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1.
Eur J Immunol ; 53(4): e2250100, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36648433

RESUMEN

Autoimmune hepatitis (AIH) eventually progresses to liver fibrosis, cirrhosis, and even hepatocellular carcinoma, causing irreversible damage to the liver. Concanavalin A-induced hepatitis in mice is a well-established model with pathophysiology similar to that of immune-mediated liver injury in human viral and autoimmune hepatitis, and it has been widely used to explore the pathogenesis and clinical treatment of human immune hepatitis. Artemisinin has been shown to exhibit anti-inflammatory effects through unclear mechanisms. In this study, we aimed to assess the effect of the artemisinin derivative TPN10466 on AIH. In vitro studies showed that TPN10466 dose dependently inhibited the percentage of IFN-γ-producing T cells. Further studies showed that TPN10466 attenuated the disease severity of AIH by downregulating the ability of lymphocytes to secrete IFN-γ and by reducing lymphocyte number in the liver. In addition, we found that TPN10466 treatment reduced T-cell responses by inhibiting JNK, ERK, and p38 pathways. In conclusion, our work suggests that TPN10466 provides protection against the autoimmune disease AIH by suppressing the inflammatory response of T cells, suggesting that TPN10466 may be a promising potential agent for the treatment of AIH.


Asunto(s)
Artemisininas , Hepatitis Autoinmune , Animales , Humanos , Ratones , Artemisininas/metabolismo , Artemisininas/farmacología , Artemisininas/uso terapéutico , Concanavalina A/metabolismo , Concanavalina A/farmacología , Concanavalina A/uso terapéutico , Hepatitis Autoinmune/tratamiento farmacológico , Hígado/patología , Sistema de Señalización de MAP Quinasas
2.
J Immunol ; 208(7): 1545-1553, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35277421

RESUMEN

Multiple sclerosis (MS) is a chronic inflammatory demyelinating autoimmune disease with chronic inflammatory demyelination of the CNS. Experimental autoimmune encephalomyelitis (EAE) is an important animal model to study MS, with many pathological phenomena similar to MS. Th17 cells are important regulators of EAE and MS pathogenesis. Most cytokines needed for Th cell development are secreted by APCs, such as dendritic cells (DCs). Consequently, MS could be improved by inhibiting cytokine secretion from DCs. In this study, we reported that chlorzoxazone could ameliorate EAE pathogenesis via inhibiting IL-6 production by DCs. The EAE signs in the chlorzoxazone-treated group of mice were relieved, which was mainly manifested as lower clinical scores, a decrease in the number of immune cells, and a reduction of demyelination in the CNS. Moreover, the proportion of Th17 cells in the spleen and CNS decreased significantly. In vitro experiments showed that chlorzoxazone treatment significantly reduced DC-derived IL-6 production. In the DC-T cell coculture experiment, significantly decreased Th17 differentiation was observed after chlorzoxazone treatment. In addition, mass spectrometric analysis was performed to elucidate the mechanism by which chlorzoxazone affected EAE and DC function. We showed that the effect of chlorzoxazone on inhibiting the secretion of IL-6 by DCs may be mediated via the AMP-activated protein kinase pathway. Overall, our study elucidated the key role of chlorzoxazone in regulating EAE pathogenesis and suggested that it might be used as a new drug for MS patients.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Animales , Clorzoxazona/metabolismo , Clorzoxazona/farmacología , Células Dendríticas , Humanos , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos C57BL , Células Th17
3.
Opt Express ; 31(20): 33003-33014, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37859089

RESUMEN

A simultaneous magnetic field and temperature sensing scheme based on cascaded microwave photonic filters (MPFs) with high resolution is proposed and experimentally demonstrated. A polarization maintaining fiber bonded with a giant magnetostrictive material acts both as a magnetic field sensing probe and an important unit of a dispersion-induced MPF. A 500 m single mode fiber in a two-tap MPF is used to perform temperature compensation. The power fading frequency of the dispersion-induced MPF and the dip frequency of the two-tap MPF are selected to monitor the magnetic field and temperature changes. When temperature changes, both power fading frequency and dip frequency will change. While only power fading frequency shifts as magnetic field changes. Consequently, dual parameter sensing can be achieved by monitoring the characteristic microwave frequencies of the two MPFs. The temperature cross-sensitivity is well resolved in this way. In the experiment, the microwave frequency changes 5.84 MHz as external magnetic field increases by 1 mT. The corresponded theoretical resolution can reach 0.17 nT, which is only limited by the minimum resolution of vector network analyzer.

4.
Opt Lett ; 48(8): 2122-2125, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37058657

RESUMEN

An optical amplification-free deep reservoir computing (RC)-assisted high-baudrate intensity modulation direct detection (IM/DD) system is experimentally demonstrated using a 100G externally modulated laser operated in C-band. We transmit 112 Gbaud 4-level pulse amplitude modulation (PAM4) and 100 Gbaud 6-level PAM (PAM6) signals over a 200-m single-mode fiber (SMF) link without any optical amplification. The decision feedback equalizer (DFE), shallow RC, and deep RC are adopted in the IM/DD system to mitigate impairment and improve transmission performance. Both PAM transmissions over a 200-m SMF with bit error rate (BER) performance below 6.25% overhead hard-decision forward error correction (HD-FEC) threshold are achieved. In addition, the BER of the PAM4 signal is below the KP4-FEC limit after 200-m SMF transmission enabled by the RC schemes. Thanks to the use of a multiple-layer structure, the number of weights in deep RC has been reduced by approximately 50% compared with the shallow RC, whereas the performance is comparable. We believe that the optical amplification-free deep RC-assisted high-baudrate link has a promising application in intra-data center communications.

5.
J Environ Manage ; 331: 117215, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36646038

RESUMEN

The temporal and spatial patterns of wind power installation and the evaluation of carbon emission reduction potentials are of great significance to promoting China's wind power development planning and dual carbon targets achievement. This study analyzes the temporal and spatial characteristics, identifies main driving factors, and measures carbon emission reduction potentials of China's wind power installation by province based on spatial autocorrelation analysis and spatial econometric model. Overall, China's wind power installed capacity increased rapidly from 346 MW in 2000 to 279,550 MW in 2020, basically showing a significant positive spatial correlation during 2000 and 2020. Regarding driving factors of wind power installation, the technological factors and environmental factors were the main positive factors for wind power installation, and the economic factors and resource endowments showed positive spatial spillover effects. Regarding carbon emission reduction potentials, the carbon emission reduction potentials of China's wind power installation increased by year, among which Northwest China gradually accelerated Northeast China after 2015. Based on China's wind power evolution characteristics and carbon emission reduction potentials, this study attempts to provide quantitative supports and policy implications to promote sustainable development of wind power industry and the achievement of carbon peak and carbon neutrality within China.


Asunto(s)
Carbono , Viento , Carbono/análisis , Tecnología , Análisis Espacial , China , Dióxido de Carbono/análisis , Desarrollo Económico
6.
Cell Immunol ; 373: 104500, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35276582

RESUMEN

Multiple sclerosis (MS) was one of the major conditions causing neurological dysfunction and was an incurable progressive central nervous system disease. Experimental autoimmune encephalomyelitis (EAE) was the most commonly used experimental model of MS. Artemisinin have been shown to exhibit anti-inflammatory effects through unclear mechanisms. In this study, we aimed to evaluate the effect of administration of the artemisinin derivative TPN10466 in EAE. TPN10466 alleviated the severity of disease in EAE. Further studies showed that TPN10466 inhibited lymphocyte migration by downregulating chemokine expression and adhesion molecules. In addition, studies showed that TPN10466 directly inhibited Th1 and Th17 differentiation and reduced Th1 and Th17 infiltration into the central nervous system. In conclusion, our work demonstrated that TPN10466 provided protection against the autoimmune disease EAE by inhibiting the migration of immune cells and suppressing Th1/Th17 differentiation, suggesting that TPN10466 could be a potential for promising potential agent for the treatment of MS/EAE.


Asunto(s)
Artemisininas , Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Animales , Artemisininas/metabolismo , Artemisininas/farmacología , Artemisininas/uso terapéutico , Diferenciación Celular , Movimiento Celular , Ratones , Ratones Endogámicos C57BL , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/metabolismo , Índice de Severidad de la Enfermedad , Células TH1 , Células Th17
7.
Opt Express ; 30(26): 47515-47527, 2022 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-36558679

RESUMEN

An approach for simultaneous modulation format identification (MFI) and optical signal-to-noise ratio (OSNR) monitoring in digital coherent optical communications is proposed based on optoelectronic reservoir computing (RC) and the signal's amplitude histograms (AHs) obtained after the adaptive post-equalization. The optoelectronic RC is implemented using a Mach-Zehnder modulator and optoelectronic delay feedback loop. We investigate the performance of the proposed model with the number of symbols, bins of AHs and the hyperparameters of optoelectronic RC. The results show that 100% MFI accuracy can be achieved simultaneously with accurate OSNR estimation for different modulation formats under study. The lowest achievable OSNR estimation mean absolute errors for the dual-polarization (DP)-quadrature phase-shift keying signal, the DP-16-ary quadrature amplitude modulation (16QAM) signal, and the DP-64QAM signal are 0.2 dB, 0.32 dB and 0.53 dB, respectively. The robustness of the proposed scheme is also evaluated when the optoelectronic RC is in presence of additive white Gaussian noises. Then, a proof of concept experiment is demonstrated to further verify our proposed method. The proposed approach offers a potential solution for next-generation intelligent optical performance monitoring in the physical layer.

8.
Int J Med Sci ; 19(1): 13-24, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34975295

RESUMEN

Retinal ischemia-reperfusion injury (RIRI) is of common occurrence in retinal and optic nerve diseases. The BDNF/TrkB signaling pathway has been examined to be neuroprotective in RIRI. In this study, we investigated the role of a potent selective TrkB agonist 7,8-dihydroxyfavone (DHF) in rat retinas with RIRI. Our results showed that RIRI inhibited the conversion of BDNF precursor (proBDNF) to mature BDNF (mBDNF) and increased the level of neuronal cell apoptosis. Compared with RIRI, DHF+RIRI reduced proBDNF level and at the same time increased mBDNF level. Moreover, DHF administration effectively activated TrkB signaling and and downstream Akt and Erk signaling pathways which increased nerve cell survival. The combined effects of mBDNF/proBDNF increase and TrkB signaling activation lead to reduction of apoptosis level and protection of retinas with RIRI. Moreover, it was also found that astrocytes labeled by GFAP were activated in RIRI and NF-kB mediated the increased expressions of inflammatory factors and these effects were partially reversed by DHF administration. Besides, we also used RNA sequencing to analyze the differently expressed genes (DEGs) and their enriched (Kyoto Encyclopedia of Genes and Genomes) KEGG pathways between Sham, RIRI, and DHF+RIRI. It was found that 1543 DEGs were differently expressed in RIRI and 619 DEGs were reversed in DHF+RIRI. The reversed DEGs were typically enriched in PI3K-Akt signaling pathway, Jak-STAT signaling pathway, NF-kB signaling pathway, and Apoptosis. To sum up, the DHF administration alleviated apoptosis and inflammation induced by RIRI via activating TrkB signaling pathway and may serve as a promising drug candidate for RIRI related ophthalmopathy.


Asunto(s)
Apoptosis/efectos de los fármacos , Flavanonas/farmacología , Inflamación/prevención & control , Glicoproteínas de Membrana/metabolismo , FN-kappa B/metabolismo , Fármacos Neuroprotectores/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor trkB/metabolismo , Daño por Reperfusión/fisiopatología , Retina/fisiopatología , Animales , Modelos Animales de Enfermedad , Masculino , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Transducción de Señal
9.
Appl Opt ; 61(12): 3473-3479, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35471444

RESUMEN

Time-delayed reservoir computing (RC) is a brain inspired paradigm for processing temporal information, with simplification in the network's architecture using virtual nodes embedded in a temporal delay line. In this work, a novel, to the best of our knowledge, RC system based on a dual-loop optoelectronic oscillator is proposed to enhance the prediction and classification. The hardware is compact and easy to implement, and only a section of fiber compared to the traditional optoelectronic oscillator reservoir is added to conform the dual-loop scheme. Compared with the traditional reservoir, a remarkable performance of the proposed RC system is demonstrated by simulation on three well-known tasks, namely the nonlinear auto regressive moving average (NARMA10) task, signal waveform recognized task, and handwritten numeral recognition. The parameter optimization in the NARMA10 task is presented with influenced factors. The novel RC system finally obtains a normalized mean square error at 0.0493±0.007 in NARMA10 task, 6.172×10-6 in signal waveform recognized task, and a word error rate at 9% in handwritten numeral recognition with suitable parameters.


Asunto(s)
Redes Neurales de la Computación , Semiconductores , Simulación por Computador
10.
Bioprocess Biosyst Eng ; 45(12): 1955-1966, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36355205

RESUMEN

In this study, an amino-functionalized ionic liquid-modified magnetic chitosan (MACS-NIL) containing 2,2-diamine-di-3-ethylbenzothiazolin-6-sulfonic acid (ABTS) was used as a carrier, and dialdehyde starch (DAS) was used as a cross-linking agent to covalently immobilize laccase (MACS-NIL-DAS-lac), which realized the co-immobilization of laccase and ABTS. The carrier was characterized by Fourier infrared transform spectroscopy, scanning electron microscopy, thermogravimetric analysis, X-ray diffraction analysis, electron paramagnetic resonance, etc. The immobilization efficiency and activity retention of MACS-NIL-DAS-lac could reach 76.7% and 69.8%, respectively. At the same time, its pH stability, thermal stability, and storage stability had been significantly improved. In the organic pollutant removal performance test, the removal rate of 2,4-dichlorophenol (10 mg/L) by MACS-NIL-DAS-lac (1 U) could reach 100% within 6 h, and the removal efficiency could still reach 88.6% after six catalytic runs. In addition, MACS-NIL-DAS-lac also showed excellent degradation ability for other conventional phenolic pollutants and polycyclic aromatic hydrocarbons. The research results showed that MACS-NIL-DAS fabricated by the combination inorganic material, organic biomacromolecules, ionic liquid, and electron mediator could be used as a novel carrier for laccase immobilization and the immobilized laccase showed excellent removal efficiency for organic pollutants.


Asunto(s)
Quitosano , Contaminantes Ambientales , Líquidos Iónicos , Nanoestructuras , Quitosano/química , Electrones , Enzimas Inmovilizadas/química , Lacasa/química
11.
J Environ Manage ; 312: 114854, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35325737

RESUMEN

With the rapid population growth and economic development, the necessity to explore energy-saving potentials in typical seawater desalination project is increasingly essential. Taking the Reverse Osmosis (RO) seawater desalination project in Hebei Province, China as a case, this study performed systematic accounting framework combining the direct and indirect energy consumption from the energy-water nexus perspective, and carried out the energy-saving potential assessment and systematical optimization configuration. From the results, the total direct energy consumption of the project was 2.23 × 106 kWh, and the total embodied energy consumption was 2.18 × 107 kWh. Define the embodied energy consumption (ESE) as an evaluation index of energy saving potentials, the energy consumption degree before optimization is 79.54%, which could be reduced to 26.30% after optimization. The results showed that the systematic accounting framework in this study can greatly improve the accuracy of energy consumption measurement in the project, and the systematical optimization configuration can significantly reduce energy consumption and improve the energy-saving design under the minimum investment in the seawater desalination projects.


Asunto(s)
Purificación del Agua , Agua , Filtración , Ósmosis , Agua de Mar , Purificación del Agua/métodos
12.
Opt Express ; 29(24): 38989-39000, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809271

RESUMEN

An optoelectronic oscillator (OEO)-based fiber optic current sensor (FOCS) with greatly improved sensitivity is proposed and experimentally demonstrated. A microwave photonic filter (MPF) induced by the dispersion effect of a linearly chirped fiber Bragg grating (LCFBG) is used to select the frequency of the OEO oscillating signal. A two-tap MPF formed by a polarization multiplexed composite cavity is cascaded to achieve a stable single mode oscillation. When the current changes, the magneto-optic phase shift induced by Faraday effect will be introduced between the left and right circularly polarized lights transmitted in the reflective sensing unit. The magneto-optic phase shift is converted to the phase difference between the optical carrier and sidebands through a LiNbO3 Mach-Zehnder modulator. This phase difference is the decisive factor for the center frequency of the cascaded MPF as well as the oscillating frequency. Therefore, the current can be measured in the microwave frequency domain, which can improve the interrogation speed and accuracy to a large extent. The experimental results show that the oscillating frequency shifts up to 407.9 MHz as the current increases by 1 A.

13.
Opt Lett ; 46(15): 3753-3756, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34329273

RESUMEN

This Letter presents a novel, to the best of our knowledge, linearized analog photonic link (APL) based on a phase-coherent orthogonal light wave generator that consists of a polarization-dependent Mach-Zehnder modulator (MZM) and a polarization controller (PC). By adjusting the PC and bias voltage of MZM, the third-order intermodulation (IMD3) terms can be suppressed while retaining a high gain for the fundamental terms, which indicates that the spurious free dynamic range (SFDR) of the proposed APL can be much improved. To further verify the feasibility of the proposed APL, a proof-of-concept experiment is performed, and the performances are compared with conventional APL. The experimental results demonstrate that a 14 dB improvement in the fundamental to IMD3 power ratio and an SFDR of 100.2dB⋅Hz2/3 or 119.1dB⋅Hz2/3 for a noise floor of -139dBm/Hz or -163.9dBm/Hz are achieved. In addition, an orthogonal frequency division multiplexing signal with 30 MHz bandwidth centered at 2.5 GHz is delivered by our proposed APL, whose signal-to-noise ratio is increased by 10 dB, compared to conventional APL.

14.
Appl Opt ; 60(27): 8579-8587, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34612961

RESUMEN

A multiband radio-over-fiber system for a fifth-generation (5G) mobile communication technology mobile fronthaul network is proposed, which can transmit radio frequency (RF) signals in four different frequency bands of 700 MHz, 1.8 GHz, 3.5 GHz, and 26 GHz with different data rates simultaneously. The proposed system can satisfy the multiscenario demand of 5G and realize 4G/5G coexistence. A dual-polarization binary phase-shift keying modulator is utilized to alleviate the interference between multiple-frequency bands. The system is analyzed theoretically and verified through simulation. The variations of error vector magnitudes (EVMs) of four transmitted RF signals in function of the received optical power (ROP) are investigated. The simulation results show that the system has good performance after 10 km standard single-mode fiber (SMMF) transmission. When the ROP is above -3.3dBm, the EVM of the system conforms to the 3GPP specification. The power penalty of the system is within 1.9 dB at the 3GPP EVM performance specification after transmitting over a 10 km SSMF.

15.
J Environ Manage ; 280: 111741, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33352380

RESUMEN

Land occupation by solar power installations has become a rising concern that may cause adverse impacts on natural ecosystems and biodiversity. Existing studies mainly adopt a local perspective to view land use requirements of solar power and forget that the solar-based electricity system is subordinate to the macro economy and nourished by the material, machinery and service support by various economic sectors. To manifest a key aspect of the footprint of solar power on land resources, this study uncovered the extensive industrial land use initiated by the infrastructure of a representative pilot solar-based electricity plant using a systems perspective. The results in this study show that in magnitude, land footprint by the infrastructure of the pilot solar plant amounts to three times as much as the onsite land area. Also, the land footprint calculated is revealed as one order of magnitude larger than a previous finding that includes primary materials only, and four to seven times higher than the onsite land use by coal-based electricity plants. The outcome implies that existing environmental management policies need to be re-evaluated by putting enough emphasis on the land displacement by solar power systems along the production chain.


Asunto(s)
Energía Solar , China , Ecosistema , Política Ambiental , Luz Solar
16.
Opt Lett ; 45(16): 4519-4522, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32796998

RESUMEN

A novel, to the best of our knowledge, interrogation scheme based on an optoelectronic oscillator (OEO) with high sensitivity and high speed response for a fiber optical current sensor utilizing a reflective interferometer is proposed and experimentally demonstrated. Due to the Faraday effect, a magneto-optic phase shift induced by current variation is generated between two orthogonal light waves. The polarization-dependent properties of the Mach-Zehnder modulator are used to convert the magneto-optic phase shift into the phase difference between the optical carrier and sideband, which is then mapped to the oscillating frequency shift by closing an OEO loop. A high current sensitivity of 152.5 kHz/A with a range of 0-2.5 A is obtained in the experiment.

17.
J Environ Manage ; 262: 110250, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32090880

RESUMEN

Given the aim of maintaining global warming below 2 °C, carbon emission reduction has become a global top priority. Since the Belt and Road Initiative has increasing influence on manufacturing-oriented developing countries, more attention should be paid to carbon emission reduction in these regions. This study conducts a comprehensive analysis by analyzing the carbon inequality and regional development and compares the carbon emissions driven by final demand among countries in and outside the Belt and Road area from 1990 to 2015. It is found that the majority of the Belt and Road regions achieved a rapid GDP growth rate with increasing carbon emissions, in which the investment-driven type demonstrated a significant growth. In contrast, the developed countries outside the Belt and Road area maintained their economic growth while decreasing the carbon emissions owed to the declining of investment-driven emissions; however the consumption-driven emissions stably remained a relatively high level. Our results showed that the inequality of carbon emission within Belt and Road regions is lower than the global average, while the inequality of the investment-driven emissions showed an obviously increasing trend. By discussing the carbon inequality and regional development, rational and feasible strategies for countries and regions within and outside the Belt and Road area are essential, and different types of strategies such as low-carbon technologies transfers and overseas financial cooperation are suggested for regional carbon emission reduction and sustainable regional development under the Belt and Road Initiative.


Asunto(s)
Carbono , Desarrollo Económico , Dióxido de Carbono , China , Calentamiento Global , Factores Socioeconómicos
18.
J Environ Manage ; 268: 110701, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32510436

RESUMEN

Reducing fossil fuel consumption is a top priority option for climate change mitigation, which requires collaborations of partners along the supply chain, such as energy suppliers, energy consumers and final consumers of goods and services. A comprehensive analysis of fossil fuel consumption is useful for policymakers to reduce demand but still absent. This study explores the national contribution to global energy consumption from different perspectives in the global supply chain and is designed to complement current energy reduction policies. For the developed countries, energy consumptions are stable from 2000 to 2014, while that of emerging countries almost doubled (e.g., China and India). Most of the developing countries are producers whose production-based and final production-based energy consumptions are higher than their consumption-based ones, except India after the global financial crisis. In contrast, the developed countries are consumers, whose consumption-based energy consumptions are higher. At the sectoral level, the service sector is the largest contributor to consumption- and income-based energy consumption. The analysis in this study can create opportunities for all the parties alongside the supply chain in reducing fossil fuel consumption.


Asunto(s)
Combustibles Fósiles , Renta , China , India , Factores Socioeconómicos
19.
J Environ Manage ; 263: 110332, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32883471

RESUMEN

The carbon-emission transfer between two representative developing economies - China and Africa - behind the international trade has aroused quite a few controversies, which have not been fully estimated and understood yet. In this paper, the Multiregional Input-Output (MRIO) method is applied to the participants of Forum on China-Africa Cooperation (FOCAC) from the global perspective to reveal the roles both China and Africa have played in the global supply chain as either the original emitter or the final consumer, and to depict the evolution pattern of carbon transfer via Sino-Africa trade from the year 2000-2015. The findings are as follows: 1) China has played the role of net exporter of embodied carbon-emission in Sino-Africa trade, for the amount of emitted carbon China had born yet resulted by consumption in Africa well surpassed that vice versa. 2) Compared to the carbon-emission flows embodied in EU-Africa and US-Africa trades, China has shouldered more carbon-emission derived from Africa's consumption. 3) The sectoral contribution and intensities of embodied carbon-emission correspond to the trading pattern between China and Africa, which stems from the two parties' comparative advantages and economic complementarity. 4) The intensities of embodied carbon-emission on both sides are declining towards a rosy prospect, which indicates an improving carbon-emission efficiency of both economies. From a global perspective, both China and Africa play a positive part in carbon-emission reduction. The results in this study can facilitate low-carbon and high-efficiency trading link between the two economies.


Asunto(s)
Comercio , Internacionalidad , África , Carbono , China
20.
Biotechnol Lett ; 41(12): 1439-1449, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31659576

RESUMEN

OBJECTIVE: To enhance ergot alkaloid production of Claviceps purpurea Cp-1 strain by epigenetic modification approach. RESULTS: The chemical epigenetic modifiers were screened to promote ergot alkaloid production of the Cp-1 strain. The histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) was found to significantly enhance the alkaloid productivity of the strain. Particularly, the titers of total ergot alkaloids were gradually increased with the increase of SAHA concentration in the fermentation medium, and the highest production of ergot alkaloids could be achieved at the concentration of 500 µM SAHA. Specially, the titers of ergometrine and total ergot alkaloids were as high as 95.4 mg/L and 179.7 mg/L, respectively, which were twice of those of the control. Furthermore, the mRNA expression levels of the most functional genes in the ergot alkaloid synthesis (EAS) gene cluster were up-regulated under SAHA treatment. It was proposed that SAHA might increase histone acetylation in the EAS gene cluster region in the chromosome, which would loosen the chromosome structure, and subsequently up-regulate the mRNA expression levels of genes involved in the biosynthesis of ergot alkaloids, thereby resulting in the markedly increase in the production of ergot alkaloids. CONCLUSIONS: The ergot alkaloid production by the C. purpurea Cp-1 strain can be effectively increased by the application of histone deacetylase inhibitor. Our work provides a reference for using the chemical epigenetic modifiers to improve SM production in other fungi.


Asunto(s)
Vías Biosintéticas/genética , Claviceps/genética , Claviceps/metabolismo , Epigénesis Genética , Alcaloides de Claviceps/biosíntesis , Vías Biosintéticas/efectos de los fármacos , Claviceps/efectos de los fármacos , Fermentación , Inhibidores de Histona Desacetilasas/metabolismo
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