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1.
Micromachines (Basel) ; 15(4)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38675240

RESUMO

Based on the theory of reliability enhancement testing technology, this study used a variety of testing combinations and finite element simulations to analyze the stress-strain properties of 3D packaging storage modules and then evaluated its operating and destruction limits during temperature cycling tests (-65 °C~+150 °C) for the purpose of identifying the weak points and failure mechanisms affecting its reliability. As a result of temperature cycling ultimate stress, 3D packaging storage devices can suffer from thermal fatigue failure in the case of abrupt temperature changes. The cracks caused by the accumulation of plastic and creep strains can be considered the main factors. Crack formation is accelerated by the CTE difference between the epoxy resin and solder joints. Moreover, the finite element simulation results were essentially the same as the testing results, with a deviation occurring within 10%.

2.
ACS Appl Mater Interfaces ; 16(4): 5158-5167, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38238929

RESUMO

Flow chemistry provides a neo-orientation for the research and development of chemical technology, in which heterogeneous continuous catalysis based on packed beds can realize rapid separation and recycling. However, options for heterogeneous catalysts are still limited. In this work, we gradually grow covalent organic frameworks (COFs, TpBpy) on the surface of a silica gel (SiO2)-supported substrate to obtain a stable copper(I)-chelated high-loading heterogeneous catalyst (SiO2@CuI-TpBpy). SiO2@CuI-TpBpy shows high catalytic activity in three-component Huisgen 1,3-dipolar cycloaddition, giving the corresponding triazoles with excellent yields and reposeful recyclability under batch conditions. The structures of the catalysts remain steady, and the copper contents are basically unchanged after five cycles. Then, the catalysts are successfully applied for three-component heterogeneous catalysis in a one-pot continuous flow to prepare rufinamide in 89% yield for 24 h stably and efficiently with mere traces of copper ions remaining. More importantly, the catalytic system reveals a minuscule effect of catalyst particle size on internal diffusion. This COF encapsulation strategy presents a new possibility for the design of industrial heterogeneous catalysts with high metal loading and low internal diffusion resistance.

3.
J Phys Chem B ; 128(1): 208-221, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38113228

RESUMO

Aqueous solutions of magnesium chloride (MgCl2(aq)) are often used to test advances in the theory of electrolyte solutions because they are considered an ideal strong 2:1 electrolyte. However, there is evidence that some ion association occurs in these solutions, even at low concentrations. Even a small ion-pairing constant can have a significant impact on the chemical speciation of ions, so it is important to determine whether ion pairing actually occurs. In this study, MgCl2(aq) with concentrations ranging from 1 to 35% was studied using three methods: X-ray scattering (XRS) with the Shanghai Synchrotron Radiation Facility (SSRF) and silver-anode laboratory sources, Raman spectroscopy, and molecular dynamics (MD) simulations with the COMPASS-II and Madrid force fields. XRS results were analyzed in the framework of PDF theory to obtain the reduced structure function F(Q) and the reduced pair distribution function G(r). The F(Q) values from synchrotron radiation and laboratory sources both showed that the tetrahedral hydrogen bonds in bulk water were destroyed with the increased MgCl2 concentration. The results of G(r) indicated that the main peaks centered at 2.05 and 2.80 Å can be ascribed to the interactions of Mg-O and O-O, respectively. The peak at 3.10 Å is attributed to the combined effect of O-O and Cl-O. By comparing the structural information on MgCl2 solution obtained from the two light sources, it was found that both SSRF and silver-anode laboratory sources can reflect the above-mentioned structural information on MgCl2 solution. The radial distribution function (RDF) obtained from MD simulations of MgCl2 solutions assigned the peaks at 2.0, 2.8, and 3.2 Å to the Mg-O, O-O, and Cl-O interatomic pairs, respectively. The decrease in the O-O coordination number confirms that the hydrogen-bonding network of water is disrupted by increasing MgCl2 observed by X-ray scattering. The proportion of Mg-Cl contact ion pairs gradually increases with MgCl2 concentration as does the coordination number. Raman spectroscopy results show that the bond type changes from double donor double acceptor (DDAA) to single donor-single acceptor (DA) with increasing concentration, providing explicit details of the hydrogen-bond evolution in the aqueous solution.

4.
Micromachines (Basel) ; 14(11)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-38004918

RESUMO

In this work, environmentally friendly and low-cost passive electrical components (PECs) are manufactured based on composites consisting of cotton fabrics soaked with solutions of silicone oil and different amounts of iron oxides microfibers (µFe). The µFe consists of a mixture of three phases: hematite (α-Fe2O3), maghemite (γ-Fe2O3), and magnetite (Fe3O4). The equivalent electrical capacitance (Cp) and resistance (Rp) of PECs are measured as a function of magnetic flux density B in a static and pulsed magnetic field superimposed on an alternating electric field of frequency 1 kHz. The relative variation in the hysteresis curves for both Cp and Rp are obtained by measuring them in the ascending and then the descending mode of B. We show that all these three quantities are sensibly influenced by the volume fractions of µFe and by the values of B. The main influence on this behavior is attributed to the semiconductor properties of the α-Fe2O3 and γ-Fe2O3 components of the oxide microfibers. In addition, it is found that at B≃ 175 mT, the maximum relative variance of the hysteresis curve is about 3.35% for Cp and 3.18 % for Rp. When a pulsed magnetic field is used, it is shown that Cp and Rp closely follow the variation in the magnetic field. Thus, the resulting electrical properties of PECs, together with the fast response to the application of pulsed magnetic fields, make them useful in the fabrication of various devices, such as electric, magnetic, and deformation fields, or mechanical stress sensors with applications in protection against electromagnetic smog, healthcare monitoring, or for human-machine interfacing.

5.
Water Sci Technol ; 88(5): 1317-1331, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37771229

RESUMO

Selective electrodialysis is a promising approach to recovering K+ from complex coexisting ionic systems. In this study, the effects of current density, the concentration of K+ and Mg2+, as well as the operating temperature on the separation process of K+ and Mg2+ were explored to investigate the competitive migration of mono- and multivalent ions, offering a guide for the design of selective electrodialysis process, and therefore obtain the desired aqueous solutions containing K+ and Mg2+. The results show that ion concentration played a critical role in determining the selectivity of separation between K+ and Mg2+. High concentrations of K+ and Mg2+ led to a decrease in selectivity but the effect of concentration of K+ on selectivity was more pronounced. Although higher current density increased the flux of ions, their impact on separation selectivity was minimal. Furthermore, higher temperature increased the flux of ions but resulted in a decrease of K+ proportion in the solution. Overall, this study provides good guidance for studying the competitive migration of mono- and multivalent ions and the high-value recycling of potassium resources.

6.
J Surg Oncol ; 128(8): 1219-1226, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37638392

RESUMO

OBJECTIVE: To study the timing of surgery after a recent Omicron variant infection, to provide a reference for policymakers, clinicians, and patients. METHODS: This single-center propensity-matched analysis was designed and reported according to the EQUATOR-STROBE guidelines. Patients recovering from COVID-19 infection were divided into three groups based on the period from disappearance of respiratory symptoms to surgery: ≤7 days, 8-14 days, and >14 days groups. Outcome measures included postoperative respiratory complications, vascular thrombosis, myocardial infarction, ischemic stroke, and mortality. RESULTS: Between August 1 and December 31, 2022, 9023 surgical procedures were performed, of which 7490 surgeries met the inclusion criteria. Propensity matching resulted in a final cohort of 227 patients recovered from COVID-19 and 2043 SARS-CoV-2 negative patients. Compared with the SARS-CoV-2 negative group, the incidence of postoperative respiratory complications was significantly higher (15.91% vs. 6.71%, p = 0.028) only in the ≤7 days group. There were no statistically significant differences in the other 30-day outcomes between the SARS-CoV-2 negative and the three COVID-19 recovery groups. CONCLUSIONS: Patients who have recovered from mild COVID-19 may be eligible for elective surgery at least 7 days after recovery, since they do not have an increased risk of postoperative complications or mortality within 30 days.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/etiologia , SARS-CoV-2 , Procedimentos Cirúrgicos Eletivos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
7.
Molecules ; 28(12)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37375220

RESUMO

Electrochemical reduction of nitrate has broad application prospects. However, in traditional electrochemical reduction of nitrate, the low value of oxygen produced by the anodic oxygen evolution reaction and the high overpotential limit its application. Seeking a more valuable and faster anodic reaction to form a cathode-anode integrated system with nitrate reaction can effectively accelerate the reaction rate of the cathode and anode, and improve the utilization of electrical energy. Sulfite, as a pollutant after wet desulfurization, has faster reaction kinetics in its oxidation reaction compared to the oxygen evolution reaction. Therefore, this study proposes an integrated cathodic nitrate reduction and anodic sulfite oxidation system. The effect of operating parameters (cathode potential, initial NO3--N concentration, and initial SO32--S concentration) on the integrated system was studied. Under the optimal operating parameters, the nitrate reduction rate in the integrated system reached 93.26% within 1 h, and the sulfite oxidation rate reached 94.64%. Compared with the nitrate reduction rate (91.26%) and sulfite oxidation rate (53.33%) in the separate system, the integrated system had a significant synergistic effect. This work provides a reference for solving nitrate and sulfite pollution, and promotes the application and development of electrochemical cathode-anode integrated technology.

8.
Microsyst Nanoeng ; 9: 50, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123536

RESUMO

The Cu-filling process in through-silicon via (TSV-Cu) is a key technology for chip stacking and three-dimensional vertical packaging. During this process, defects resulting from chemical-mechanical planarization (CMP) and annealing severely affect the reliability of the chips. Traditional methods of defect characterization are destructive and cumbersome. In this study, a new defect inspection method was developed using Mueller matrix spectroscopic ellipsometry. TSV-Cu with a 3-µm-diameter and 8-µm-deep Cu filling showed three typical types of characteristics: overdishing (defect-OD), protrusion (defect-P), and defect-free. The process dimension for each defect was 13 nm. First, the three typical defects caused by CMP and annealing were investigated. With single-channel deep learning and a Mueller matrix element (MME), the TSV-Cu defect types could be distinguished with an accuracy rate of 99.94%. Next, seven effective MMEs were used as independent channels in the artificial neural network to quantify the height variation in the Cu filling in the z-direction. The accuracy rate was 98.92% after training, and the recognition accuracy reached 1 nm. The proposed approach rapidly and nondestructively evaluates the annealing bonding performance of CMP processes, which can improve the reliability of high-density integration.

9.
Polymers (Basel) ; 15(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37112100

RESUMO

Thermoplastic starch was blended with commercially available biodegradable polyesters of poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) for its improved performance and processability. The morphology and elemental composition of these biodegradable polymer blends were observed by scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively, while their thermal properties were analyzed using thermogravimetric analysis and differential thermal calorimetry. For rheological analysis, the steady shear and dynamic oscillation tests of three samples at various temperatures were investigated using a rotational rheometer. All three samples exhibited significant shear thinning at all measured temperatures, and their shear viscosity behavior was plotted using the Carreau model. The frequency sweep tests showed that the thermoplastic starch sample exhibited a solid state at all temperatures tested, whereas both starch/PBAT and starch/PBAT/PLA blend samples exhibited viscoelastic liquid behavior after the melting temperature such that their loss modulus at low frequencies was greater than the storage modulus, and inversion occurred at high frequencies (storage modulus > loss modulus).

10.
Molecules ; 27(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36080342

RESUMO

The microstructure of a mixed KCl and K2SO4 aqueous solution was studied using X-ray scattering (XRS), Raman spectroscopy, and molecular dynamics simulation (MD). Reduced structure functions [F(Q)], reduced pair distribution functions [G(r)], Raman spectrum, and pair distribution functions (PDF) were obtained. The XRS results show that the main peak (r = 2.81 Å) of G(r) shifted to the right of the axis (r = 3.15 Å) with increased KCl and decreased K2SO4. The main peak was at r = 3.15 Å when the KCl concentration was 26.00% and the K2SO4 concentration was 0.00%. It is speculated that this phenomenon was caused by the main interaction changing, from K-OW (r = 2.80 Å) and OW-OW (r = 2.80 Å), to Cl−-OW (r = 3.14 Å) and K+-Cl− (r = 3.15 Å). According to the trend of the hydrogen bond structure in the Raman spectrum, when the concentration of KCl was high and K2SO4 was low, the destruction of the tetrahedral hydrogen bond network in the solution was more serious. This shows that the destruction strength of the anion to the hydrogen bond network structure in solution was Cl− > SO42−. In the MD simulations, the coordination number of OW-OW decreased with increasing KCl concentration, indicating that the tetrahedral hydrogen bond network was severely disrupted, which confirmed the results of the Raman spectroscopy. The hydration radius and coordination number of SO42− in the mixed solution were larger than Cl−, thus revealing the reason why the solubility of KCl in water was greater than that of K2SO4 at room temperature.


Assuntos
Simulação de Dinâmica Molecular , Análise Espectral Raman , Análise Espectral Raman/métodos , Sulfatos , Água/química , Raios X
11.
Micromachines (Basel) ; 13(2)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35208425

RESUMO

Optically clear adhesive (OCA) has been widely used in flexible devices, where wavy stripes that cause troublesome long-term reliability problems often occur. The complex mechanical behavior of OCA should be studied, as it is related to the aforementioned problems. Therefore, it is necessary to establish reasonable mechanical constitutive models for deformation and stress control. In this work, hyperelastic and viscoelastic mechanical tests were carried out systematically and relative constitutive models of OCA material were established. We found that temperature has a great influence on OCA's mechanical properties. The stress and modulus both decreased rapidly as the temperature increased. In the static viscoelasticity test, the initial stress at 85 °C was only 12.6 kPa, 57.4% lower than the initial stress at 30 °C. However, in the dynamic test, the storage modulus monotonically decreased from 1666.3 MPa to 0.6628 MPa as the temperature rose, and the decline rate reached the maximum near the glass transition temperature (Tg = 0 °C). The test data and constitutive models can be used as design references in the manufacturing process, as well as for product reliability evaluation.

12.
Sci Total Environ ; 820: 153272, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35074375

RESUMO

Carbon dioxide (CO2) capture coupled with further mineralization in high value-added form is a great challenge for carbon capture utilization and storage (CCUS) processes. In this work, a bipolar membrane electrodialysis (BMED) technique integrated with crystallization chamber was proposed to utilize CO2-derived carbonates and the residual magnesium resource from seawater to produce functional nesquehonite. To ensure the stable CO2 storage and magnesium extraction by BMED process, the metastable zone during nesquehonite crystallizing was first measured to modulate crystallization rate, obtain high-quality crystal products and inhibit membrane fouling states. Subsequently, the effects of current density, temperature, and CO2 flow rate during the whole BMED-crystallization process were further investigated. The increase in current density and temperature was conducive for the extraction of magnesium while the enlarged gas flow rate induced higher absorption of CO2. Under the current density at 22 A/m2, CO2 flow rate at 50 mL/min and temperature at 30 °C, the optimal carbon absorption ratio and the magnesium extraction ratio reached 50.85% and 56.71%, respectively. Under this condition, the explosion nucleation of the nesquehonite was effectively avoided to inhibit membrane fouling and the generation of magnesium hydroxide was depressed to obtain the target product nesquehonite. This study on simultaneous carbon capture and magnesium utilization provides theoretical guidance for the industrial green storage of CO2 and development of valuable magnesium products.


Assuntos
Dióxido de Carbono , Magnésio , Dióxido de Carbono/química , Carbonatos , Magnésio/química , Água do Mar/química , Temperatura
13.
ASN Neuro ; 13: 17590914211038441, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34596444

RESUMO

Destabilization of blood vessels by the activities of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) following intracerebral hemorrhage (ICH) has been considered the main causes of aggravated secondary brain injury. Here, we show that tumor necrosis factor superfamily-15 (TNFSF15; also known as vascular endothelial growth inhibitor), an inhibitor of VEGF-induced vascular hyper-permeability, when overexpressed in transgenic mice, exhibits a neuroprotective function post-ICH. In this study, we set-up a collagenase-induced ICH model with TNFSF15-transgenic mice and their transgene-negative littermates. We observed less lesion volume and neural function perturbations, together with less severe secondary injuries in the acute phase that are associated with brain edema and inflammation, including vascular permeability, oxidative stress, microglia/macrophage activation and neutrophil infiltration, and neuron degeneration, in the TNFSF15 group compared with the littermate group. Additionally, we show that there is an inhibition of VEGF-induced elevation of MMP-9 in the perihematomal blood vessels of the TNFSF15 mice following ICH, concomitant with enhanced pericyte coverage of the perihematomal blood vessels. These findings are consistent with the view that TNFSF15 may have a potential as a therapeutic agent for the treatment of secondary injuries in the early phase of ICH.


Assuntos
Edema Encefálico , Lesões Encefálicas , Animais , Edema Encefálico/etiologia , Permeabilidade Capilar , Hemorragia Cerebral/complicações , Modelos Animais de Doenças , Camundongos , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Fator A de Crescimento do Endotélio Vascular
14.
ACS Appl Mater Interfaces ; 13(37): 44806-44813, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34519198

RESUMO

Covalent organic frameworks (COFs) have aroused extensive attention from various fields owing to their numerous advantages, including permanent porosity, high crystallinity, strong robustness, and well-ordered channels. However, the poor processability of the crystallite powder has greatly impeded their further utilization in many advanced devices and frontier areas. In this work, we fabricate a series of COF films using an interfacial polymerization strategy at a liquid-liquid interface under ambient conditions. The as-synthesized freestanding films are continuous, flexible, and defect-free and have large areas of up to 4 × 6 cm2. In addition, the pore sizes of these COF films can be well controlled based on the principle of reticular chemistry. These films exhibit high chemical stability even in acidic and basic aqueous solutions. More significantly, the highly robust COF films can serve as a nanofiltration membrane for efficient separation of pollutant molecules with different dimensions. These films show high selectivity for the separation of mixed molecule feed and excellent recyclability without a significant loss in the rejection rate.

15.
Phys Fluids (1994) ; 32(12): 125102, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33362402

RESUMO

Coronavirus disease 2019 has become a global pandemic infectious respiratory disease with high mortality and infectiousness. This paper investigates respiratory droplet transmission, which is critical to understanding, modeling, and controlling epidemics. In the present work, we implemented flow visualization, particle image velocimetry, and particle shadow tracking velocimetry to measure the velocity of the airflow and droplets involved in coughing and then constructed a physical model considering the evaporation effect to predict the motion of droplets under different weather conditions. The experimental results indicate that the convection velocity of cough airflow presents the relationship t -0.7 with time; hence, the distance from the cougher increases by t 0.3 in the range of our measurement domain. Substituting these experimental results into the physical model reveals that small droplets (initial diameter D ≤ 100 µm) evaporate to droplet nuclei and that large droplets with D ≥ 500 µm and an initial velocity u 0 ≥ 5 m/s travel more than 2 m. Winter conditions of low temperature and high relative humidity can cause more droplets to settle to the ground, which may be a possible driver of a second pandemic wave in the autumn and winter seasons.

16.
ACS Appl Mater Interfaces ; 12(33): 37427-37434, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32538078

RESUMO

A porphyrin-based two-dimensional (2D) covalent organic framework (COF) was developed by a C4 + C4 topological diagram. It was constructed by the condensation of zinc 5,10,15,20-tetra(4-aminophenyl)porphyrin (TAPP) and zinc 5,10,15,20-tetra(4-formylphenyl)porphyrin (TFPP) under typical solvothermal conditions, leading to the formation of a porphyrin-based TAPP-TFPP-COF with tetragonal micropores at a size of 1.8 nm. The resultant crystalline framework exhibited high crystallinity, excellent stability, and good porosity. Resulting from the specific π-unit stacking columnar structure and excellent organic semiconducting property of porphyrins, the TAPP-TFPP-COF shows many promising applications in optoelectronics. Notably, after doping with iodine, the conductivity of this TAPP-TFPP-COF can be greatly enhanced from 1.12 × 10-10 to 1.46 × 10-7 S cm-1. Furthermore, the nanometer-thick TAPP-TFPP-COF films were obtained using a liquid-air interface growth strategy. A spectroscopic detection device was constructed using COF thin films which displayed highly selective sensitivity toward the near infrared irradiation at 700 nm with an on-off ratio of up to 2.8 × 104. This value ranks as the highest among other COF-based and metal-organic-framework-based semiconducting materials under similar conditions. These results illustrated the enormous potential of 2D porphyrin COFs for future applications in optoelectronic devices and constituted an important step toward the development of new types of functional crystalline materials.

17.
FASEB J ; 33(9): 10505-10514, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31242765

RESUMO

Hemangioblastoma (HB) is an abnormal intracranial buildup of blood vessels that exhibit a great potential for hemorrhage. Surgical options are limited, and few medications are available for treatment. We show here by immunohistochemical analysis that HB lesions display highly increased levels of VEGF expression and macrophage/microglia infiltration compared with those in normal brain tissues. In the meantime, TNF superfamily 15 (TNFSF15) (also known as vascular endothelial growth inhibitor), an antiangiogenic cytokine, is highly expressed in normal brain blood vessels but diminished in HB lesions. We set up a brain hemangioma model by using mouse bEnd.3 cells of a T antigen-transformed endothelial cell line that produce a large amount of VEGF. When implanted in mouse brains, these cells form lesions that closely resemble the pathologic characteristics of HB. Retroviral infection of bEnd.3 cells with TNFSF15 leads to inhibition of VEGF production and retardation of hemangioma formation. Similar results are obtained when wild-type bEnd.3 cells are implanted in the brains of transgenic mice overexpressing TNFSF15. Additionally, TNFSF15 treatment results in enhanced pericyte coverage of the blood vessels in the lesions together with reduced inflammatory cell infiltration and decreased hemorrhage. These findings indicate that the ability of TNFSF15 to counterbalance the abnormally highly angiogenic and inflammatory potential of the microenvironment of HB is of therapeutic value for the treatment of this disease.-Yang, G.-L., Han, Z., Xiong, J., Wang, S., Wei, H., Qin, T.-T., Xiao, H., Liu, Y., Xu, L.-X., Qi, J.-W., Zhang, Z.-S., Jiang, R., Zhang, J., Li, L.-Y. Inhibition of intracranial hemangioma growth and hemorrhage by TNFSF15.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Modelos Animais de Doenças , Células Endoteliais/transplante , Hemangioma/prevenção & controle , Hemorragias Intracranianas/prevenção & controle , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Animais , Apoptose , Proliferação de Células , Células Endoteliais/citologia , Hemangioma/metabolismo , Hemangioma/patologia , Humanos , Hemorragias Intracranianas/metabolismo , Hemorragias Intracranianas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Prognóstico , Células Tumorais Cultivadas , Microambiente Tumoral , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/administração & dosagem
18.
Chem Commun (Camb) ; 55(7): 977-980, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30608081

RESUMO

A photochemical reaction in which the imidazole ring is opened under UV irradiation to generate highly luminescent benzoylimino group by O2 has been discovered. This photochemical reaction displays great potential for applications that use a fluorescent probe as a oxygen sensor; it has a lowest detectable volume ratio of ∼0.2% and photo storage area.

19.
J R Soc Interface ; 12(113): 20150821, 2015 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-26701882

RESUMO

This paper elucidates the aerodynamic role of the dynamically changing wingspan in bat flight. Based on direct numerical simulations of the flow over a slow-flying bat, it is found that the dynamically changing wingspan can significantly enhance the lift. Further, an analysis of flow structures and lift decomposition reveal that the elevated vortex lift associated with the leading-edge vortices intensified by the dynamically changing wingspan considerably contributed to enhancement of the time-averaged lift. The nonlinear interaction between the dynamically changing wing and the vortical structures plays an important role in the lift enhancement of a flying bat in addition to the geometrical effect of changing the lifting-surface area in a flapping cycle. In addition, the dynamically changing wingspan leads to the higher efficiency in terms of generating lift for a given amount of the mechanical energy consumed in flight.


Assuntos
Quirópteros/fisiologia , Voo Animal/fisiologia , Modelos Biológicos , Asas de Animais/fisiologia , Animais , Quirópteros/anatomia & histologia , Asas de Animais/anatomia & histologia
20.
J Neurol Sci ; 330(1-2): 38-44, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23628469

RESUMO

INTRODUCTION: Elevated intracranial pressure (ICP) is generally observed in brain injury and intracerebral hemorrhage (ICH) patients and is consistently associated with poor neurological outcome. Intracranial pressure variability (IPV) is a better predictor of long-term neurological outcome than mean ICP in traumatic brain injury patients. However, whether IPV regulates functional outcome in ICH patients has not been investigated. In the present study, we investigated the relationship between IPV and functional outcome in ICH patients and determined whether IPV is a valid predictor of neurological outcome in ICH patients. METHODS: A consecutive series of 56 patients with ICH were enrolled in this study. These patients underwent surgical treatments and were planted with an ICP monitor. The ICP was continuously recorded for 7 days at one-hour intervals. The mean arterial blood pressure (MAP) and cerebral perfusion pressure (CPP) were also calculated. We used successive variation (SV) to represent IPV, which was calculated by averaging the difference in ICP between successive parameters. The short-term outcome was dichotomized into improved and deteriorated groups based on the changes in their Glasgow Coma Scale (GCS) score between admission and 30 days after admission. The long-term outcome was evaluated by Glasgow Outcome Scale (GOS) at 12 months after discharge from the hospital, and the patients were dichotomized into independent and dependent groups. RESULTS: The results showed that IPV was lower in the improved patient group and higher in patients with poorer outcome at 30 days after ICH. There was a significant positive correlation between SV and short-term neurological outcome. We also found the in-patient mortality was significantly increased in the high IPV patient group (P=0.02), which was divided by the cutoff point using receiver operating characteristic (ROC) curve analysis. The univariate correlation analysis demonstrated that the IPV levels were positively correlated with mean ICP (R(2)=0.652, P=0.000), while were negatively correlated with CPP (R(2)=0.426, P=0.000). Increases in SV of ICP were a predictor of 30-day poor short-term outcome, but not for 12-month long-term outcome after adjusting for the potential confounders in a multivariable logistic regression model. CONCLUSIONS: The results suggest that high IPV is correlated with poorer outcome in ICH patients. Managing the ICP at an appropriate level during the early phase after ICH may improve functional outcome in ICH patients.


Assuntos
Hemorragias Intracranianas/fisiopatologia , Pressão Intracraniana/fisiologia , Idoso , Algoritmos , Pressão Sanguínea/fisiologia , Estimulação Elétrica , Feminino , Escala de Coma de Glasgow , Escala de Resultado de Glasgow , Humanos , Hemorragias Intracranianas/complicações , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/fisiopatologia , Curva ROC , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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