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The main function zone (MFZ) is the major strategy of China’s economic development and ecological environment protection. Clarifying the logical relationship between “MFZ strategy” and “territorial spatial layout” is vital to construct regional economic layout and territorial spatial supporting system of high-quality development. However, few studies have revealed the evolution process and formation mechanism of the production-living-ecological space (PLES) structure of China’s MFZ over a long period of time. To bridge the gap, based on the land use dataset in China from 1980 to 2020, this study analyzed the evolution patterns of PLES in China’s MFZs using multiple methods and measured the formation mechanism of PLES in different types of MFZs with the GeoDetector model. Results showed that the spatial structure of China’s national territory has evolved drastically in the past 40 years, showing significant horizontal regional differentiation and vertical gradient differentiation. Ecological space has been continuously decreasing, while production space and living space have been continuously increasing, and the evolution of PLES varied significantly in different MFZs. During the study period, the gravity center of PLES in China all moved westward. The spatial distribution pattern of production space and living space was from northeast to southwest, and the ecological space was from east to west. The evolution of China’s territorial spatial structure was subject to the combined effects of natural and socio-economic factors, exhibiting significant differences in different MFZs. Land use intensity had the most prominent influence on the formation of PLES, followed by elevation. The influences of different factors on PLES structure were strengthened mainly through two types of nonlinear enhancement and dual-factor enhancement. This study can provide scientific support for the optimal management and high-quality development of territorial space in China.

BACKGROUND High-intensity focused ultrasound (HIFU) is a promising and non-invasive therapy for symptomatic uterine fibroids. Currently, the main image-guided methods for HIFU include magnetic resonance-guided (MR-HIFU) and ultrasound-guided (US-HIFU). However, there are few comparative studies on the therapeutic efficacy and safety of MR-HIFU and US-HIFU in treating symptomatic uterine fibroids with a volume

Adhesion G-protein-coupled receptors (aGPCRs) play key roles in a diversity of physiologies. A hallmark of aGPCR activation is the removal of the inhibitory GAIN domain and the dipping of the cleaved stalk peptide into the ligand-binding pocket of receptors; however, the detailed mechanism remains obscure. Here, we present cryoelectron microscopy (cryo-EM) structures of ADGRL3 in complex with G

Background: Teratoma is the most common germ cell tumor, and the incidence varies greatly in different age, gender, and tissues, among which, the mature teratoma of the liver is exceedingly rare. For the present, there are fewer than 50 cases of primary hepatic teratomas reported in English literature, especially the left lobe teratoma, with a lower incidence. At present, histological examination can make a definitive diagnosis for the disease along with the assessment of maturity. Surgical resection is widely adopted as the best treatment scheme.Case presentation: A 17-year-old female complained that the liver occupied over 2 years. No obvious symptoms and special abnormalities were revealed on physical examination. She suffered from anemia and the anemia recovered after a blood transfusion. After completing tumor markers, ultrasonography (US) of abdomen, abdomen plain computed tomography (CT) scan and enhanced magnetic resonance imaging (MRI), the tumor was tentatively judged as benign tumor of the liver, which was detected located in the left lobe of the liver with cystic structure. Histological examination confirmed mature teratoma. The patient recovered. Nevertheless, tendency of recurrence and deterioration were hard to evaluate due to the short follow-up. Conclusion: Mature hepatic teratomas are extremely rare. The accumulation of further cases is necessary to help recognize the histology, diagnosis, and treatment of this disease.

It has been established that poor outcomes in ischemic stroke patients are associated with the post-reperfusion inflammatory response and up-regulation of TLR4. Therefore, suppression of the TLR4 signaling pathway constitutes a potential neuroprotective therapeutic strategy. Schisandrin B, a compound extracted fromI/R: schemia/reperfusion; IL: interleukin; MCAO/R: middle cerebral artery occlusion and reperfusion; NF-κB: nuclear; TLR4: Toll-like receptor 4; TNF-α: tumor necrosis factor-α.

A sound ecosystem is the prerequisite for the sustainable development of human society, and the karst ecosystem is a key component of the global ecosystem, which is essential to human welfare and livelihood. However, there remains a gap in the literature on the changing trend and driving factors of ecosystem services value (ESV) in karst areas. In this study, Guizhou Province, a representative region of karst mountainous areas, was taken as a case to bridge the gap. ESV in the karst areas was predicted, based on the land use change data in 2009–2018, and the driving mechanisms were explored through the gray correlation analysis method. Results show that a total loss of CNY 21.47 billion ESV from 2009 to 2018 is due to the conversion of a total of 22.566% of the land in Guizhou, with forest land as the main cause of ESV change. By 2025 and 2030, the areas of garden land, water area, and construction land in Guizhou Province will continue to increase, whereas the areas of cultivated land, forest land, and garden land will decline. The total ESV shows a downward trend and will decrease to CNY 218.71 billion by 2030. Gray correlation analysis results illuminate that the total population and tertiary industry proportion are the uppermost, among all the driving factors that affect ESV change. The findings in this study have important implications for optimizing and adjusting the land use structure ecological protection and will enrich the literature on ESV in ecologically fragile areas.

In recent decades, substantial changes have occurred in the spatial structure and form of landscapes in metropolises; these have greatly impacted ecosystem provision capacities. Clarifying the impact mechanism of landscape patterns on ecosystem services can provide insights into regional ecological conservation and sustainable development measures. Although previous studies have explored the impacts of landscape patterns on ecosystem services at multiple scales, few studies have been conducted using the buffer gradient analysis approach. Using land-use/cover change data, this study measured the evolution of spatiotemporal features of landscape patterns and ecosystem services value (ESV) with 1, 2, and 3 km buffer-zone scales in Wuhan, China. Econometric models were then used to analyze the impacts of landscape patterns on ecosystem services at different buffer-zone scales. The results demonstrated that rapid urbanization in Wuhan has led to significant changes in landscape patterns, and the landscape pattern metrics exhibited significant spatial heterogeneity. The ESV in Wuhan exhibited a steady decline during the study period. Hydrological regulations and waste treatment functions contributed to the largest proportion of ESV, and raw material production functions contributed to the lowest proportion. Landscape pattern metrics exerted a significant influence on ESV; however, this influence varied greatly. The results of this study provide a new understanding of the influence mechanism of landscape patterns on ecosystem services at 1, 2, and 3 km buffer-zone scales. These findings are critical for facilitating landscape planning and regional sustainable development.

Territorial space is a multi-functional complex. The coordinated production-living-ecological space (PLES) effectively coordinates the man-land relationship, promotes regional sustainable development, and maximizes territorial space. How to build a high-quality national spatial layout and support system for development has become a hot topic of concern in all sectors of society. However, few studies have explored the coupling coordination considering the various production-living-ecological functions of land use type and its influencing factors of PLES at the county scale in China. To address the gap, based on the connotation of PLES theory, this study established a classification and evaluation system for PLES and analyzed the spatio-temporal characteristics, coupling coordination degree, spatial autocorrelation, and influencing factors of PLES in China from 2000 to 2020. The results are as follows: (1) The production space index and living space index in China showed a continuous increase tendency, while the ecological space index decreased continuously during the study period. The production space and living space were concentrated in the east of Hu Line, and the ecological space indexes in mountainous areas were significantly higher than those in plain areas during the study period. (2) The gravity centers of PLES all migrated to the west of China to different degrees during the study period. (3) From 2000 to 2020, the basically balanced category was the main coupling coordination type, and the number of seriously unbalanced categories accounted for the least. In the west of the Hu Line, the seriously unbalanced category was dominant, while in the east of the Hu Line were the moderately unbalanced categories and above. (4) During the study period, the low-low type was the main relationship type, widely distributed in western China, followed by the high-high type, mainly situated in the North China Plain, Yangtze River Delta, Pearl River Delta, Jianghan Plain, Chengdu Plain, Northeast China Plain, and some provincial capital cities. (5) Regression results showed that natural factors were the main reason restricting the coordinated development of PLES, and socioeconomic factors could effectively promote the coordinated development of PLES. Landscape pattern also significantly influenced the coordinated development of PLES, but varied greatly. The findings of this study can provide a scientific reference for the optimization of territorial space layout and the promotion of high-quality development of territorial space.

Inflammatory response contributes to brain injury after ischemia and reperfusion (I/R). Our previous literature has shown isoquercetin plays an important role in protecting against cerebral I/R injury. The present study was conducted to further investigate the effect of isoquercetin on inflammation-induced neuronal injury in I/R rats with the involvement of cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and inhibitor of NF-κB (I-κB)/nuclear factor-kappa B (NF-κB) signaling pathway mediated by Toll-like receptor 4 (TLR4) and C5a receptor 1 (C5aR1). In vivo middle cerebral artery occlusion and reperfusion (MCAO/R) rat model and in vitro oxygen-glucose deprivation and reperfusion (OGD/R) neuron model were used. MCAO/R induced neurological deficits, cell apoptosis, and release of cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in ischemic brain in rats. Simultaneously, the expression of TLR4 and C5aR1 was significantly up-regulated in both MCAO/R rats and OGD/R neurons, accompanied with the inhibition of cAMP/PKA signaling and activation of I-κB/NF-κB signaling in the cortex of MCAO/R rats. Over-expression of C5aR1 in neurons induced decrease of cell viability, exerting similar effects with OGD/R injury. Isoquercetin acted as a neuroprotective agent against I/R brain injury to suppress inflammatory response and improve cell recovery by inhibiting TLR4 and C5aR1 expression, promoting cAMP/PKA activation, and inhibiting I-κB/NF-κB activation and Caspase 3 expression. TLR4 and C5aR1 contributed to inflammation and apoptosis via activating cAMP/PKA/I-κB/NF-κB signaling during cerebral I/R, suggesting that this signaling pathway may be a potent therapeutic target in ischemic stroke. Isoquercetin was identified as a neuroprotective agent, which maybe a promising therapeutic agent used for the treatment of ischemic stroke and related diseases.

Background Tetrahymenosis caused by about ten parasitic Tetrahymena species belonging to the Phylum Ciliophora has been recognized as an emerging problem inflicting significant economic loss in aquaculture industry in the world. Increasing knowledge and identification of Tetrahymenosis are important. Methods Four parasitic Tetrahymena species were collected from eight commercially farmed fishes in Harbin, northeastern China. Specific oligonucleotide probe and fluorescence in situ hybridization staining was designed and tested. Hoechst33342 staining methods, gene sequencing and phylogenetic analyses were also conducted. Results Tetrahymena pyriformis, T. vorax, T. chironomi and T. bergeri are the four species responsible for Tetrahymenosis in various fishes in Harbin. Taxonomy, diagnosis, diversity, pathogenicity, and histopathology of Tetrahymenosis were supplemented, analyzed and summaried, based on the present and previous work. The term Tetrahymenosis is diagnosised as diseases affecting a number of fishes, crustaceans, mollus, beetle, dragonfly, salmon, slug, midge larvae and freshwater mussel species that caused by ciliates of the genus Tetrahymena which constitutes an abundant group inhabit various aquaculture and natural habitats. Improved classification of parasitic Tetrahymena was provided. Phylogeny of parasitic Tetrahymena species was studied, and an SSU-rDNA targeted oligonucleotide probe labeled with a fluorochrome was designed, and the FISH protocol was optimized for identification of Tetrahymena species, Conclusions The manifestations of histopathology in fish typically include lesions on the body surface, and affected organs include the skin, musculature, viscera, eye socket and spinal cord; masses of ciliates can be detected in copious amount of mucus and between spaces in the damaged tissues. Improved classification of parasitic Tetrahymena is provided: facultatively parasitic forms ( T. pyriformis , T. rostrate , T. bergeri and T. vorax ), facultatively free-living forms ( T. chironomi , T. corlissi, T. rotunda, T. glochidiophila and T. papula ) and parasitic forms ( T. stegomyiae and T. limacis ).The phylogenic results indicate that Tetrahymena spp. belonging to ‘borealis’ group have a greater probability to become parasitism. the method of which can be used for quick and early detection of Tetrahymenosis.

© 2020 American Chemical Society. Nanoparticles emerge to be powerful probes for the sensing of critical biomarkers because of their characteristic optical/electrochemical/magnetic properties. However, the versatility and prevalence of nanoparticle-based assays remain hampered because each kind of nanoprobe has designated properties, which requires different instruments for the readout of the signals. Herein, a versatile nanoparticle tracking analysis (NTA)-based strategy is innovatively proposed for the in vitro detection of critical biomarkers without demanding specific properties of the nanoparticles. Based on the sandwich-type immunoreaction and the duplex-specific nuclease-assisted cycling nucleic acid cleavage, the quantitative relationships are rationally built up between the level of both protein and microRNA biomarkers and the nanoparticles' number variation. Under proper conditions, NTA will provide the absolute number count and accurate size distribution of the nanoparticles in the solution phase in a real-time manner to facilely determine the level of the protein and microRNA targets. Benefiting from the intrinsic ability of NTA for grouping the nanoparticles by size and composition, the multiplexed assay of biomolecules is also achieved. Compared with the conventional nanoparticle-based biosensing systems, NTA can directly count the nanoparticles in aqueous solution, without depending on the nanoparticles' specific properties. This work remarkably improves the versatility and convenience of nanoparticle counting-based bioanalysis, inspiring the future application of NTA in biosensing.

We report follow-up observations of four transiting exoplanets, TRES-2b, HAT-P-22b, HAT-P-36b and XO-2b, as part of the Original Research By Young Twinkle Students (ORBYTS) programme. These observations were taken using the Las Cumbres Observatory Global Telescope Network's (LCOGT) robotic 0.4 m telescopes and were analysed using the HOlomon Photometric Software (HOPS). Such observations are key for ensuring accurate transit times for upcoming telescopes, such as the James Webb Space Telescope (JWST), Twinkle and Ariel, which may seek to characterise the atmospheres of these planets. The data have been uploaded to ExoClock and a significant portion of this work has been completed by secondary school students in London., Comment: Published in the Research Notes of the American Astronomical Society (RNAAS)

The booming population and accelerating urbanization in the Huaihe River Basin have sped up the land use transformation and the cultivated land fragmentation (CLF), seriously impeded the advancement of agricultural modernization, and threatened regional stability and national food security as well. The analysis of CLF degree and its spatiotemporal distribution characteristics, along with the influencing factors in the Huaihe River Basin, is of great significance for promoting the intensive and efficient utilization of cultivated land resources and maintaining food security. Previous studies lack the measurement and cause analysis of CLF in Huaihe River Basin. To bridge the gap, this study introduces Fragstats4.2 and ArcGIS10.3 to analyze the spatiotemporal characteristics of CLF in county units in the Huaihe River Basin from 2000 to 2018 through the Lorentz curve, entropy method, and spatial auto-correlation method while the causes of the spatiotemporal differentiation of CLF in the basin were explored with the help of a geographic detector. The results show that the spatial distribution of cultivated land in the Huaihe River Basin is relatively balanced, and the Gini coefficients of cultivated land from 2000 to 2018 were 0.105, 0.108, and 0.113, respectively. More than 56% of the counties in the basin have a location entropy greater than 1. the percentage of landscape, area-weighted mean patch area, patch cohesion index, and aggregation index decrease year by year while the patch density and splitting index show an upward trend. The landscape pattern of cultivated land is highly complex, and the overall fragmentation degree is increasing. The county distribution pattern of the CLF degree with random and agglomeration is generally stable. The spatiotemporal differentiation of CLF in the Huaihe River Basin is affected by multiple factors, among which the influences of the normalized difference vegetation index, per capita cultivated land area, and intensity of human activity obviously stronger than other factors, and the contribution rate of the factors reached more than 0.4. The interaction effect among the factors is stronger than that of single factor, with dual-factor enhancement and nonlinear enhancement dominating. The results of this study have important implications for optimizing the agricultural structure in the Huaihe River Basin and alleviating the CLF in important grain production areas.

The mass machine type communication (mMTC) in 5G requires the technical support of the wireless sensor network (WSN). Compared with homogeneous WSNs, heterogeneous WSNs provide more flexibility and are more in line with the reality. For heterogeneous WSNs, the use of proper routing methods can prolong the lifetime as well as the stability of the system. This paper studies an energy heterogeneous WSN, where nodes can cooperate with each other to improve the energy efficient of the network. We focus on the network routing within distributed energy-efficient clustering (DEEC) protocol, a typical networking/communication protocol for heterogeneous WSNs. First, we derive a proposition on the choice of cooperative single-hop or multi-hop modes, which gives a sufficient condition on cooperative multi-hop transmission. Furthermore, we present two lemmas, which are the conditions on the distance threshold for mode selection. Based on the above, a novel adaptive cooperative routing algorithm combined with DEEC is proposed. Simulation results show that the proposed routing algorithm outperforms the benchmark schemes and can effectively reduce the network energy consumption and prolong the network lifetime.

Tetrahymena vorax is the ciliate responsible for tetrahymenosis in the goldfish Carassius auratus. The morphology of parasitic Tetrahymena vorax isolated from C. auratus from an ornamental-fish market in Harbin was studied using living observation and silver staining methods. Carassius auratus had large, white or grey skin lesions located on various parts of the body but were most common laterally. Gills of all diseased fish were shrivelled, dark and had white ulceration. The eyes of several diseased fish had turned grey and their fins were damaged or partially blackened. Histopathological examination revealed a systemic infection, pathological features of C. auratus include presence of large, white or grey skin lesions, dark shrivelled gills, grey eyes, damaged and/or partially blackened fins and invasion of ciliate cells in epidermis and dermis, viscera and abdominal cavity. Successful systemic infection of C. auratus was achieved with T. vorax by three tested modes (scratch, immersion and injection). The results indicated that T. vorax invade C. auratus through lesions of the body surface of injured specimens.

Cervical cancer is the third most common type of cancer in women, and microRNAs play an important role in this type of cancer. The elevated expression of miR-146a is involved in the pathogenesis of cancers generally, but its role in cervical cancer has not been fully elucidated. In the present study, we assessed the expression of miR-146a in G>C polymorphisms and confirmed that the overexpression of miR-146a promoted cervical cancer cell viability. The recombinant expression plasmids pre-miR-146a-G or pre-miR-146a-C including single nucleotide polymorphisms (SNP) were successfully constructed. Pre-miR-146a-G or pre-miR-146a-C was transfected into cervical cancer cells or immortalized non-tumorigenic cells and the expression of miR-146a was evaluated by real-time PCR. The cell viability, cell-cycle analysis and apoptosis were assessed using Cell Counting Kit-8 assay (CCK-8), flow cytometry and cleaved caspase-3 protein expression, respectively. The expression of interleukin 1 receptor associated kinase 1 (IRAK1), TNF receptor-associated factor 6 (TRAF6) and cyclin D1 was assessed following the transfection with a miR-146a mimic or a negative control. The cell viability and the number of S-phase cells increased after transfection with miR-146a mimic or an IRAK1 or TRAF6 interference fragment. After transfection, IRAK1 and TRAF6 protein expression was downregulated and the expression of cyclin D1 was upregulated, however apoptosis and cleaved caspase-3 were not affected. Polymorphisms in miR-146a precursor may be linked to the expression of miR-146a and may be a potential target for cervical cancer therapy.

A novel one-transistor-n-resistors (1TnR) array architecture is demonstrated as a cost-effective solution to the sneak path problem in large-scale cross-point memory arrays. In a 1TnR array, a single transistor (1T) with a 1D channel effectively controls a number of resistive switching nonvolatile memory (NVM) cells (nR) while limiting the sneak leakage current within the 1D channel without sacrificing the device density. To maximize these benefits, a carbon nanotube FET (CNFET) is employed as the 1D selection device, due to its near-ballistic electrical transport properties even at a small device width. Experimental demonstrations of the CNFET-based 1TnR concept are presented with two promising resistive switching NVM candidates: 1) resistive random access memory (RRAM) and 2) phase-change memory (PCM). Here, we report that the integrated bipolar Al2O3-based RRAM consumes programming energies as low as 0.1–7 pJ per bit and has a high programming endurance of up to $10^{6}\vphantom {\sum ^{R^{R}}}$ cycles. The 1TnR RRAM cell also has self-compliance characteristics, because the semiconducting carbon nanotube (CNT) that serves as the bottom electrode limits the device current. The unipolar PCM cells integrated with CNFETs show uniform electrical characteristics with high ON-/OFF-resistance ratios of >10. Owing to the extremely small contact area between the phase change material, Ge2Sb2Te5, and the CNT, remarkably low programming currents of $ are achieved.

The impact of wordline/bitline metal wire scaling on the write/read performance, energy consumption, speed, and reliability of the cross-point memory array is quantitatively studied for technology nodes down to single-digit nm. The impending resistivity increase in the Cu wires is found to cause significant decrease of both write and read window margins at the regime when electron surface scattering and grain boundary scattering are substantial. At deeply-scaled device dimensions, the wire energy dissipation and wire latency become comparable to or even exceed the intrinsic values of memory cells. The large current density flowing through the wordlines/bitlines raises additional reliability concerns for the cross-point memory array. All these issues are exacerbated at smaller memory resistance values and larger memory array sizes. They thereby impose strict constraints on the memory device design and preclude the realization of large-scale cross-point memory array with minimum feature sizes beyond the 10 nm node. A rethink in the design methodology of cross-point memory to incorporate and mitigate the scaling effects of wordline/bitline is necessary. Possible solutions include the use of memory wires with better conductivity and scalability, memory arrays with smaller partition sizes, and memory elements with larger resistance values and resistance ratios.

In this paper, we employed Ramen spectroscopy to monitor oxygen movement at the electrode/oxide interface by inserting single-layer graphene (SLG). Raman area mapping and single-point measurements show noticeable changes in the D-band, G-band, and 2D-band signals of the SLG during consecutive electrical programming repeated for nine cycles. In addition, the inserted SLG enables the reduction of RESET current by 22 times and programming power consumption by 47 times. Collectively, our results show that monitoring the oxygen movement by Raman spectroscopy for a resistive random access memory (RRAM) is made possible by inserting a single-layer graphene at electrode/oxide interface. This may open up an important analysis tool for investigation of switching mechanism of RRAM.

Solid-state memory technology is undergoing a renaissance of new materials and novel device concepts for higher scalability as the mainstream technology, i.e., Flash, is approaching physical limits. Emerging memory technologies, which have unique characteristics not available in Flash, are leading transformations in the design of the memory hierarchy. Phase change memory (PCM) is a promising candidate for the next-generation nonvolatile-memory technology. It has been extensively studied for its electrical properties and material scalability. Yet, questions remain unanswered as to what extent a functional PCM cell can be ultimately scaled to and what properties a PCM cell has at the single-digit nanometer scale. In this paper, we demonstrated a fully functional cross-point PCM cell working close to its ultimate size-scaling limit by using carbon nanotubes (CNTs) as the memory electrode. The utilization of CNT electrode brings the lithography-independent critical dimension down to 1.2 nm and contributes to a large reduction of the reset programming current to 1.4 μA and the programming energy to 210 fJ using a 10 ns reset pulse. Measured electrical characteristics validate the advantage of further device area scaling on reducing the programming current of PCM cells and confirm the potential viability of a highly scaled ultradense PCM array down to the bottom electrode contact area that corresponds to a 1.8 nm node technology.