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The fluorescence quenching phenomenon commonly found in two-dimensional COFs is due to either the strong interlayer π-π stacking or the non-radiative decay caused by intramolecular rotation. Here, we report a rigidity-flexibility balance strategy for constructing highly photoluminescent 2D COF nanosheets

Negative effects of long‐term overgrazing have been seriously, grasslands temporal stability is an important ecological concern we need to research. Here, we performed a 12‐year‐long (2007–2018) two‐factor controlled experiment on Kobresia humilis meadow on the Tibetan Plateau. The manipulations included three clipping levels (no clipping, NC; moderate clipping, MC; heavy clipping, HC) and two fertilization levels (no fertilization, NF; fertilization, F). Our results revealed that the two clipping manipulations significantly increased the temporal stability of alpine meadow communities, whose significant increase was more pronounced under the MC than HC treatment. Species asynchrony had a significant positive correlation with species abundance along with compound community gradient. Moreover, asynchrony effects, portfolio effects, and facilitation interactions were all present in the communities under the six types of experimental treatment combinations. Additionally, a selection effect was detected in the compound communities, demonstrating characteristics that are common to different mechanisms. There were no significant differences in the effects of these mechanisms on community temporal stability between the NC–NF and MC–NF interactive communities. The portfolio effects predominated when clipping intensity was moderate under both fertilization and nonfertilization conditions. By contrast, in the compound communities, the selection effect predominated. In summary, we conclude that in meadow communities that undergo clipping and fertilization disturbances, facilitation interactions and weak interactions make a greater contribution toward maintaining their temporal stability., Under six experimental conditions of clipping and fertilization levels, we found that fertilization, as well as heavy and especially moderate clipping intensity, significantly increased the temporal stability of K. humilis. Asynchrony effects, portfolio effects, and facilitation interactions were all present under the six experimental treatment conditions in this study. Clipping mainly increased community temporal stability via the asynchrony effect, whereas this increase under fertilization treatment was mainly owing to facilitation and weak interactions.

Platelet homeostasis is essential for vascular integrity and immune defense. While the process of platelet formation by fragmenting megakaryocytes (thrombopoiesis) has been extensively studied, the cellular and molecular mechanisms required to constantly replenish the pool of megakaryocytes by their progenitor cells (megakaryopoiesis) remains unclear. Here we use intravital 2 photon microscopy to track individual megakaryopoiesis over days. We identify plasmacytoid dendritic cells (pDCs) as crucial bone marrow niche cells that regulate megakaryopoiesis. pDCs monitor the bone marrow for platelet-producing megakaryocytes and deliver IFN-α to the megakaryocytic niche to trigger local on-demand proliferation of megakaryocyte progenitors. This fine-tuned coordination between thrombopoiesis and megakaryopoiesis is crucial for megakaryocyte and platelet homeostasis in steady state and stress. However, uncontrolled pDC function within the megakaryocytic niche is detrimental. Accordingly, we show that pDCs activated by SARS-CoV2 drive inappropriate megakaryopoiesis associated with thrombotic complications. Together, we uncover a hitherto unknown megakaryocytic bone marrow niche maintained by the constitutive delivery of pDC-derived IFN-α.

The capture of highly radiotoxic 90Sr from an acidic waste solution during used fuel reprocessing and environmental remediation in a nuclear accident is desirable and challenging. Herein, we show a metal organic framework material (SNU-200) functionalized with an 18-crown-6-ether, whose specific binding site with an excellent affinity toward strontium leads to excellent Sr2+ adsorption capability under acidic conditions. This material exhibits a high adsorption capacity (44.37 mg g−1 at pH = 3), remarkable affinity (Kd = 3.63 × 104 mL g−1) and ultrahigh selectivity in the presence of interfering coexisting ions such as Na+, K+, Cs+, Mg2+, and Ca2+.

Aiming at elevating Scenedesmus obliquus biofilm growth from the perspectives of CO2 transfer enhancement and light delivery optimization, a membrane-based photobioreactor with built-in optical fib...

With the development of quantum theory, traditional encryption algorithms are facing enormous challenges. Once quantum computers are available, existing encryption systems will no longer be secure. The lattice cipher is proven by theory to be a new type of encryption scheme, which can resist quantum algorithm. It has the property of fast computing speed and small space occupation, hence, it has become a hot issue in today??s research. The identity-based encryption scheme can improve the utilization of storage space and facilitate user public key management. Consequently, this paper based on the hard problem of learning with errors (LWE), constructs an identity-based matrix encryption scheme at first, then applies the improved key switching technology to reduce the dimension of homomorphic ciphertext to normal, and uses the mode conversion technique to reduce noise, realizing matrix homo-morphic operation, and getting an identity-based matrix (level) fully homomorphic encryption scheme. The scheme uses matrices as the storage structure, which has greatly improved the processing capability compared to other single-bit schemes. The scheme not only satisfies the addition and Hadamard product of the matrix, but also supports matrix dot multiplication. The experimental results show that compared with other methods, the improved key switching technology in this paper inputs less noise. Through the difficulty of the LWE problem, it is proven that the scheme satisfies IND-sID-CPA (indistinguishability-selective identity-chosen plaintext attack).

In recent years, solar steam generation technology has received widespread attention in seawater desalination, but existence of some problems, namely difficulty in salt cleaning and high expense, limited it further development. Herein, in this work, a carbon black gauze membrane (CBGM), with low cost and easy to clean properties, was developed by stacking macroporous membrane to construct 3D optical absorption holes, which were favorable to an enhancement of light absorption. The 4-layer CBGM evaporation device displayed an improved solar steam generation performance, which was corresponded to the evaporation rate of 1.60 kg m−2h−1 and the evaporation efficiency of 96.0% under 1 kW m−2, respectively. Likewise, the 4-layer CBGM evaporation device exhibited superior recyclability, long life and excellent desalination performance, as well as was able to effectively produce potable freshwater from seawater. Consequently, the CBGM was regarded as a promising alternative for high-efficiency solar-driven seawater desalination.

Microalgae-based nutrients recovery from liquid anaerobic digestate of swine manure has been a hotspot in recent decades. Nevertheless, in consideration of the high NH

User data on the Internet are extremely easy to leak, and the anonymity and security issues of users need to be resolved. The pseudonym system can make users remain anonymous in network communication, but there are risks of collusion between authentication agencies and domain management agencies and a slow response to the offending user. Aiming at this problem, a pseudonym signature scheme involving trusted third parties is proposed in this paper. The user first applies to the certificate authority for a license permitting the use of a pseudonym, then uses the license to apply for the pseudonym certificate from the domain authority, and uses the pseudonym to construct a pseudonym signature in the domain. Finally, users with illegal operations are quickly detected by tracking center (trusted third party), and the certificate authority will handle the corresponding processing. The proposed scheme guarantees the anonymity of users better by using double pseudonyms, reduces the operation cost of the certificate authority, improves the threshold of the system, has fast response ability in acquiring the real identity of users who violate the rules, and reduces the potential loss of the system caused by users illegal operations.

Thermal energy storage (TES) is among the most powerful tools to alleviate the risk of fossil energy depletion. Latent heat density and thermal conductivity are the two most important parameters to evaluate the performance of TES materials. In this work, for the first time, we embed knitting aryl network polymers (KAPs) on the skeleton of copper foam (CF) in a biomimetic protocol, where the preparation process is inspired by the growing process of a natural coral and the obtained phase change material (PCM)-holding medium exhibits a bird nest-type morphology. Excellent energy storage performance was determined, where the thermal conductivity was up to 55.37 W m−1 K−1 and the encapsulation rate could reach 62.1% without the observation of any enthalpy attenuation even after a 300 energy charging and releasing cyclization, due to the relatively high surface area, i.e., 1079.1 m2 g−1 and high thermal conductivity of the copper skeleton inside. Further study revealed the good applicable properties in terms of shape adjustability, light-to-thermal and light-to-electric conversion.

Solar water evaporation is universally considered as an effective method to alleviate the freshwater shortage worldwide. A series of three-dimensional, salt-resistant evaporators have been brought out to improve the evaporation performance. However, little attention was paid to the collection of salt from seawater and high salinity brine. In this work, a carbon black polyvinyl alcohol (PVA) sponge was prepared to harvest light using a physical adsorption method to load carbon black on the PVA sponge. The experimental results showed that optimal light absorption (97.8%) and evaporation rate (1.60 kg m

To rapidly obtain the complete characterization information of pulse signals and to verify the sensitivity and validity of pulse signals in the clinical diagnosis of related diseases. In this paper, an improved PNCC method is proposed as a supplementary feature to enable the complete characterization of pulse signals. In this paper, the wavelet scattering method is used to extract time-domain features from impulse signals, and EEMD-based improved PNCC (EPNCC) is used to extract frequency-domain features. The time–frequency features are mixed into a convolutional neural network for final classification and recognition. The data for this study were obtained from the MIT-BIH-mimic database, which was used to verify the effectiveness of the proposed method. The experimental analysis of three types of clinical symptom pulse signals showed an accuracy of 98.3% for pulse classification and recognition. The method is effective in complete pulse characterization and improves pulse classification accuracy under the processing of the three clinical pulse signals used in the paper.

Luminescent covalent organic frameworks (COFs) find promising applications in chemical sensing, photocatalysis, and optoelectronic devices, however, the majority of COFs are non or weakly emissive owing to the aggregation-caused quenching (ACQ) or the molecular thermal motion-based energy dissipation. Here, we report a previously unperceived approach to improve luminescence performance of COFs by introducing isotope effect, which is achieved through substitution of hydrogen from high-frequency oscillators X-H (X=O, N, C) by heavier isotope deuterium. Combining the "bottom-up" and in situ deuteration methods generates the first deuterated COF, which exhibits an impressively 19-fold enhancement in quantum yield over that of the non-deuterated counterpart. These results are interpreted by theoretical calculations as the consequence of slower C/N-D and OD⋅⋅⋅O vibrations that impede the nonradiative deactivation process. The proposed strategy is proved applicable to many other types of emissive COFs.

The all-in-one solar steam generation device renders a feasible technical support for freshwater supply in arid areas, where traditional large-scale desalination cannot be applied. In this work, we designed and assembled a paper-based integrated evaporation device (IED) for efficient solar steam generation, in which the self-hardening polyurethane foam was ingeniously fixed on the carbon nanotube (CNT) loaded filter paper connecting with four paper belts to perfectly integrate light absorption, water supply and thermal insulation into one device. Moreover, the effects of CNT concentration and illumination intensity on evaporation performance were experimentally investigated. The results showed that the maximum thermal conversion efficiency of the IED was as high as 88.1% at 1 kW m−2. Our research indicated that the IED as an easily-enlarged and all-in-one evaporation device was one of the ideal choices for applications in solar steam generation and provided a new resource for seawater desalination.

High-efficiency solar steam generation through interfacial solar heating of the membrane is a promising approach to alleviate the shortage of freshwater resources. In this work, we developed a membrane distillation device (MDD), consisting of a carbon nanotube (CNT) membrane as solar absorption layer, a qualitative filter paper as water transmission pipeline and an aerogel blanket as thermal insulator to achieve efficient solar harvesting and heat localization for enhancing water evaporation. The results illustrated that the MDD achieved a thermal conversion efficiency of up to 84.6% at a light intensity of 1 kW m−2 and showed superior cyclic stability for 10 cycles test. As a consequence, the self-assembled and reusable MDD was suitable as a promising candidate for seawater desalination.

Activated carbons (ACs) derived from biomass have become one of the most promising electrode materials for supercapacitors due to their reproducibility and low cost. In this study, peanut shell is used as the precursor to prepare AC via one-step synthesis method activated by ZnCl2, FeCl3 and their mixture in N2 atmosphere at 700 °C. The characteristics and structure of the obtained ACs were studied by SEM, HR-TEM, BET, FT-IR, XRD and Raman spectroscopy. The prepared AC materials showed high specific surface area and large amount of micropores, and the maximum specific surface area reached 1481.59 m2/g. The etching effect of iron oxide and zinc chloride on the carbon skeleton facilitated the formation of micropores. The XRD pattern and Raman spectra indicated that all samples were amorphous carbons with some graphitic crystalline structures. In addition, FT-IR analysis illustrated that the surface of AC materials possessed a large number of oxygen-containing functional groups, which were beneficial to their electrochemical performance. From the electrochemical performance of the AC materials, it was observed that better electrochemical properties were achieved at a weight ratio of biomass to activator of 2:1 in comparison with 0.8:1 and 4:1 for all the activators. The obtained AC showed a high specific capacitance of 239.88 F/g at the current density of 0.5 A/g in 1 M Na2SO4 electrolyte and exhibited excellent cycling performance with 94.55% capacity retention after 5000 cycles.

Catalytic performance of Cu and Zn catalysts was investigated during rice husk (RH) high-temperature pyrolysis under isothermal conditions in a micro-fluidized bed reactor. The results showed that the presence of Cu and Zn evidently influenced the release characteristics and conversion of the gas components. The impregnated Cu promoted the conversion of H2, CH4, CO and CO2, while Zn showed positive catalytic effect on the conversion of H2, CH4 and CO2 and negative effect on the conversion of CO. The X-ray diffraction patterns of the residue chars revealed that metallic copper nanoparticles (Cu0) were formed during Cu impregnated biomass pyrolysis. Textural characterization and SEM images showed that the impregnation of Cu and Zn, particularly Zn, promoted the generation of micropores and mesopores, with the pore sizes predominantly at around 1.3 nm and 3.9 nm. Reaction kinetics for generating these gases was studied based on model fitting method, and the most probable reaction mechanism was obtained based on the relative error between experimental and calculated conversion data. The resulting apparent activation energies were 85.08, 12.56, 49.72 and 38.37 kJ/mol for the formation of H2, CO, CH4 and CO2 from pure RH pyrolysis. The presence of Cu decreased the forming activation energies of the four gases, and Zn decrease the forming activation energies of H2, CH4 and CO2 while increased the value for the formation of CO.

The effects of human disturbance on the stability of alpine meadow communities, their diversity–stability relationship, and the underlying mechanisms are still not fully understood. Here, we performed a 12-year-long (2007–2018) two-factor (2 × 3) controlled experiment on Kobresia humilis on the Tibetan Plateau. The manipulations included three clipping levels (no clipping, NC; moderate clipping, MC; heavy clipping, HC) and two fertilization levels (no fertilization, NF; fertilization, F). Our results revealed that the two clipping manipulations significantly increased the temporal stability of alpine meadow communities, whose significant increase was more pronounced under the MC than HC treatment. Moreover, asynchrony effects, portfolio effects, and facilitation interactions were all present in the communities under the six types of experimental treatment combinations. Additionally, a selection effect was detected in the compound communities, demonstrating characteristics that are common to different mechanisms. There were no significant differences in the effects of these mechanisms on community temporal stability between the NC–NF and MC–NF interactive communities. The portfolio effects predominated when clipping intensity was moderate under both fertilization and non-fertilization conditions. By contrast, in the compound communities, the selection effect predominated. In summary, we conclude that in meadow communities that undergo clipping and fertilization disturbances, facilitation interactions and weak interactions make a greater contribution toward maintaining their temporal stability.

Background The pericarp of citrus in rutaceae is rich in flavonoids that may possess diverse biological activities. Some citrus flavonoids have been used as natural bitterness inhibitors; however, many citrus flavonoid analogues that possess merit taste amelioration functions have not been reported with respect to utilization in food industry. Results The effects of 12 citrus flavonoids on the inhibition of the bitter taste of naringin, quinine hydrochloride and stevioside were evaluated both by a sensory panel and electronic tongue analysis. Among the flavonoid compounds evaluated, both neohesperidin dihydrochalcone (NHDC) and neodiosmin were identified to show an excellent bitterness inhibition effect on all three bitterness vehicles tested. The results of the electronic tongue evaluation also showed that the addition of neodiosmin, NHDC or hesperidin dihydrochalcone-7-o-glucoside (HDC-7-G) was able to reduce significantly the bitterness response value of quinine hydrochloride, which is consistent with the sensory panel evaluation. Structure-activity relationship analysis found that the 7-linked neohesperidosyloxy group in the A-ring of the citrus flavonoid skeleton has the best bitterness inhibition effect. In addition, a ternary mixture of NHDC, neodiosmin and naringin, and neodiosmin/β-cyclodextrin was formulated and it demonstrated, for the first time in the flavor improvement of citrus fruit wine, an enhancement of sweetness and a reduction of bitter taste. Conclusion Twelve citrus flavonoids were found to inhibit the bitter taste of naringin, quinine hydrochloride and stevioside. With respect to the structure-activity relationship analysis, it was found that the 7-linked neohesperidosyloxy group in the A-ring of the citrus flavonoid skeleton possessed the best bitterness inhibition effect. © 2021 Society of Chemical Industry.

Background: Paraganglioma (PGL) is a rare neuroendocrine tumour derived from the extra- adrenal gland that is also known as ectopic pheochromocytoma (PHEO). The typical clinical symptoms are paroxysmal hypertension with headache, sweating and palpitation. However, PGL with abnormal glucose metabolism as the main manifestation is rare.Case Presentation: In this case, the patient had a history of diabetes for 13 years and showed persistently increased blood glucose. The application of multiple hypoglycaemic drugs to control the patient’s blood glucose was ineffective, and a limited effect of high-dose insulin was observed. This patient underwent a contrast-enhanced computed tomography scan(CT),showing a soft tissue density shadow (3.2×2.4cm) with clear edges and slight enhancement in the medial side of inferior vena cava. Exploratory laparotomy was performed and significant blood pressure changes were observed when the tumourwas removed during the operation. The patient’s blood glucose decreased significantly and hypoglycaemiawas noted when the patient’s original dose of insulin was maintained. The patient recovered uneventfully and was discharged after the operation.Conclusions: Hyperglycaemia caused by PGL is rare in the clinic; therefore, it is necessary to pay attention to the relevant blood glucose indexes during the preoperative examination and diagnosis process to improve the examination process and further assist in the preoperative diagnosis of PGL. It is necessary to pay attention to changes in blood pressure during and after the operation to avoid hypoglycaemia. Lifetime follow up is necessary after the operation.

Rheumatoid arthritis (RA) is a worldwide autoimmune disease. The study of its aetiology and mechanism has always been a focus topic in medicine. This research was designed to investigate the effect of E3 ubiquitin ligase tripartite motif protein 32 (TRIM32) in rheumatoid arthritis (RA). We found in fibroblast-like synoviocytes (FLS) of RA patients, the expression of TRIM32 was significantly increased compared with its expression in osteoarthritis (OA) patients FLS. A widely used pro-inflammatory stimuli tumour necrosis factor-alpha (TNF-α) was found to promote TRIM32 expression in a time-dependent manner. Furthermore, we observed that overexpression of TRIM32 aggravated the production of pro-inflammatory cytokines in FLS, silencing of TRIM32 showed the consistent results. In addition, TRIM32 was found to activate nuclear factor κB (NF-κB) signalling pathway, and TRIM32 could interact with TNF receptor-associated factor 2 (TRAF2) to promote the K63-linked polyubiquitination of TRAF2 in RA-FLS. In conclusion, we suggested that TRIM32 as a positive regulator of inflammatory responses in RA-FLS.

The work aims to investigate an effective method of catalytic reforming of tar during biomass high-temperature pyrolysis using rice husk char (RHC) and metal impregnated (Fe, Cu and K) char in a dual-stage reactor. The char and char-supported catalysts exhibited high catalytic performance, in terms of the high tar conversion efficiencies of 77.1% for RHC, 82.7% for K-RHC, 92.6% for Fe-RHC and 90.6% for Cu-RHC at 800 °C. Moreover, K-RHC and Cu-RHC catalysts after three cycles still exhibited high activity for tar removal. The catalytic tar conversion by char or char-supported catalysts contributes to improving the yield of syngas, particularly the combustible gases of H2, CO and CH4, corresponding to the syngas yield increasing from 196.6 mL/g for thermal reforming to 269.6 mL/g for K-RHC, 274.9 mL/g for Cu-RHC and 342.7 mL/g for Fe-RHC at 800 °C, respectively. The results from GC–MS analysis illustrated that the addition of char and char-supported catalysts promoted the transformation of larger polycyclic aromatic hydrocarbons into lighter tar compounds, leading to an increase in the proportion of single-ring tars. XRD results indicated that the most active phases of the fresh K-RHC, Cu-RHC and Fe-RHC for tar cracking and reforming were KCl, Cu and Fe, respectively. Textural characterization showed the addition of Fe and Cu was in favor of producing highly porous carbon materials and led to the increase in specific surface area and total pore volume.

High ash-containing paper sludge which is rich in various metal oxides is employed in herb residue pyrolysis to enhance the yield of fuel gas and reduce tar yield in a drop tube fixed bed reactor. Effects of heat treatment temperature and blending ratio of paper sludge on the yields and composition of pyrolysis products (gas, tar and char) were investigated. Results indicate that paper sludge shows a significantly catalytic effect during the pyrolysis processes of herb residue, accelerating the pyrolysis reactions. The catalytic effect resulted in an increase in gas yield but a decrease in tar yield. The catalytic effect degree is affected by the paper sludge proportions, and the strongest catalytic effect of paper sludge is noted at its blending ratio of 50%. At temperature lower than 900 °C, the catalytic effect of paper sludge in the pyrolysis of herb residue promotes the formation of H2 and CO2, inhibits the formation of CH4, but shows slight influence on the formations of CO, while the formation of the four gas components was all promoted at 900 °C. SEM results of residue char show that ash particles from paper sludge adhere to the surface of the herb residue char after pyrolysis, which may promote the pyrolysis process of herb residue for more gas releasing. FT-IR results indicate that most functional groups disappear after pyrolysis. The addition of paper sludge promotes deoxidisation and aromatization reactions of hetero atoms tars, forming heavier polycyclic aromatic hydrocarbons and leading to tar yield decrease.

The co-pyrolysis characteristics of Zhundong lignite and pine sawdust were investigated in a thermogravimetric analyzer and a fixed bed reactor. This study found that the obtained activation energies were generally lower than the calculated values. Particularly in the conversion range of 0.2–0.6, most of the relative deviation values was lower than −10% for the blends, indicating positive synergistic effect between Zhundong lignite and pine sawdust in volatiles release during non-isothermal pyrolysis. From the isothermal pyroylysis in the fixed bed reactor, the experimental values of gas yield were greater than the calculated, while both experimental tar and char yields became lower. Pronounced synergy effect occurred at ZD and PS mass ratio of 1:1 and 2:1 for tar and gas product, indicating that enough hydrogen-donors could be provided to promote degradation reactions. The experimental yields of four main gas components, CO, H2, CO2 and CH4, were all higher than that of the calculated values. SEM results indicated both Zhundong lignite and pine sawdust residue chars became more porous, and metals salt in Zhundong lignite volatilized and condensed on the surface of Zhundong lignite and pine sawdust, which may perform as catalyst during co-pyrolysis.

Isothermal pyrolysis of rice husk catalyzed by iron and nickel was conducted in a microfluidized bed reactor to investigate the forming characteristics and kinetics of the main gas components. Results indicated that both Fe and Ni showed a catalytic effect on the releasing behavior of gaseous products during rice husk pyrolysis. The forming reaction rate of H2 and CO2 was significantly promoted with the addition of Fe or Ni, while that of CH4 was inhibited. For CO, Ni showed a positive effect while Fe showed a negative effect on its forming rate. The char evolution of rice husk was also influenced by the presence of Fe and Ni from the SEM-EDX and BET results. The model fitting method was used to calculate the kinetics of gas releasing to further investigate the effect of Fe and Ni, and the most probable reaction mechanism was obtained based on the relative error between experimental and calculated conversion fraction. Corresponding to the changing trend of reaction rate, the obtained activation energies f...