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Background Cerebral ischemia is associated with a high burden of neurological disability. Recently, emerging evidence has demonstrated that long non-coding RNAs (lncRNAs) are crucial regulators in cerebral ischemia reperfusion (I/R) injury. Herein, we investigated the function and potential mechanism of long intergenic non-protein coding RNA 473 (LINC00473) in cerebral I/R injury. Methods We established oxygen glucose deprivation/reperfusion (OGD/R) model in Neuro-2a (N2a) cells to mimic the cerebral I/R injury in vitro. RT-qPCR and Western blot assays were conducted to detect target gene expression. Functional assays measured the effects of LINC00473 on cell viability, apoptosis and reactive oxygen species (ROS) production. A series of mechanism assays were carried out to detect the potential mechanism of LINC00473 in cerebral I/R injury. Results LINC00473 was significantly down-regulated in OGD/R-induced injury model. LINC00473 overexpression reversed the reduced cell viability as well as the enhanced apoptosis and ROS level induced by OGD/R. Moreover, LINC00473 functioned as a competing endogenous RNA (ceRNA) to sponge miR-15b-5p and miR-15a-5p and thereby regulated SRSF protein kinase 1 (SRPK1) expression. Conclusions Our findings confirmed the protective role of LINC00473 in cerebral I/R injury, which might provide a novel target for treating ischemic brain injury.

Background Ischemic encephalopathy is a common clinical disease. The main treatment goal is to achieve vascular recanalization. However, after vascular recanalization, the reperfusion of fresh blood can change local cell metabolism, thus adversely affecting cell structure and function, which can result in reperfusion injury. Objectives To explore the effect of matrine intervention of different concentrations on JAK2/STAT3 signaling pathway and brain protection in rats with cerebral ischemia-reperfusion. Material and methods Healthy male Sprague Dawley rats were divided into a blank control group (20 rats), a model group (80 rats) and a sham group (20 rats). In the model group, the middle cerebral artery was occluded with suture method to establish cerebral ischemia-reperfusion model rats, which were subdivided into cerebral ischemia-reperfusion group, and 5, 10 and 20 mg/kg matrine groups, with 20 rats in each group. Indicators including neurological function score, brain infarct size, brain water content, lactic dehydrogenase activity, protein expressions of p-JAK2 and p-STAT3, as well as superoxide dismutase activity and malondialdehyde content were evaluated. Results Compared with cerebral ischemia-reperfusion group, all the indicators were significantly improved in the 3 matrine treatment groups in a dose-dependent manner, and protein expressions of p-JAK2 and p-STAT3 in the brain tissue and brain cell apoptosis rate were decreased with the increase of matrine concentration (all p Conclusions Matrine can significantly ameliorate the neurological function and brain edema of rats with cerebral ischemia-reperfusion, and improve superoxide dismutase, malondialdehyde and lactic dehydrogenase levels in the brain tissue and brain cell apoptosis rate. The mechanism of matrine may be related to the inhibition of abnormal JAK2/STAT3 signaling pathway activation.

When setting the goal of landscape sustainability in landscape management, a key theoretical question should be which landscape patterns are more sustainable, whereas there were few studies that further compared optimization scenarios. This article sought to identify the future scenario of landscape services and the most sustainable landscape in the Qinghai-Tibet Plateau. This study adopts the parameter of ecological security pattern (ESP) combining with landscape connectivity and landscape service as indicators to assess the sustainability of landscape patterns in 2010, 2020 and 2030 with different land use scenarios in Representative Concentration Pathways. The results showed that (1) the area with high quality of the three landscape services was mainly concentrated in the southeast of the Qinghai-Tibet Plateau, where a large area of forest was distributed, and the low quality area was located in the northwest, which was bare land in 2010; (2) the landscape services showed a declining trend under the RCP 2.6 and RCP 4.5 scenarios from 2020 to 2030, whereas the values remained stable under the RCP 6.0 and RCP 8.5 scenarios; and (3) there were 9 ecological sources and 16–17 corridors within the ESP scenarios with quantitative parameters to indicate the landscape sustainability of the scenarios. The approach of this study showed the possibility of using ESP scenarios to quantitatively indicate the sustainability of landscape patterns and provide guidance for future landscape management.

The atomic mechanisms of the melting process of gold nanoparticles were investigated by molecular dynamics simulations. The melting under high heating rate is found to be much different from the ne...

Normal melting invariably starts from surfaces or interfaces due to the weaker bonding constraints in these regions. However, we show that melting can be initiated from the interior of gold nanoparticles with high heating rates. We find that melting starts from the surface with the formation of a premelting layer, as usual, but that the premelting layer does not extend to the interior under certain conditions. Instead, liquid nucleation occurs in the core of the nanoparticle. This unexpected interior melting is connected to the slower melting kinetics, which is related to heat transfer near the premelted surface. The required conditions for interior melting are a suitable size of the nanoparticle and a sufficiently fast heating rate. The present results point to a novel melting regime in nanoparticles. We note that the time scales are now accessible using ultrafast tools such as X-ray lasers that can probe dynamical structure changes, suggesting opportunities for experiments.

The evaluation of the development of a land-sea coordination system, including how to measure success, remains a significant subject for exploration among researchers and practitioners. The main challenge in this subject is to establish a suitable indicator system. In this paper, we propose a novel approach to construct an indicator system to evaluate the development of a land-sea coordination system. We take Lianyungang port as a case study. A land-sea coordination system is considered as composed by three sub-systems, i.e., a land-side sub-system, a sea-side sub-system, and a port sub-system. Based on analysis of influential factors using questionnaires for the development of a land-sea coordination system, an initial indicator system is established. We apply structural equation modeling to screen the indicators from the initial indicator system. Finally, we analyze the reliability and validity of the screened indicator system. The results show that a total of 26 indicators are generated and grouped into three major categories: (1) economic development; (2) service system; (3) resources and environment, and the screened indicator system is of suitable feasibility to be applied to evaluate the development of the considered land-sea coordination system. Additionally, the results provide a scientific reference and decision-making basis for policy formulation and development evaluation of standard ports.

Background and purpose: Data concerning the learning curve for endovascular treatment (EVT) of anterior circulation large vessel occlusion are scarce. This study aimed to investigate the relationship between operator experience and the outcome of EVT and to further identify the number of cases needed to acquire the ability to perform successful reperfusion.Materials and methods: Four hundred and thirty-four patients who underwent EVT by seven operators at a single center from January 2016 to September 2019 were enrolled. Procedural experience was defined by the number of cases performed by each operator. Multivariable backward regression analyses were used to investigate the association between procedural experience and functional independence (defined as a modified Rankin Scale score of 0–2), 90-days mortality, successful reperfusion (defined as a modified Thrombolysis in Cerebral Infarction score of 2b-3), and puncture-to-reperfusion time after adjusting for covariates. A risk-adjusted cumulative sum (RA-CUSUM) chart was utilized to identify the number of caseloads needed to overcome the learning curve effect.Results: Procedural experience was independently associated with functional independence, 90-days mortality, successful reperfusion, and puncture-to-reperfusion time reduction (per 10-case increment: OR 1.219, 95% CI: 1.079–1.383, P < 0.001; OR 0.847, 95% CI: 0.738–0.968, P = 0.016; OR 1.553, 95% CI: 1.332–1.830, P < 0.001 and β 8.087 min, 95% CI: 6.184–9.991, P < 0.001, respectively). The RA-CUSUM chart indicated that at least 29 cases were required to overcome the learning curve effect.Conclusions: There was a dose-response relationship between operator case volume and clinical outcome, procedure time, and successful reperfusion. The experience needed for successful EVT was at least 29 cases.

The NaBaPO4:Eu2+,Yb3+ quantum-cutting (QC) phosphors were prepared by the solid-state reaction. We confirm the luminescence of Yb3+ is mainly derived from QC rather than common down-conversion. The QC efficiency ηQE calculated from the luminescence decay curves reached a maximum as high as 197.4%. Furthermore, the QC emission was enhanced by decorating with quasi-spherical and uniform (∼100 nm) Ag nano-particles, due to localized surface plasmon resonance. The enhancement factor reached a maximum as 1.2337.

Facing the demands of biodiversity conservation and ecosystem service improvement, the spatial pattern optimization of nature reserves has always been a research topic of interest. However, there remains a lack of methodological guidance in the planning of nature reserves and the surrounding areas. To promote the landscape sustainability of nature reserves, we constructed ecological security patterns (ESPs) with two scenarios as a case study in Wenchuan, China. In detail, the ecological sources were identified by ecosystem service evaluation, and the resistance surface was characterized by the habitat quality. The ecological corridors were determined based on circuit theory and the minimum cumulative resistance model. The ecological sources were mainly aggregated in the protected areas, with an area of more than 1000 ha, the high-resistance values were mainly in the area with dense roads or high elevation. There were 21 corridors in the scenario of only optimizing the nature reserve, while 31 corridors were identified when considering non-nature reserves, and the landscape connectivity was enhanced accordingly. The result supported constructing the ESPs between nature and non-nature reserves in Wenchuan to further protect pandas, and a methodological contribution was made to understand the differences of ESPs between them, thus supporting a methodological formulation of sustainable landscape patterns.

The understanding of the local spatiotemporal characteristics of the relationships among ecosystem services provides an ecological basis for regional sustainable ecosystem management. However, the geographical factors that influence the different changing relationships among the ecosystem services remain unclear, especially for continent-scale future scenarios. In this study, five ecosystem services (ESs) (habitat quality (HQ), soil retention (SR), water yield (WY), crop production (CP) and carbon sequestration (CS)) were measured in the “Belt and Road” region from 2010 to 2030. We qualified the trade-off and synergy among the ESs using Pearson correlations in different ecoregions, at different altitudes and for different population levels. Our results showed that CP exhibited a trade-off with HQ and SR, whereas the relationships among the other ESs were synergistic. Under the RCP4.5 scenario, the synergies between CP and CS and between CP and WY were the strongest, while the trade-offs between CP and SR and between CP and HQ were the strongest under RCP8.5. The relationship of the ecosystem services corresponded well with the regional climate, altitude and population, and the responses of the relationships among ESs to population sizes were the most obvious. This study contributes to investigating the influence of the driving factors on the relationships among ESs under multiple scenarios at the continental scale and could provide credible associations for future land use management and economic development in various countries, as well as promoting construction of a “green Belt and Road”.

A series of CaFCl:Tb3+ and CaFCl:Tb3+,A+ (A=Li, Na and K) nanophosphors were synthesized by the one-step sol-gel method, which were reported for the first time. The sample consisted of monodisperse particles, the average size of which was 37 nm. The emissions of Tb3+ ions and oxygen defects OF? were demonstrated in the CaFCl:Tb3+ samples. The former was made up of several peaks at 488, 545, 587 and 623 nm, ascribed to 5D4→7FJ (J=6−3) transitions of Tb3+ ions. The latter was shown as a broad band peaked at about 450 nm. Alkali metal ions A+ (A=Li, Na and K) were introduced as the charge compensators to improve the luminescence of samples. The influence of charge compensators on the emissions of Tb3+ ions and oxygen defects OF? was investigated by the measurement of fluorescence spectra and luminescence decay curves. The results indicated that all the charge compensators weakened the defects emission. Furthermore, Li+ ion was the best charge compensator, because it not only reduced the defects emission but also increased the emission intensity of Tb3+ significantly. Our results suggested that this nanophosphor sensitized by the charge compensator might broaden potential applications of rare-earth doped CaFCl.

A new kind of quantum-cutting (QC) phosphor KYF 4 :Tb 3+ ,Yb 3+ was prepared by the sol–gel method by using trifluoroacetic acid as a fluorine source. Tb 3+ -doped samples represent high quenching concentration as 15%. The near-infrared fluorescence spectra of Tb 3+ &Yb 3+ co-doped samples with high Tb 3+ concentration (15%) indicate that QC can occur under different excitations of Tb 3+ , and the 7 F 6 → 5 D 3 excitation (∼374 nm) is more effective than 7 F 6 → 5 D 4 excitation (∼483 nm). Through the lifetime measurement, the maximum of QC efficiency ( η QE ) under 7 F 6 → 5 D 4 and 7 F 6 → 5 D 3 excitations are calculated as 161% and 150%, respectively. The results all above infer that this phosphor can make use of high-energy photons of several wavelengths and may raise the conversion efficiency of solar cells greatly.

With four soils differing in K supplying power and with four rice cultivars (Oryza sativa L.) differing in K uptake kinetic parameters, the relationship between K fertilizer application and soil redox status in rhizosphere and; the distribution of ferrous iron and other toxic substances on the root surface and in the rhizosphere; and the effect of K supply on uptake of reduced iron by rice plants have been studied. The results show that K application on K-deficient soils reduced the content of active reducing substances and ferrous iron in the soil, raised the soil redox potential in the rhizosphere, increased the Eh value of rice roots and lowered the content of iron in the rice plants. These effects of K varied with different rice cultivars. When no K fertilizer was applied, active reducing substances and ferrous iron in rhizosphere soils were decreased more by the rice cultivars absorbing K strongly (e.g. Shanyou 64) than by cultivars absorbing K weakly (e.g. Zhongguo 91). Therefore, the diminution of the toxic substances by K application in the weakly K-absorbing cultivars was more significant. The observation of a rhizobox separated by a nylon screen showed that appreciably more iron oxides, compared with the control, were deposited at or adjacent to the root surfaces of the rice plant supplied with K fertilizer, fully demonstrating the relationship between K nutrition and the total oxidizing power of rice plants. According to the distribution of active reducing substances and ferrous iron, the oxidizing range of the rice root extended in K application treatment a few centimeters away from the root plane. K application to rice affected the soil redox status in rhizosphere in many ways. The main effect was an increase of the oxidizing power of the rice root. As a result, the value of soil Eh was increased, the contents of active reducing substances and ferrous iron were lowered, as well as the number of oxygen consuming microorganisms.