functional theory (DFT), and five degradation pathways for TC were proposed based on LS-MS experiments. Finally, quantitative structure-activity relationship (QSAR) analysis was employed to assess the toxicity of the intermediates. Overall, toxicity gradually decreased, indicating that the Fenton reaction system effectively reduced the toxicity and mutagenicity of TC. This study suggests EMMCS-G as a potential catalyst for enhanced Fenton-like degradation with excellent efficiency observed for the degradation of tetracycline for environmental remediation., Competing Interests: There is no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Covering: 2019 to 2023Isoquinoline alkaloids, an important class of N -based heterocyclic compounds, have attracted considerable attention from researchers worldwide. To follow up on our prior review (covering 2014-2018) and present the progress of this class of compounds, this review summarizes and provides updated literature on novel isoquinoline alkaloids isolated during the period of 2019-2023, together with their biological activity and underlying mechanisms of action. Moreover, with the rapid development of synthetic modification strategies, the synthesis strategies of isoquinoline alkaloids have been continuously optimized, and the total synthesis of these classes of natural products is reviewed critically herein. Over 250 molecules with a broad range of bioactivities, including antitumor, antibacterial, cardioprotective, anti-inflammatory, neuroprotective and other activities, are isolated and discussed. The total synthesis of more than nine classes of isoquinoline alkaloids is presented, and thirteen compounds constitute the first total synthesis. This survey provides new indications or possibilities for the discovery of new drugs from the original naturally occurring isoquinoline alkaloids.

Microorganisms constitute an essential component of the indoor ecosystem and may pose potential health risks after inhalation. However, evidence regarding the impact of indoor airborne microbiome on general respiratory health is scarce. Additionally, while air purification has been shown to be an effective strategy for controlling culturable bioaerosols, its impact on indoor airborne microbiome remains unclear. To determine the impact of indoor airborne microbial exposure on lung function, and whether and how air purification can modify indoor airborne microbiome, we conducted a randomized, double-blind, crossover study employing air purification intervention among 68 healthy young adults in Beijing, China. Indoor airborne bacteria and fungi were characterized using amplicon sequencing technology and quantified by qPCR. Our results indicated positive associations between indoor airborne microbial α-diversity and lung function indices; however, adverse effects from total microbial load were observed. Males were more susceptible to microbial exposure than females. Beneficial effects from richness in Actinobacteria, Bacteroidia, Oxyphotobacteria, Bacilli, Clostridia, Alphaproteobacteria, Gammaproteobacteria, Dothideomycetes, and Sordariomycetes, and detrimental effects from five Proteobacteria genera, including Dechloromonas , Hydrogenophaga , Klebsiella , Pseudomonas , and Tolumonas , were also identified. Air purification contributed to decreased fungal diversity and total fungal load, but not the overall microbial community structure. Our study demonstrates the significant role of indoor airborne microbiome in regulating human respiratory health and provides inspiration for improving health through manipulation of indoor microbiome. Meanwhile, our study also underscores the importance of balancing the potential benefits from decreased microbial load and the underlying risks from reduced microbial diversity while applying environmental microbial interventions.

Sb nanoparticles (∼50 nm) are embedded uniformly on the surface of carbon fibers (Sb NPs-SCFs) without scattered Sb NPs. The Sb NPs-CNFs anode exhibits excellent sodium storage, delivering a second cycle discharge capacity of 455.7 mA h g -1 at 1.0 A g -1 and a stable capacity of 381.9 mA h g -1 after 200 cycles, achieving a notable retention of 83.8%.

High-throughput and label-free protein nanopore-based sensors are extensively used in DNA sequencing, single-protein analysis, molecular sensing and chemical catalysis with single channel recording. These technologies show great potential for identifying various harmful substances linked to public health by addressing the limitations of current portability and the speed of existing techniques. In this review, we provide an overview of the fundamental principles of nanopore sensing, with a focus on chemical modification and genetic engineering strategies aimed at enhancing the detection sensitivity and identification accuracy of protein nanopores. The engineered protein nanopores enable direct sensing, while the introduction of aptamers and substrates enables indirect sensing, translating the physical structure and chemical properties of analytes into readable signals. These scientific discoveries and engineering efforts have provided new prospects for detecting and monitoring trace hazardous substances.

Nucleoside-derived supramolecular hydrogels based on G 4 -structures have been extensively developed in the biomedical sector and recognized for superior excellent biocompatibility and biodegradability. However, limited longevity and stability present a significant challenge. Chemical modifications in the molecular structure have been shown to enhance the longevity stability of G 4 -structure-based supramolecular hydrogels, but the precise way in which the molecular structure impacts the stability of the G 4 -structures and consequently affects the properties of the hydrogel remains to be elucidated. This issue represents a notable challenge in the field, which restricts their further applications to some extent. In this study, single crystals of Gd, αGd and αGd* were cultivated and compared with G. Notably, before this study, the single crystal structures of all natural nucleosides, with the exception of Gd, had been determined. The investigation into the molecular structure and supramolecular self-assembly properties of four guanosine analogs at the atomic scale revealed that the formation of G-quartets is critical for their ability to form hydrogels. The stability of the sugar ring geometry conformation (an intrinsic factor) and the disorder and strength of the hydration effect (extrinsic factors) are vital for maintaining the stability of the G 4 -structures. The rapid cooling changes the molecular geometry conformation, and the organic solvent changes the hydration effect, which can improve the longevity stability of G 4 -structure-based supramolecular hydrogels instead of chemical modifications. Consequently, the lifespan of the hydrogels was extended from 2 h to over one week. This advancement is expected to offer significant insights for future research in designing and developing G 4 -structure-based supramolecular hydrogels.

Ultraviolet (UV) birefringent crystals play a crucial role in various fields, such as laser technologies, optical telecommunications, and advanced scientific instrumentation. Alkali metal borates, with their diverse structures and remarkable ultraviolet optical properties, have garnered significant attention in recent years. In this study, employing the evolutionary crystal structure prediction algorithm USPEX, in conjunction with ionic substitutions and first-principles calculations, we systematically explored the pseudo-binary K 2 O-B 2 O 3 system and predicted two stable structures ( oP 56-K 3 BO 3 and mC 44-K 4 B 2 O 5 ) previously unreported, and twelve metastable structures in the K 2 O-B 2 O 3 system. A comprehensive analysis of their structural, electronic and optical properties is conducted. The coplanar arrangement of BO 3 and B 3 O 6 groups is found to enhance optical anisotropy, thereby increasing the birefringence. In the K 2 O-B 2 O 3 system, six structures with wide band gaps and high birefringence ( mP 28-1-K 3 BO 3 , tR 72-KBO 2 , oP 112-1-KB 5 O 8 , oP 112-2-KB 5 O 8 , mC 220-K 5 B 19 O 31 , and hR 21-K 3 BO 3 ) are found to be possible candidates for UV optical materials. Importantly, hR 21-K 3 BO 3 , the only non-centrosymmetric structure in this system, exhibits a significant frequency doubling coefficient (about 4.6 KDP) and a moderate birefringence index (0.056@1064 nm), marking it a promising UV nonlinear optical material.

We report a systematic molecular design in BF2bdk-based afterglow emitters with photoluminescence quantum yields up to 46.3% and lifetimes around 1 s. Suitable excited-state types, diverse excited state species, relatively small singlet-triplet energy gaps and strong dipole-dipole interactions are critical in determining the afterglow properties.

Herein, covalent organic polyrotaxanes (COPRs) were integrated with supermolecule self-assembly and dynamic imine bond formation to act as absorbents that captured radioactive iodine from water. The aromatic building blocks were initially complexed with β-cyclodextrin (β-CD) to form pseudorotaxanes, which were then condensed with aromatic tri-aldehyde via mechanical grinding and solvothermal synthesis in sequence. The threading of β-CD throughout the polymer skeleton effectively reduced the usage of expensive building blocks and significantly lowered the cost, while also remarkably enhancing the skeleton polarity, which is closely related to many special applications. Impressively, the threading of CD improved the water dispersibility of COPRs, which displayed an abnormally high iodine adsorption capacity. This novel synthetic strategy allows the incorporation of mechanically interlocked CDs into porous polymeric materials, which provides access to low-cost preparations of COPRs with a brand new structure for specific applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report the efficient synthesis of monomeric circular RNAs (circRNAs) in the size range of 16-44 nt with a novel DNA dumbbell splinting plus T4 DNA ligation strategy. Such a DNA dumbbell splinting strategy was developed by one group among ours recently for near-quantitative conversion of short linear DNAs into monomeric circular ones. Furthermore, using the 44 nt circRNA as scaffold strands, we constructed hybrid RNA:DNA and pure RNA:RNA double crossover tiles and their assemblies of nucleic acid nanotubes and flat arrays.