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Luminescent metal halides have been exploited as a new class of X-ray scintillators for security checks, nondestructive inspection, and medical imaging. However, the charge traps and hydrolysis vulnerability are always detrimental to the three-dimensional ionic structural scintillators. Here, the two zero-dimensional organic-manganese(II) halide coordination complexes 1-Cl and 2-Br were synthesized for improvements in X-ray scintillation. The introduction of a polarized phosphine oxide can help to increase the stabilities, especially the self-absorption-free merits of these Mn-based hybrids. The X-ray dosage rate detection limits reached up to 3.90 and 0.81 µGyair/s for 1-Cl and 2-Br, respectively, superior to the medical diagnostic standard of 5.50 µGyair/s. The fabricated scintillation films were applied to radioactive imaging with high spatial resolutions of 8.0 and 10.0 lp/mm, respectively, holding promise for use in diagnostic X-ray medical imaging.
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The study of facile-synthesis and low-cost X-ray scintillators with high light yield, low detection limit and high X-ray imaging resolution plays a vital role in medical and industrial imaging fields. However, the optimal balance between X-ray absorption, decay lifetime and excitonic utilization efficiency of scintillators to achieve high-resolution imaging is extremely difficult due to the inherent contradiction. Here two thermally activated delayed fluorescence (TADF)-actived coinage-metal clusters M6 S6 L6 (M=Ag or Cu) were synthesized by simple solvothermal reaction, where the cooperation of heavy atom-rich character and TADF mechanism supports strong X-ray absorption and rapid luminescent collection of excitons. Excitingly, Ag6 S6 L6 (SC-Ag) displays a high photoluminescence quantum yield of 91.6 % and scintillating light yield of 17420â photons MeV-1 , as well as a low detection limit of 208.65â nGy s-1 that is 26â times lower than the medical standard (5.5â µGy s-1 ). More importantly, a high X-ray imaging resolution of 16â lp/mm based on SC-Ag screen is demonstrated. Besides, rigid core skeleton reinforced by metallophilicity endows clusters M6 S6 L6 strong resistance to humidity and radiation. This work provides a new view for the design of efficient scintillators and opens the research door for silver clusters in scintillation application.
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Anisotropic charge transport plays a pivotal role in clarifying the conductivity mechanism in direct X-ray detection to improve the detection sensitivity. However, the anisotropic photoelectric effect of semiconductive single crystal responsive to X-ray is still lacking of theoretical and experimental proof. The semiconductive coordination polymers (CPs) with designable structures, adjustable functions, and high crystallinity provide a suitable platform for exploring the anisotropic conductive mechanism. Here,the study first reveals a 1D conductive transmission path for direct X-ray detection from the perspective of structural chemistry. The semiconductive copper(II)-based CP 1 single crystal detector exhibits unique anisotropic X-ray detection performance. Along the 1D π-π stacking direction, the single crystal device (1-SC-a) shows a superior sensitivity of 2697.15 µCGyair -1 cm-2 and a low detection limit of 1.02 µGyair s-1 among CPs-based X-ray detectors. This study provides beneficial guidance and deep insight for designing high-performance CP-based X-ray detectors.
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A charge density wave (CDW) is a collective quantum phenomenon in metals and features a wavelike modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by a commensurate 2 × 2 CDW order. Furthermore, we observed a CDW energy gap of up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX2 films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of a Zr 4d derived elliptical electron conduction band at the corners of the Brillouin zone.
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Two examples of efficient cathode-ray scintillation coordination polymers with good stability at high voltage were prepared by conjugating luminescent groups with d10 metal ions. The synergistic effect of inorganic metal and organic ligand suppresses the self-quenching of the conjugated luminescent groups and enhances the scintillation performance. This work provides new ideas for the design of new field-emission displays and cathode-ray scintillation materials.
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Background: Ischemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat. Methods: Rat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed. Results: Pre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators. Conclusion: Our result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.
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Recent experiments have tuned the monolayer 1T^{'}-WTe_{2} to be superconducting by electrostatic gating. Here, we theoretically study the phonon-mediated superconductivity in monolayer 1T^{'}-WTe_{2} via charge doping. We reveal that the emergence of soft-mode phonons with specific momentum is crucial to give rise to the superconductivity in the electron-doping regime, whereas no such soft-mode phonons and no superconductivity emerge in the hole-doping regime. We also find a superconducting dome, which can be attributed to the change of Fermi surface nesting conditions with electron doping. By taking into account the experimentally established strong anisotropy of temperature-dependent upper critical field H_{c2} between the in-plane and out-of-plane directions, we show that the superconducting state probably has the unconventional equal-spin-triplet pairing in the A_{u} channel of the C_{2h} point group. Our studies provide a promising understanding to the doping dependent superconductivity and strong anisotropy of H_{c2} in monolayer 1T^{'}-WTe_{2}, and can be extended to understand the superconductivity in other gated transition metal dichalcogenides.
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CONTEXT: Anti-inflammatory drugs are often used to treat chronic knee pain (CKP), but their long-term use is associated with decreased effectiveness and numerous side effects. Complementary and alternative medicine provides additional treatments for the condition, including percutaneous electrical nerve stimulation (PENS). However, the benefits of PENS for treatment of CKP are still controversial. OBJECTIVE: The study intended to assess the effects and safety of PENS for treatment of CKP. METHODS: This study was a 2-arm, randomized, sham-controlled trial. SETTING: The study took place at the Fourth People's Hospital of Shaanxi (Xi'an, China). PARTICIPANTS: Participants were 72 patients at the hospital being treated for CKP. INTERVENTION: Participants were randomly divided into a real PENS group and a sham PENS group at a ratio of 1:1. All patients received etoricoxib and either real or sham PENS therapy, 3 ×/wk for 8 wk, at the same local acupoints around the knee. OUTCOME MEASURES: The primary outcome, pain, was measured on a numeric rating scale (NRS). Secondary outcomes, stiffness and physical function, were evaluated using the Western Ontario and McMaster Universities arthritis index (WOMAC) and the short-form 36-item health survey (SF-36) to obtain a score on the physical component scale (PCS) and the mental component scale (MCS). The NRS and the WOMAC were administered at initiation of treatment to establish a baseline and again after 8 wk of treatment. The SF-36 was administered postintervention. RESULTS: At the end of 8 wk, the group receiving the real PENS exhibited statistically significant improvements in both primary and secondary outcomes compared with the group receiving the sham PENS treatment. CONCLUSIONS: The findings suggest that treatment with the real PENS with etoricoxib is effective for treatment of CKP.
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Osteoartrite do Joelho/terapia , Estimulação Elétrica Nervosa Transcutânea , Humanos , Dor , Medição da Dor , Resultado do TratamentoRESUMO
While pyrite-type PtBi_{2} with a face-centered cubic structure has been predicted to be a three-dimensional (3D) Dirac semimetal, experimental study of its physical properties remains absent. Here we report the angular-dependent magnetoresistance measurements of a PtBi_{2} single crystal under high magnetic fields. We observed extremely large unsaturated magnetoresistance (XMR) up to (11.2×10^{6})% at T=1.8 K in a magnetic field of 33 T, which is comparable to the previously reported Dirac materials, such as WTe_{2}, LaSb, and NbP. The crystals exhibit an ultrahigh mobility and significant Shubnikov-de Hass quantum oscillations with a nontrivial Berry phase. The analysis of Hall resistivity indicates that the XMR can be ascribed to the nearly compensated electron and hole. Our experimental results associated with the ab initio calculations suggest that pyrite PtBi_{2} is a topological semimetal candidate that might provide a platform for exploring topological materials with XMR in noble metal alloys.
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A flexible metal-organic framework (FMOF) with functionalized pores was hydrothermally synthesized to improve CO2 affinity and selectivity. The obtained FMOF exhibits a reversible shrinking and swelling framework transformation, which is triggered by the adsorption of CO2 rather than by the adsorption of N2 and CH4. At ambient temperature and an atmospheric pressure, this FMOF shows not only a high CO2 uptake (98 cm(3) g(-1), 19.3 wt %) but also a good calculated adsorption selectivity for CO2 over both CH4 and N2 (CO2/CH4 50:50 v/v: 28.6:1, CO2/N2 15:85 v/v: 210.4:1 calculated by ideal adsorbed solution theory), indicating potential applications in the purification of natural gas and industrial flue gas.
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AIM: To investigate the effect of low-dosage steroid therapy in patients with severe aristolochic acid nephropathy (AAN). METHODS: Forty-three chronic AAN patients in the Peking Union Medical College Hospital and the First Affiliated Hospital of Xinxiang Medical College were included in this study from November 1998 to October 2013. According to the treatment method, the patients were divided into a steroid group (SG, n = 25) and a control group (CG, n = 18). The serum biochemical indicators at the basement in the two groups exhibited no obvious statistical differences. In comparison with the baseline data, the levels of serum creatinine at 3, 6, 9, and 12 months were analyzed. The blood pressure, haemoglobin, serum biochemical indicators, and the side-effects of steroid application were also observed. Urinary macrophage chemoattractant protein-1 (MCP-1) and transforming growth factor-1 (TGF-1) amounts were measured as well. RESULTS: (i) The serum creatinine content in the CG group was significantly higher than the baseline level during the follow-up(6, 9, and 12 months later), whereas in the SG group it decreased during the 3-6 month period and remained stable within 1 year. (ii) The biochemical indicators, blood pressure, and haemoglobin persisted stable. (iii) The side-effects of low-dosage steroid therapy were not severe and were tolerated by the AAN patients. (4) Urinary MCP-1 and TGF-1 concentrations were positively correlated with serum creatinine and decreased in the SG group. CONCLUSION: Low-dosage steroid therapy reversed or delayed the renal failure progression in severe chronic AAN patients, which may be associated with the suppression of MCP-1 and TGF-ß1 activities.
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Ácidos Aristolóquicos/efeitos adversos , Glucocorticoides , Falência Renal Crônica , Idoso , Fatores Quimiotáticos/sangue , China , Creatinina/sangue , Progressão da Doença , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos/métodos , Feminino , Seguimentos , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/induzido quimicamente , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/tratamento farmacológico , Testes de Função Renal/métodos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estatística como Assunto , Fator de Crescimento Transformador beta1/sangue , Resultado do TratamentoRESUMO
This study investigated the effects of amygdalin (AMY, a cyanogenic glycoside widely distributed in the fruits and seeds of Rosaceae plants) on cardiac performance and ventricular remodeling in a rat model of myocardial infarction (MI). We also investigated whether the combination of AMY with exercise training (ExT) has a beneficial synergistic effect in treating MI rats. MI was induced by the ligation of the left anterior descending coronary artery in male SD rats. ExT or AMY treatment was started 1 week after MI and continued for 1 week (short-term) or 8 weeks (long-term). Cardiac function was evaluated by echocardiographic and hemodynamic parameters. Heart tissues were harvested and subjected to 2,3,5-triphenyl-tetrazolium chloride, Masson's trichrome, hematoxylin-eosin, and immunohistochemical staining. Gene expression was determined by quantitative polymerase chain reaction. Western blot gave a qualitative assessment of protein levels. AMY or ExT improved cardiac function and reduced infarct size in MI rats. AMY or ExT also suppressed myocardial fibrosis and attenuated inflammation in the infarct border zone of hearts from MI rats, as evidenced by inhibition of collagen deposition, inflammatory cell infiltration, and pro-inflammatory markers (interleukin 1ß, interleukin 6, tumor necrosis factor-α, and cyclooxygenase 2). Notably, the effects of AMY combined with ExT were superior to those of AMY alone or ExT alone. Mechanistically, these beneficial functions were correlated with the inhibition of MI-induced activation of the transforming growth factor-ß/Smad pathway. Collectively, AMY and ExT exert a synergistic effect on improving cardiac performance and ameliorating cardiac inflammation and fibrosis after MI, and the effects of long-term intervention were better than short-term intervention.
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Amigdalina , Infarto do Miocárdio , Animais , Ratos , Ratos Sprague-Dawley , Amigdalina/farmacologia , Infarto do Miocárdio/terapia , Inflamação/terapia , FibroseRESUMO
HLA-DPB1*1550:01 differs from HLA-DPB1*02:02:01:01 by one nucleotide in exon 2.
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Cadeias beta de HLA-DP , Nucleotídeos , Humanos , Alelos , Sequência de Bases , ChinaRESUMO
BACKGROUND & AIMS: Dysregulation of Wnt signaling has been involved in gastric tumorigenesis by mechanisms that are not fully understood. The receptor for activated protein kinase C (RACK1, GNB2L1) is involved in development of different tumor types, but its expression and function have not been investigated in gastric tumors. METHODS: We analyzed expression of RACK1 in gastric tumor samples and their matched normal tissues from 116 patients using immunohistochemistry. Effects of knockdown with small interfering RNAs or overexpression of RACK1 in gastric cancer cell lines were evaluated in cell growth and tumor xenograft. RACK1 signaling pathways were investigated in cells and zebrafish embryos using immunoblot, immunoprecipitation, microinjection, and in situ hybridization assays. RESULTS: Expression of RACK1 was reduced in gastric tumor samples and correlated with depth of tumor infiltration and poor differentiation. Knockdown of RACK1 in gastric cancer cells accelerated their anchorage-independent proliferation in soft agar, whereas overexpression of RACK1 reduced their tumorigenicity in nude mice. RACK1 formed a complex with glycogen synthase kinase Gsk3ß and Axin to promote the interaction between Gsk3ß and ß-catenin and thereby stabilized the ß-catenin destruction complex. On stimulation of Wnt3a, RACK1 repressed Wnt signaling by inhibiting recruitment of Axin by Dishevelled 2 (Dvl2). Moreover, there was an inverse correlation between expression of RACK1 and localization of ß-catenin to the cytoplasm/nucleus in human gastric tumor samples. CONCLUSIONS: RACK1 negatively regulates Wnt signaling pathway by stabilizing the ß-catenin destruction complex and act as a tumor suppressor in gastric cancer cells.
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Complexo de Sinalização da Axina/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superfície Celular/metabolismo , Neoplasias Gástricas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Via de Sinalização Wnt , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Complexo de Sinalização da Axina/genética , Estudos de Casos e Controles , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Desgrenhadas , Feminino , Proteínas de Ligação ao GTP/genética , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HEK293 , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Fosfoproteínas/metabolismo , Interferência de RNA , Receptores de Quinase C Ativada , Receptores de Superfície Celular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Neoplasias Gástricas/prevenção & controle , Fatores de Tempo , Transfecção , Proteínas Supressoras de Tumor/genética , Via de Sinalização Wnt/genética , Proteína Wnt3A/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , beta Catenina/metabolismoRESUMO
We employed two pairs of new in-situ-generated chiral amino acid-tetrazole ligands in constructing homochiral Zn(II) coordination compounds: [Zn(tzet)]n (1a for (S)-tzet and 1b for (R)-tzet, H2tzet = N-[2-(1H-tetrazol-5-yl)ethyl]tryptophan) and [Zn(tzep)(H2O)2]·H2O (2a for (S)-tzep and 2b for (R)-tzep, H2tzep = N-[2-(1H-tetrazol-5-yl)ethyl]proline), which were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Structural analysis reveals that 1 features a 2D homochiral framework generated by both tetrazolate and carboxylate bridges in tzet(2-) ligands. The isolated structure of 2 is stabilized by extensive hydrogen bonds, which leads to formation of a supramolecular 2D architecture. The absolute configuration induced at the nitrogen atoms of 1 and 2 is strictly related to the neighboring chiral carbon atoms by hydrogen-bond interactions. To further investigate their chirality, the combined experimental and theoretical analyses of circular dichroism spectra reveal the absolute configurations and nature of the Cotton effects. Solid-state excitation and emission spectra for 1 and 2 at room temperature were investigated with relevant density of states calculation, and tunable photoluminescence emission of 1 under different excitation wavelengths was discussed. As nitrogen-rich tetrazolate compounds, 1 and 2 possess higher enthalpies of combustion and may serve as a new family of promising energetic materials.
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The Al doping gallate phosphor (Ga(1-x)Al(x))2O3 : Cr3+ (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) was synthesized by a high temperature solid-state reaction method. The X-ray diffractions show that the phase of the phosphors remains to be Ga2 O3 structure with increase in the contents of Al3+ ion. Beside, the fact that the X-ray diffraction peak shifts towards big angles with increasing Al3+ ions content shows that Al3+ ions entered the Ga2 O3 lattice. The peaks of the excitation spectra located at 258, 300, 410 and 550 nm are attributed to the band to band transition of the matrix, charge transfer band transition, and 4A2 --> 4T1 and 4A2 --> 4T2 transition of Cr3+ ions, respectively. Those excitation spectrum peak positions show different degrees of blue shift with the increase in the Al3+ ions content. The blue shift of the first two peaks are due to the band gap energy of substrate and the electronegativity between Cr3+ ions and ligands increasing, respectively. The blue shift of the energy level transition of Cr3+ ion is attributed to crystal field strength increasing. The Cr3+ ion luminescence changes from a broadband emission to a narrow-band emission with Al3+ doping, because the emission of Cr3+ ion changed from 4 T2 --> 4A2 to 2E --> 4A2 transition with the crystal field change after Al3+ ions doping. The Al3+ ions doping improved the long afterglow luminescence properties of samples, and the sample showed a longer visible near infrared when Al3+ ions content reaches 0.5. The thermoluminescence curve shows the sample with suitable trap energy level, and this is also the cause of the long afterglow luminescence materials.
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Objective. Emotion recognition on the basis of electroencephalography (EEG) signals has received a significant amount of attention in the areas of cognitive science and human-computer interaction (HCI). However, most existing studies either focus on one-dimensional EEG data, ignoring the relationship between channels, or only extract time-frequency features while not involving spatial features.Approach. We develop spatial-temporal features-based EEG emotion recognition using a graph convolution network (GCN) and long short-term memory (LSTM), named ERGL. First, the one-dimensional EEG vector is converted into a two-dimensional mesh matrix, so that the matrix configuration corresponds to the distribution of brain regions at EEG electrode locations, thus to represent the spatial correlation between multiple adjacent channels in a better way. Second, the GCN and LSTM are employed together to extract spatial-temporal features; the GCN is used to extract spatial features, while LSTM units are applied to extract temporal features. Finally, a softmax layer is applied to emotion classification.Main results. Extensive experiments are conducted on the A Dataset for Emotion Analysis using Physiological Signals (DEAP) and the SJTU Emotion EEG Dataset (SEED). The classification results of accuracy, precision, and F-score for valence and arousal dimensions on DEAP achieved 90.67% and 90.33%, 92.38% and 91.72%, and 91.34% and 90.86%, respectively. The accuracy, precision, and F-score of positive, neutral, and negative classifications reached 94.92%, 95.34%, and 94.17%, respectively, on the SEED dataset.Significance. The above results demonstrate that the proposed ERGL method is encouraging in comparison to state-of-the-art recognition research.
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Nível de Alerta , Memória de Curto Prazo , Humanos , Eletroencefalografia , EmoçõesRESUMO
The design and synthesis of energetic materials (EMs) with high energy and reliable stabilities has attracted much attention in the field of EMs. In this work, we employed a strategy of the coordination polymerization of mild dicyanamide ions (DCA-), two isomeric ligands 1-methyl-5-aminotetrazole (1-MAT) and 2-methyl-5-aminotetrazole (2-MAT) to construct energetic coordination polymers (ECPs). Four new ECPs {[Co(DCA)2(1-MAT)2]·H2O}n1, [Cu(DCA)2(1-MAT)]n2, [Cd(DCA)2(1-MAT)2]n3 and [Cd(DCA)2(2-MAT)2]n4 were successfully synthesized through solvent evaporation routes. Compounds 1 and 4 display 1D chains, while 2 and 3 exhibit 2D-layered structures. Compounds 1-3 with the 1-MAT ligand all exhibit reliable thermal stabilities (> 200 °C). The calculated heats of detonation (ΔHdet) of 1-3 are all higher than 1.4 kJ g-1, which are higher than traditional explosive TNT (1.22 kJ g-1) and the reported ECP AgMtta (HMtta = 5-methyl-1H-tetrazole, ΔHdet = 1.32 kJ g-1). Furthermore, sensitivity testing demonstrates that 1-4 features low mechanical sensitivity to external mechanical action in contrast with the extremely sensitive azide-based ECPs [Cu3(2-MAT)2(N3)6]n. In addition, compound 2 shows hypergolic properties via an 'oxidizer-fuel' drop experiment, demonstrating its application prospects in the field of propellants. This work details an approach of synthesizing multipurpose ECPs with reliable stabilities by introducing mild dicyanamide anions into nitrogen-rich skeletons.
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Energetic materials (EMs) have been widely employed in both military and civilian areas for nearly two centuries. The introduction of high-energy azide anions to assemble energetic metal-organic frameworks (EMOFs) is an efficient strategy to enhance energetic properties. However, azido-based EMOFs always suffer low stabilities to external mechanical stimulation. Herein, we employed an in situ hydrothermal reaction as a technique to refine azide anions with a neutral triazole-cyano-based ligand TrzAt (TrzAt = 2-(1H-1,2,4-triazol-1-yl)acetonitrile) to yield two tetrazole-based EMOFs, namely, [ZnBr(trmetz)]n1 and [Cd(trmetz)2]n2 (Htrmetz = 5-(1,2,4-triazol-1-ylmethyl)-1H-tetrazole). Compound 1 features a closely packed 2D layered network, while compound 2 exhibits a 3D architecture. With azide anions inlaid into a nitrogen-rich and chelating ligand in the EMOFs, compounds 1 and 2 present remarkable decomposition temperatures (Tdec ≥ 300 °C), low impact sensitivities (IS ≥ 32 J) and low friction sensitivities (FS ≥ 324 N). The calculated heat of detonation (ΔHdet) values of 1 and 2 are 3.496 and 4.112 kJ g-1, respectively. In particular, the ΔHdet value of 2 is higher than that of traditional secondary explosives such as 2,4,6-trinitrotoluene (TNT, ΔHdet = 3.720 kJ g-1). These results indicate that EMOFs 1 and 2 may serve as potential replacements for traditional secondary explosives. This work provides a simple and effective strategy to obtain two EMOFs with satisfactory energy densities and reliable stabilities through an in situ hydrothermal technique for desensitization of azide anions.
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The study aims to lessen the monetary burden on patients and society by decreasing the price of proprietary drugs used in leukemia therapy. Flow cytometry, reverse transcription polymerase chain reaction, western blot, and a patient-derived xenograft mouse model were used to confirm the therapeutic effect of Pinellia ternata extract on leukemia. Three types of leukemia cells (K562, HL-60, and C8166 cell lines) were found to undergo early apoptosis (P ≤ .05) after being exposed to P. ternata extract, as measured by flow cytometry. Reverse transcription polymerase chain reaction results showed that P. ternata extract at both middle (300 µg/mL) and high (500 µg/mL) concentrations was able to down-regulate Bcl-2 and upregulate mRNA expression of Bax and caspase-3. In the patient-derived xenograft mouse model formed by BALB/c-nu/nu nude mice, immunohistochemistry indicated that P. ternata extract effectively suppressed the proliferation of leukemia cells. Therefore, P. ternata extract at 300 µg/mL and 500 µg/mL could effectively inhibit myeloid and lymphocytic leukemia cell proliferation and promote leukemia cell apoptosis by regulating Bax/Bcl-2 and caspase-3.