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Circularly polarized luminescence (CPL) materials have attracted considerable attention for their promising applications in encryption, chiral sensing, and three-dimensional (3D) displays. However, the preparation of high-efficiency, pure blue CPL materials remains challenging. In this study, we reported an enantiomeric pair of triangle copper(I) clusters (R/S-Cu3) rigidified by employing chiral N-heterocyclic carbene (NHC) ligands with two pyridine-functionalized wingtips. These chiral clusters emitted pure blue phosphorescence that overlapped with that of the commercial blue phosphor having Commission Internationale de l'Eclairage (CIE) chromaticity coordinates of (0.14, 0.10), and the films exhibited an unprecedented photoluminescence quantum yield (PLQY) of â¼70.0%. Additionally, the solutions showed very bright circularly polarized phosphorescence (CPP) with a dissymmetry factor of ±2.1 × 10-3. The excellent solubility and photostability endowed these pure-blue-emitting chiral clusters with promising applications as pure blue CPP inks for 3D printing white objects, such as precise-atomic-enlarged models of metal clusters and a lovely white stereoscopic "rabbit". The intricate mechanism underlying blue phosphorescence in this small cluster and across various states is elucidated through a comprehensive approach that integrates thorough analysis of luminescence properties, controlled experiments, and theoretical calculations. For the first time, we propose that the dominant high-energy emission center is constituted by delocalized hybrid orbitals over multiple atomic centers, encompassing both the metal and the coordinated atoms. This challenges stereotypical assumptions that the cluster center solely supports low-energy emissions. This work expands the currently limited range of CPP functional materials and provides a new direction for CPP applications involving NHC-stabilized metal clusters.
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Primary explosive, as a reliable initiator for secondary explosives, is the central component of micro-initiators for modern aerospace systems and military operations. However, they are typically prepared as powders, posing potential safety risks because of the inevitable particles scattering issues in the actual working environments. Here, the fabrication of a highly adaptive bulk material of copper azide (CA)-based safe primary explosive for micro-initiators is demonstrated. This bulk material, as derived by a complete azidation reaction of the carbonized metal-organic framework/cross-linked polymer hybrid template, enables the firm embedding of active CA species in a cross-linked carbon network (denoted as CA-C). Interestingly, this CA-C bulk material demonstrates multifarious mechanical stabilities (e.g., good shock and vibration resistance, and anti-overload capacity) in the simulated working conditions. Meanwhile, the CA contents in the CA-C bulk material reached as high as 70.3%, ensuring its detonation power. As a proof of concept, CA-C bulk material assembling in a micro-detonator can efficiently detonate the secondary explosive of CL-20 under laser irradiation. This work hereby advances the fabrication of safe and powerful primary explosives for the fulfillment of safe micro-initiator in a broad range of applications in aerospace systems.
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Covalent organic frameworks (COFs) are appealing photocatalysts for toxic chemical degradation. Great efforts have been devoted to regulate the photocatalytic performance of COFs by tuning their organic building blocks, but the relationship between COF linkage and photochemical properties has rarely been explored. Herein, we report the synthesis and characterisation of a novel aminal-linked porphyrinic COF, namely Por-Aminal-COF. Por-Aminal-COF (0.25â mol %) showed excellent photocatalytic activity toward the detoxification of the sulfur mustard simulant with a half-life (t1/2 ) of 5â min, which is far lower than that of traditional imine-linked Por-COF (t1/2 =16â min). Transient absorption spectroscopy indicated that the aminal linkages of Por-Aminal-COF facilitated the intersystem crossing process. Thus, Por-Aminal-COF showed higher triplet-state generation efficiency compared with Por-COF, consequently promoting the activation of oxygen molecular to singlet oxygen.
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A novel viologen-based multifunctional Eu-MOF was obtained by integrating a luminescent component Eu(NO3)3·6H2O and a viologen-functionalized ligand. The Eu-MOF not only exhibited reversible photochromic and electrochromic properties, but also displayed photoluminescent and electroluminochromic properties.
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Técnicas Eletroquímicas , Európio/química , Luminescência , Estruturas Metalorgânicas/química , Viologênios/química , Ligantes , Processos FotoquímicosRESUMO
OBJECTIVE: To explore the clinical efficacy of C3 expanded half lamina excision combined with unilateral open door laminoplasty for multiple segmental cervical spinal cord compression syndrome. METHODS: The clinical data of 58 patients with multiple segmental cervical spinal cord compression syndrome underwent surgical treatment between September 2014 and May 2018 were retrospectively analyzed. There were 34 males and 24 females with a mean age of 64.4 years old (ranged from 46 to 78 years old). Among them, 28 cases received the surgery of C3 expanded half lamina excision combined with C4-C7 unilateral open-door laminoplasty (improvedgroup), and 30 cases received a single C3-C7 unilateral open-door laminoplasty (traditional group). Operation time, intraoperative blood loss, complications including C5 nerve root palsy and axial symptoms were compared between two groups. To evaluate the situation of the imaging indicators by measuring the space available for the spinal cord through cross sectional MRI of cervical spine at the narrowest segment of C3 (including intervertebral disc levels of C3, 4). Pre- and post-operative Japanese Orthopedic Association(JOA) score, Neck Disability Index(NDI) score, and improvement rate of neurological function, were recorded and analyzed between the two groups. RESULTS: All the patients were followed up for 12 to 18 months with an average of(14.5±1.8) months for improved group and (14.5±1.9) months for traditional group, and no significant difference was found between the two groups (P>0.05). There was no significant difference in intraoperative blood loss and C5 nerve root palsy between the two groups (P>0.05). The operation time (119±10) min vs (126±12) min and axial symptoms 7.1%(2/28) vs 26.6%(8/30) was significant difference between the two groups (P<0.05). Preoperative and postoperative space available for the spinal cord of C3 was (93.61±9.02) mm3 and (153.50±12.76) mm3 respectively, which was obtained obvious improvement in all patients(P<0.05). At the final follow up, JOA scores of improved group and traditional group were 14.36±1.70 and 14.03±1.82 respectively, and NDI scores were 10.36±2.55 and 12.47±3.46 respectively, there was significant difference between two groups (P<0.05). However, there was no significant difference between two groups for the improvement rate (68.36±0.12)%VS (65.01±0.12)%of neurological function(P>0.05). CONCLUSION: C3 expanded half lamina excision combined with unilateral open-door laminoplasty is an effective method to treat multiple segmental cervical spinal cord compression syndrome, for it can not only fully relieved spinal cord compression, but also achievedgood effect in preventing complications such as axial symptoms by reducing stripping of muscles from C2 spinous process.
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Laminoplastia , Compressão da Medula Espinal , Idoso , Vértebras Cervicais/cirurgia , Estudos Transversais , Feminino , Humanos , Laminectomia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Co/Co9S8 nanoparticles encapsulated in a N, S, and O ternary-doped carbon matrix were synthesized utilizing a Co-NSOMOF as a single precursor, and they exhibited excellent bifunctional electrocatalytic activity for the OER and HER. Impressively, the water splitting cell exhibited a low cell voltage of 1.56 V at 10 mA cm-2. The high performances were attributed to the synergistic effect and the protection of multi-heteroatom doped carbon shells for active Co/Co9S8 nanoparticles.
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Metal-organic frameworks (MOFs) with light-harvesting building blocks provide an excellent platform to study energy transfer in networks with well-defined structures. Here, we report the synthesis, dissolution-recrystallization structural transformation (DRST) and the Förster resonance energy transfer (FRET) properties of a 2D microporous MOF {[Cd2(L1)3(Hdabco)2]·5DMAc·6H2O}n (Cd-MOF, 1). Complex 1 can be dissolved in water and three other products with different dimensions recrystallized from the aqueous solution under diverse reaction conditions were obtained. Due to the porosity and excellent blue luminescence properties of complex 1, we also studied the FRET process between 1 and guest dyes. Two distinct organic dye molecules viz., acridine orange (AO) and rhodamine B (RhB), are encapsulated in 1 which has honeycomb-type nanochannels, and their influence on fluorescence emission has also been studied. The microporous complex 1 in (AO + RhB)@1 serves as an energy funnel that harvests high energy excitation and channels it onto AO and then onto RhB. The steady-state fluorescence and fluorescence dynamics of emission reveal successfully the process of stepwise vectorial energy transfer. Therefore, MOFs could be a class of promising host materials to be further explored in the field of energy transfer between MOF-host and organic guests.
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Dioscin, a typical saponin, is widely present in the family of Dioscoreaceae, Liliaceae, Caryophyllaceae and Rosaceae, especially in Dioscoreaceae, including Discorea nipponica Makino, Dioscorea zingiberensis C. H. Wright and Dioscorea panthaica Prain et Burkill. Traditional Chinese medicine reported that dioscin plays a role in expectorant, relaxing the muscles and stimulating the blood circulation, aiding digestion and diuresis. With the development of science and technology in recent years, some new extraction and separation techniques and methods have been applied to the study of dioscin, and more and more pharmacological effects were found. Modern pharmacology studies have confirmed that dioscin had some activities on desensitization, anti-inflammatory, lipid-lowering, anti-tumor, hepatoprotection and anti-viral. After oral administration, dioscin is metabolized to diosgenin, which is the true active ingredient and is an important raw material to synthesize steroid hormone drugs. Therefore, the studies on dioscin are valueable and promising. In this review, we make a summary on the researches of dioscin including the extraction technology, separation and prepara- tion, chemical synthesis, drug metabolism, determination and pharmacological researches.
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Produtos Biológicos/farmacologia , Diosgenina/análogos & derivados , Extratos Vegetais/farmacologia , Animais , Produtos Biológicos/efeitos adversos , Produtos Biológicos/química , Diosgenina/efeitos adversos , Diosgenina/química , Diosgenina/farmacologia , Humanos , Extratos Vegetais/efeitos adversos , Extratos Vegetais/químicaRESUMO
OBJECTIVE: This study sought to use a meta-analysis approach to comprehensively evaluate correlations between the human leukocyte antigen-DR beta 1 (HLA-DRB1)*03 allele and chronic hepatitis B (CHB) in the Han Chinese population. METHODS: The China Biomedical Literature database (CBMdisc), the Chongqing VIP database (VIP), and the PubMed database were searched. Using the inclusion and exclusion criteria of this study, all relevant case-control studies retrieved in these searches that satisfied the conditions of this investigation were collected. Review Manager (RevMan) 5.2 software was used to conduct a meta-analysis on the results of these studies. RESULTS: There were 9 publications that satisfied the inclusion criteria. These publications included a total of 970 cases in the CHB group and 1185 cases in the normal control group. Egger's test revealed no significant publication bias. A comprehensive analysis indicated that the pooled odds ratio (OR) value was 1.94 with a 95% confidence interval (CI) of 1.23-3.06 (Z=2.84, p=0.004); these findings suggested that in the Han Chinese population, the HLA-DRB1*03 allele is a susceptibility allele related to the occurrence of CHB. CONCLUSION: There is a statistically significant correlation between the HLA-DRB1*03 allele and the occurrence of CHB in the Han Chinese population, and the HLA-DRB1*03 allele may be a susceptibility allele for this disease.
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Alelos , Frequência do Gene/genética , Cadeias HLA-DRB1/genética , Hepatite B Crônica/genética , Povo Asiático , China , Feminino , Humanos , MasculinoRESUMO
A flexible aromatic multicarboxylate ligand and Cd(II) ions assemble into a chiral multihelical porous metal-organic framework with second-order nonlinear optical and ferroelectric properties. The obtained guest-free form highly selectively senses small organic molecules and adsorbs large dye molecules.
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Alterations in energy metabolism play a major role in cancer development. Aconitase (ACO2) is an essential enzyme located in the mitochondria and catalyzes the interconversion of citrate and isocitrate in the tricarboxylic acid cycle. Recent studies suggest that the expression of ACO2 may be altered in certain types of cancer. The purpose of this study was to examine ACO2 expression in clinical tumor specimens from patients with gastric cancer and to evaluate the clinical relevance of ACO2 expression in gastric cancer. A total of 456 paraffin-embedded gastric cancer tissues and 30 pairs of freshly frozen tissues were used in this study. Real-time quantitative reverse transcription polymerase chain reaction, western blotting, and immunohistochemical staining were performed to measure ACO2 expression in tumor tissues and matched adjacent non-tumorous tissues. The results showed that the expression of ACO2 was significantly down-regulated in gastric cancer tissues compared with matched adjacent nontumorous tissues and was associated with clinical stage (p = 0.001), T classification (p = 0.027), N classification (p = 0.012), M classification (p = 0.002), and pathological differentiation states (p = 0.036). Patients with lower ACO2 expression had a shorter survival time than those with higher ACO2 expression. Univariate and multivariate analyses indicated that ACO2 expression functions as an independent prognostic factor (p < 0.001). Our data suggested that ACO2 could play an important role in gastric cancer and may potentially serve as a prognostic biomarker.
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Aconitato Hidratase/antagonistas & inibidores , Biomarcadores Tumorais/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Proteínas Mitocondriais/antagonistas & inibidores , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/enzimologia , Aconitato Hidratase/biossíntese , Aconitato Hidratase/genética , Idoso , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , Prognóstico , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Neoplasias Gástricas/genética , Taxa de Sobrevida/tendênciasRESUMO
OBJECTIVE: To explore the feasibility and clinical efficacy of unilateral pedicle screw fixation with transforaminal lumbar interbody fusion (TLIF) for the treatment of far lateral lumbar disc herniation. METHODS: From January 2007 to January 2011, 18 patients with far lateral lumbar disc herniation underwent a unilateral TLIF procedure in conjunction with posterior unilateral pedicle screw fixation. There were 13 males and 5 females,ranging in age from 42 to 73 years (means 58.5 years). All cases had single segment involved 5 cases in L3, 4, 10 cases in L4,5,3 cases in LSS. The visual analog scale (VAS) of low back pain and leg pain and Oswestry Disability Index scores were observed in postoperative and followed-up period, and compared with preoperative. RESULTS: The operation of 18 patients was successful,there were no severe complication. The average operative time was 105 min (85 to 125 min), the average amount of blood loss was 145 ml (90 to 340 ml). During the followed-up, the visual analog scale and Oswestry disability index scores were significant improved compared with preoperative (P < 0.05). All patients were followed up from 12 to 48 months with an average of 23 months, there was no implant break and displacement in postoperative X-ray. CONCLUSION: The surgical procedure of unilateral pedicle screw fixation with transforaminal lumbar interbody fusion had the advantage including less invasion, quickly recovery, short operative time, and saving fixation cost, it may provide an alternative treatment for patients with far lateral lumbar disc herniation.
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Parafusos Ósseos , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To explore the clinical application and therapeutic effect of open vertebroplasty for thoracolumbar metastatic tumor. METHODS: From September 2003 to December 2009, 21 patients with thoracolumbar metastatic tumor underwent the surgical procedure of posterior spinal cord decompression and open vertebroplasty combined with short-segmental pedicle screw fixation during the same intervention. There were 14 males and 7 females, ranging in age from 48 to 73 years with the mean of 59.5 years and ranging in course of disease from 1 to 4 months with an average of 2.5 months. The primary focus of the tumor of 19 cases were established, lung carcinoma was in 8 cases, breast cancer in 4 cases, prostate carcinoma in 4 cases, hepatocarcinoma in 2 cases and thyroid carcinoma in 1 case. The primary focus of 2 cases could not be established. The spinal function according to Frankel grade, grade B was in 4 cases, C in 6, D in 5, E in 6. The lumbar-back pain, height of anterior and posterior vertebral body, Cobb angle and spinal function were recorded before and after operation. RESULTS: The operation of all patients was successful, there were no severe complications and aggravation of spinal function. The VAS score of lumbar-back pain decreased from 8.78 +/- 0.45 preoperatively to 2.25 +/- 0.36 postoperatively. Among 16 cases combined with pathological fracture, the height of anterior spinal vertebral body increased from (12.7 +/- 2.1) mm preoperatively to (19.5 +/- 3.9) mm postoperatively; the height of posterior spinal vertebral body increased from (14.1 +/- 1.8) mm preoperatively to (20.3 +/- 2.3) mm postoperatively; Cobb angle decreased from (26.0 +/- 8.9) degrees preoperatively to (6.0 +/- 0.9) degrees postoperatively. There was significant difference above items between before and after operation (P < 0.05). The spinal function according to Frankel grade at final follow up, grade C was in 2 cases, D in 4, E in 15. All patients were followed up from 5 to 28 months with an average of 14 months, there was no loosening and breakage of internal fixity, 15 cases died during follow-up period. CONCLUSION: The surgical intervention can effectively preserve spinal instability and alleviate the spinal cord symptoms, improve the life quality of patients. It may provide an alternative treatment for patients in poor general health and shorter life expectancy.