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The photoconversion of CO2 into valuable chemical products using solar energy is a promising strategy to address both energy and environmental challenges. However, the strongly adsorbed CO2 frequently impedes the seamless advancement of the subsequent reaction by significantly increasing the reaction activation energy. Here, we present a BiFeO3 material with lattice strain that collaboratively regulates the d/p-2π* orbitals hybridization between metal sites and *CO2 as well as *COOH intermediates to achieve rapid conversion of solidly adsorbed CO2 to critical *COOH intermediates, accelerating the overall CO2 reduction kinetics. Quasi in situ X-ray photoelectron spectroscopy and in situ Fourier Transform infrared spectroscopy combined with theoretical calculation reveals that the optimized Fe sites enhance the adsorption and activation effect of CO2, and continuous internal electrons are rapidly transferred to the reaction sites and injected into the surface *CO2 and *COOH under the condition of illumination, which promotes the rapid formation and stability of *COOH. Certainly, the performance of CO2 photoreduction to CO is improved by 12.81-fold compared with the base material. This work offers a new perspective for the rapid photoreduction process of strongly adsorbed CO2.
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Photocatalytic oxygen reductive H2O2 production is a promising approach to alternative industrial anthraquinone processes while suffering from the requirement of pure O2 feedstock for practical application. Herein, we report a spaced double hydrogen bond (IC-H-bond) through multi-component Radziszewski reaction in an imidazole poly-ionic-liquid composite (SI-PIL-TiO2) and levofloxacin hydrochloride (LEV) electron donor for highly efficient and selective photocatalytic air reductive H2O2 production. It is found that the IC-H-bond formed by spaced imino (-NH-) group of SI-PIL-TiO2 and carbonyl (-C=O) group of LEV can switch the imidazole active sites characteristic from a covered state to a fully exposed one to shield the strong adsorption of electron donor and N2 in the air, and propel an intenser positive potential and more efficient orbitals binding patterns of SI-PIL-TiO2 surface to establish competitive active sites for selectivity O2 chemisorption. Moreover, the high electron enrichment of imidazole as an active site for the 2e- oxygen reduction ensures the rapid reduction of O2. Therefore, the IC-H-bond enables a total O2 utilization and conversion efficiency of 94.8 % from direct photocatalytic air reduction, achieving a H2O2 production rate of 1518â µmol/g/h that is 16 and 23â times compared to poly-ionic-liquid composite without spaced imino groups (PIL-TiO2) and TiO2, respectively.
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Microtubule as an important target in the cancer therapy was used to design novel tubulin polymerization inhibitors. Sulfanilamide-1,2,3-triazole hybrids were designed by a molecular hybridization strategy and their antiproliferative activity against three selected cancer cell lines (BGC-823, MGC-803 and SGC-7901) were evaluated. All sulfanilamide-1,2,3-triazole hybrids displayed potent inhibitory activity against all cell lines. In particular, compound 10b showed the most excellent inhibitory effect against MGC-803 cells, with an IC50 value of 0.4 µM. Cellular mechanism studies elucidated that 10b induced apoptosis by decreasing the expression level of Bcl-2 and Parp and increasing the expression level of BAX. 10b inhibited the epithelial-mesenchymal transition process by up-regulating E-cadherin and down-regulating N-cadherin. Furthermore, the tubulin polymerization inhibitory activity in vitro of 10b was 2.4 µM. In vivo anticancer assay, 10b effectively inhibited MGC-803 xenograft tumor growth without causing significant loss of body weight. These sulfanilamide-1,2,3-triazole hybrids as potent tubulin polymerization inhibitors might be used as promising candidates for cancer therapy.
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Desenho de Fármacos , Polimerização , Sulfanilamida/síntese química , Sulfanilamida/farmacologia , Moduladores de Tubulina/síntese química , Moduladores de Tubulina/farmacologia , Tubulina (Proteína)/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Forma Celular/efeitos dos fármacos , Células Clonais , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Relação Estrutura-Atividade , Sulfanilamida/química , Moduladores de Tubulina/química , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Here, a novel transformed CdO with low coordination and N doping environment was simply synthesized through the involvement of the target molecule tetracycline (TC). The results showed that the shedding of surface hydroxyl groups led to a low coordination environment, and N doping formed a new doping energy level, which increased the charge density and promoted the migration and separation of photo-generated carriers. Its photocatalytic performance was 4.32 times higher than that of hydroxy-rich CdO and the selectivity coefficient was 4.8. Combined with theoretical calculation and in situ Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) analysis, the significant improvement of selectivity was due to the interaction of the doped N atom with the methyl carbon in TC. This work provided a new idea for the simultaneous construction of low coordination environment and N-doped materials for efficient selective photocatalysis.
Assuntos
Antibacterianos , Tetraciclina , Carbono , CatáliseRESUMO
AIMS: Traumatic brain injury (TBI) not only induces physiological disabilities but also leads to cognitive impairment. However, no effective therapeutic approach for TBI-related memory decline exists. In this study, we treated TBI mice with cinnamic acid (CNA) to detect whether CNA is able to rescue the memory deficits induced by TBI and to explore the potential mechanisms. MAIN METHODS: Mice were divided into the following groups: the sham group, the TBI group, the TBIâ¯+â¯CNA group and the CNA group. Basic physiological parameters, neurological severity score and brain water content were analyzed. The Morris water maze and inhibitory avoidance step-down task were used to determine learning and memory. Golgi staining was used to measure alterations in dendritic spines. Western blot analysis and a commercial kit were used to detect the content and activity of HDAC2. qPCR was used to detect the relative level of miR-455. KEY FINDINGS: CNA did not affect physiological function but effectively restored neurological function and brain edema. CNA alleviated the memory impairments induced by TBI in both the Morris water maze and step-down task. CNA also recovered abnormalities in the synapses of TBI mice by suppressing the activity of HDAC2. Furthermore, CNA did not alter HDAC mRNA because it promoted the expression of miR-455-3p, a miRNA that regulates HDAC2 at the posttranscriptional level. SIGNIFICANCE: The application of CNA effectively treats TBI-induced memory deficits by increasing miR-455-3p and by inhibiting HDAC2.
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Comportamento Animal/efeitos dos fármacos , Lesões Encefálicas Traumáticas/complicações , Cinamatos/farmacologia , Histona Desacetilase 2/metabolismo , Transtornos da Memória/prevenção & controle , MicroRNAs/genética , Transmissão Sináptica/efeitos dos fármacos , Animais , Histona Desacetilase 2/genética , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The generalized nonlinear Schrödinger model with distributed dispersion, nonlinearity, and gain or loss is considered and the explicit, analytical solutions describing the dynamics of bright solitons on a continuous-wave background are obtained in quadratures. Then, the generation, compression, and propagation of pulse trains are discussed in detail. The numerical results show that solitons can be compressed by choosing the appropriate control fiber system, and pulse trains generated by modulation instability can propagate undistorsted along fibers with distributed parameters by controlling appropriately the energy of each pulse in the pulse train.
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We consider the inhomogeneous higher-order nonlinear Schrodinger equation and explicitly present exact combined solitary wave solutions that can describe the simultaneous propagation of bright and dark solitary waves in a combined form in inhomogeneous fiber media or in optical communication links with distributed parameters. Furthermore, we analyze the features of the solutions, and numerically discuss the stabilities of these solitary waves under slight violations of the parameter conditions and finite initial perturbations. The results show that there exist combined solitary wave solutions in an inhomogeneous fiber system, and the combined solitary wave solutions are stable under slight violations of the parameter conditions and finite initial perturbations. Finally, the interaction between two neighboring combined solitary waves is numerically discussed.
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We investigate one-dimensional complex Ginzburg-Landau equation with higher-order terms and discuss their influences on the multiplicity of solutions. An exact analytic front solution is presented. By stability analysis for the original partial differential equation, we derive its necessary stability condition for amplitude perturbations. This condition together with the exact front solution determine the region of parameter space where the uniformly translating front solution can exist. In addition, stable pulses, chaotic pulses, and attenuation pulses appear generally if the parameters are out of the range. Finally, applying these analysis into the optical transmission system numerically we find that the stable transmission of optical pulses can be achieved if the parameters are appropriately chosen.
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We construct the Lax pair for a higher-order nonlinear Schrödinger equation that includes terms accounting for the third-order dispersion, the self-steepening effect, and the delayed nonlinear response effect. Two exact analytic solutions that describe (i) modulation instability and (ii) soliton propagation on a continuous wave background are obtained by using the Darboux transformation. In addition, we analyze the amplification-absorption and quintic nonlinearity effects on the second solution in the adiabatic approximation.
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We investigate the generalized higher-order nonlinear Schrödinger equation with variable coefficients under two sets of parametric conditions. The exact one-soliton solution is presented by the ansatz method for one set of parametric conditions. For the other, exact multisoliton solutions are presented by employing the Darboux transformation based on the Lax pair. As an example, we consider a soliton control system, and the results show that the soliton control system may relax the limitations to parametric conditions. The stability of the solution is discussed numerically; the results reveal that finite initial perturbations, such as amplitude, chirp, or white noise, could not influence the main character of the solution. In addition, the evolution of a quite arbitrary Gaussian pulse and the interaction between neighboring pulses have been studied in detail.
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Narrow optical dip solutions are investigated when, besides self-phase modulation and group velocity dispersion, also third-order dispersion, nonlinear dispersion, and stimulated Raman scattering are taken into account. By using the inverse scattering transform for the higher-order optical nonlinear Schrödinger (HNLS) equation under Hirota parameter conditions, the dark N-soliton solution is constructed. The explicit forms of the one- and two-soliton solutions are investigated in detail. The results show an interesting property of the gray two-soliton solution. Two gray dips do not interact provided their modulation depths are appropriately chosen. In addition, when generalizing the HNLS equation (to regions beyond the Hirota parameter conditions), it can be shown that also quite stable generalized two-dip solitary wave solutions exist. The latter, although not belonging to integrable systems, approximately preserve most of the interesting properties detected for the integrable Hirota equation.
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We consider the averaged dispersion-managed (DM) fiber system equation, which governs the dynamics of the core of the DM solitons. For a special case of such a system equation, we derive the exact soliton solutions using the Darboux transformation. Further, we discuss the interaction scenario between two neighboring solitons. Finally, we derive a dark soliton solution for such a system by assuming an ansatz, and the interaction between neighboring dark solitons is discussed.
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AIM: This study aims to investigate the influence of different surgical timing on outcome of patients with aneurysmal subarachnoid hemorrhage and to explore the surgical techniques for ruptured intracranial aneurysms. MATERIAL AND METHODS: The clinical data were from 327 cases. 304 cases of the surgical group were further assigned to early surgery (89 cases), intermediate surgery(164 cases) and delayed surgery(51 cases) according to the surgical timing. The other 23 cases were the nonsurgical group. The ultimate outcome of all cases was graded according to the Glasgow Outcome Scale. After the cases of the no-surgical group were re-assigned to different surgical subgroups according to the rebleeding time, the ultimate outcome was graded once more. RESULTS: There was no significant difference among the 3 groups' pre-operative clinical data. After re-assigning the cases of no-surgical group to the different surgical subgroups, there was no significant difference among the 3 groups' preooperative clinical data, while the ultimate outcome grades of early surgery (3.6 ± 1.8) and intermediate surgery (3.5 ± 2.2) were superior to that of delayed surgery (2.9 ± 2.8). CONCLUSION: This retrospective study has demonstrated that early surgery can not only prevent re-rupture of aneurysm to decrease mortality rate but also improve the ultimate outcome.
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Aneurisma Roto/cirurgia , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos , Hemorragia Subaracnóidea/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Escala de Resultado de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
Isoliquiritigenin (ISL), a member of the flavonoids, has been demonstrated to possess antitumor activity in various cancer cell lines in vitro and in vivo. In this study, we investigated the antitumor effects of ISL on U87 glioma cells in vitro. As determined by MTT assay, ISL inhibited the proliferation of U87 cells in a time-dependent and dose-dependent manner. The results of fluorescence-activated cell sorting (FACS) analysis suggested that ISL induced the apoptosis of the U87 cells and blocked cell cycle progression at the S and G2/M phases. Moreover, it was identified that ISL induced the apoptosis of the U87 cells in a caspase-dependent manner. Although treatment with the pan-caspase inhibitor Z-VAD-FMK efficiently blocked the ISL-induced caspase activation, it did not eliminate the ISL-induced cell death. Further examination using western blot analysis revealed that ISL upregulated p21/WAF1 and p27. These results indicate that cell cycle arrest and the caspase-mediated apoptosis pathway may participate in the antiproliferative activity of ISL in U87 cells by regulating the expression of specific molecules.
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Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Chalconas/toxicidade , Clorometilcetonas de Aminoácidos/farmacologia , Antineoplásicos/química , Caspases/química , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Chalconas/química , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Humanos , Regulação para Cima/efeitos dos fármacosRESUMO
OBJECTIVE: Awake craniotomy for brain tumor resection has the benefit of avoiding a general anesthetic and decreasing associated costs (e.g., intensive care unit beds and intravenous line insertion). In low- and middle-income countries, significant resource limitations for the system and individual make awake craniotomy an ideal tool, yet it is infrequently used. We sought to determine if awake craniotomy could be effectively taught and implemented safely and sustainably in low- and middle-income countries. METHODS: A neurosurgeon experienced in the procedure taught awake craniotomy to colleagues in China, Indonesia, Ghana, and Nigeria during the period 2007-2012. Patients were selected on the basis of suspected intraaxial tumor, absence of major dysphasia or confusion, and ability to tolerate the positioning. Data were recorded by the local surgeons and included preoperative imaging, length of hospital admission, final pathology, postoperative morbidity, and mortality. RESULTS: Awake craniotomy was performed for 38 cases of suspected brain tumor; most procedures were completed independently. All patients underwent preoperative computed tomography or magnetic resonance imaging. In 64% of cases, patients remained in the hospital <10 days. The most common pathology was high-grade glioma, followed by meningioma, low-grade glioma, and metastasis. No deaths occurred, and no case required urgent intubation. The most common perioperative and postoperative issue was seizure, with 1 case of permanent postoperative deficit. CONCLUSIONS: Awake craniotomy was successfully taught and implemented in 6 neurosurgical centers in China, Indonesia, Ghana, and Nigeria. Awake craniotomy is safe, resource-sparing, and sustainable. The data suggest awake craniotomy has the potential to significantly improve access to neurosurgical care in resource-challenged settings.
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Craniotomia/métodos , Neurocirurgia/educação , Procedimentos Neurocirúrgicos/métodos , Vigília , África , Anestesia , Ásia , Neoplasias Encefálicas/cirurgia , China/epidemiologia , Craniotomia/estatística & dados numéricos , Países em Desenvolvimento , Gana/epidemiologia , Recursos em Saúde , Humanos , Indonésia/epidemiologia , Imageamento por Ressonância Magnética , Neurocirurgia/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Nigéria/epidemiologia , Seleção de Pacientes , Assistência Perioperatória , Cuidados Pós-Operatórios , Ensino , Tomografia Computadorizada por Raios XRESUMO
There is a great uncertainty of greenhouse gas (GHG) reduction and nitrogen conservation from the full process of sludge composting and land application of compost in China due to the lack of emission data of GHG such as N2O and CH4 and ammonia (NH3). The purpose of this study is to get emission characteristics of GHGs and NH3 from the full process with on-site observation. Results showed that the total GHG emission factor from full process of the turning windrow (TW) system (eCO2/dry sludge, 196.21 kg x t(-1)) was 1.61 times higher of that from the ATP system. Among the full process, N2O was mostly from the land application of compost, whereas CH4 mainly resulted from the sludge composting. In the sludge composting of ATP, the GHG emission equivalence of the ATP (eCO2/dry sludge, 12.47 kg x t(-1) was much lower than that of the TW (eCO2/dry sludge, 86.84 kg x t(-1)). The total NH3 emission factor of the TW (NH3/dry sludge, 6.86 kg x t(-1)) was slightly higher than that of the ATP (NH3/dry sludge, 6.63 kg x t(-1)). NH3 was the major contributor of nitrogen loss in the full process. During the composting, the nitrogen loss as NH3 from both TW and ATP was nearly the same as 30% of TN loss from raw materials, and the N and C loss caused by N2O and CH4 were negligible. These results clearly showed that the ATP was a kind of environmentally friendly composting technology.
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Amônia/análise , Efeito Estufa , Esgotos , Dióxido de Carbono/análise , China , Gases/análise , Metano/análise , Nitrogênio/análise , Óxido Nitroso/análiseRESUMO
OBJECTIVE: To compare the therapeutic effects of transcutaneous electrical point stimulation and medication on functional dyspepsia. METHODS: Two hundred and fifty cases were randomly divided into an observation group and a control group, 125 cases in each group. The observation group was treated with transcutaneous electrical acupoint stimulation and oral administration of placebo, transcutaneous electrical stimulated at Zusanli (ST 36), Liangmen (ST 21), Taichong (LR 3) etc. The control group was treated with oral administration of Mosapride citrate dispersible tablets, Domperidone and Omeprazole and the placebo treatment of transcutaneous electrical acupoint stimulation, the stimulated position was 3-4 cm to the selected points of the observation group, the amount of the stimulation did not reach the treatment amount. The symptom score, the plasma motilin (MTL) concentration and the somatostatin (SS) concentration were observed before and after treatment of 3 courses. RESULTS: All symptom scores after treatment were lower than that before treatment in the two groups, the scores of the upper abdominal pain, acid regurgitation, belching and abdominal distention in the observation group were significantly lower than that in the control group (P < 0.05, P < 0.01); the treatments of both two groups can increase the plasma MTL concentration and decrease the SS concentration (both P < 0.001), and the plasma MTL concentration in the observation group was significantly higher than that in the control group (P < 0.01), and the SS concentration was significantly lower than that in the control group (P < 0.05). CONCLUSION: Transcutaneous electrical point stimulation can more reduce the symptoms of upper abdominal pain, acid regurgitation, belching and abdominal distention, etc. in the functional dyspepsia patients than medication treatment, and can increase the concentration of the plasma MTL and decrease the SS concentration, thus to improve the gastrointestinal motility.
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Pontos de Acupuntura , Dispepsia/terapia , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto , Idoso , Benzamidas/administração & dosagem , Benzamidas/uso terapêutico , Domperidona/administração & dosagem , Domperidona/uso terapêutico , Dispepsia/sangue , Dispepsia/fisiopatologia , Feminino , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Morfolinas/administração & dosagem , Morfolinas/uso terapêutico , Motilina/sangue , Omeprazol/administração & dosagem , Omeprazol/uso terapêutico , Somatostatina/sangue , Resultado do TratamentoRESUMO
OBJECTIVE: To search for an effective therapy for infantile cold. METHODS: Two hundred and fifty-five cases were randomly divided into a laser group (n = 130) and a medication group (n = 125). The laser group were treated with lower energy He-Ne laser radiation at Tiantu (CV 22), Renying (ST 9), Dazhui (CV 14), Fengmen (BL 12), etc. and the medication group were treated mainly with oral administration of Amantadine tablets. The therapeutic effect was assessed after treatment of 5 days. RESULTS: The laser group in alleviation of cough, nasal obstruction, rhinorrhea, sputum sound were significantly better than the medication group (P < 0.001, P < 0.01); the cured rate was 68.5% in the laser group and 42.4% in the medication group, the former being better than the latter (P < 0.001). CONCLUSION: The low energy He-Ne laser acupoint radiation has a significant therapeutic effect on infantile cold.
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Pontos de Acupuntura , Resfriado Comum/terapia , Terapia com Luz de Baixa Intensidade , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
Ultrashort laser pulse propagation in a generalized nonconservative system is considered. Slopes appearing in the form of the third-order time derivative for narrow pulse widths, nonlinear dispersion, and self-frequency shift arising from stimulated Raman scattering are taken into account. An exact analytical solitonlike solution is presented for a femtosecond solitary laser pulse. The stability of the latter has been shown numerically by applying perturbations in amplitude and chirp, as well as adding white noise. The results indicate stability in a broad parameter range. In addition, we have also found that the solution acts as an attractor when starting with a quite arbitrary Gaussian pulse as an initial condition.