Karst watershed refers to the total range of surface and underground recharge areas of rivers (including subterranean rivers and surface rivers) in karst areas. Karst water resources, as the primary ...source of domestic water supply in southwest China, are vital for the social and economic development of these regions. It is greatly significant to establish a high-precision hydrological model of karst watershed for guiding water resources management in karst areas. Choosing the Daotian river basin in the Wumeng Mountains of Southwest China as the study area, this paper proposed a method for simplifying karst subterranean rivers into surface rivers by modifying the digital elevation model (DEM) based on a field survey and tracer test. This method aims to solve the inconsistency between the topographical drainage divides and actual catchment boundaries in karst areas. The Soil and Water Assessment Tool (SWAT) model was modified by replacing the single-reservoir model in the groundwater module with a three-reservoir model to depict the constraints of multiple media on groundwater discharge in the karst system. The results show that the catchment areas beyond topographic watershed were effectively identified after simplifying subterranean rivers to surface rivers based on the modified DEM data, which ensured the accuracy of the basic model. For the calibration and two validation periods, the Nash–Sutcliffe efficiencies (NSE) of the modified SWAT model were 0.87, 0.83, and 0.85, respectively, and R2 were 0.88, 0.84, and 0.86, respectively. The NSE of the modified SWAT model was 0.09 higher than that of the original SWAT model in simulating baseflow, which effectively improved the simulation accuracy of daily runoff. In addition, the modified SWAT model had a lower uncertainty within the same parameter ranges than the original one. Therefore, the modified SWAT model is more applicable to karst watersheds.
The quality of global cropland products could affect our understanding of the impacts of cropland reclamation on global changes. With the advancement of remote sensing technology, several global land ...cover products and synergistic datasets have been developed in recent decades. However, there are still some disagreements among the global cropland datasets. In this paper, we proposed a new synergistic method that integrates the reliability of spatial distribution and cropland fraction on a pixel scale, and developed a modern (around 2000 C.E.) fractional cropland dataset with a 1 km × 1 km spatial resolution on the basis of the spatial consistency of cropland reclamation intensity derived from multi-sets of global land cover products. The main conclusions are shown as follows: (1) The accuracy of spatial distribution assessed by validation samples in this synergistic dataset reaches 87.6%, and the dataset also has a moderate amount of cropland pixels when compared with other products. (2) The reliability of cropland fraction on the pixel scale had been highly improved, and most cropland pixel has a higher fraction (over 90%) in this dataset. The “L” shape of the histogram of pixel numbers with different reclamation intensities is reasonable because it is consistent with the up-scaling results derived from satellite-derived products with high spatial resolutions and the expert knowledge on cultivation. (3) The cropland areas in this non-calibrated result are generally closer to that of FAOSTAT on scales from global to national when compared to other non-calibrated synergistic datasets and original satellite-derived products. (4) The reliability of the synergistic result developed by this method might be decreased to some degree in the regions with high discrepancies among the original multi-sets of cropland datasets.
Abstract
Black hole feedback has been widely implemented as the key recipe to quench star formation in massive galaxies in modern semianalytic models and hydrodynamical simulations. As the ...theoretical details surrounding the accretion and feedback of black holes continue to be refined, various feedback models have been implemented across simulations, with notable differences in their outcomes. Yet, most of these simulations have successfully reproduced some observations, such as the stellar mass function and star formation rate density in the local universe. We use the recent observation of the change in the neutral hydrogen gas mass (including both H
2
and H I) with the star formation rate of massive central disk galaxies as a critical constraint of black hole feedback models across several simulations. We find that the predictions of IllustrisTNG agree with the observations much better than the other models tested in this work. This favors IllustrisTNG’s treatment of active galactic nuclei (AGN)—where kinetic winds are driven by black holes at low accretion rates—as more plausible among those we test. In turn, this also indirectly supports the idea that the massive central disk galaxy population in the local universe was likely quenched by AGN feedback.
To screen lung adenocarcinoma (LUAC)-specific cell-cycle-related genes (CCRGs) and develop a prognostic signature for patients with LUAC.
The GSE68465, GSE42127, and GSE30219 data sets were ...downloaded from the GEO database. Single-sample gene set enrichment analysis was used to calculate the cell cycle enrichment of each sample in GSE68465 to identify CCRGs in LUAC. The differential CCRGs compared with LUAC data from The Cancer Genome Atlas were determined. The genetic data from GSE68465 were divided into an internal training group and a test group at a ratio of 1:1, and GSE42127 and GSE30219 were defined as external test groups. In addition, we combined LASSO (least absolute shrinkage and selection operator) and Cox regression analysis with the clinical information of the internal training group to construct a CCRG risk scoring model. Samples were divided into high- and low-risk groups according to the resulting risk values, and internal and external test sets were used to prove the validity of the signature. A nomogram evaluation model was used to predict prognosis. The CPTAC and HPA databases were chosen to verify the protein expression of CCRGs.
We identified 10 LUAC-specific CCRGs (PKMYT1, ETF1, ECT2, BUB1B, RECQL4, TFRC, COCH, TUBB2B, PITX1, and CDC6) and constructed a model using the internal training group. Based on this model, LUAC patients were divided into high- and low-risk groups for further validation. Time-dependent receiver operating characteristic and Cox regression analyses suggested that the signature could precisely predict the prognosis of LUAC patients. Results obtained with CPTAC, HPA, and IHC supported significant dysregulation of these CCRGs in LUAC tissues.
This prognostic prediction signature based on CCRGs could help to evaluate the prognosis of LUAC patients. The 10 LUAC-specific CCRGs could be used as prognostic markers of LUAC.
Hyperbolicity and Chordality of a Graph Wu, Yaokun; Zhang, Chengpeng
The Electronic journal of combinatorics,
02/2011, Letnik:
18, Številka:
1
Journal Article
Recenzirano
Let $G$ be a connected graph with the usual shortest-path metric $d$. The graph $G$ is $\delta$-hyperbolic provided for any vertices $x,y,u,v$ in it, the two larger of the three sums ...$d(u,v)+d(x,y),d(u,x)+d(v,y)$ and $d(u,y)+d(v,x)$ differ by at most $2\delta.$ The graph $G$ is $k$-chordal provided it has no induced cycle of length greater than $k.$ Brinkmann, Koolen and Moulton find that every $3$-chordal graph is $1$-hyperbolic and that graph is not $\frac{1}{2}$-hyperbolic if and only if it contains one of two special graphs as an isometric subgraph. For every $k\geq 4,$ we show that a $k$-chordal graph must be $\frac{\lfloor\frac{k}{2}\rfloor}{2}$-hyperbolic and there does exist a $k$-chordal graph which is not $\frac{\lfloor \frac{k-2}{2}\rfloor}{2}$-hyperbolic. Moreover, we prove that a $5$-chordal graph is $\frac{1}{2}$-hyperbolic if and only if it does not contain any of a list of five special graphs as an isometric subgraph.
The multiscale hierarchical structures inspired by moth's compound eyes offer multifunctional properties in optoelectronic devices. However, it is still a major challenge to fabricate these ...hierarchical structures on large-area substrates using a simple and cost-effective technique. The roll-to-roll ultraviolet nanoimprint lithography (R2R UV-NIL) technique provides a solution for the continuous fabrication of multiscale compound eyes arrays due to its high-speed, large-area, high-resolution, and high-throughput. In this paper, the R2R UV-NIL technique was used to fabricate the multiscale compound eyes arrays on the PET substrate. The mold used in the R2R UV-NIL process was acquired by anodic aluminum oxide process and then the multiscale compound eyes arrays were directly obtained via one-step R2R imprinting. The obtained multiscale compound eyes arrays exhibit excellent antireflective performance within the wavelength 400-800 nm. Besides, the compound eyes arrays also equip the surface of the microlens with excellent hydrophobic characteristics. These multifunctional properties enable the multiscale compound eyes arrays to retain their superior optical properties in real-time environmental conditions. This report can provide a beneficial direction for the continuous production and widespread applications of the multiscale compound eyes arrays.
Gastric cancer (GC) is one of the main causes of cancer-related death. Lysine acetyltransferases 2 A (KAT2A) is a succinyltransferase that plays an essential role in cancer development. The pyruvate ...kinase M2 (PKM2) is a glycolysis rate-limiting enzyme that mediates the glycolysis of cancers. This study aimed to explore the effects and mechanism of KAT2A in GC progression. The effects of biological behaviors of GC cells were evaluated by MTT, colony formation and seahorse assays. The succinylation modification was assessed by immunoprecipitation (IP). The interaction between proteins were detected by Co-IP and immunofluorescence. A pyruvate kinase activity detection kit was used to evaluate the activity of PKM2. Western blot was performed to detect the expression and oligomerization of protein. Herein, we confirmed that KAT2A was highly expressed in GC tissues and was associated with a poor prognosis. Function studies showed that knockdown of KAT2A inhibited cell proliferation and glycolytic metabolism of GC. Mechanistically, KAT2A could directly interacted with PKM2 and KAT2A silencing inhibited the succinylation of PKM2 at K475 site. In addition, the succinylation of PKM2 altered its activity rather than its protein levels. Rescue experiments showed that KAT2A promoted GC cell growth, glycolysis, and tumor growth by promoting PKM2 K475 succinylation. Taken together, KAT2A promotes the succinylation of PKM2 at K475 to inhibit PKM2 activity, thus promotes the progression of GC. Therefore, targeting KATA2 and PKM2 may provide novel strategies for the treatment of GC.
Society and consumers are increasingly concerned about food safety and the sustainability of food production systems. A significant amount of by-products and discards are generated during the ...processing of aquatic animals, which still needs to be fully utilized by the food industry. The management and sustainable use of these resources are essential to avoiding environmental pollution and resource waste. These by-products are rich in biologically active proteins, which can be converted into peptides by enzymatic hydrolysis or fermentation treatment. Therefore, exploring the extraction of collagen peptides from these by-products using an enzymatic hydrolysis technology has attracted a wide range of attention from numerous researchers. Collagen peptides have been found to possess multiple biological activities, including antioxidant, anticancer, antitumor, hypotensive, hypoglycemic, and anti-inflammatory properties. These properties can enhance the physiological functions of organisms and make collagen peptides useful as ingredients in food, pharmaceuticals, or cosmetics. This paper reviews the general methods for extracting collagen peptides from various processing by-products of aquatic animals, including fish skin, scales, bones, and offal. It also summarizes the functional activities of collagen peptides as well as their applications.
We present a submillimeter continuum survey ("SCUBA2 High rEdshift bRight quasaR surveY," hereafter SHERRY) of 54 high-redshift quasars at 5.6 < z < 6.9 with quasar bolometric luminosities in the ...range of (0.2-5) × 1014 L , using the Submillimetre Common-User Bolometer Array-2 (SCUBA2) on the James Clerk Maxwell Telescope. About 30% (16/54) of the sources are detected with a typical 850 m rms sensitivity of 1.2 mJy beam−1 (S ,850 m = 4-5 mJy, at >3.5 ). The new SHERRY detections indicate far-infrared (FIR) luminosities of 3.5 × 1012 to 1.4 × 1013 L , implying extreme star formation rates of 90-1060 M yr−1 in the quasar host galaxies. Compared with z = 2-5 samples, the FIR-luminous quasars (LFIR > 1013 L ) are rarer at z ∼ 6. The optical/near-infrared spectra of these objects show that 11% (6/54) of the sources have weak Ly emission-line features, which may relate to different subphases of the central active galactic nuclei (AGNs). Our SCUBA2 survey confirms the trend reported in the literature that quasars with submillimeter detections tend to have weaker ultraviolet (UV) emission lines compared to quasars with nondetections. The connection between weak UV quasar line emission and bright dust continuum emission powered by massive star formation may suggest an early phase of AGN-galaxy evolution, in which the broad-line region is starting to develop slowly or is shielded from the central ionization source, and has unusual properties such as weak-line features or bright FIR emission.
Broadband antireflection is essential for improving the photocurrent generation of photovoltaic modules or the enhancement of visibility in optical devices. The moth-eye nanostructure is one of the ...most promising structures with potential for commercialization in the near future and roll-to-roll ultraviolet nanoimprint lithography (R2R UV-NIL) technique provides a solution for the commercialization due to its high speed, large area, high resolution, and high throughput. In this study, the anodic aluminum oxide (AAO) mold is used to produce the moth-eye nanostructure arrays upon a flexible polyethylene terephthalate substrate combining with R2R UV-NIL process, which provides a solution for continuous production of moth-eye nanostructure arrays cheaply. In addition, the influence of mold parameters and process parameters on the forming quality were investigated, respectively. The influence of process parameters was investigated by using the one-variable-at-a-time method, including feeding speed, imprinting pressure, and mold temperature. The qualitative and quantitative height evaluation for the moth-eye nanostructure arrays were carried out based on the atomic force microscope images. As a result, the feasibility is verified to produce moth-eye nanostructure arrays continuously with AAO mold and R2R UV-NIL technique. A rapid feeding speed of 20 m/min was possible to produce good moth-eye nanostructure arrays with mold 1, which were 300 nm in diameter, 300 nm in height. However, different forming results were observed as the mold parameters decreased including unsatisfactory demolding phenomenon and incomplete filling phenomenon. The incomplete filling phenomenon was improved to a certain extent by changing the process parameters and higher forming height was accomplished with lower feeding speed, higher imprinting pressure, and higher mold temperature. This research is beneficial to provide a direction for the industrial production of the moth-eye nanostructure arrays.
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