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1.
Sci Data ; 10(1): 384, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322090

RESUMEN

Assessing biomass resource potential is essential for China's ambitious goals of carbon neutrality, rural revitalization, and poverty eradication. To fill the data gap of high spatial resolution biomass resources in China, this study estimates the biomass resource potential for all types of lignocellulosic biomass feedstock at 1 km resolution in 2018, including 9 types of agricultural residues, 11 types of forestry residues, and 5 types of energy crops. By combining the statistical accounting method and the GIS-based method, this study develops a transparent and comprehensive assessment framework, which is in accordance with the principle of food security, forest land and pasture protection, and biodiversity protection. In the end, we organize and store the data in different formats (GeoTIFF, NetCDF, and Excel) for GIS users, integrated modelers, and policymakers. The reliability of this high spatial resolution dataset has been proved by comparing the aggregated data at the subnational and national levels with the existing literature. This dataset has numerous potential uses and is a crucial input to many bioenergy-related studies.


Asunto(s)
Biodiversidad , Bosques , Biomasa , China , Agricultura Forestal/métodos , Reproducibilidad de los Resultados
2.
Chin Neurosurg J ; 9(1): 16, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37231522

RESUMEN

BACKGROUND: Patients with insulo-Sylvian gliomas continue to present with severe morbidity in cognitive functions primarily due to neurosurgeons' lack of familiarity with non-traditional brain networks. We sought to identify the frequency of invasion and proximity of gliomas to portions of these networks. METHODS: We retrospectively analyzed data from 45 patients undergoing glioma surgery centered in the insular lobe. Tumors were categorized based on their proximity and invasiveness of non-traditional cognitive networks and traditionally eloquent structures. Diffusion tensor imaging tractography was completed by creating a personalized brain atlas using Quicktome to determine eloquent and non-eloquent networks in each patient. Additionally, we prospectively collected neuropsychological data on 7 patients to compare tumor-network involvement with change in cognition. Lastly, 2 prospective patients had their surgical plan influenced by network mapping determined by Quicktome. RESULTS: Forty-four of 45 patients demonstrated tumor involvement (< 1 cm proximity or invasion) with components of non-traditional brain networks involved in cognition such as the salience network (SN, 60%) and the central executive network (CEN, 56%). Of the seven prospective patients, all had tumors involved with the SN, CEN (5/7, 71%), and language network (5/7, 71%). The mean scores of MMSE and MOCA before surgery were 18.71 ± 6.94 and 17.29 ± 6.26, respectively. The two cases who received preoperative planning with Quicktome had a postoperative performance that was anticipated. CONCLUSIONS: Non-traditional brain networks involved in cognition are encountered during surgical resection of insulo-Sylvian gliomas. Quicktome can improve the understanding of the presence of these networks and allow for more informed surgical decisions based on patient functional goals.

3.
Brain Behav ; 13(5): e2969, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36978245

RESUMEN

OBJECTIVE: The structural alteration that occurs within the salience network (SN) in patients with insular glioma is unclear. Therefore, we aimed to investigate the changes in the topological network and brain structure alterations within the SN in patients with insular glioma. METHODS: We enrolled 46 patients with left insular glioma, 39 patients with right insular glioma, and 21 demographically matched healthy controls (HCs). We compared the topological network, gray matter (GM) volume, and fractional anisotropy (FA) between HCs and patients after controlling for the effects of age and gender. RESULTS: Patients with insular glioma showed topological network decline mainly in the insula, basal ganglia region, and anterior cingulate cortex (ACC). Compared with HCs, patients primarily showed GM volume increased in the ACC, inferior temporal gyrus (ITG), superior temporal gyrus (STG), temporal pole: middle temporal gyrus (TPOmid), insula, middle temporal gyrus (MTG), middle frontal gyrus, and superior occipital gyrus (SOG), but decreased in TPOmid, ITG, temporal pole: superior temporal gyrus, and SOG. FA declined mainly in the STG, MTG, ACC, superior frontal gyrus, and SOG, and also showed an increased cluster in SOG. CONCLUSIONS: FA represents the integrity of the white matter. In patients with insular glioma, decreased FA may lead to the destruction of the topological network within the SN, which in turn may lead to the decrease of network efficiency and brain function, and the increase of GM volume may compensate for these changes. Overall, this pattern of structural changes provides new insight into the compensation model of insular glioma.


Asunto(s)
Imagen por Resonancia Magnética , Sustancia Blanca , Humanos , Encéfalo , Sustancia Gris/diagnóstico por imagen , Mapeo Encefálico , Sustancia Blanca/diagnóstico por imagen
4.
Small ; 19(11): e2207468, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36564364

RESUMEN

In situ fabrication of macroscale ordered monolayers of nanoparticles (NPs) on targeted substrates is highly desirable for precision electronic and optical devices, while it remains a great challenge. In this study, a solution is provided to address this challenge by developing a colloidal ink formulation and employing the direct-ink-writing (DIW) technique, where on-demand delivery of ink at a targeted location and directional evaporation with controllable rate are leveraged to precisely guide the deposition of polystyrene-grafted gold NPs (Au@PS NPs) into a macroscale monolayer with an ordered Au NP array embedded in a PS thin film. A 2D steady-state diffusion-controlled evaporation model, which explains the parameter dependence of the experimental results and gives semiquantitative agreement with the experimental evaporation kinetics is proposed. The ordered monolayer is used as both nanocrystal floating gates and the tunneling layer for nonvolatile memory devices. It shows significantly enhanced performance compared with a disordered NP film prepared by spin coating. This approach allows for fine control of NP self-assembly to print macroscaleordered monolayers directly onto substrates, which has great promise for application in broad fields, including microelectronic and photoelectronic devices, sensors, and functional coatings.

5.
Environ Sci Technol ; 56(22): 16082-16093, 2022 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-36321829

RESUMEN

Although widely recognized as the key to climate goals, coal "phase down" has long been argued for its side effects on energy security and social development. Retrofitting coal power units with biomass and coal co-firing with a carbon capture and storage approach provides an alternative way to avoid these side effects and make deep carbon dioxide emission cuts or even achieve negative emission. However, there is a lack of clear answers to how much the maximum emission reduction potential this approach can unlock, which is the key information to promote this technology on a large scale. Here, we focus on helping China's 4536 coal power units make differentiated retrofit choices based on unit-level heterogeneity information and resource spatial matching results. We found that China's coal power units have the potential to achieve 0.4 Gt of negative CO2 emission in 2025, and the cumulative negative CO2 emission would reach 10.32 Gt by 2060. To achieve negative CO2 emission, the biomass resource amount should be 1.65 times the existing agricultural and forestry residues, and the biomass and coal co-firing ratio should exceed 70%. Coal power units should grasp their time window; otherwise, the maximum negative potential would decrease at a rate of 0.35 Gt per year.


Asunto(s)
Dióxido de Carbono , Carbón Mineral , Dióxido de Carbono/análisis , Biomasa , Clima , Tecnología , China , Centrales Eléctricas
6.
J Org Chem ; 87(22): 15511-15529, 2022 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-36318193

RESUMEN

We developed a visible-light-mediated [3 + 2] cycloaddition of arylcyclopropylamine with structurally diverse olefins using QXPT-NPh as a highly efficient organic photoredox catalyst. We first achieved the use of various alkyl-substituted alkenes in intermolecular [3 + 2] cycloadditions with cyclopropylamine. We also developed a general and efficient strategy for the construction of structurally diverse cyclopentane-based spiro[4.n] skeletons with 1,3-difunctional groups, which broadly exist in natural products and synthetic molecules. Furthermore, we proposed a hydrogen-bond mode between the arylcyclopropylamine and the photocatalyst QXPT-NPh.


Asunto(s)
Alquenos , Esqueleto , Reacción de Cicloadición , Alquenos/química , Estructura Molecular
7.
Front Neurosci ; 16: 938089, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35873807

RESUMEN

Therapy development for neurodegenerative diseases of the retina constitutes a major unmet medical need, and this may be particularly relevant for inherited diseases of the retina, which are largely untreatable to this day. Therapy development necessitates appropriate models to improve the understanding of the underlying degenerative mechanisms, as well as for the testing and evaluation of novel treatment approaches. This review provides an overview of various in vitro model systems used to study retinal neuroprotection. The in vitro methods and technologies discussed range from primary retinal cell cultures and cell lines, to retinal organoids and organotypic retinal explants, to the cultivation of whole eyeballs. The advantages and disadvantages of these methods are compared and evaluated, also in view of the 3R principles (i.e., the refinement, reduction, and replacement of live animal testing), to identify suitable in vitro alternatives for in vivo experimentation. The article further expands on the use of in vitro models to test and evaluate neuroprotective treatments and to aid the development of retinal drug delivery systems. Among the pharmacological agents tested and characterized in vitro are such that interfere with aberrant cyclic guanosine monophosphate (cGMP) -signaling or such that inhibit the activities of poly (ADP-ribose) polymerase (PARP), histone deacetylases (HDAC), calpain-type proteases, as well as unfolded protein response-related stress. We then introduce nanoparticle-based drug delivery systems and discuss how different in vitro systems may be used to assess their efficacy in the treatment of retinal diseases. The summary provides a brief comparison of available in vitro models and relates their advantages and limitations to the various experimental requirements, for instance, for studies into disease mechanisms, novel treatments, or retinal toxicity. In many cases, combinations of different in vitro models may be required to obtain a comprehensive view of the efficacy of a given retinal neuroprotection approach.

8.
Opt Express ; 29(21): 34427-34440, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34809233

RESUMEN

A large-area mid-infrared broadband absorber is proposed in this paper. The absorber is a spiral ITO structure grown on a hexagonal lattice arrangement of silicon nanopillars by using a glancing angle deposition method. The experimental results show that when the heights of the silicon nanopillars are 1.7 µm and the number of rotation depositions is n = 5, that is, the rotation angle is 150 degrees, the absorber absorbs more than 81% of electromagnetic waves in the 2.5-6 µm spectral range. In the atmospheric window of 3-5 µm, the integral absorption reaches 96%. The experimental results also show that the absorbing ability of the ITO structure in the mid-infrared atmospheric window is significantly stronger than that of the structure composed of silver under the same preparation conditions. The main reasons for the broadband absorption are that the spiral ITO structure has resonant absorption of electromagnetic waves with different wavelengths in the empty cavity regions with different sizes, and ITO has longer penetration depths than noble metals in the mid-infrared band, which brings about stronger broadband absorption. The combination of the two leads to a broadening of the total absorption spectrum. The higher heights of the silicon nanopillars enhance absorption further. Additionally, the loose spiral ITO distributions indicate lower mean plasma concentration and then increase penetration depths further, resulting in stronger light absorption. Such a large-area mid-infrared absorption structure with a simple preparation method has potential applications in mid-infrared cloaking and sensing.

9.
Biomolecules ; 11(10)2021 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-34680161

RESUMEN

Rhodopsin (RHO) misfolding mutations are a common cause of the blinding disease autosomal dominant retinitis pigmentosa (adRP). The most prevalent mutation, RHOP23H, results in its misfolding and retention in the endoplasmic reticulum (ER). Under homeostatic conditions, misfolded proteins are selectively identified, retained at the ER, and cleared via ER-associated degradation (ERAD). Overload of these degradation processes for a prolonged period leads to imbalanced proteostasis and may eventually result in cell death. ERAD of misfolded proteins, such as RHOP23H, includes the subsequent steps of protein recognition, targeting for ERAD, retrotranslocation, and proteasomal degradation. In the present study, we investigated and compared pharmacological modulation of ERAD at these four different major steps. We show that inhibition of the VCP/proteasome activity favors cell survival and suppresses P23H-mediated retinal degeneration in RHOP23H rat retinal explants. We suggest targeting this activity as a therapeutic approach for patients with currently untreatable adRP.


Asunto(s)
Retículo Endoplásmico/efectos de los fármacos , Degeneración Retiniana/genética , Retinitis Pigmentosa/genética , Rodopsina/genética , Alcaloides/farmacología , Animales , Animales Modificados Genéticamente , Benzoquinonas/farmacología , Modelos Animales de Enfermedad , Retículo Endoplásmico/genética , Humanos , Lactamas Macrocíclicas/farmacología , Mutación/genética , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/patología , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/genética , Pliegue de Proteína/efectos de los fármacos , Proteolisis/efectos de los fármacos , Ratas , Retina/efectos de los fármacos , Retina/crecimiento & desarrollo , Retina/patología , Degeneración Retiniana/patología , Retinitis Pigmentosa/patología , Rodopsina/ultraestructura
10.
ISA Trans ; 110: 258-270, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33121733

RESUMEN

In this paper, for periodic motion tasks, combining adaptive PID-type sliding mode control (APIDSMC), model reference adaptive control (MRAC) and periodic adaptive learning control (PALC), a novel APIDSMC-PALC compensation approach towards energy efficiency is proposed to suppress the influence of torque ripple in permanent magnet synchronous motor (PMSM) servo systems. Using particle swarm optimization (PSO) algorithm, the equivalent control gain of sliding mode control is optimized to achieve energy efficiency during long-term operation. The objective of the proposed ripple compensation algorithm is to accurately approximate two dominant harmonic amplitudes in the torque ripple and generate an additional control effort for ripple compensation. Simulation and testbed experimental results demonstrate that with the proposed ripple compensation algorithm, the objective of excellent position tracking performance is ensured, and the energy efficiency is improved.

11.
Front Oncol ; 10: 1186, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32775302

RESUMEN

Objective: Identification of tumor invasiveness of pulmonary adenocarcinomas before surgery is one of the most important guides to surgical planning. Additionally, preoperative diagnosis of lung adenocarcinoma with micropapillary patterns is also critical for clinical decision making. We aimed to evaluate the accuracy of deep learning models on classifying invasiveness degree and attempted to predict the micropapillary pattern in lung adenocarcinoma. Methods: The records of 291 histopathologically confirmed lung adenocarcinoma patients were retrospectively analyzed and consisted of 61 adenocarcinoma in situ, 80 minimally invasive adenocarcinoma, 117 invasive adenocarcinoma, and 33 invasive adenocarcinoma with micropapillary components (>5%). We constructed two diagnostic models, the Lung-DL model and the Dense model, based on the LeNet and the DenseNet architecture, respectively. Results: For distinguishing the nodule invasiveness degree, the area under the curve (AUC) value of the diagnosis with the Lung-DL model is 0.88 and that with the Dense model is 0.86. In the prediction of the micropapillary pattern, overall accuracies of 92 and 72.91% were obtained for the Lung-DL model and the Dense model, respectively. Conclusion: Deep learning was successfully used for the invasiveness classification of pulmonary adenocarcinomas. This is also the first time that deep learning techniques have been used to predict micropapillary patterns. Both tasks can increase efficiency and assist in the creation of precise individualized treatment plans.

12.
Int J Med Sci ; 17(5): 591-598, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32210708

RESUMEN

Diabetic retinopathy (DR) is the common and important cause for visual impairment and blindness in working-aged people. Microangiopathy and inflammatory reactions are the key components of DR. Recently, long non-coding RNA myocardial infarction-associated transcript (MIAT) has emerged as a vital player in regulation for inflammatory processes and microvascular dysfunction. Additionally, cell-based therapy provides a potential option for the treatment of DR. The anti-inflammatory effects and repair therapy of mesenchymal stem cells (MSCs) have been paid more attention. This study investigated the effects of human umbilical-cord mesenchymal stem cells (HUMSCs) injection on diabetic rat model. The results show that the level of MIAT is significantly decreased in the diabetic retina after the injection of HUMSCs. Moreover, HUMSCs can significantly decrease the expression of IL-1ß and IL-6 mRNA; alleviate microvascular permeability, and upregulate Occludin expression. Studies have shown that MIAT knockdown could alleviate diabetes-induced inflammation responses and vascular leakage. Furthermore, our findings also showed that the expression of MIAT was positively correlated with the expression of IL-1ß and IL-6. These results suggest that MIAT might play important regulatory roles in alleviating inflammatory reactions and microangiopathy inducing by DR after transplantation of HUMSCs.


Asunto(s)
Retinopatía Diabética/terapia , Trasplante de Células Madre Mesenquimatosas , ARN Largo no Codificante/metabolismo , Retina/metabolismo , Animales , Permeabilidad Capilar , Diabetes Mellitus Experimental , Retinopatía Diabética/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Ocludina/metabolismo , Distribución Aleatoria , Ratas Sprague-Dawley
13.
Pituitary ; 23(3): 246-252, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32062801

RESUMEN

PURPOSE: This study was designed to develop a computer-aided diagnosis (CAD) system based on a convolutional neural network (CNN) to diagnose patients with pituitary tumors. METHODS: We included adult patients clinically diagnosed with pituitary adenoma (pituitary adenoma group), or adult individuals without pituitary adenoma (control group). After pre-processing, all the MRI data were randomly divided into training or testing datasets in a ratio of 8:2 to create or evaluate the CNN model. Multiple CNNs with the same structure were applied for different types of MR images respectively, and a comprehensive diagnosis was performed based on the classification results of different types of MR images using an equal-weighted majority voting strategy. Finally, we assessed the diagnostic performance of the CAD system by accuracy, sensitivity, specificity, positive predictive value, and F1 score. RESULTS: We enrolled 149 participants with 796 MR images and adopted the data augmentation technology to create 7960 new images. The proposed CAD method showed remarkable diagnostic performance with an overall accuracy of 91.02%, sensitivity of 92.27%, specificity of 75.70%, positive predictive value of 93.45%, and F1-score of 92.67% in separate MRI type. In the comprehensive diagnosis, the CAD achieved better performance with accuracy, sensitivity, and specificity of 96.97%, 94.44%, and 100%, respectively. CONCLUSION: The CAD system could accurately diagnose patients with pituitary tumors based on MR images. Further, we will improve this CAD system by augmenting the amount of dataset and evaluate its performance by external dataset.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/diagnóstico , Inteligencia Artificial , Humanos , Redes Neurales de la Computación
14.
Opt Express ; 27(23): 33243-33250, 2019 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-31878397

RESUMEN

This paper proposes a mid-infrared chiral structure, which consists of L-shaped indium tin oxide (ITO) films formed on self-assembled monolayer polystyrene microspheres in two orthogonal directions by oblique angle deposition technique. Experimental results demonstrate that the structure exhibit circular dichroism (CD) responses in the range of 2.5 - 4 µm. As the thickness difference of the ITO films in the two orthogonal directions increases, the CD response enhances. The reason is that the ITO films produce cross dipoles and their bigger differences in thickness bring to bigger phase differences in optical chirality. The experimental results also demonstrate that the CD signals are evidently stronger than those of the structure consisting of silver in the mid-infrared band. This work provides a new idea for the fabrication of mid-infrared chiral structures, which have potential applications in the polarization state control of mid-infrared lasers.

15.
Int J Clin Exp Pathol ; 10(8): 8174-8186, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31966669

RESUMEN

Vascular endothelial growth factor (VEGF) is the typical representative factor of diabetic retinopathy (DR) and is considered to be a key inducer of retinal vascular permeability in DR. Anti-VEGF has been widely used in clinical treatment but every patient is effective, therefore, it is necessary to find other effective factors that participate in the pathology of DR. We provide evidence from both human and animal experiments for the considerable roles of classical neuronal guidance factors, netrin-1 and netrin-4, in indicating and amending the pathology of DR. We reveal that levels of both netrin-1 and netrin-4 are reduced while VEGF increases in DR patients and animal models. We demonstrate through different experimental methods that augmenting netrin-1 and netrin-4 can alleviate vasculopathy and neuropathy which appear in DR. Our findings offer additional effect targets besides VEGF for DR and suggest we should increase the focus on neurovascular crosstalk as DR is a neurovascular disease.

16.
Opt Express ; 19(26): B229-34, 2011 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-22274023

RESUMEN

A centralized optical processing unit (COPU) that functions both as a wavelength converter (WC) and optical burst equaliser in a 10 Gb/s wavelength-converting optical access network is proposed and experimentally characterized. This COPU is designed to consolidate drifting wavelengths generated with an uncooled laser in the upstream direction into a stable wavelength channel for WDM backhaul transmission and to equalize the optical loud/soft burst power in order to relax the burst-mode receiver dynamic range requirement. The COPU consists of an optical power equaliser composed of two cascaded SOAs followed by a WC. Using an optical packet generator and a DC-coupled PIN-based digital burst-mode receiver, the COPU is characterized in terms of payload-BER for back-to-back and backhaul transmission distances of 22, 40, and 62 km. We show that there is a compromise between the receiver sensitivity and overload points that can be optimized tuning the WC operating point for a particular backhaul fiber transmission distance. Using the optimized settings, sensitivities of -30.94, -30.17, and -27.26 dBm with overloads of -9.3, -5, and >-5 dBm were demonstrated for backhaul transmission distances of 22, 40 and 62 km, respectively.

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