Influence of climate and land use on watershed anthropogenic phosphorus inputs and riverine phosphorus export dynamics: A global analysis.

Many studies have found predictive relationships between riverine phosphorus (P) export and net anthropogenic P inputs (NAPI) at the watershed scale, but the global or regional extent of these relationships has not been empirically quantified. Herein, we present a data-driven global assessment of the response of riverine total P (TP) fluxes to NAPI based on 358 watersheds. NAPI exhibited high spatial heterogeneity (2-12,085 kg P km-2 yr-1) and was well correlated with riverine TP fluxes. Riverine TP export fractions of NAPI were primarily regulated by NAPI components, hydroclimate factors, and land-use as determined through a random-forest meta-analysis. In watersheds dominated by disturbed land-use (e.g., agricultural and developed lands), runoff emerged as pivotal climate-related factors influencing riverine export fractions of NAPI. In watersheds dominated by natural land-use, runoff, precipitation and temperature were identified as the most critical factors. We developed a mixed-effects meta-regression model (R2 = 0.63-0.70, RMSE = 19-78 %, n = 87-202) to examine the quantitative relationship between riverine TP fluxes and NAPI, which avoids subjectivity in selecting influencing factors and regression forms. The model estimated that legacy P contributed 14-17 % of annual riverine TP fluxes in Chinese watersheds, 25 % in North American watersheds and 11-27 % in European watersheds. Annual NAPI contributions to annual riverine TP flux were 83-86 % in China, 75 % in North America and 73-89 % in Europe. The model forecasted 52-67 %, 69-71 % and 74-77 % reductions in riverine TP fluxes across Chinese, North American, and European watersheds by 2050 under five shared socio-economic pathway scenarios compared to 2010 baseline conditions, respectively. This study provides a straightforward and reliable method for quantifying anthropogenic P input and riverine P export dynamics within an acceptable error range. It provides guidance for developing phosphorus pollution control strategies to counter potential increases in phosphorus inputs due to expected changes in climate and land use.

Theranostic Bottle-Brush Polymers Tailored for Universal Solid-Tumor Targeting.

Designing an efficient nanocarrier to target multiple types of cancer remains a major challenge in the development of cancer nanomedicines. The majority of systemically administered nanoparticles (NPs) are rapidly cleared by the liver, resulting in poor tumor-targeting efficiency and severe side effects. Here, we present a delicately tailored design and synthesis of fluorescent bottle-brush polymers and screen nine derived NPs, each varying in size and surface coatings, for tumor imaging and targeted delivery. Our optimized polymer bearing (oligo(ethylene glycol) methyl ether methacrylate) in the side chains shows reduced macrophage uptake, prolonged blood-circulation time (up to 27 h), and exceptionally high accumulation in the tumor compared to the liver, elucidating an immune-evasion-induced tumor-targeting mechanism. High tumor accumulation significantly improved the antitumor efficacy. The outstanding tumor-targeting ability has been further validated across five distinct tumor models, including orthotopic glioblastoma and pancreatic cancer, which demonstrate the universality of our polymeric nanocarrier for tumor-targeting delivery.

Molecular and Supramolecular Materials: From Light-Harvesting to Quantum Information Science and Technology.

The past two decades have witnessed immense advances in quantum information technology (QIT), benefited by advances in physics, chemistry, biology, and materials science and engineering. It is intriguing to consider whether these diverse molecular and supramolecular structures and materials, partially inspired by quantum effects as observed in sophisticated biological systems such as light-harvesting complexes in photosynthesis and the magnetic compass of migratory birds, might play a role in future QIT. If so, how? Herein, we review materials and specify the relationship between structures and quantum properties, and we identify the challenges and limitations that have restricted the intersection of QIT and chemical materials. Examples are broken down into two categories: materials for quantum sensing where nonclassical function is observed on the molecular scale and systems where nonclassical phenomena are present due to intermolecular interactions. We discuss challenges for materials chemistry and make comparisons to related systems found in nature. We conclude that if chemical materials become relevant for QIT, they will enable quite new kinds of properties and functions.

Mussel-inspired polydopamine-modified biochar microsphere for reinforcing polylactic acid composite films: Emphasizing the achievement of excellent thermal and mechanical properties.

Having poor interfacial compatibility between biochar microsphere (BM) and polylactic acid (PLA) should be responsible for the unbalance of composite film strength and toughness. Elucidating the effect of polydopamine (PDA) on BM and BM/PLA composite films is the ultimate goal of this study based on the mussel bionic principle. It was found that the strong adhesion of PDA on the BM surface was achieved, which improved the surface roughness and thermal stability. Also, PDA modification can facilitate crystallization, increase thermal properties, improve interfacial compatibility, and enhance the tensile properties of BM/PLA composite films. Silane-based PDA modified BM/PLA composite film exhibited the best tensile strength, tensile modulus, and elongation at break with 77.95 MPa, 1.87 GPa, and 7.30%. These noteworthy findings, achieving a simultaneous improvement in PLA strength and toughness, hold promising implications for its sustainability.

Kinetic and Thermodynamic Control of Supramolecular Aggregation of Near Infrared Pyrrolopyrrole Cyanine Fluorophores Confined in Colloidal Nanoparticles.

Control of the intermolecular aggregation of organic π-conjugated molecules as chromophores is crucial for tuning their physical properties such as light absorption/emission, and energy and charge transfer. Lots of advances have been achieved in control of intermolecular aggregation of organic chromophores in solid states where an indefinitely large number of molecules are involved. However, much less understanding has been gained at a mesoscale of aggregates formed by well-defined organization of a deterministic number of chromophores, which has been realized in natural photosynthetic systems but still remains rare in manmade materials. Here, we report both the kinetic and the thermodynamic control of the supramolecular aggregation of a near-infrared cyanine dye, PPcy, and its derivatives confined in colloidal nanoparticles stabilized by surfactants in aqueous media. Our results demonstrate that both the aggregation number, the aggregation state and the optical properties of the PPcy chromophores are controllable through optimization of the alkyl and polymer chains tethered from PPcy, the effective concentration of the chromophore inside each particle, and the surfactants utilized to stabilize the colloids in water.

Anthraquinodimethane-Based Molecular Switches Tethered by Four-Arm Star-like Polymers.

Molecular switches that reversibly change their structures and physical properties are important for applications such as sensing and information processing at molecular scales. In order to avoid the intermolecular aggregation that is often detrimental to the stimuli-responses of molecular switches, previous studies of molecular switches have been often conducted in dilute solutions which are difficult for applications in solid-state devices. Here we report molecular design and synthesis that integrates anthraquinodimethane as molecular switching units into polymers with amenable processibility in solid states. Optical and electron spin resonance characterizations indicate that the four-arm polymers of poly(ϵ-caprolactone) or poly(D,L-lactide) tethered from anthraquinodimethane slow down the dynamics of the conformational switching between the folded and the twisted conformations, enhance the photoluminescence in solid states and impart materials with a small energy gap from singlet ground state to thermally accessible triplet state.

Evaluation of three prevalent global riverine nutrient transport models.

Global riverine nitrogen (N) and phosphorus (P) transport models offer important insights into basin nutrient cycling. However, appropriate model selection for a given research objective remains ambiguous. This study conducted a meta-analysis to evaluate the performance and applicability of three prevalent global riverine nutrient transport models: Global NEWS, IMAGE-GNM, and WorldQual. According to performance criteria (satisfactory: R2 > 0.50 and NSE > 0.50), the Global NEWS model performs satisfactorily in simulating dissolved organic nitrogen (DON; n = 101, R2 = 0.58, NSE = 0.57) and dissolved organic phosphorus loads (DOP; n = 80, R2 = 0.59, NSE = 0.59). The model falls short in simulating dissolved inorganic nitrogen (DIN; n = 644, R2 = 0.56, NSE = - 0.80) and dissolved inorganic phosphorus loads (DIP; n = 450, R2 = 0.33, NSE = - 0.12). The IMAGE-GNM model shows satisfactory accuracies in simulating riverine total nitrogen (TN; n = 831, R2 = 0.56, NSE = 0.53) and total phosphorus (TP; n = 902, R2 = 0.59, NSE = 0.48) concentrations, particularly in European basins. The WorldQual model presented unsatisfactory performance in simulating riverine TN (n = 11, R2 = 0.76, NSE = 0.34) and TP (n = 13, R2 = 0.71, NSE = - 0.25) concentrations. Using a two-segment linear model, we recommend the Global NEWS model for basins larger than 2.2 × 104 km2 for DIN and 3.2 × 104 km2 for DIP. The IMAGE-GNM model is best suited for basins with long-term datasets and high latitudes (TN > 21 years and > 53.8 °N; TP > 22 years and > 54.5 °N). For model improvements, both the Global NEWS and WorldQual models could benefit from enhanced in-stream nutrient retention/release modules. The Global NEWS model could be further improved with a better chemical weathering module. For the IMAGE-GNM model, refining the soil erosion module is warranted to enhance model performance. Addressing legacy nutrient effects is crucial for all three models. This study provides valuable guidance for selecting and improving nutrient transport models based on specific research needs.

Biological effects of IL-33/ST2 axis on oral diseases: autoimmune diseases and periodontal diseases.

IL-33 is a relatively new member of the IL-1 cytokine family, which plays a unique role in autoimmune diseases, particularly some oral diseases dominated by immune factors. The IL-33/ST2 axis is the main pathway by which IL-33 signals affect downstream cells to produce an inflammatory response or tissue repair. As a newly discovered pro-inflammatory cytokine, IL-33 can participate in the pathogenesis of autoimmune oral diseases such as Sjogren's syndrome and Behcet's disease. Moreover, the IL-33/ST2 axis also recruits and activates mast cells in periodontitis, producing inflammatory chemokines and mediating gingival inflammation and alveolar bone destruction. Interestingly, the high expression of IL-33 in the alveolar bone, which exhibits anti-osteoclast effects under appropriate mechanical loading, also confirms its dual role of destruction and repair in an immune-mediated periodontal environment. This study reviewed the biological effects of IL-33 in autoimmune oral diseases, periodontitis and periodontal bone metabolism, and elaborated its potential role and impact as a disease enhancer or a repair factor.

Integrating physicomechanical and biological strategies for BTE: biomaterials-induced osteogenic differentiation of MSCs.

Large bone defects are a major global health concern. Bone tissue engineering (BTE) is the most promising alternative to avoid the drawbacks of autograft and allograft bone. Nevertheless, how to precisely control stem cell osteogenic differentiation has been a long-standing puzzle. Compared with biochemical cues, physicomechanical stimuli have been widely studied for their biosafety and stability. The mechanical properties of various biomaterials (polymers, bioceramics, metal and alloys) become the main source of physicomechanical stimuli. By altering the stiffness, viscoelasticity, and topography of materials, mechanical stimuli with different strengths transmit into precise signals that mediate osteogenic differentiation. In addition, externally mechanical forces also play a critical role in promoting osteogenesis, such as compression stress, tensile stress, fluid shear stress and vibration, etc. When exposed to mechanical forces, mesenchymal stem cells (MSCs) differentiate into osteogenic lineages by sensing mechanical stimuli through mechanical sensors, including integrin and focal adhesions (FAs), cytoskeleton, primary cilium, ions channels, gap junction, and activating osteogenic-related mechanotransduction pathways, such as yes associated proteins (YAP)/TAZ, MAPK, Rho-GTPases, Wnt/ß-catenin, TGFß superfamily, Notch signaling. This review summarizes various biomaterials that transmit mechanical signals, physicomechanical stimuli that directly regulate MSCs differentiation, and the mechanical transduction mechanisms of MSCs. This review provides a deep and broad understanding of mechanical transduction mechanisms and discusses the challenges that remained in clinical translocation as well as the outlook for the future improvements.

Genetic variations in the bitter taste receptor gene TAS2R38 are related to cigarette smoking behavior in Han Chinese smokers.

BACKGROUND: Smoking behavior is influenced by multiple genes, including the bitter taste gene TAS2R38. It has been reported that the correlation between TAS2R38 and smoking behavior has ethnicity-based differences. However, the TAS2R38 status in Chinese smokers is still unclear. OBJECTIVE: This study aims to investigate the possible relationship between genetic variations in TAS2R38 (A49P, V262A and I296V) and smoking behaviors in the Han Chinese population. METHODS: The haplotype analyses were performed and smoking behavior questionnaire was completed by 1271 individuals. Genetic association analyses for smoking behavior were analyzed using chi-square test. Further, for investigating the molecular mechanism of TAS2R38 variants effect on smoking behavior, we conducted TAS2R38-PAV and TAS2R38-AVI expression plasmids and tested the cellular calcium assay by cigarette smoke compounds stimulus in HEK293. RESULTS: Significant associations of genetic variants within TAS2R38 were identified with smoking behavior. We found a higher PAV/PAV frequency than AVI/AVI in moderate and high nicotine dependence (FTND ≥ 4; X2 = 4.611, 1 df, p = 0.032) and strong cigarette smoke flavor intensity preference (X2 = 4.5383, 1 df, p = 0.033) in participants. Furthermore, in the in vitro cellular calcium assay, total particle matter (TPM), N-formylnornicotine and cotinine, existing in cigarette smoke, activated TAS2R38-PAV but not TAS2R38-AVI-transfected cells. CONCLUSION: Our data highlights that genetic variations in TAS2R38 are related to smoking behavior, especially nicotine dependence and cigarette smoke flavor intensity preference. Our findings may encourage further consideration of the taste process to identify individuals susceptible to nicotine dependence, particularly Han Chinese smokers.

Mussel-Inspired Surface Coating to Stabilize and Functionalize Supramolecular J-Aggregate Nanotubes Composed of Amphiphilic Cyanine Dyes.

We report a mussel-inspired strategy of polydopamine (PDA) coating to stabilize and functionalize J-aggregate nanotubes (NTs) formed by supramolecular self-assembly of an amphiphilic cyanine dye called C8S3 in aqueous media. Optimization of the coating condition by changing the incubation time in a slightly basic media of dopamine with different concentrations leads to conformal wrapping of the PDA layer with controllable thickness on the surface of the NTs. Compared to noncoated pristine C8S3 NTs, these PDA-coated NTs show enhanced stability against dilution, heating, and photobleaching. Moreover, the PDA layer wrapping around the NTs serves as an adhesive for the adsorption of a variety of metal ions and electroless deposition of the metal nanoparticles. Such stabilized and functionalized NT composites may offer a robust synthetic J-aggregate system to mimic the structure and function of light-harvesting complexes and reaction centers in photosynthetic systems.

Flexible light manipulation in non-Hermitian frequency Su-Schrieffer-Heeger lattice.

Recently, studies on non-Hermitian topologic physics have attracted considerable attention. The non-Hermitian skin effect (NHSE), as a remarkable phenomenon in the non-Hermitian lattice, has been demonstrated in coupled ring resonators and photonic mesh lattices. However, there is a scarcity of work on the realization of NHSEs in synthetic dimensions, owing to inaccessible anisotropic coupling. This limits the potential for exploring non-Hermitian topologic physics in on-chip integrated optical systems. In this work, we implement a non-Hermitian Su-Schrieffer-Heeger topologic insulator in the synthetic frequency dimension, and the NHSE and topologic edge state are manifested. Furthermore, we demonstrate that the exotic chiral Zener tunneling can also be realized. Our system provides a versatile platform to explore and exploit non-Hermitian topologic physics on a chip and can have impacts on flexible light manipulation in frequency domains.

[Estimation of Nitrous Oxide Emission from River System Based on Water Discharge and Dissolved Nitrous Oxide Concentration].

Due to increasing active nitrogen pollution loads, river systems have become an important source of nitrous oxide (N2O) in many areas. Due to the lack of monitoring data in many studies as well as the difficulty in estimating intermediate parameters and expressing temporal-spatial variability in current methods, a high level of uncertainty remains in the estimates of riverine N2O emission quantity. Based on the monthly monitoring efforts conducted for 10 sampling sites across the Yonganxi River system in Zhejiang Province from June 2016 to July 2019, the temporal and spatial dynamics of riverine N2O dissolved concentrations ρ(N2O), N2O fluxes, and their influencing factors were addressed. A multiple regression model was then developed for predicating riverine N2O emission flux to estimate annual N2O emission quantity for the entire river system. The results indicated that observed riverine ρ(N2O) (0.03-2.14 µg·L-1) and the N2O fluxes[1.32-82.79 µg·(m2·h)-1] varied by 1-2 orders of magnitude of temporal-spatial variability. The temporal and spatial variability of ρ(N2O) were mainly influenced by the concentrations of nitrate, ammonia, and dissolved organic carbon, whereas the N2O emission fluxes were mainly affected by river water discharges and ρ(N2O). A multiple regression model that incorporates variables of river water discharge and ρ(N2O) could explain 90% of the variability in riverine N2O emission fluxes and has high accuracy. The model estimated N2O emission quantity from the entire Yonganxi River system of 3.67 t·a-1, with 29% from the main stream and 71% from the tributaries. The IPCC default emission factor method might greatly overestimate and underestimate N2O emission quantities for rivers impacted by low and high pressures of human activities, respectively. This study advances our quantitative understanding of N2O emission for the entire river system and provides a reference method for estimating riverine N2O emission with more accuracy.

Bioinspired Molecular Qubits and Nanoparticle Ensembles That Could Be Initialized, Manipulated, and Read Out under Mild Conditions.

Quantum computation and quantum information processing are emerging technologies that have potential to overcome the physical limitation of traditional computation systems. Present quantum systems based on photons, atoms, and molecules, however, all face challenges such as short coherence time, requirement of ultralow temperature and/or high vacuum, and lack of scalability. We report new types of molecular qubits and nanoparticle ensembles based on thermally controllable transformation between J-aggregation and monomeric states of molecular chromophores using pyrrolopyrrole cyanine tethered with polymeric chains such as polycaprolactones as an example. Such supramolecular quantum systems, resembling some feature of light harvesting complexes in photosynthesis, provide new opportunities for manipulating quantum information under mild conditions, which do not require complicated ultracooling and/or high vacuum often involved in superconducting qubits or Rydberg atoms for quantum computation and information processing.

The Coupling Coordination Degree of Economic, Social and Ecological Resilience of Urban Agglomerations in China.

This paper refines the fuzzy logic method, while constructing a theoretical model of the relationship between economic resilience, social resilience and ecological resilience, and evaluates the coupling coordination between the economic-social-ecological resilience of 197 prefecture-level cities in China's urban agglomerations in 2019. Findings include: (1) The mean ecological resilience of China's urban agglomerations in 2019 was the highest, followed by economic and social resilience. (2) Promoting urban agglomerations had higher resilience scores in the three dimensions, especially in the economic dimension. Growing urban agglomerations had low resilience values on the whole, especially economic resilience. (3) The mean coupling coordination degree of economic-social-ecological resilience ranged from near-incoordination to narrow balance. (4) The coupling coordination degree between the two coincided with the positioning of existing urban agglomerations. (5) Economic resilience had the most significant impact on the coupling coordination. Finally, we give differentiated countermeasures to improve the resilience of urban agglomerations. This study aims to contribute to the promotion of urban resilience research, and helps to plan and design more rational urban economic-social-ecological systems, thereby enhancing the ability of cities to cope with any uncertainties and contingencies.

Bacterial Volatile-Mediated Suppression of Root-Knot Nematode (Meloidogyne incognita).

Root-knot nematodes (Meloidogyne spp.) are obligate plant parasites that cause severe economic losses to agricultural crops worldwide. Because of serious health and environmental concerns related to the use of chemical nematicides, the development of efficient alternatives is of great importance. Biological control through exploiting the potential of rhizosphere microorganisms is currently accepted as an important approach for pest management in sustainable agriculture. In our research, during screening of rhizosphere bacteria against the root-knot nematodes Meloidogyne incognita, Ochrobactrum pseudogrignonense strain NC1 from the rhizosphere of healthy tomatoes showed strong nematode inhibition. A volatile nematicidal assay showed that the cell-free fermentation filtrate in the first-row wells of 12-well tissue culture plates caused M. incognita juvenile mortality in the second-row wells. Gas chromatography-mass spectrometry analysis revealed that dimethyl disulfide (DMDS) and benzaldehyde were the main volatile compounds produced by strain NC1. The nematicidal activity of these compounds indicated that the lethal concentration 50 against the M. incognita juveniles in the second-row wells and the fourth-row wells were 23.4 µmol/ml and 30.7 µmol/ml for DMDS and 4.7 µmol/ml and 15.2 µmol/ml for benzaldehyde, respectively. A greenhouse trial using O. pseudogrignonense strain NC1 provided management efficiencies of root-knot nematodes of 88 to 100% compared with the untreated control. This study demonstrated that nematode-induced root-gall suppression mediated by the bacterial volatiles DMDS and benzaldehyde presents a new opportunity for root-knot nematode management.

Strong single-photon optomechanical coupling in a hybrid quantum system.

Engineering strong single-photon optomechanical couplings is crucial for optomechanical systems. Here, we propose a hybrid quantum system consisting of a nanobeam (phonons) coupled to a spin ensemble and a cavity (photons) to overcome it. Utilizing the critical property of the lower-branch polariton (LBP) formed by the ensemble-phonon interaction, the LBP-cavity coupling can be greatly enhanced by three orders magnitude of the original one, while the upper-branch polariton (UBP)-cavity coupling is fully suppressed. Our proposal breaks through the condition of the coupling strength less than the critical value in previous schemes using two harmonic oscillators. Also, strong Kerr effect can be induced in our proposal. This shows our proposed approach can be used to study quantum nonlinear and nonclassical effects in weakly coupled optomechanical systems.

Functional Polymers and Polymer-Dye Composites for Food Sensing.

The sensitive, safe, and portable detection of food spoilage is becoming unprecedentedly important because it is closely related to the public health and economic development, particularly given the globalization of food supply chain. However, the existing approaches for food monitoring are still limited to meet these requirements. To address this challenge, much research has been done to develop an ideal food sensor that can indicate food quality in real-time in a sensitive and reliable way. So far, many sensors such as time-temperature indicators, smart trademarks, colorimetric tags, electronic noses, and electronic tongues, have been developed and even commercialized. In this feature article, the recent progress of food sensors based on functional polymers, including the molecular design of polymer structures, sensing mechanisms, and relevant processing techniques to fabricate a variety of food sensor devices is reviewed.

Effects of Ginkgo biloba on Early Decompression after Spinal Cord Injury.

Spinal cord injury (SCI) is a severe trauma of the central nervous system characterized by high disability and high mortality. Clinical progress has been achieved in understanding the pathological mechanism of SCI and its early treatment, but the results are unsatisfactory. In China, increasing attention has been paid to the role of traditional Chinese medicine in the treatment of SCI. In particular, extracts from the leaves of Ginkgo biloba (maidenhair tree), which have been reported to exert anti-inflammatory and antioxidant properties and repair a variety of active cellular damage, have been applied therapeutically for centuries. In this study, we established a rat SCI model to investigate the effects of Ginkgo biloba leaves on decompression at different stages of SCI. The application of Ginkgo biloba leaves during the decompression of SCI at different time points, the neurological recovery of SCI, and the underlying molecular mechanism were explored. The findings provide reliable experimental data that reveal the mechanism of GBI (Ginkgo biloba injection) in the clinical treatment of SCI.

Spin squeezing of 1011 atoms by prediction and retrodiction measurements.

The measurement sensitivity of quantum probes using N uncorrelated particles is restricted by the standard quantum limit1, which is proportional to [Formula: see text]. This limit, however, can be overcome by exploiting quantum entangled states, such as spin-squeezed states2. Here we report the measurement-based generation of a quantum state that exceeds the standard quantum limit for probing the collective spin of 1011 rubidium atoms contained in a macroscopic vapour cell. The state is prepared and verified by sequences of stroboscopic quantum non-demolition (QND) measurements. We then apply the theory of past quantum states3,4 to obtain spin state information from the outcomes of both earlier and later QND measurements. Rather than establishing a physically squeezed state in the laboratory, the past quantum state represents the combined system information from these prediction and retrodiction measurements. This information is equivalent to a noise reduction of 5.6 decibels and a metrologically relevant squeezing of 4.5 decibels relative to the coherent spin state. The past quantum state yields tighter constraints on the spin component than those obtained by conventional QND measurements. Our measurement uses 1,000 times more atoms than previous squeezing experiments5-10, with a corresponding angular variance of the squeezed collective spin of 4.6 × 10-13 radians squared. Although this work is rooted in the foundational theory of quantum measurements, it may find practical use in quantum metrology and quantum parameter estimation, as we demonstrate by applying our protocol to quantum enhanced atomic magnetometry.