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1.
Neuropsychiatr Dis Treat ; 20: 765-775, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577632

RESUMEN

Purpose: The SARS-CoV-2 infection cases are increasing rapidly in neuro-intensive care units (neuro-ICUs) at the beginning of 2023 in China. We aimed to characterize the prevalence, risk factors, and prognosis of critically ill patients treated in neuro-ICUs. Materials and Methods: In the prospective, multicenter, observational registry study, critically ill patients with intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), and traumatic brain injury (TBI) admitted to eight Chinese neuro-ICUs between Feb 16, 2023, to Apr 30, 2023 were enrolled for the study. Mortality and ICU stay day were used as the primary outcomes. Results: 131 patients were finally included and analyzed (mean age 60.36 years [SD 13.81], 64.12% male, 39.69% SARS-CoV-2 infected). The mortality is higher in the SARS-CoV-2 infection group without statistical signification (7.69% vs 5.06%, p>0.05). The length of stay (LOS) in neuro-ICUs was significantly longer among the SARS-CoV-2 infection patients (7(1-12) vs 4(1-8), p<0.01), with increased viral pneumonia occurrence (58.54% vs 7.32%, p<0.01). SARS-CoV-2 infection, surgery, and low GCS scores were independent risk factors for prolonged LOS, and respiratory/renal failure were independent risk factors for death. Conclusion: Based on the present neuro-ICU cohort, SARS-CoV-2 infection was a significant risk for the prolonged LOS of neuro-critically ill patients. Trial Registration: Registered with Chictr.org.cn (ChiCTR2300068355) at 16 February 2023, Prospective registration. https://www.chictr.org.cn/showproj.html?proj=188252.

3.
Chaos ; 32(1): 013127, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35105143

RESUMEN

Multistability is a special issue in nonlinear dynamics. In this paper, a three-dimensional autonomous memristive chaotic system is presented, with interesting multiple coexisting attractors in a nested structure observed, which indicates the megastability. Furthermore, the extreme event is investigated by local riddled basins. Based on Helmholtz's theorem, the average Hamiltonian energy with respect to initial-dependent dynamics is calculated and the energy transition explains the occurrence mechanisms of the megastability and the extreme event. Finally, by configuring initial conditions, multiple coexisting megastable attractors are captured in PSIM simulations and FPGA circuits, which validate the numerical results.

4.
Adv Colloid Interface Sci ; 279: 102142, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32244063

RESUMEN

The rare-earth elements (REE), which encompass the fifteen metallic elements of the lanthanoid series of the periodic table, yttrium and occasionally scandium, have gained enormous public, economic and scientific attention in recent years. These elements, which have been found in over 250 minerals, are of high economic and strategic importance to many high-technology industries. As such they have been designated as critical materials by several countries and many new deposits are being developed. Rare-earth mineral (REM) deposits can be broadly classified into four geological environments: carbonates, alkaline/peralkaline igneous rocks, placers and ion adsorption clays. Apart from ion adsorption clay deposits, which require no mineral processing steps, froth flotation is the most applied beneficiation technique. This paper reviews the flotation of REM, covering their surface chemical properties as well as the various flotation reagents which have been employed.

5.
PLoS One ; 14(1): e0209888, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30653532

RESUMEN

A terrestrial laser scanner is a fast, high-precision data acquisition device, which has been applied more and more to the research area of forest inventory. In this study, a type of automated low-cost terrestrial laser scanner was designed and implemented based on a SICK LMS-511 two-dimensional laser scanning sensor and a stepper motor. The new scanner was named BEE(developed by the department of Electronic Engineering, Beijing Forestry University), which can scan the forest trees in three dimensions. The BEE scanner and its supporting software are specifically designed for forest inventory. The specific software was developed to smoothly control the BEE scanner and to acquire the data, including the angular data, range data, and intensity data, and the data acquired by the BEE scanner could be processed into point cloud data, a range map, and an intensity map. Based on the point cloud data, the trees were detected by a single slice of the single scan in a plot, and the local ground plane was fitted for each detected tree. Then the diameter at breast height (DBH), tree height, and tree position could be estimated automatically by using the specific software. The experiments have been performed by using the BEE scanner in an artificial ginkgo forest which was located in the Haidian District of Beijing. Four 10 m × 10 m square plots were selected for the experiments. The BEE scanner scanned in the four plots and acquired the single-scan data, respectively. The DBH, tree height, and tree position of the trees in the four plots were estimated and analyzed. For comparison, manually-measured data was also collected in the four plots. The trunk detection rate for all four plots was 92.75%; the root mean square error of the DBH estimation was 1.27 cm; the root mean square error of the tree height estimation was 0.24 m; and the tree position estimation was in line with the actual position. The scanner also was tested in more natural forest in the JiuFeng Forest Park. Two plots with a radius of 5 meters were scanned. Eleven trees in the plot with a flat ground were detected and DBH were estimated. But tree detection was failed in the other plot because of the undulating ground. Experimental results show that the BEE scanner can efficiently estimate the structure parameters of plantation trees and has good potential in practical applications of forest inventory.


Asunto(s)
Biometría/instrumentación , Biometría/métodos , Agricultura Forestal/métodos , Fenómenos Ecológicos y Ambientales , Bosques , Rayos Láser , Luz , Árboles/crecimiento & desarrollo
6.
Langmuir ; 33(13): 3200-3207, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28319401

RESUMEN

Frothers, a class of surfactants, are widely employed in froth flotation to aid the generation of small bubbles. Their action is commonly explained by their ability to hinder coalescence. There are occasional references suggesting that the frother may also play a role in the initial breakup of the injected air mass. This work investigates the possible effect of the frother on breakup by monitoring air bubbles produced quasi-statically at an underwater capillary. Under this condition, breakup is isolated from coalescence and an impact of frothers on the detached bubble can be ascribed to an impact on breakup. The breakaway process was monitored by an acoustic technique along with high-speed cinematography. The results showed that the presence of frothers did influence the breakaway process and that the acoustic technique was able to detect the impact. It was demonstrated that the acoustic frequency and acoustic damping ratio depend upon the frother type and concentration and that they are associated with a liquid jet, which initially excites the bubble and then decays to form a surface wave. The addition of the frother did not influence the formation of the jet but did increase its decay rate, hence, dampening the surface wave. It is postulated that the action of the frother is related to an effect on the magnitude of surface tension gradients.

7.
Methods Cell Biol ; 86: 227-40, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18442649

RESUMEN

The mammalian central nervous system is developmentally derived from neuroepithelial cells in the neural plate. These neuroepithelial cells grow and differentiate in response to signals from their surrounding environment. Many of those signals have been well characterized and others remain to be discovered. In cell culture, a conditioned medium, a feeder cell layer, or a tissue extract has been used as supplement in addition to those factors well characterized for maintaining the multipotent status of neural progenitor cells. To date, there have been many types of neural progenitor cells established in culture from various stages of development and from different regions of the nervous system of various species. This chapter will provide a brief introduction to those cultures and a detailed method for culturing rat neural epithelial cells at embryonic stage E9 and characterizing them in vitro and in vivo.


Asunto(s)
Técnicas de Cultivo de Célula , Embrión de Mamíferos/citología , Células Epiteliales/citología , Neuronas/fisiología , Células Madre Pluripotentes/citología , Células Madre/citología , Animales , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Forma de la Célula , Células Cultivadas , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Medio de Cultivo Libre de Suero , Embrión de Mamíferos/fisiología , Células Epiteliales/fisiología , Femenino , Edad Gestacional , Humanos , Neuronas/citología , Células Madre Pluripotentes/fisiología , Embarazo , Ratas , Ratas Sprague-Dawley , Células Madre/fisiología
8.
Cancer Res ; 67(18): 8856-64, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17875727

RESUMEN

RAV12 is a high-affinity immunoglobulin G(1) (IgG(1)) chimeric antibody recognizing an N-linked carbohydrate epitope expressed on a number of human carcinomas and adenocarcinomas. RAV12 is efficacious in treating colon, gastric, and pancreatic tumors in xenograft models in vivo. Insulin-like growth factor-I receptor (IGF-IR) is a protein widely overexpressed in tumor-derived cell lines that promotes cell survival and prevents apoptosis. We found the RAV12 epitope (RAAG12) decorated the IGF-IR proteins of RAV12-responsive cell lines such as COLO201, COLO205, and SNU-16. Here, we report findings of IGF-IR signaling manipulation by RAV12. We found that RAV12 caused a significantly accelerated IGF-I-mediated IGF-IR phosphorylation and desensitization in COLO205. We also observed significant changes in some of the major downstream signaling components of IGF-IR. Data suggested that RAV12 treatment accelerated the desensitization of Akt/PKB through IRS1, and such activation could be attenuated by Tyrphostin AG538 (IGF-IR inhibitor), LY294002, or Wortmannin (phosphoinositide-3-kinase inhibitor). Furthermore, RAV12-inhibited IGF-I stimulated COLO205 growth, and the inhibition could be significantly augmented by mitogen-activated protein kinase inhibitor.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/terapia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Anticuerpos Monoclonales/inmunología , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Neoplasias Colorrectales/inmunología , Células HT29 , Humanos , Inmunoglobulina G/inmunología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación/efectos de los fármacos , Receptor IGF Tipo 1/antagonistas & inhibidores , Transducción de Señal
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