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Solar-thermal storage with phase-change material (PCM) plays an important role in solar energy utilization. However, most PCMs own low thermal conductivity which restricts the thermal charging rate in bulk samples and leads to low solar-thermal conversion efficiency. Here, we propose to regulate the solar-thermal conversion interface in spatial dimension by transmitting the sunlight into the paraffin-graphene composite with side-glowing optical waveguide fiber. This inner-light-supply mode avoids the overheating surface of the PCM, accelerates the charging rate by 123% than that of the traditional surface irradiation mode and increases the solar thermal efficiency to ~94.85%. Additionally, the large-scale device with inner-light-supply mode works efficiently outdoors, indicating the potential of this heat localization strategy in practical application. Phase change material for solar-thermal energy storage is widely studied to counter the mismatch between supply and demand in solar energy utilization. Here, authors introduce optical waveguide to regulate the solar-thermal conversion interface to enable the fast energy harvesting in solar-thermal energy storage system.

Peptide modification methods that do not rely on the cysteine residue are underdeveloped, and their development could greatly expand the current toolbox for peptide chemistry. During the course of preliminary investigations into the classical ortho -phthalaldehyde (OPA)-amine-thiol condensation reaction, we found that in the absence of thiol, OPA readily condenses with two primary alkyl amines to form a class of underexplored isoindolin-1-imine compounds under mild aqueous conditions. From the intramolecular version of this OPA-2amines reaction, an efficient and selective methodology using mild reaction conditions has been developed for stapling unprotected peptides via crosslinking of two amino groups in both an end-to-side and side-to-side fashion. The stapling method is superfast and broadly applicable for various peptide substrates with the reacting amino groups separated by a wide range of different amino acid units. The macrocyclization reactions of selected substrates are completed within 10 seconds at 5 mM concentration and within 2 minutes at 50 μM concentration. Importantly, the resulting cyclized peptides with an isoindolinimine linkage can be extended in a one-pot sequential addition manner with several different electron-deficient π electrophiles, thereby generating more complex structures. Methods for peptide stapling, or covalently linking amino acid residues to create a non-linear structure, mostly rely on cysteine residues, which imposes a significant practical limitation. Here the authors disclose a method to chemoselectively macrocyclize two free-amine-containing residues in mild, peptide-relevant conditions, using a commercially available reagent.

Predicting the corrosion rate for soil-buried steel is significant for assessing the service-life performance of structures in soil environments. However, due to the large amount of variables involved, existing corrosion prediction models have limited accuracy for complex soil environment. The present study employs three machine learning (ML) algorithms, i.e., random forest, support vector regression, and multilayer perception, to predict the corrosion current density of soil-buried steel. Steel specimens were embedded in soil samples collected from different regions of the Wisconsin state. Variables including exposure time, moisture content, pH, electrical resistivity, chloride, sulfate content, and mean total organic carbon were measured through laboratory tests and were used as input variables for the model. The current density of steel was measured through polarization technique, and was employed as the output of the model. Of the various ML algorithms, the random forest (RF) model demonstrates the highest predictability (with an RMSE value of 0.01095 A/m 2 and an R 2 value of 0.987). In light of the feature selection method, the electrical resistivity is identified as the most significant feature. The combination of three features (resistivity, exposure time, and mean total organic carbon) is the optimal scenario for predicting the corrosion current density of soil-buried steel.

Lead-free halide perovskite materials possess low toxicity, broadband luminescence and robust stability compared with conventional lead-based perovskites, thus holding great promise for eyes-friendly white light LEDs. However, the traditionally used preparation methods with a long period and limited product yield have curtailed the commercialization of these materials. Here we introduce a universal hydrochloric acid-assistant powder-to-powder strategy which can accomplish the goals of thermal-, pressure-free, eco-friendliness, short time, low cost and high product yield, simultaneously. The obtained Cs 2 Na 0.9 Ag 0.1 In 0.95 Bi 0.05 Cl 6 microcrystals exhibit bright self-trapped excitons emission with quantum yield of (98.3 ± 3.8)%, which could retain (90.5 ± 1.3)% and (96.8 ± 0.8)% after continuous heating or ultraviolet-irradiation for 1000 h, respectively. The phosphor converted-LED exhibited near-unity conversion efficiency from ultraviolet chip to self-trapped excitons emission at ~200 mA. Various ions doping (such as Cs 2 Na 0.9 Ag 0.1 InCl 6 :Ln 3+ ) and other derived lead-free perovskite materials (such as Cs 2 ZrCl 6 and Cs 4 MnBi 2 Cl 12 ) with high luminous performance are all realized by our proposed strategy, which has shown excellent availability towards commercialization. A general hydrochloric acid-assistant powder-to-powder strategy was proposed for preparing a series of lead-free perovskite microcrystals, meeting the needs of rapid preparation, mass production and remarkable fluorescent performance, simultaneously.

This study aimed to assess dynamic changes in emotional and behavioral problems among children with Attention-Deficit/Hyperactivity Disorder (ADHD) in Shanghai, China. Using a longitudinal design, school-aged children with ADHD were enrolled and followed, with emotional and behavioral measures repeatedly assessed. Due to varying COVID-19 measures and changing epidemics, and no intervention was admitted, an event-based longitudinal design was adopted, using calendar time from the enrollment of the first participant. Data collection spanned various pandemic control stages, including the Shanghai lockdown (March 28–May 31, 2022). Emotional and behavioral trends were analyzed using a Generalized Additive Model to capture the nonlinear dynamics effectively. Overall, 1102 children with ADHD (mean: 9.2 ± 2.4 years, 83% boys) were enrolled. Emotional and behavioral issues fluctuated over time. Behavioral problems, including inattention, hyperactivity, and conduct issues, peaked around day 260 of isolation and then declined but resurged after the Shanghai lockdown. Emotional issues, such as anxiety and depression, showed a dual-peak pattern, with early pandemic rises and a second peak around day 400. Symptoms rebounded after lockdown and persisted for an extended period. Sub-analyses revealed that boys had higher scores in hyperactivity and oppositional defiance than girls, with no significant gender differences in emotional problems. ADHD-PI children had higher emotional problem scores, while ADHD-HI children exhibited more severe behavioral issues. This study highlights the substantial impact of prolonged COVID-19 measures on emotional and behavioral problems in ADHD children, particularly increased adaptive pressures post-lockdown. Phase-specific, individualized interventions are crucial to mitigate these challenges.

Peripheral nerve injury is a serious medical problem with limited surgical and clinical treatment options. It is of great significance to integrate multiple guidance cues in one platform of nerve guidance conduits (NGCs) to promote axonal elongation and functional recovery. Here, a multi‐functional NGC is constructed to promote nerve regeneration by combining ordered topological structure, density gradient of biomacromolecular nanoparticles, and controlled delivery of biological effectors to provide the topographical, haptotactic, and biological cues, respectively. On the surface of aligned polycaprolactone nanofibers, a density gradient of bioactive nanoparticles capable of delivering recombinant human acidic fibroblast growth factor is deposited. On the graded scaffold, the proliferation of Schwann cells is promoted, and the directional extension of neurites from both PC12 cells and dorsal root ganglions is improved in the direction of increasing particle density. After being implanted in vivo for 6 and 12 weeks to repair a 10‐mm rat sciatic nerve defect, the NGC promotes axonal elongation and remyelination, achieving the regeneration of the nerve not only in anatomical structure but also in functional recovery. Taken together, the NGC provides a favorable microenvironment for peripheral nerve regeneration and holds great promise for realizing nerve repair with an efficacy close to autograft. A multi‐functional electrospun fiber‐based NGC is constructed to promote nerve regeneration by combining ordered topological structure, density gradient of biomacromolecular nanoparticles, and controlled delivery of biological effectors to provide the topographical, haptotactic, and biological cues, respectively.

Lithium–sulfur (Li–S) battery is attracting increasing interest for its potential in low‐cost high‐density energy storage. However, it has been a persistent challenge to simultaneously realize high energy density and long cycle life. Herein, we report a synergistic strategy to exploit a unique nitrogen‐doped three‐dimensional graphene aerogel as both the lithium anode host to ensure homogeneous lithium plating/stripping and mitigate lithium dendrite formation and the sulfur cathode host to facilitate efficient sulfur redox chemistry and combat undesirable polysulfide shuttling effect, realizing Li–S battery simultaneously with ultrahigh energy density and long cycle life. The as‐demonstrated polysulfide‐based device delivers a high areal capacity of 7.5 mAh/cm2 (corresponds to 787 Wh/L) and an ultralow capacity fading of 0.025% per cycle over 1000 cycles at a high current density of 8.6 mA/cm2. Our findings suggest a novel strategy to scale up the superior electrochemical property of every microscopic unit to a macroscopic‐level performance that enables simultaneously high areal energy density and long cycling stability that are critical for practical Li–S batteries. An overarching strategy was proposed to synergistically densify the sulfur cathode and stabilize the lithium anode by using a three‐dimensional graphene architecture. Benefiting from the unique structural properties to suppress the lithium dendrite growth and overcome the major limitations associated with dense and thick sulfur cathode, a high energy density yet long cycle life Li–S battery is fabricated.

The functionalization of noble metals is an effective approach to lowering the sensing temperature and improving the sensitivity of metal oxide semiconductor (MOS)-based gas sensors. However, there is a dearth of comparative analyses regarding the differences in sensitization mechanisms between the two functionalization modes of noble metal loading and doping. In this investigation, we synthesized Pt-doped CuO gas-sensing materials using a one-pot hydrothermal method. And for Pt-loaded CuO, Pt was deposited on the synthesized pristine CuO surface by using a dipping method. We found that both functionalization methods can considerably enhance the response and selectivity of CuO toward NO2 at low temperatures. However, we observed that CuO with Pt loading had superior sensing performance at 25 °C, while CuO with Pt doping showed more substantial response changes with an increase in the operating temperature. This is mainly due to the different dominant roles of electron sensitization and chemical sensitization resulting from the different forms of Pt present in different functionalization modes. For Pt doping, electron sensitization is stronger, and for Pt loading, chemical sensitization is stronger. The results of this study present innovative ideas for understanding the optimization of noble metal functionalization for the gas-sensing performance of metal oxide semiconductors.

The impact of cadmium (Cd) and fluorine (F) on plant and human health has provoked significant public concern; however, their combined effects on plant and soil bacterial communities have yet to be determined. Here, a pot experiment was conducted to evaluate the effects of exogenous F, Cd, and their combination (FCd) on lettuce growth and soil bacterial communities. The results revealed that F and Cd concentrations in lettuce ranged from 63.69 to 219.45 mg kg−1 and 1.85 to 33.08 mg kg−1, respectively, presenting lower values in shoots than in the roots. Moreover, low contamination levels had no discernable influence on lettuce growth, but showed a synergistic negative on plant biomass when exogenous F and Cd exceeds 300 and 1.0 mg kg−1, respectively. The results of 16S rRNA gene sequencing indicated that the most abundant bacterial community at the phylum level was Proteobacteria, with the relative abundance ranging from 33.42% to 44.10% across all the treatments. The contaminants had little effect on bacterial richness but impacted the structure of bacterial communities. The PCoA showed that compartment and contaminants were the primary contributors to the largest source of community variation, while the VPA indicated that F and Cd synergistically affected the bacterial communities. In turn, lettuce plants could enhance the resistance to the combined stress by increasing the relative abundance of Oxyphotobacteria, Subgroup 6, Thermoleophilia, and TK10 classes in the rhizosphere.

Populus sect. Turanga (hereafter referred to as “ Populus ”), including Populus euphratica and Populus pruinosa , are the predominant tree species in desert riparian forests in northwestern China. These trees play key roles in maintaining ecosystem balance, curbing desertification, and protecting biodiversity. However, the distribution area of Populus forests has been severely diminished and degraded in recent years due to increased habitat destruction and human activity. Understanding the genetic diversity among Populus individuals and populations is essential for designing conservation strategies, but comprehensive studies of their genetic diversity in northwest China are lacking. Here, we assessed the population structures and genetic diversity of 1,620 samples from 85 natural populations of Populus (59 P. euphratica and 26 P. pruinosa populations) covering all of northwestern China using 120 single nucleotide polymorphism (SNP) markers. Analysis of population structure revealed significant differentiation between these two sister species and indicated that strong geographical distribution patterns, a geographical barrier, and environmental heterogeneity shaped the extant genetic patterns of Populus . Both P. euphratica and P. pruinosa populations in southern Xinjiang had higher genetic diversity than populations in other clades, perhaps contributing to local geographic structure and strong gene flow. Analysis of molecular variance (AMOVA) identified 15% variance among and 85% variance within subpopulations. Mantel tests suggested that the genetic variation among P. euphratica and P. pruinosa populations could be explained by both geographical and environmental distance. The genetic diversity of P. euphratica showed a significant negative correlation with latitude and longitude and a positive correlation with various environmental factors, such as precipitation of warmest quarter and driest month, temperature seasonality, and annual mean temperature. These findings provide insights into how the genetic differentiation of endangered Populus species was driven by geographical and environmental factors, which should be helpful for designing strategies to protect these genetic resources in the future.