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1.
Nature ; 604(7904): 72-79, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35388196

RESUMO

Covalent organic frameworks (COFs) are distinguished from other organic polymers by their crystallinity1-3, but it remains challenging to obtain robust, highly crystalline COFs because the framework-forming reactions are poorly reversible4,5. More reversible chemistry can improve crystallinity6-9, but this typically yields COFs with poor physicochemical stability and limited application scope5. Here we report a general and scalable protocol to prepare robust, highly crystalline imine COFs, based on an unexpected framework reconstruction. In contrast to standard approaches in which monomers are initially randomly aligned, our method involves the pre-organization of monomers using a reversible and removable covalent tether, followed by confined polymerization. This reconstruction route produces reconstructed COFs with greatly enhanced crystallinity and much higher porosity by means of a simple vacuum-free synthetic procedure. The increased crystallinity in the reconstructed COFs improves charge carrier transport, leading to sacrificial photocatalytic hydrogen evolution rates of up to 27.98 mmol h-1 g-1. This nanoconfinement-assisted reconstruction strategy is a step towards programming function in organic materials through atomistic structural control.

2.
Med Res Rev ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711187

RESUMO

Previously, lysosomes were primarily referred to as the digestive organelles and recycling centers within cells. Recent discoveries have expanded the lysosomal functional scope and revealed their critical roles in nutrient sensing, epigenetic regulation, plasma membrane repair, lipid transport, ion homeostasis, and cellular stress response. Lysosomal dysfunction is also found to be associated with aging and several diseases. Therefore, function of macroautophagy, a lysosome-dependent intracellular degradation system, has been identified as one of the updated twelve hallmarks of aging. In this review, we begin by introducing the concept of lysosomal quality control (LQC), which is a cellular machinery that maintains the number, morphology, and function of lysosomes through different processes such as lysosomal biogenesis, reformation, fission, fusion, turnover, lysophagy, exocytosis, and membrane permeabilization and repair. Next, we summarize the results from studies reporting the association between LQC dysregulation and aging/various disorders. Subsequently, we explore the emerging therapeutic strategies that target distinct aspects of LQC for treating diseases and combatting aging. Lastly, we underscore the existing knowledge gap and propose potential avenues for future research.

3.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843049

RESUMO

The development of a catalytic method for stereogenic carbon center formation holds immense significance in organic synthesis. Transition-metal-catalyzed cross-coupling reaction has been regarded as a straightforward and efficient tool for stereoselectively forging C-C bond. Nevertheless, the creation of acyclic all-carbon quaternary-containing vicinal stereocenters remains notoriously challenging within the domain of cross-coupling chemistry despite their prominence in various bioactive small molecules. Herein, we describe a palladium-catalyzed asymmetric multicomponent cross-coupling of trisubstituted alkene with aryl diazonium salts and arylboronic acids to realize the formation of tertiary-quaternary carbon centers with high regio-, distereo-, and enantioselectivity. Specifically, the precise manipulation of the stereoconfiguration of trisubstituted alkenes enables the divergent stereoselective cross-coupling reaction, thus allowing for the facile construction of all four enantiomers. Harnessing the ligand-swap strategy involving a chiral bisoxazoline and an achiral fumarate individually accelerates the enantioselective migratory insertion and reductive elimination step in the cross-coupling process, as supported by density functional theory (DFT) calculations, thus obviating the requirement for a neighboring directing group within the internal olefin skeleton.

4.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842422

RESUMO

Photocatalytic covalent organic frameworks (COFs) are typically constructed with rigid aromatic linkers for crystallinity and extended π-conjugation. However, the essential hydrophobicity of the aromatic backbone can limit their performances in water-based photocatalytic reactions. Here, we for the first time report the synthesis of hydrophilic COFs with aliphatic linkers [tartaric acid dihydrazide (TAH) and butanedioic acid dihydrazide] that can function as efficient photocatalysts for H2O2 and H2 evolution. In these hydrophilic aliphatic linkers, the specific multiple hydrogen bonding networks not only enhance crystallization but also ensure an ideal compatibility of crystallinity, hydrophilicity, and light harvesting. The resulting aliphatic linker COFs adopt an unusual ABC stacking, giving rise to approximately 0.6 nm nanopores with an improved interaction with water guests. Remarkably, both aliphatic linker-based COFs show strong visible light absorption, along with a narrow optical band gap of ∼1.9 eV. The H2O2 evolution rate for TAH-COF reaches up to 6003 µmol h-1 g-1, in the absence of sacrificial agents, surpassing the performance of all previously reported COF-based photocatalysts. Theoretical calculations reveal that the TAH linker can enhance the indirect two-electron oxygen reduction reaction for H2O2 production by improving the O2 adsorption and stabilizing the *OOH intermediate. This study opens a new avenue for constructing semiconducting COFs using nonaromatic linkers.

5.
Angew Chem Int Ed Engl ; 63(16): e202401260, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372399

RESUMO

Formamidinium lead iodide (FAPbI3) represents an optimal absorber material in perovskite solar cells (PSCs), while the application of FAPbI3 in inverted-structured PSCs has yet to be successful, mainly owing to its inferior film-forming on hydrophobic or defective hole-transporting substrates. Herein, we report a substantial improvement of FAPbI3-based inverted PSCs, which is realized by a multifunctional amphiphilic molecular hole-transporter, (2-(4-(10H-phenothiazin-10-yl)phenyl)-1-cyanovinyl)phosphonic acid (PTZ-CPA). The phenothiazine (PTZ) based PTZ-CPA, carrying a cyanovinyl phosphonic acid (CPA) group, forms a superwetting hole-selective underlayer that enables facile deposition of high-quality FAPbI3 thin films. Compared to a previously established carbazole-based hole-selective material (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl)phosphonic acid (MeO-2PACz), the crystallinity of FAPbI3 is enhanced and the electronic defects are passivated by the PTZ-CPA more effectively, resulting in remarkable increases in photoluminescence quantum yield (four-fold) and Shockley-Read-Hall lifetime (eight-fold). Moreover, the PTZ-CPA shows a larger molecular dipole moment and improved energy level alignment with FAPbI3, benefiting the interfacial hole-collection. Consequently, FAPbI3-based inverted PSCs achieve an unprecedented efficiency of 25.35 % under simulated air mass 1.5 (AM1.5) sunlight. The PTZ-CPA based device shows commendable long-term stability, maintaining over 90 % of its initial efficiency after continuous operation at 40 °C for 2000 hours.

6.
J Am Chem Soc ; 145(24): 12951-12966, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37276078

RESUMO

Circularly polarized luminescence (CPL) is attracting much interest because it can carry extensive optical information. CPL shows left- or right-handedness and can be regarded as part of high-level visual perception to supply an extra dimension of information with regard to regular light. A key to meeting the needs for practical applications is to develop the emerging field of ultra-dissymmetric CPL. Chiral liquid crystal (LC) assemblies─otherwise referred to as cholesteric liquid crystals (CLCs)─are essentially organized helical superstructures with a highly ordered one-dimensional orientation, and distinctly superior to regular helical supramolecules. CLCs can achieve a perfect equilibrium of molecular short-range interaction and long-range orientational order, enabling molecule-scale chirality on a helical pitch and observable scale. LC assembly could be an ideal strategy for amplifying chirality, making it accessible to ultra-dissymmetric CPL. Herein, we focused on some basic but important issues regarding CPL: (i) How can CPL be created from chiral dyes? (ii) Is the chirality of luminescent dyes an essential factor for the generation of CPL? That is, can all chiral dyes emit CPL and vice versa? (iii) How can CPL be transferred within intermolecular systems, and what principles of CPL transmission should be followed? Given these queries and our work, in this Perspective we discuss the generation, transmission, and modulation of CPL with chiral LC assembly, aiming to design and build up novel chiroptical materials. Recent applications of CPL-active LC microstructures in three-dimensional displays, circularly polarized lasers, and asymmetric catalysis are also discussed.

7.
Chembiochem ; 24(18): e202300321, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37218114

RESUMO

Development of "ultrahigh contrast" fluorogenic probes for trapping alkaline phosphatase (ALP) activities in human serum is highly desirable for clinical auxiliary diagnosis for hepatobiliary diseases. However, the intrinsic dilemma of incomplete ionization of intramolecular charge transfer (ICT)-based ALP fluorophores and autofluorescence interference of serum result in low sensitivity and accuracy. Given that unique halogen effects could lead to a drastic decrease in the pKa value and a significant enhancement in the fluorescence quantum yield, herein we report an enzyme-activatable near-infrared probe based on a difluoro-substituted dicyanomethylene-4H-chromenep for achieving fluorescent quantification of human serum ALP. Rational design strategy is demonstrated by altering the substituted halogen groups to well regulate the pKa for meeting the physiological precondition. Owing to the complete ionization at pH 7.4 with tremendous fluorescence enhancement, the difluoro-substituted DCM-2F-HP manifests a linear relationship between the emission intensity and ALP concentration in both solution and serum samples. Along with measuring 77 human serum samples, the DCM-2F-HP based fluorescence method not only exhibits significant correlations with clinical colorimetry, but also distinguishes ALP patients from healthy volunteers, as well as assessing the progress of liver disease, thus providing a potential toolbox for quantitatively detecting ALP and warning the stage of hepatopathy.


Assuntos
Fosfatase Alcalina , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/química , Fluorescência , Fígado
8.
Acc Chem Res ; 55(21): 3136-3149, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36260815

RESUMO

ConspectusPhotochromic diarylethenes featuring reversible regulation by external light irradiation have attracted increasing attention in versatile applications such as logic gates, supramolecular systems, liquid crystals, and super-resolution imaging because of their outstanding bistability and fatigue resistance. However, for typical diarylethene systems, there always exist three typical unsolved issues. The first is how to modulate the bistability between the open and closed forms from the viewpoint of ethene bridge aromaticity. The second is how to decrease and avoid the photoinactive parallel conformer in order to achieve a high quantum yield, since the open form possesses the photoactive antiparallel (ap) conformation and the photoinactive parallel (p) conformation. Because of the typical rapid rotation of the flexible side aryl groups, the two conformers cannot be separated efficiently, thereby resulting in a relatively low photocyclization quantum yield. The third is how to fulfill the enantiospecific transformation with reversibility to photomodulate the chirality. Stereochemically, the ap conformer with C2 symmetry can be further subdivided into a pair of enantiomers with P and M helicity originating from the central hexatriene moiety. Similarly, the rapid rotation can also lead to the loss of intrinsic chirality, restricting the development and application of light-driven chiroptical switches. Accordingly, it is desirable to construct a specific diarylethene system to break through these bottlenecks for real versatile applications.Our group has recently developed a unique sterically hindered diarylethene system based on benzobis(thiadiazole) as the ethene bridge for completely solving these issues. We introduce a low-aromaticity benzobis(thiadiazole) unit into the diarylethene as a central ethene bridge with incomparably high bistability. To block or freeze the rotation of flexible side aryls, we further incorporate a large bulky benzothiophene unit to induce a large steric hindrance, or rotation barrier, between the ethene bridge and side aryls, thereby successfully separating multiple conformers of the diarylethenes with high photocyclization quantum yields and enantiospecific photoreaction. Consequently, given such a fantastic building block, we enhance its performance by means of supramolecular self-assembly, thereby realizing unique conformer-dependent self-assembly as well as unprecedented concerted isomerization and enantiospecific photoreaction of photoresponsive metallacycles. In addition, decoration of the intrinsically chiral diarylethenes with mesogenic units can enable us to manipulate the helical superstructure of liquid crystals, thus achieving a multiple anticounterfeiting technique and a quadridimensional manipulable laser. We also unravel the dual aggregation-induced emission (AIE) behavior of the sterically hindered diarylethene, especially as applied in super-resolution imaging.

9.
Opt Express ; 31(2): 2846-2859, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785289

RESUMO

We previously designed a dual-axis piezoelectric MEMS mirror with a low crosstalk gimbal structure, which is utilized as the key device for further research for laser beam scanning. This paper mainly focuses on studying the Lissajous scanning resolution of this MEMS mirror with frequency ratio and phase modulation. For accurately evaluating the scanning resolution, the center angular resolution of Lissajous scanning is redefined by theoretical calculation and verified with experimental measurement. Meanwhile, the scanning nonlinearity of MEMS mirror is studied carefully. Finally, the MEMS mirror works at the state of pseudo-resonance, and the center angular resolution better than 0.16° (H) × 0.03° (V) is achieved at a scanning Field of view (FoV) of 35.0° (H) × 16.5° (V). Moreover, a feasible route of resolution adjustable Lissajous scanning is provided by optimization of frequency ratio and phase modulation, which is helpful for high definition and high frame rate (HDHF) laser scanning imaging with the dual-axis mirror.

10.
BMC Cardiovasc Disord ; 23(1): 93, 2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-36803662

RESUMO

BACKGROUND: Previous studies have examined the associations of health literacy and social support with medication adherence among patients with hypertension. However, limited evidence exists regarding the mechanisms underlying the relationship between these factors and medication adherence. PURPOSE: To explore the prevalence of medication adherence and its determinants in patients with hypertension in Shanghai. METHODS: A community-based cross-sectional study was conducted among 1697 participants with hypertension. We collected sociodemographic and clinical characteristics as well as data regarding health literacy, social support, and medication adherence using questionnaires. We examined interactions among the factors using a structural equation model. RESULTS: The participants included 654 (38.54%) patients with a low degree of medication adherence and 1043 (61.46%) patients with a medium/high degree of adherence. Social support directly influenced adherence (ß = 0.165, P < 0.001) and indirectly influenced adherence through health literacy (ß = 0.087, P < 0.001). Health literacy directly influenced adherence (ß = 0.291, P < 0.001). Education indirectly affected adherence through both social support (ß = 0.048, P < 0.001) and health literacy (ß = 0.080, P < 0.001). Moreover, there was a sequential mediating effect of social support and health literacy on the association between education and adherence (ß = 0.025, P < 0.001). After controlling for age and marital status, similar results were also obtained, indicating a good model fit. CONCLUSIONS: The degree of medication adherence among hypertensive patients needs to improve. Health literacy and social support had both direct and indirect effects on adherence, and thus, these factors should be considered as tools to improve adherence.


Assuntos
Letramento em Saúde , Hipertensão , Humanos , Estudos Transversais , China/epidemiologia , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Adesão à Medicação , Inquéritos e Questionários , Apoio Social
11.
J Mater Sci Mater Med ; 34(7): 33, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37466722

RESUMO

Natural medicines plants are significant considerable attention as potential therapeutic agents for bone tissue engineering. Cissus quadrangularis L (CQ). is a potent therapeutic plant known for its own osteogenic properties. In this research work, a phytoconstituents-filled composite was produced by incorporating CQ extract with gelatin (Gel) and pectin (Pec) polymers collective through ß- tricalcium phosphate (ß-TCP) bioceramic via a green template method. The effect of CQ-filled composite morphology and chemical structural properties, in vitro cytotoxicity, cell proliferation, and differentiation was investigated. FTIR spectroscopic results indicated the prepared materials' structural confirmation. The CQ extract was the alcoholic -OH merge with the hydroxyl and -NH groups in the range of 3000 cm-1 to 3500 cm-1. Scanning electron microscopy images showed that the ß-TCP ceramic was perfectly embedded in Gel-Pec polymeric matrix, which is important for bone regeneration. In vitro cell culture results indicated that ß-TCP/Gel-Pec/CQ composite provided 92.0% of a favorable substrate for mesenchymal stem cell viability. The gene expression and RT-PCR studies represent the materials with good osteogenic expression, especially the ß-TCP/Gel-Pec/CQ composite is observed at 168.0% and 188.0% for RUNx2 and OCN, respectively. The result of the physicochemical characterizations and cell viability studies suggest that CQ-loaded ß-TCP/Gel-Pec composite can serve as a potential biomaterial for bone tissue repair and regeneration.


Assuntos
Cissus , Cissus/química , Polímeros/farmacologia , Regeneração Óssea , Fosfatos de Cálcio/química , Osteogênese , Diferenciação Celular
12.
Angew Chem Int Ed Engl ; 62(52): e202316647, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37968887

RESUMO

The development of ultra-long room-temperature phosphorescence (UL-RTP) in processable amorphous organic materials is highly desirable for applications in flexible displays, anti-counterfeiting, and bio-imaging. However, achieving efficient UL-RTP from amorphous materials remains a challenging task, especially with activation by visible light and a bright afterglow. Here we report a general and rational molecular-design strategy to enable efficient visible-light-excited UL-RTP by multi-esterification of a rigid large-plane phosphorescence core. Notably, multi-esterification minimizes the aggregation-induced quenching and accomplishes a 'four birds with one stone' possibility in the generation and radiation process of UL-RTP: i) shifting the excitation from ultraviolet light to blue-light through enhancing the transition dipole moment of low-lying singlet-states, ii) facilitating the intersystem crossing process through the incorporation of lone-pair electrons, iii) boosting the decay process of long-lived triplet excitons resulting from a significantly increased transition dipole moment, and iv) reducing the intrinsic triplet nonradiative decay by substitution of high-frequency vibrating hydrogen atoms. All these factors synergistically contribute to the most efficient and stable visible-light-stimulated UL-RTP (lifetime up to 2.01 s and efficiency up to 35.4 % upon excitation at 450 nm) in flexible films using multi-esterified coronene, which allows high-tech applications in single-component time-delayed white light-emitting diodes and information technology based on flashlight-activated afterglow encryption.

13.
J Am Chem Soc ; 144(45): 20773-20784, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343183

RESUMO

Active engineering and modulation of optical spectra in a remote and fully reversible light is urgently desired in photonics, chemistry, and materials. However, the real-time regulation of multiple optical information such as wavelength, bandwidth, reflectance, and polarization is still a longstanding issue due to the lack of an appropriate photoresponsive candidate. Herein, we propose an additional "degree-of-freedom (DOF)" in a photo-modulated soft helix, and build up an unprecedented inhomogeneous helical pitch length with light-reconfiguring property, fatigue resistance, and reversibility. For the working model, the intrinsic chiral photoswitch LBC5 is employed as an actuator to modulate the helical pitch length, which is proportional to the irradiation intensity, and the unique broadband absorbance photo-modulator BTA-C5 is incorporated as an attenuator of the transmitted light to decrease its intensity along the sample thickness, therefore successfully adding another controlled DOF on the pitch length distribution (i.e., homogeneous or inhomogeneous) apart from the common soft helix with only a single DOF on the pitch length. The absorbance photo-modulator BTA-C5 with a unique variable broadband absorption enables the light to reconfigure the helical pitch from homogeneous to inhomogeneous, thereby achieving the robust fatigue-resistance establishment of reversible spectral programming. The established light-reconfigurable inhomogeneous helical pitch with the photoresponsive modulator BTA-C5 can provide a breakthrough to control absorbance and chirality, especially for dynamically broadening and narrowing the bandwidth on demand, and further enable the ever-desired broadband NIR circularly polarized luminescence (CPL) with a high dissymmetry factor glum of up to 1.88. The cutting-edge photoswitchable inhomogeneous soft helical pitch provides access to multi-freedom control in soft materials, optics, biophotonics, and other relevant fields.


Assuntos
Luminescência , Óptica e Fotônica
14.
Int Orthop ; 46(12): 2821-2828, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36069956

RESUMO

OBJECTIVE: To introduce the surgical technique and clinical outcomes of arthroscopic anterior talofibular ligament (ATFL) repair using the Internal Brace and lasso-loop technique for chronic ankle lateral instability. METHODS: A retrospective study was performed on 29 patients who underwent all-arthroscopic ATFL repair with the Internal Brace and lasso-loop technique from January to August 2020. The patients included 24 males and five females, with a mean age of 30.17 years. Through the accessory anterolateral (AAL) portal, we drilled the bone tunnels and fixed the tape with 4.75 mm and 3.5 mm "SwiveLock" anchors and reattached the torn ligament by the lasso-loop technique. RESULTS: All 29 patients underwent all-arthroscopic procedures smoothly without serious complications, such as infection and important nerve or vessel injuries. There were eight cases of lateral malleolar avulsion fractures and ten cases of talus cartilage injury. The visual analog scale (VAS), Karlsson-Peterson, Tegner, and American Orthopedic Foot and Ankle Society (AOFAS) scores were used to evaluate the clinical consequences. All the patients were followed up for 18.66 ± 4.85 months on average. The average pre-operative VAS score was 4.69 ± 1.04, which was significantly higher than the average post-operative VAS score of 1.14 ± 1.56. At the final follow-up appointments, the averages of Karlsson-Peterson, AOFAS, and Tenger scores were 75.83 ± 9.44, 88.31 ± 6.81, and 6.93 ± 1.79, respectively, which was significantly higher than that before the operation. CONCLUSION: This arthroscopic anterior talofibular ligament repair with the Internal Brace and lasso-loop technique achieves satisfactory clinical outcomes with the benefits of high safety and reliability for chronic ankle lateral instability.


Assuntos
Fraturas do Tornozelo , Instabilidade Articular , Ligamentos Laterais do Tornozelo , Humanos , Feminino , Masculino , Adulto , Estudos Retrospectivos , Tornozelo , Reprodutibilidade dos Testes , Ligamentos Laterais do Tornozelo/cirurgia , Instabilidade Articular/cirurgia , Artroscopia/efeitos adversos , Articulação do Tornozelo/cirurgia
15.
Molecules ; 27(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36432090

RESUMO

Photosensitizers equipped with high reactive oxygen species (ROS) generation capability and bright emission are essential for accurate tumor imaging and precise photodynamic therapy (PDT). However, traditional aggregation-caused quenching (ACQ) photosensitizers cannot simultaneously produce desirable ROS and bright fluorescence, resulting in poor image-guided therapy effect. Herein, we report an aggregation-induced emission (AIE) photosensitizer TCM-Ph with a strong donor-π-acceptor (D-π-A) structure, which greatly separates the HOMO-LUMO distribution and reduces the ΔEST, thereby increasing the number of triplet excitons and producing more ROS. The AIE photosensitizer TCM-Ph has bright near-infrared emission, as well as a higher ROS generation capacity than the commercial photosensitizers Bengal Rose (RB) and Chlorine e6 (Ce6), and can effectively eliminate cancer cells under image guidance. Therefore, the AIE photosensitizer TCM-Ph has great potential to replace the commercial photosensitizers.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio , Diagnóstico por Imagem , Piridinas
16.
Chemistry ; 27(16): 5240-5245, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33442888

RESUMO

In this study, photoswitchable fluorescent supramolecular metallacycles with high fatigue-resistance have been constructed by coordination-driven self-assembly by using bithienylethene with dipyridyl units (BTE) as a coordination donor and a fluorescent di-platinum(II) (Pt-F) as a coordination acceptor. The photo-triggered reversible transformation between the ring-open and ring-closed form of the metallacycles was confirmed by 1 H NMR, 31 P NMR, and UV/Vis spectroscopy. This unique property enabled a reversible noninvasive "off-on" switching of fluorescence through efficient Förster resonance energy transfer (FRET). Importantly, the metallacycles remained structurally intact after up to 10 photoswitching cycles. The photoresponsive property and exceptional photostability of the metallacycles posit their potential promising application in optical switching, image storage, and super-resolution microscopy.

17.
Environ Sci Technol ; 55(10): 6783-6790, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33945265

RESUMO

River delta-front estuaries (DEs) are vital interfaces for fluxes between terrestrial and marine environments. However, deep uncertainty exists in estimating the sedimentary pollutant flux from terrestrial environments in DEs due, in part, to a lack of direct measurements in these dynamic and complicated regions and uncertainty in the calculation method. Due to its high sediment content, the Yellow River (YR) has a strong ability to adsorb phosphorus; therefore, it reliably reflects estuarine sedimentary processes. Here, through the comprehensive analysis of field samples, monitoring data and remote sensing images, we conclude that riverine fine particles control the deltaic estuary pollution status and that particle size is the key factor. Based on the stable relationships between phosphorus and heavy metals, with r2 values of 0.990, 0.992, and 0.639 for As, Cd, and Cr, respectively, we estimated that the P flux reached 22.68 g/m2 yr in 2017. Analysis of the YR high-silt sediment load, which has a strong phosphorus adsorption ability and constitutes a substantial fraction of global fluvial sediment transport, revealed a negative correlation between the riverine sediment load and the estuarine phosphorus flux.


Assuntos
Rios , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Fósforo/análise , Poluentes Químicos da Água/análise
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(11): 1290-1297, 2021 Nov 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-34911865

RESUMO

Post-traumatic osteomyelitis is one of the most common disorders of bone infection, which is secondary to open fracture caused by machinery injury, traffic accident, and it is also the main manifestation in the postoperative infection of open fracture. After trauma, bacteria invade bone tissue and reproduce rapidly in large quantities, which easily leads to osteomyelitis. Patients are often complaint of pain at the affected limb, loss of function, or even amputation due to deteriorated infection, resulting in loss of labor capability and poor quality of life. Because the diagnosis and treatment are not timely and standard, the treatment for post-traumatic osteomyelitis is often delayed, resulting in the difficulty of clinical cure. It also makes patients and their families bear a serious financial burden. However, the diagnosis and treatment for this disease is difficult for orthopedic physicians. In recent years, imaging methods (such as CT and MRI) combined with immune techniques have significantly improved the diagnostic accuracy and early diagnosis ability. The application of new diagnostic technologies (such as gene chip and second-generation sequencing) also makes the diagnosis more convenient and sensitive. The novel reconstruction and repair surgery (such as Ilizarov technology and Orthofix LRS technology) provides new treatment direction for orthopedic surgeons and patients.


Assuntos
Técnica de Ilizarov , Osteomielite , Humanos , Osteomielite/diagnóstico , Osteomielite/terapia , Qualidade de Vida , Resultado do Tratamento
19.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(4): 426-431, 2021 Apr 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-33967091

RESUMO

Rotator cuff injuries are the most common cause of shoulder pain and dysfunction. Ideal animal shoulder models should have similar shoulder anatomy and function as human, and are able to replicate the microenvironment change after tendon injury. At present, a variety of animal models including rat, mouse, rabbit, sheep, canine, bovine, and primate have been used to study the mechanism of rotator cuff injury, effects of different repair techniques, and factors affecting tendon to bone healing. Although large animal models are more anatomically similar to humans, small animal models are more convenient in revealing the biological mechanism of rotator cuff injury and healing. Choosing appropriate animal models based on research objectives and establishing new small animal models play a critical role in revealing the mechanism of rotator cuff diseases and developing novel treating strategies.


Assuntos
Lesões do Manguito Rotador , Traumatismos dos Tendões , Animais , Bovinos , Modelos Animais de Doenças , Cães , Camundongos , Coelhos , Ratos , Manguito Rotador , Ovinos , Cicatrização
20.
Angew Chem Int Ed Engl ; 60(28): 15590-15597, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33890390

RESUMO

Directly converting sunlight into hydrogen fuels using particulate photocatalysts represents a sustainable route for clean energy supply. Organic semiconductors have emerged as attractive candidates but always suffer from optical and exciton recombination losses with large exciton "dead zone" inside the bulk material, severely limiting the catalytic performance. Herein, we demonstrate a facile strategy that combines a scalable flash nanoprecipitation (FNP) method with hydrophilic soluble polymers (PC-PEG5 and PS-PEG5) to prepare highly efficient nanosized photocatalysts without using surfactants. Significantly, a 70-fold enhancement of hydrogen evolution rate (HER) is achieved for nanosized PC-PEG5, and the FNP-processed PS-PEG5 shows a peak HER rate of up to 37.2 mmol h-1 g-1 under full-spectrum sunlight irradiation, which is among the highest results for polymer photocatalysts. A scaling-up production of nanocatalyst is demonstrated with the continuously operational FNP.

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