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Ulcerative colitis (UC) is difficult to cure and easy to relapse, leading to poor quality of life for patients. Oxymatrine (OMT) is one of the main alkaloids of Sophora flavescens Aiton, which has many effects, such as anti-inflammation, anti-oxidative stress, and immunosuppression. This study aimed to investigate whether OMT could attenuate ulcerative colitis by inhibiting the NOD-like receptor family pyrin domain containing three (NLRP3) inflammasome-mediated pyroptosis. In this study, the UC rat models were established by 2,4,6-Trinitrobenzenesulfonic acid (TNBS) in vivo, while RAW264.7 cells and peritoneal macrophages were stimulated with Lipopolysaccharides/Adenosine Triphosphate (LPS/ATP) in vitro to simulate pyroptosis models, and Western blotting (WB) and other detection techniques were applied to analyze proteins involved in the NLRP3 inflammasome pathway. Our results showed that OMT alleviated colitis ulcers and pathological damage in the TNBS-induced UC rats and exhibited an inhibitory effect on pyroptosis at the early stage of UC. In the model group, the pyroptosis reached the peak at 24 h after modeling with the contents of active-cysteine-aspartic proteases-1 (caspase-1), Gasdermin D (GSDMD)-N, and cleaved-interleukin-1 beta (IL-1ß) to the highest expression level. Meanwhile, we found that OMT (80 mg kg-1) remarkably decreased the expression levels of NLRP3, active-caspase-1, and cleaved-IL-1ß at 24 h in the lesion tissue from UC rats. Further experiments on cells demonstrated that OMT at concentrations of 100 and 250 µM significantly inhibited cell death caused by NLRP3 inflammasome activation (p < 0.05), downregulated caspase-1, GSDMD, and decreased the levels of active-caspase-1, GSDMD-N, cleaved-IL-1ß in RAW326.7 cells, and peritoneal macrophages. In summary, these results indicated that OMT could attenuate ulcerative colitis through inhibiting pyroptosis mediated by the NLRP3 inflammasome. The inhibition of the NLRP3 inflammasome may be a potential strategy for UC.
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Alcaloides , Colitis Ulcerosa , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Piroptosis , Quinolizinas , Animales , Quinolizinas/farmacología , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Alcaloides/farmacología , Piroptosis/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ratones , Ratas , Inflamasomas/metabolismo , Inflamasomas/efectos de los fármacos , Células RAW 264.7 , Masculino , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Ácido Trinitrobencenosulfónico , Lipopolisacáridos , MatrinasRESUMEN
Non-linear trend detection in Earth observation time series has become a standard method to characterize changes in terrestrial ecosystems. However, results are largely dependent on the quality and consistency of the input data, and only few studies have addressed the impact of data artifacts on the interpretation of detected abrupt changes. Here we study non-linear dynamics and turning points (TPs) of temperate grasslands in East Eurasia using two independent state-of-the-art satellite NDVI datasets (CGLS v3 and MODIS C6) and explore the impact of water availability on observed vegetation changes during 2001-2019. By applying the Break For Additive Season and Trend (BFAST01) method, we conducted a classification typology based on vegetation dynamics which was spatially consistent between the datasets for 40.86 % (459,669 km2) of the study area. When considering also the timing of the TPs, 27.09 % of the pixels showed consistent results between datasets, suggesting that careful interpretation was needed for most of the areas of detected vegetation dynamics when applying BFAST to a single dataset. Notably, for these areas showing identical typology we found that interrupted decreases in vegetation productivity were dominant in the transition zone between desert and steppes. Here, a strong link with changes in water availability was found for >80 % of the area, indicating that increasing drought stress had regulated vegetation productivity in recent years. This study shows the necessity of a cautious interpretation of the results when conducting advanced characterization of vegetation response to climate variability, but at the same time also the opportunities of going beyond the use of single dataset in advanced time-series approaches to better understanding dryland vegetation dynamics for improved anthropogenic interventions to combat vegetation productivity decrease.
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Cambio Climático , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Imágenes Satelitales , Pradera , Ecosistema , Estaciones del AñoRESUMEN
BACKGROUND: Neovascular age-related macular degeneration (AMD) is responsible for the majority of severe vision loss cases and is mainly caused by choroidal neovascularization (CNV). This condition persists or recurs in a subset of patients and regresses after 5 or more years of anti-vascular endothelial growth factor (VEGF) treatment. The precise mechanisms of CNV continue to be elucidated. According to our previous studies, macrophages play a critical role in CNV. Herein, we aimed to determine the morphological changes in macrophages in CNV to help us understand the dynamic changes. METHODS: Mice were subjected to laser injury to induce CNV, and lesion expansion and macrophage transformation were examined by immunofluorescence and confocal analysis. Several strategies were used to verify the dynamic changes in macrophages. Immunofluorescence and confocal assays were performed on choroidal flat mounts to evaluate the morphology and phenotype of macrophages in different CNV phases, and the results were further verified by western blotting and RT-PCR. RESULTS: The location of infiltrated macrophages changed after laser injury in the CNV mouse model, and macrophage morphology also dynamically changed. Branching macrophages gradually shifted to become round with the progression of CNV, which was certified to be an M2 phenotypic shift. CONCLUSIONS: Dynamic changes in macrophage morphology were observed during CNV formation, and the round-shaped M2 phenotype could promote neovascularization. In general, the changes in morphology we observed in this study can help us to understand the critical role of macrophages in CNV progression and exploit a potential treatment option for CNV indicated by a shift in macrophage polarity.
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Neovascularización Coroidal , Humanos , Ratones , Animales , Neovascularización Coroidal/etiología , Neovascularización Coroidal/metabolismo , Macrófagos/metabolismo , Macrófagos/patología , Coroides/patología , Rayos Láser , Modelos Animales de Enfermedad , Ratones Endogámicos C57BLRESUMEN
3,5-Di(trifluoromethyl)phenyl(cyano)iodonium triflate is described as an accessible, stable, and powerful thiophile that can activate batches of p-tolyl thioglycoside donors at room temperature. Various alcoholic acceptors were efficiently glycosylated, providing the desired glycosides. The novel activation protocol features mild conditions as well as high compatibility with some classic strategies for the stereoselective construction of some biologically relevant glycosidic linkages, as exemplified by α-idosides, α-galactoamines, ß-mannosides, and ß-rhamnosides.
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The atmospheric CO2 growth rate (CGR) variability is largely controlled by tropical temperature fluctuations. The sensitivity of CGR to tropical temperature [Formula: see text] has strongly increased since 1960, but here we show that this trend has ceased. Here, we use the long-term CO2 records from Mauna Loa and the South Pole to compute CGR, and show that [Formula: see text] increased by 200% from 1960-1979 to 1979-2000 but then decreased by 117% from 1980-2001 to 2001-2020, almost returning back to the level of the 1960s. Variations in [Formula: see text] are significantly correlated with changes in precipitation at a bi-decadal scale. These findings are further corroborated by results from a dynamic vegetation model, collectively suggesting that increases in precipitation control the decreased [Formula: see text] during recent decades. Our results indicate that wetter conditions have led to a decoupling of the impact of the tropical temperature variation on the carbon cycle.
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Context: Drug-resistant tuberculosis (TB), especially multidrug-resistant TB, has continued to increase and pan-drug-resistant TB and even fully drug-resistant TB have emerged, bringing great challenges to the treatment of TB. Development of new, safe, and effective antituberculosis drugs is an urgent need. Objective: The study intended to evaluate the use of the network pharmacology method to comprehensively and systematically analyze the network relationship of Kushen's main components, targets, and signaling pathways, aiming to provide new ideas and clues for an in-depth study of the mechanism of Kushen's main components in the treatment of pulmonary TB. Design: The research team performed a Network pharmacology analysis. Setting: The study took place in the Department of Respiratory and Critical Care Medicine at the Third People's Hospital of Yichang City in Yichang, Hubei, China. Outcome Measures: The research team: (1) screened Kushen's active ingredients and related targets using the Traditional Chinese Medicine System Pharmacology (TCMSP) database and analysis platform; (2) used the GeneCards database and the Online Mendelian Inheritance in Man (OMIM) database to search for disease targets, (3) connected the active ingredient's targets to the disease targets to obtain predictive targets for Kushen to act against TB, (4) used the STRING database to construct a protein-protein interaction (PPI) network map, (5) used the Database for Annotation, Visualization and Integrated Discovery (DAVID) to subject the intersecting genes to gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and (6) used the TCMSP and Protein Data Bank (PDB) databases to dock the active ingredients with target-protein molecules. Results: The research team found 45 active ingredients for Kushen and 177 target-protein genes related to active ingredients. The PPI network map of the Kushen-TB targets and found that the top 10 targets of Kushen were: (1) mitogen-activated protein kinase 8 (MAPK8); (2) protein kinase B (AKT1); (3) MAPK1, (4) estrogen receptor 1 (ESR1), (5) rel avian reticuloendotheliosis viral oncogene homolog A (RELA), (6) interleukin-6 (IL6), (7) MYC proto-oncogene, basic helix-loop-helix (bHLH) transcription factor MYC), (8) retinoid X receptor alpha (RXRA), (9) FOS proto-oncogene activator protein 1 (AP-1) transcription factor subunit (FOS), and (10) JUN proto-oncogene AP-1 transcription factor subunit (JUN). The KEGG analysis suggested that Kushen can intervene in TB through the hypoxia-inducible factor 1 (HIF-1) signaling pathway. Conclusions: The network pharmacology analysis showed that Kushen's active ingredients can play a role in the treatment of TB through the HIF-1 signaling pathway.
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Medicamentos Herbarios Chinos , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Farmacología en Red , Factor de Transcripción AP-1 , Medicina Tradicional China , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéuticoRESUMEN
A wavelength sensor as a representative optoelectronic device plays an important role in many fields including visible light communication, medical diagnosis, and image recognition. In this study, a wavelength-sensitive detector with a new operation mechanism was reported. The as-proposed wavelength sensor which is composed of two parallel PtSe2/thin Si Schottky junction photodetectors is capable of distinguishing wavelength in the range from ultraviolet to near infrared (UV-NIR) light (265 to 1050 nm), in that the relationship between the photocurrent ratio of both photodetectors and incident wavelength can be numerically described by a monotonic function. The unique operation mechanism of the thin Si based wavelength sensor was unveiled by theoretical simulation based on Synopsys Sentaurus Technology Computer Aided Design (TCAD). Remarkably, the wavelength sensor has an average absolute error of ±4.05 nm and an average relative error less than ±0.56%, which are much better than previously reported devices. What is more, extensive analysis was performed to reveal how and to what extent the working temperature and incident light intensity, and the thickness of the PtSe2 layer will influence the performance of the wavelength sensor.
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Rayos Infrarrojos , Rayos Ultravioleta , Diseño Asistido por Computadora , Rayos Ultravioleta/efectos adversosRESUMEN
BACKGROUND: To evaluate quantitative changes in iris blood circulation in patients with ischemic risk. METHODS: This observational case-control study included 79 patients with diabetic retinopathy (DR) and retinal vein occlusion (RVO). The RVO group included 21 patients; the monocular proliferative diabetic retinopathy (PDR) group included 19 patients; the nondiabetic retinopathy (NDR) group included 18 patients; and the healthy control group included 21 healthy controls. In the RVO group, we analyzed RVO affected eyes, RVO contralateral eyes, and healthy control eyes. We also compared eyes with PDR and contralateral eyes without PDR, patients with diabetes mellitus (DM) without DR, and healthy control eyes. The microvascular networks of the iris and retina were analyzed using optical coherence tomography angiography. The analysis included vessel area density (VAD) and vessel skeleton density (VSD) of iris and retina. RESULTS: In the RVO group, the VAD and VSD of iris in the affected eye were higher than those in contralateral and healthy control eyes, and the VAD and VSD of contralateral eyes were higher than those of healthy control eyes. The retinal blood flow of the RVO eyes was less than that of the contralateral and healthy control eyes, but there were no difference between the contralateral eyes and healthy control eyes. The VAD and VSD of iris in PDR were larger than nonproliferative diabetic retinopathy (NPDR) and the NPDR were larger than NDR. There were no differences between NDR and healthy control eyes. Also, there were no differences among the four groups with respect to retinal blood flow. CONCLUSIONS: Compared with the retina, iris blood circulation quantitative analysis data seem to be more sensitive to ischemia and may be used as a new predictor of ischemic disease, even if further research is needed to better understand the clinical value and importance of this analysis. TRIAL REGISTRATION: The trial is registered with the clinical trial registration number nct03631108 .
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Retinopatía Diabética , Vasos Retinianos , Estudios de Casos y Controles , Angiografía con Fluoresceína , Humanos , Iris/diagnóstico por imagen , Isquemia , Vasos Retinianos/diagnóstico por imagenRESUMEN
Ultraviolet photodetectors (UVPDs) based on wide band gap semiconductors (WBSs) are important for various civil and military applications. However, the relatively harsh preparation conditions and the high cost are unfavorable for commercialization. In this work, we proposed a non-WBS UVPD by using a silicon nanowire (SiNW) array with a diameter of 45 nm as building blocks. Device analysis revealed that the small diameter SiNW array covered with monolayer graphene was sensitive to UV light but insensitive to both visible and infrared light illumination, with a typical rejection ratio of 25. Specifically, the responsivity, specific detectivity, and external quantum efficiency under 365 nm illumination were estimated to be 0.151 A/W, 1.37 × 1012 Jones, and 62%, respectively, which are comparable to or even better than other WBS UVPDs. Such an abnormal photoelectrical characteristic is related to the HE1m leaky mode resonance (LMR), which is able to shift the peak absorption spectrum from near-infrared to UV regions. It is also revealed that this LMR is highly dependent on the diameter and the period of the SiNW array. These results show narrow band gap semiconductor nanostructures as promising building blocks for the assembly of sensitive UV photodetectors, which are very important for various optoelectronic devices and systems.
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In this study, we present a wavelength sensor that is capable of distinguishing the spectrum in the range from ultraviolet (UV) to near-infrared (NIR) light. The filterless device is composed of two horizontally stacking PdSe2/20 µm Si/PdSe2 heterojunction photodetectors with a photovoltaic (PV) behavior, which makes it possible for the device to work at 0 bias voltage. Due to the relatively small thickness of Si and the wavelength-dependent absorption coefficient, the two PdSe2/20 µm Si/PdSe2 photodetectors according to theoretical simulation display a sharp contrast in distribution of the photoabsorption rate. As a result, the photocurrents of both photodetectors evolve in completely different ways with increasing wavelengths, leading to a monotonic decrease in the photocurrent ratio from 6800 to 22 when the wavelength gradually increases from 265 to 1050 nm. The corresponding relationship between both the photocurrent ratio and wavelength can be easily described by the monotonic function, which can help to precisely determine the wavelength in the range from 265 to 1050 nm, with an average relative error less than ±1.6%. It is also revealed that by slightly revising the monotonic function, the wavelength in other different temperatures can also be estimated.
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Purpose: To create a mouse traumatic optic neuropathy (TON) model that is reproducible, reliable, and easy to manipulate with high specificity to retinal ganglion cell (RGC) layer and no mortality. The model will be useful for understanding the pathophysiology of retinal ganglion cell death and for testing neuroprotective therapeutics. Methods: An Nd:YAG laser was used to generate focal photodisruptive retinal damage. Noninvasive in vivo ophthalmologic imaging technologies such as optical coherence tomography (OCT) and confocal laser scanning ophthalmoscopy (CSLO) were used to longitudinally track the retinal nerve fiber layer (RNFL) thickness and RGC number change, respectively. Immunostaining and pattern electroretinography (PERG) were also used to evaluate structure and functional change after laser injury. Results: Our ND:YAG laser generates a concussive photodisruptive laser shockwave force which induces focal RGC death in the targeted area. We observed a correlative decrease in RGCs number, RNFL, and PERG function of RGC in the laser zone. The pattern of RNFL thinning and RGC soma loss correlates with the pattern and amount of fluorescence loss on OCT and CSLO images, respectively. The ND:YAG laser does not cause any damage to other layers in the retina nor any side effects including changes in intraocular pressure, corneal edema, and calcification or mortality (which has been observed in other TON models). Conclusions: We have created a new and novel RGC TON death model that confers no mortality and produces a quantifiable decrease in RGC number and function. The laser targeted regions of the retina correlate with both in vivo imaging by OCT and CSLO and histologically with regions of RGC loss without ophthalmic side effects. Translational Relevance: This laser-based TON injury model is simple to implement, is reproducible, and is useful for determining the molecular and cellular pathophysiology of TON and RGC death and for testing neuroprotective therapeutics.
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Traumatismos del Nervio Óptico , Células Ganglionares de la Retina , Animales , Rayos Láser , Ratones , Tomografía de Coherencia Óptica , Tonometría OcularRESUMEN
The karst area in Yunnan-Guangxi-Guizhou region in southwest China is known for widespread rocky desertification but several studies report a greening trend since the year 2000. While the start of the greening trend seems to match with the implementation of ecological conservation projects, no statistical evidence on a relationship between vegetation greening and eco-engineering exists. Moreover, dominant factors influencing the spatial patterns of vegetation trends have rarely been investigated. Here we use six comprehensive factors representing the natural conditions and human activities of the study area, and several statistical models consistently show that eco-engineering explains large parts of the positive vegetation trends in the karst areas, while negative vegetation trends in non-karst areas of Yunnan were related with a decrease in rainfall. We further show that the interaction of eco-engineering with other factors leads to a heterogeneous pattern of different vegetation trends. Knowing and understanding these patterns is crucial when planning ecological restoration, especially in diverse landscapes like China karst and the methods can be reused in other restoration areas.
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Conservación de los Recursos Naturales , Ecosistema , China , Ingeniería , Actividades Humanas , HumanosRESUMEN
The Tibetan Plateau is the highest and largest plateau in the world, hosting unique alpine grassland and having a much higher snow cover than any other region at the same latitude, thus representing a "climate change hot-spot". Land surface phenology characterizes the timing of vegetation seasonality at the per-pixel level using remote sensing systems. The impact of seasonal snow cover variations on land surface phenology has drawn much attention; however, there is still no consensus on how the remote sensing estimated start of season (SOS) is biased by the presence of preseason snow cover. Here, we analyzed SOS assessments from time series of satellite derived vegetation indices and solar-induced chlorophyll fluorescence (SIF) during 2003-2016 for the Tibetan Plateau. We evaluated satellite-based SOS with field observations and gross primary production (GPP) from eddy covariance for both snow-free and snow covered sites. SOS derived from SIF was highly correlated with field data (R2 = 0.83) and also the normalized difference phenology index (NDPI) performed well for both snow free (R2 = 0.77) and snow covered sites (R2 = 0.73). On the contrary, normalized difference vegetation index (NDVI) correlates only weakly with field data (R2 = 0.35 for snow free and R2 = 0.15 for snow covered sites). We further found that an earlier end of the snow season caused an earlier estimate of SOS for the Tibetan Plateau from NDVI as compared to NDPI. Our research therefore adds new evidence to the ongoing debate supporting the view that the claimed advance in land surface SOS over the Tibetan Plateau is an artifact from snow cover changes. These findings improve our understanding of the impact of snow on land surface phenology in alpine ecosystems, which can further improve remote sensing based land surface phenology assessments in snow-influenced ecosystems.
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Platinum telluride (PtTe2) has garnered significant research enthusiasm owing to its unique characteristics. However, large-scale synthesis of PtTe2 toward potential photoelectric and photovoltaic application has not been explored yet. Herein, we report direct tellurization of Pt nanofilms to synthesize large-area PtTe2 films and the influence of growth conditions on the morphology of PtTe2. Electrical analysis reveals that the as-grown PtTe2 films exhibit typical semimetallic behavior, which is in agreement with the results of first-principles density functional theory (DFT) simulation. Moreover, the combination of multilayered PtTe2 and Si results in the formation of a PtTe2/Si heterojunction, exhibiting an obvious rectifying effect. Moreover, the PtTe2-based photodetector displays a broadband photoresponse to incident radiation in the range of 200-1650 nm, with the maximum photoresponse at a wavelength of â¼980 nm. The R and D* of the PtTe2-based photodetector are found to be 0.406 A W-1 and 3.62 × 1012 Jones, respectively. In addition, the external quantum efficiency is as high as 32.1%. On the other hand, the response time of τrise and τfall is estimated to be 7.51 and 36.7 µs, respectively. Finally, an image sensor composed of a 8 × 8 PtTe2-based photodetector array was fabricated, which can record five near-infrared (NIR) images under 980 nm with a satisfying resolution. The result demonstrates that the as-prepared PtTe2 material will be useful for application in NIR optoelectronics.
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BACKGROUND: To investigate the distribution of peripheral anterior chamber depth (ACD) and the relationship between peripheral ACD and gonioscopy compared to other ocular parameters for primary angle closure disease (PACD) screening. We performed a population-based survey in Pudong New District of Shanghai, China, in 2011. METHODS: Cross-sectional study. Adults 50 and older were enrolled from a population-based study using cluster random sampling in Pudong New District, Shanghai. Remote ocular screening was performed with digital anterior eye structure photography. Van Herrick measurements were used to evaluate the peripheral ACD, the depth of the peripheral anterior chamber, and corneal thickness (CT), and the ACD to CT ratio was calculated. Subjects with peripheral ACD less than 0.5 CT were made follow-up appointments for clinical examination with gonioscopy. Receiver operating characteristic curves (ROC) were generated to show the performance of different tests in screening for primary angle closure disease (PACD). RESULTS: Two thousand five hundred twenty-eight adults participated in the study with 91 patients diagnosed with PACD. Two thousand four hundred sixty-three subjects had valid data in the right eye available for analysis. The mean peripheral ACD values for men and women were significantly different: 1.04 ± 0.46 (range 0.11-2.93) CT and 0.87 ± 0.41 (range 0.12-2.96) CT respectively (t = - 4.18; P<0.0001). Multivariate logistic regression analysis reveals that peripheral ACD declined by 0.31 CT (P < 0.0001) per diopter of SE and was 0.19 CT (P < 0.0001) shallower in women than in men (r2 = 0.1304, P < 0.0001). Peripheral ACD performed best in screening for PACD. CONCLUSIONS: Peripheral ACD measurement is recommended for PACD screening in community elderly Chinese.
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Glaucoma de Ángulo Cerrado , Adulto , Anciano , Cámara Anterior/diagnóstico por imagen , China/epidemiología , Estudios Transversales , Femenino , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Cerrado/epidemiología , Gonioscopía , Humanos , Presión Intraocular , MasculinoRESUMEN
Land use policies have turned southern China into one of the most intensively managed forest regions in the world, with actions maximizing forest cover on soils with marginal agricultural potential while concurrently increasing livelihoods and mitigating climate change. Based on satellite observations, here we show that diverse land use changes in southern China have increased standing aboveground carbon stocks by 0.11 ± 0.05 Pg C y-1 during 2002-2017. Most of this regional carbon sink was contributed by newly established forests (32%), while forests already existing contributed 24%. Forest growth in harvested forest areas contributed 16% and non-forest areas contributed 28% to the carbon sink, while timber harvest was tripled. Soil moisture declined significantly in 8% of the area. We demonstrate that land management in southern China has been removing an amount of carbon equivalent to 33% of regional fossil CO2 emissions during the last 6 years, but forest growth saturation, land competition for food production and soil-water depletion challenge the longevity of this carbon sink service.
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In this work, a sensitive deep ultraviolet (DUV) light photodetector based on inorganic and lead-free Cs3Cu2I5 crystalline film derived by a solution method was reported. Optoelectronic characterization revealed that the perovskite device exhibited nearly no sensitivity to visible illumination with wavelength of 405 nm but exhibited pronounced sensitivity to both DUV and UV light illumination with response speeds of 26.2/49.9 ms for rise/fall time. The Ilight/Idark ratio could reach 127. What is more, the responsivity and specific detectivity were calculated to be 64.9 mA W-1 and 6.9 × 1011 Jones, respectively. In addition, the device could keep its photoresponsivity after storage in air environment for a month. It is also found that the capability of Cs3Cu2I5 crystalline film device can readily record still DUV image with acceptable resolution. The above results confirm that the DUV photodetector may hold great potential for future DUV optoelectronic device and systems.
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Compuestos de Calcio/química , Cesio/química , Cobre/química , Diseño de Equipo/instrumentación , Yoduros/química , Óxidos/química , Titanio/química , Cristalización , Técnicas Electroquímicas/métodos , Cinética , Membranas Artificiales , Procesos Fotoquímicos , Fenómenos Físicos , Propiedades de Superficie , Termodinámica , Rayos UltravioletaRESUMEN
OBJECTIVE: To explore the effects of cluster needling at the scalp points on the expression of choline acetyl transferase (ChAT) and choline cholinesterase (AchE). METHODS: A total of 60 Wistar rats were randomized into a sham-operation group, a model group, a medication group and a cluster needling group, 15 rats in each one. In the model group, the medication group and the cluster needling group, the models of Alzheimer's disease (AD) were established by the orienteering injection with Aß1-42 in the bilateral hippocampal CA1 in the rats. In the sham-operation group, the distilled water was injected in bilateral hippocampus of rats. In the medication group, the lavage with aricept was adopted for the basic treatment, once a day, for 4 weeks consecutively. In the cluster needling group, on the base of the treatment as the medication group, the cluster needling at the scalp points was adopted, once a day, 6 times a week, for 4 weeks totally. In the sham-operation group and the model group, the normal feeding was provided. After intervention, the learning and memory ability was measured with Morris water maze in the rats of each group. The changes in the hippocampal gross structure were observed with HE staining. The changes in the positive expressions of hippocampal ChAT and AchE were determined with the immunohistochemical method. RESULTS: Compared with the sham-operation group, the escape latency was prolonged and the percentage of the second quadrant and the frequency of platform leaping were reduced in the rats of the model group (all P<0.01). Compared with the model group, the escape latency was shortened and the percentage of the second quadrant and the frequency of platform leaping were increased in the rats of the cluster needling group and the medication group (P<0.05, P<0.01). Compared with the medication group, the escape latency was shortened and the percentage of the second quadrant and the frequency of platform leaping were increased in the rats of the cluster needling group (all P<0.05). Compared with the sham-operation group, the expression of ChAT was decreased and that of AchE increased in the model group (both P<0.01). Compared with the model group, the difference was not significant in ChAT expression (P>0.05) and the expression of AchE was reduced (P<0.05) in the medication group; the expression of ChAT was increased (P<0.05) and that of AchE decreased (P<0.01) in the cluster needling group. Compared with the medication group, the expression of ChAT was increased and that of AchE decreased in the cluster needling group (both P<0.05). CONCLUSION: The effect mechanism of cluster needling at the scalp points on AD could be related to the up-regulation of ChAT expression and down-regulation of AchE expression in the hippocampus. The combined treatment with the cluster needling and aricept achieves the better therapeutic effect on AD.
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Enfermedad de Alzheimer , Animales , Colina O-Acetiltransferasa , Hipocampo , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Cuero CabelludoRESUMEN
Photocoupler is a kind of semiconductor optoelectronic device that integrates light-emitting device (LED) and photodetector. It has found wide application in various fields because of its capability to transmit the electrical signal through the conversion of the electricity-light-electricity. Herein, we report the fabrication of a new photocoupler by simply integrating perovskite quantum dots LED and perovskite photodetector on a glass substrate. The as-fabricated photocoupler showed outstanding characteristics with high current transfer ratio (CTR) of 3.35%, which is highly competitive in comparison with other materials based devices. Furthermore, the perovskite photocoupler had a fast response speed of 8 µs/8.26 µs. By further adding an amplification circuit, the CTR could be enhanced by around 50 times to 172.6%. These results indicate that the present perovskite-based photocouplers may find potential application in future integrated circuit and optoelectronic system.
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In this article, we fabricated a sensitive near-infrared (NIR) light detector by directly coating a layer of Cs-doped FAPbI3 perovskite film onto vertical Si nanowire (SiNW) array. The as-assembled SiNW array/perovskite core-shell heterojunction exhibits a typical rectifying characteristic in darkness and distinct photoresponse characteristics under light illumination. Owning to the remarkable photovoltaic effect, the heterojunction can work as a self-driven NIR detector without an exterior energy supply. Further photoresponse investigation reveals that the photodetector is sensitive in a wide wavelength range with maximum sensitivity at â¼850 nm. The responsivity ( R) and specific detectivity ( D*) are estimated to be 14.86 mA W-1 and 2.04 × 1010 Jones at 0 V bias, respectively, which can be improved to 844.33 mA W-1 and 3.2 × 1011 Jones at a bias voltage of -0.9 V. In addition, the present device also possesses distinct advantages of a large Ilight/ Idark ratio exceeding 104, swift response rate with rise/decay times of 4/8 µs, and relatively good ambient stability. According to our numerical simulation based on finite element method, the superior device performance is associated with strong light-trapping effect in such unique core-shell heterojunction array.