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Future wireless networks require high throughput and energy efficiency. This paper studies using Reinforcement Learning (RL) to do transmission rate and power control for maximizing a joint reward function consisting of both throughput and energy consumption. We design the system state to include factors that reflect packet queue length, interference from other nodes, quality of the wireless channel, battery status, etc. The reward function is normalized and does not involve unit conversion. It can be used to train three different types of agents: throughput-critical, energy-critical, and throughput and energy balanced. Using the NS-3 network simulation software, we implement and train these agents in an 802.11ac network with the presence of a jammer. We then test the agents with two jamming nodes interfering with the packets received at the receiver. We compare the performance of our RL optimal policies with the popular Minstrel rate adaptation algorithm: our approach can achieve (i) higher throughput when using the throughput-critical reward function; (ii) lower energy consumption when using the energy-critical reward function; and (iii) higher throughput and slightly higher energy when using the throughput and energy balanced reward function. Although our discussion is focused on 802.11ac networks, our method is readily applicable to other types of wireless networks., Comment: Published in International Telecommunication Union, Journal on Future and Evolving Technologies (ITU J-FET) 2022

Corneal transplantation is an effective treatment for reconstructing injured corneas but is very limited due to insufficient donors, which has led to a growing demand for development of artificial corneal substitutes (ACSs). Collagen is a potential building block for ACS fabrication, whereas technically there are limited capabilities to control the collagen assembly for creating highly transparent collagen ACSs. Here, we report an electro-assembly technique to kinetically control collagen assembly on the nanoscale that allows the yielding collagen ACSs with structure determined superior optics. Structurally, the kinetically electro-assembled collagen (KEA-Col) is composed of partially aligned microfibrils (∼10 nm in diameter) with compacted lamellar organization. Optical analysis reveals that such microstructure is directly responsible for its optimal light transmittance by reducing light scattering. Moreover, this method allows the creation of complex three-dimensional geometries and thus is convenient to customize collagen ACSs with specific curvatures to meet refractive power requirements. Available properties (e.g., optics and mechanics) of cross-linked KEA-Cols were studied to meet the clinical requirement as ACSs, and

Even in a single society, different people may have different opinions on fairness, of which a few may be considered to be legitimate. In income redistribution, people will choose one of them to claim that a redistribution is fair, considering their own interests. Underprivileged would demand equal distribution, while privileged people would assert the present distribution is so fair that no distribution is necessary. In short, though they may refer only to how the present income distribution is determined to support their opinions on fairness, people take account of what concept of fairness is favorable to them in their mind. Consider purely, eliminating the effect of how to get the initial income such as effort ,talent and luck and something else, we just focus on even subjects get the money occasionally, they still respect the received money, and lead to an effect to their fairness consideration, then show an different redistribution behavior. We have already conduct some experiments from 2018 to 2019. Due to the Covid-19, it's hard to recruit subjects to attend experiments in experimental Lab. But now for the policies and environment of Covid-19 is changed. It's possible for us to conduct the Lab experiments. Therefore, we would like to do the further researches on the same research problem. Forever, check wether peoples' options have changed after the experience of Covid-19.

Partially substituting Pb2+ with an appropriate amount of Sn2+ simultaneously reduces the bandgap and improves the quality and morphology of a CsPbBr3 perovskite film.

Inorganic CsPbBr

Hierarchical porous carbon materials with high surface area are facilely prepared by directly carbonizing carex meyeriana without any extra activation procedure. The as-prepared porous carbon samples possess high Brunauer–Emmett–Teller (BET) surface areas (in the ~ 518–742 m2 g−1 range) and unique hierarchical porous structure containing macropore channels and mesopores and micropores developed in the wall of macropores. These intriguing characteristics make the as-prepared hierarchical porous carbon samples a promising electrode material for supercapacitors. The capacitive performance was measured in the three-electrode system with 6 M KOH electrolyte. The hierarchical porous carbon prepared at the carbonization temperature of 1000 °C presents a high specific capacitance of 178.6 F g−1 at a current density of 0.5 A g−1, a good rate performance ( about 65.2% retention ratio at the current density of 20 A g−1), and an excellent cycling stability (no obvious performance fading after 10,000 cycles). In addition, the fabricated two-electrode device achieves an energy density of 4.33 Wh kg−1 at a high power density of 5 kW kg−1. These results provide a green and facile method to synthesize the electrode material from biomass for high-performance supercapacitors.

To explore the water resistance properties of lime soil ground, the physical and mechanical properties of lime soil with 5%, 10%, 15% and 20% lime content after long-term water immersion were studied by conducting unconfined compressive tests, density tests and water absorption tests. The results show that the stress–strain relationship curves of the lime soil during immersion are of the strain-softening type. The curves are multistage and nonlinear with evident peak values, and the lime soil achieves ductility and toughness with an increase in immersion time. The failure modes of the lime soil samples mainly include single slope shear failures, brittle splitting failures and conjugate shear failures, which are mainly affected by the lime content and immersion time. The strength of the lime soil decreases sharply in a short time while interacting with water. The strength slowly increases to 50.07–69.15% of the initial strength after immersion for a long time, i.e., still far less than the initial strength without immersion. Under long-term immersion, the water absorption of the lime soil increases gradually at the initial stage of immersion and then increases to a stable value of 16.76–21.67%. The change law of the wet density is essentially controlled by the water absorption. The strength of lime soil decreases significantly, and the water resistance capacity is poor after soaking; lime soil with 15% lime content has better engineering properties. It is recommended to apply lime soil with 15% lime content in practical engineering with a volume ratio of lime to soil of 3:7 and to avoid using lime soil materials in immersed or other dry-humid environments.

Based on the pavement temperature observation data of the transportation meteorological stations along the Xianyang Airport Expressway, China, as well as the datasets of precipitation and sunshine hours obtained from the nearby weather stations, the variation characteristics of local pavement temperatures are investigated for winter in this study. Results indicate that during the daytime, the pavement temperatures are always higher on sunny and cloudy days than those on rainy and snowy days, while during the nighttime, the temperatures on sunny and cloudy days are higher than those on the days with freezing rain and snow, and with the temperatures on rainy and snowy days without icing being further higher. In general, the pavement temperatures in winter features significant periodic oscillations with cycles of roughly 24 h, 12 h, 8 h, 6 h, 5 h and 4 h, which differ slightly at different times for different stations. Moreover, the nowcasting experiments on the local pavement temperatures are also carried out using a regression model via extracting the corresponding periodic features. It shows the mean absolute errors of about 0.6 °C, 1.2 °C, and 1.5 °C for lead times of 1 h, 2 h, and 3 h, respectively. The nowcasting skills are higher on rainy and snowy days, while are inferior on sunny days. For nowcasting cases initialized at nighttime (daytime), the mean absolute errors are 0.4 °C (0.7 °C) and 0.9 °C (1.4 °C) for lead times of 1 h and 2 h. Examinations suggest that the nowcasting system could be well utilized in plain areas of China, whereas it shows relatively larger biases in plateau areas with complex terrain.

Collagen is a biological building block that is hierarchically assembled into diverse morphological structures that, in some cases, is dynamically adaptive in response to external cues and in other cases forms static terminal structures. Technically, there is limited capabilities to guide the emergence of collagen’s hierarchical organization to recapitulate the richness of biological structure and function. Here, we report an electro-assembly pathway to create a dynamically adaptive intermediate molten fibril state for collagen. Structurally, this intermediate state is composed of partially aligned and reversibly associating fibrils with limited hierarchical structure. These molten fibrils can be reversibly reconfigured to offer dynamic properties such as stimuli-stiffening, stimuli-contracting, self-healing, and self-shaping. Also, molten fibrils can be guided to further assemble to recapitulate the characteristic hierarchical structural features of native collagen (e.g., aligned fibers with D-banding). We envision that the electro-assembly of collagen fibrils will provide previously unidentified opportunities for tailored collagen-based biomedical materials.

Additional file 1. Supplementary Material.

Hierarchical porous carbon arrays (HPCAs) are facilely produced by directly carbonizing Carex meyeriana through a self-activated and self-template process. The morphology analysis and nitrogen sorption measurements reveal that the obtained HPCAs have a large specific surface area and unique hierarchical pore structure comprising macropore channel arrays and micropores and mesopores developed on the wall of macropore channels. The HPCA electrodes are subsequently prepared by depositing HPCAs to the fluorine-doped tin oxide conductive substrate. Electrochemical tests demonstrate that the HPCA electrode shows a superior electrocatalytic activity for the regeneration of the I–/I3– electrolyte. The superior electrocatalytic activity of HPCA electrodes is mainly due to the combined effect of unique hierarchical pore architecture and large surface area, which facilitates the electrolyte diffusion and provides the abundant effective electrocatalytic active sites. Under 1 sun illumination, the HPCA electrode-based dye-sensitized solar cell displays a gratifying conversion efficiency of 6.45%, which is close to that based on commonly used Pt electrodes.

To meet the increased performance and cost requirements of commercial supercapacitor, a N and O self-doped hierarchical porous carbon is fabricated via a green and simple self-activation route utilizing leaves of wild hollyhock as raw materials. Comparing to commercial activated carbon, the reported material exhibits some marked merits, such as simple and green fabrication process, low cost, and superior capacitance performance. The specific surface area of the obtained N and O co-doped hierarchical porous carbon arrives 954 m2 g−1, and the content of the self-doped nitrogen and oxygen reaches 2.64 at.% and 7.38 at.%, respectively. The specific capacitance of the obtained material reaches 226 F g−1 while the specific capacitance of the symmetric supercapacitor arrives 47.3 F g−1. Meanwhile, more than 90.3% of initial specific capacitance is kept under a current density of 20 A g−1, and no arresting degradation is observed for capacitance after 5000 times cycle, perfectly demonstrating the excellent cycle and rate capability of the obtained material. The obtained N and O co-doped hierarchical porous carbon are expected to be an ideal substitution for commercial activated carbon.

The construction of a biomaterial matrix with biological properties is of great importance to developing functional materials for clinical use. However, the site-specific immobilization of growth factors to endow materials with bioactivities has been a challenge to date. Considering the wide existence of glycosylation in mammalian proteins or recombinant proteins, we establish a bioaffinity-based protein immobilization strategy (bioanchoring method) utilizing the native sugar-lectin interaction between concanavalin A (Con A) and the oligosaccharide chain on glycosylated bone morphogenetic protein-2 (GBMP-2). The interaction realizes the site-specific immobilization of GBMP-2 to a substrate modified with Con A while preserving its bioactivity in a sustained and highly efficient way, as evidenced by its enhanced ability to induce osteodifferentiation compared with that of the soluble GBMP-2. Moreover, the surface with Con A-bioanchored GBMP-2 can be reused to stimulate multiple batches of C2C12 cells to differentiate almost to the same degree. Even after 4 month storage at 4 °C in phosphate-buffered saline (PBS), the Con A-bioanchored GBMP-2 still maintains the bioactivity to stimulate the differentiation of C2C12 cells. Furthermore, the ectopic ossification test proves the in vivo bioactivity of bioanchored GBMP-2. Overall, our results demonstrate that the tag-free and site (i.e., sugar chain)-specific protein immobilization strategy represents a simple and generic alternative, which is promising to apply for other glycoprotein immobilization and application. It should be noted that although the lectin we utilized can only bind to d-mannose/d-glucose, the diversity of the lectin family assures that a specific lectin could be offered for other sugar types, thus expanding the applicable scope further.

Microbial disinfection associated with medical device surfaces has been an increasing need, and surface modification strategies such as antibacterial coatings have gained great interest. Here, we report the development of polydopamine-ferrocene (PDA-Fc)-functionalized TiO2 nanorods (Ti-Nd-PDA-Fc) as a context-dependent antibacterial system on implant to combat bacterial infection and hinder biofilm formation. In this work, two synergistic antimicrobial mechanisms of the PDA-Fc coating are proposed. First, the PDA-Fc coating is redox-active and can be locally activated to release antibacterial reactive oxygen species (ROS), especially ·OH in response to the acidic microenvironment induced by bacteria colonization and host immune responses. The results demonstrate that redox-based antimicrobial activity of Ti-Nd-PDA-Fc offers antibacterial efficacy of over 95 and 92% against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), respectively. Second, the photothermal effect of PDA can enhance the antibacterial capability upon near-infrared (NIR) irradiation, with over 99% killing efficacy against MRSA and E. coli, and even suppress the formation of biofilm through both localized hyperthermia and enhanced ·OH generation. Additionally, Ti-Nd-PDA-Fc is biocompatible when tested with model pre-osteoblast MC-3T3 E1 cells and promotes cell adhesion and spreading presumably due to its nanotopographical features. The MRSA-infected wound model also indicates that Ti-Nd-PDA-Fc with NIR irradiation can effectively eliminate bacterial infection and suppress host inflammatory responses. We believe that this study demonstrates a simple means to create biocompatible redox-active coatings that confer context-dependent antibacterial activities to implant surfaces.

Diffuse large B-cell lymphoma (DLBCL) is the most aggressive non-Hodgkin lymphoma (NHL), accounting for about 31% of the newly diagnosed NHL worldwide. Although approximately 60% of patients who initially received a standard R-CHOP treatment likely have a 3-year event-free survival, many patients become refractory or relapsed due to the genetic heterogeneity of this malignancy. Hence, new treatment strategies are urgently needed. MEF2C, a member of the MEF2 transcription factor family gene, plays great important roles involved in the development of various tissues and the pathogenesis of lymphoma. However, the exact functions and molecular mechanisms of MEF2C in DLBCL are not fully investigated. By Sanger sequencing, we identified a novel point mutation of MEF2C at the p.N389 site in DLBCL patient, which was further validated by several DLBCL cell lines. Intriguingly, we found that the p.N389S mutation did not influence MEF2C expression, protein stability, and subcellular distribution, but enhanced its transcriptional activity. Furthermore, we demonstrated that MEF2C p.N389S mutation promotes DLBCL cell proliferation, cellular adhesion, and tumor formation in nude mice. On mechanism, our data revealed that MEF2C p.N389S mutation increases c-JUN expression, and c-JUN regulation mediated the oncogenic function of MEF2C p.N389S mutation on DLBCL cells. Our finding may provide a significant insight into the DLBCL and a compelling therapy target for this disease treatment.

Drug delivery systems developed from zwitterionic polymers have intriguing antifouling properties. Combining these with stimuli-responsiveness, we fabricated a new type of zwitterionic nanogel with dual redox-labile properties by copolymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and a diselenide bond-containing crosslinker through reflux precipitation polymerization. Poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-based nanogels show high protein adsorption resistibility and colloidal stability at high salt concentrations. By incorporation of diselenide bonds into polymer networks, the nanogels are endowed with unique dual redox-labile properties that lead to their efficient degradation into short polymers either in a reducing environment (GSH) or in an oxidative environment (H2O2). Nanogels loaded with anticancer drugs (doxorubicin, DOX) display a finely controlled release behavior and low leakage of DOX under physiological conditions (15.0% in 24 h), but rapid and sufficient release under reducing conditions (88.3% in 24 h) or under oxidative conditions (82.2% in 24 h). Cell viability assays reveal that the blank nanogels have no cytotoxicity within a wide concentration range, while DOX-loaded nanogels present a significant inhibitive effect against tumor cells.

Carbon electrode-based all-inorganic perovskite solar cells (PSCs) without hole-transport materials are attracting extensive interest due to their low cost, simple fabrication process, and high stability. Nevertheless, the conversion efficiency of carbon electrode-based PSCs is far from satisfactory owing to serious charge recombination at the inorganic perovskite/carbon interface, which mainly derives from the mismatched energy level between the inorganic perovskite film and carbon layer. Herein, a hydrophobic CuSCN film is introduced into carbon electrode-based CsPbIBr2 all-inorganic PSCs as a multifunctional interlayer between the CsPbIBr2 perovskite film and carbon electrode to form a favorable interfacial energy level alignment and protect the CsPbIBr2 perovskite from ambient moisture. It is found that introducing a CuSCN interlayer can not only enhance the hole extraction and suppress the charge recombination in carbon electrode-based CsPbIBr2 all-inorganic PSCs, but also improve the stability of the cell. Moreover, the very strong interaction between SCN−1 and Pb2+ remarkably reduces the surface defects of the CsPbIBr2 perovskite film. Consequently, the device with the CuSCN interlayer displays an improved power conversion efficiency of 7.30% in comparison with 5.19% for the device without the CuSCN interlayer and an excellent long-term stability under the ambient conditions.

Acute myeloid leukemia is an aggressive myeloid malignancy, characterized by rapid cellular proliferation and generally high mortality. Due to the lack of a complete understanding of AML, its clinical outcomes are still not satisfactory. In this study, we examined the function of the long non-coding RNA-HLA complex P5 (HCP5) on AML by analyzing the clinical samples, TCGA data, and by shRNA-mediated HCP5 deficiency in vitro. Our results showed that HCP5 is highly expressed in AML and is positive associated with poor prognosis, and HCP5 knockdown was significantly suppressing AML cell line proliferation and inducing G1/S arrest in vitro. In mechanism, the proteasome subunit beta type 8 (PSMB8) expression was dramatically inhibited in HCP5 knockdown cells while increased in HCP5 overexpression cells. PSMB8 was also highly expressed in AML and with poor prognosis. Furthermore, HCP5 regulates PI3K/AKT pathway activation depending on PSMB8. Our results showed a promoting function of HCP5 on AML and may provide a compelling biomarker and therapy target for AML.

The contamination of chronic wound with bacteria especially methicillin-resistant Staphylococcus aureus (MRSA) is considered as the major factor interferencing normal wound healing. There still remain great challenges in developing safe and effective wound dressings with wide-spectrum antibacterial functions. Alginate hydrogel is a common dressing for wound treatment. Copper is one of the trace elements in human body with inherent antibacterial activity. Traditional methods for preparing a structure-controlled copper-alginate antibacterial matrix are difficult however, due to the fast and uncontrolled gelation between alginate and metal ions. In this work, we report an electrodeposition method for rapid fabrication of copper cross-linked alginate antibacterial films (Cu2+-Alg) with controlled structure and copper content, which is relied on an electrical signal controlled release of copper ions from the reaction of insoluble salt Cu2(OH)2CO3 and the generated protons via water electrolysis on anode. The results prove that the physical structure and chemical composition of the electrodeposited Cu2+-Alg films can be continuously modulated by the imposed charges during electrodeposition. In vitro tests demonstrate the film has Cu2+ content-dependent bactericidal activities. Film’s cytocompatibility is well controlled by the imposed charges for Cu2+-Alg fabrication. The MRSA infected wound model in vivo also indicates that Cu2+-Alg film can effectively eliminate bacterial infection and suppress host inflammatory responses. We believe this study demonstrates a convenient and controllable strategy to fabricate alginate antibacterial dressings with potential applications for infected wound treatment. More broadly, our work reveals electrodeposition is a general and simple platform to design alginate films with versatile functions.

Pathogenic bacteria and antibiotic resistance genes (ARGs) in bioaerosols are major threats to human health. In this study, the microbial community structure and ARG distribution characteristics of airborne bacteria in total suspended particulates (TSP) and PM2.5 were investigated under different air quality levels in Xinxiang, Central China. The results revealed that with the deterioration of air quality, the concentrations of airborne bacteria in both TSP and PM2.5 decreased; however, the relative amounts of pathogenic bacteria increased. The predominant genera in pathogenic bacteria of Bacillus, Sphingomonas, Corynebacterium, Rhodococcus, and Staphylococcus were identified in both TSP and PM2.5. Although the airborne bacteria concentrations and absolute abundances of ARGs in TSP were higher than those in PM2.5 under identical air quality conditions, the bacterial community structure and relative amounts of pathogenic bacteria were similar. In addition, the relationship between environmental factors of ions, metal elements, and meteorological parameters and the community structures of airborne bacteria and pathogenic bacteria were also analyzed. The effects of soluble ions and metal elements on several dominant genera of total bacteria and pathogenic bacteria differed, probably due to the strong tolerance of pathogenic bacteria to harsh atmospheric environments Different subtypes of ARGs showed various distribution characteristics with variations in air quality. The deterioration of air quality can inhibit the dissemination of ARGs, as the minimum values of all ARGs and class 1 integrase intI1 were observed under Severely Polluted conditions. This study provides a comprehensive understanding of the effect of air pollution levels on the airborne bacteria community composition and ARG distribution.

Janus porous biomaterials are gaining increasing attention and there are considerable efforts to develop simple, rapid, and scalable methods capable of tuning micro- and macro-structures. Here, a single-step electro-fabrication method to create a Janus porous film by the electrodeposition of the amino-polysaccharide chitosan is reported. Specifically, a Janus structure emerges spontaneously when electrodeposition is performed at sub-ambient temperature (0-5 °C). Sub-ambient temperature electrodeposition experiments show that: a Janus microstructure emerges (potentially as the result of a subtle alteration of the intermolecular interactions responsible for self-assembly); important microstructural features (pore size, porosity, and thicknesses) can be tuned by conditions; and this method is readily scalable (vs serial printing) and can yield complex tubular structures with Janus faces. In vitro studies demonstrate anisotropic cell guidance, and in vivo studies using a rat calvarial defect model further confirm the beneficial features of such Janus porous film for guided bone regeneration. In summary, these results further demonstrate that electro-fabrication provides a simple and scalable platform technology for the controlled functional structures of soft matter for applications in regenerative medicine.

Fenton reaction, a typical inorganic reaction, is broadly utilized in the field of wastewater treatment. Recently In case of its ability to inhibit the growth of cancer cells, it has been frequently reported in cancer treatment. Using the unique tumor microenvironment in cancer cells, many iron-based nanoparticles have been developed to release iron ions in cancer cells to induce Fenton reaction. In this mini review, we outline several different types of iron-based nanoparticles and several main means to enhance Fenton reaction in cancer cells. Finally, we discussed the advantages and disadvantages of iron-based nanoparticles for cancer therapy, prospected the future development of iron-based nanoparticles. It is believed that iron-based nanoparticles can make certain contribution to the cause of human cancer in the future.

Casticin has wide-ranging functional activities, but its water solubility is poor in food products. Here, a nanoemulsion stabilized by Maillard whey protein isolate conjugates (MWPI) was fabricated to encapsulate casticin. The nanoemulsion, with an average diameter of 200 nm, possessed the capability to load 700 μg/g casticin. MWPI-stabilized nanoemulsion showed better stability than that of the WPI nanoemulsion during 4 weeks of storage. Both the inhibition effects of the casticin-loaded nanoemulsion on cancer cells and the process of cellular uptake were studied. Results revealed that the casticin-loaded nanoemulsion had better inhibitory activity in HepG2 and MCF-7 cells than free casticin. Cellular uptake of the nanoemulsion displayed a time-dependent manner. After the nanoemulsion passed into HepG2 and MCF-7 cells, it would locate in the lysosome but not in the nucleus. The main pathway for the nanoemulsion to enter HepG2 cells was pinocytosis, whereas, it entered MCF-7 predominantly through the clathrin-mediated pit. This work implies that MWPI-stabilized nanoemulsions could be utilized as an effective delivery system to load casticin and have the potential to be applied in the food and pharmaceutical industries.

The abundantly released tail-gas from lignocellulose pretreatment with phosphoric acid plus hydrogen peroxide (PHP) was found to accelerate the aging of latex/silicone textural accessories of the pretreatment device. Inspired by this, tail-gas was utilized to control organic pollutants. Methylene blue (MB), as a model pollutant, was rapidly decolorized by the tail-gas, and oxidative degradation was substantially proven by full-wavelength scanning with a UV–visible spectrometer. The tail-gas from six typical lignocellulosic feedstocks produced 68.0–98.3% MB degradation, suggesting its wide feedstock compatibility. Three other dyes, including rhodamine B, methyl orange and malachite green, obtained 97.5–99.5% degradation; moreover, tetracycline, resorcinol and hexachlorobenzene achieved 73.8–93.7% degradation, suggesting a superior pollutant compatibility. In a cytotoxicity assessment, the survival rate of the degraded MB was 103.5% compared with 80.4% for the untreated MB, implying almost no cytotoxicity after MB degradation. Mechanism investigations indicated that the self-exothermic reaction in PHP pretreatment drove the self-generated peroxy acids into tail-gas. Moreover, it heated the pollutant solution and thermally activated peroxy acids as free radicals for efficient pollutant degradation. Here, a brand-new technique for degrading organic pollutants with a “Win–Win–Win” concept was purposed for lignocellulose valorization, pollutant control by waste tail-gas, and biofuel production.

Water availability is a major constraint for wheat production in the southeast of the Loess Plateau, China. Plastic mulch exhibits greater potential in rainwater harvesting while nitrogen (N) fertilizer has a strong effect on soil water utilization. Most of annual precipitation in the Loess Plateau occurs in summer. Rainwater retention in summer fallow becomes very important for winter wheat production in the dryland of the Loess Plateau. Straw mulching in summer fallow are commonly used to prevent water evaporation from soil surface and retain rainwater. Recently plastic mulching has also been used. Nitrogen inputs have also a significant impact on soil water utilization and yield production. However, there is little information available for the effects of full coverage of plots with plastic mulch (PM) in summer fallow on soil water storage at sowing and N rates interact with the soil water utilization in winter wheat yield, water use efficiency (WUE) and grain protein concentration (GPC). Therefore, field experiments were conducted in three consecutive years with variable rainfall. The results showed that PM in summer fallow increased soil water storage at sowing by at least 50 mm, and water storage efficiency was the highest (56.5%) in the dry season. Spatio-temporal dynamics in the soil water storage of 0–300 cm depth exhibited a downward movement with crop development. Approximately half of soil water consumption from flowering to maturity was derived from the 200–300 cm soil layers. The optimal N rate with PM increased grain yield by 27% in the wet season, 36% in the normal season, and 41% in the dry season. PM in combination with optimized N could improve WUE only when annual rainfall is equal to or above the yearly average. Furthermore, evapotranspiration is negatively correlated with GPC although the soil water consumption from 200 to 300 cm depth is positively correlated with post-anthesis N uptake. This suggests that the additional N is needed to further increase GPC. In the season with soil water storage of 550–600 mm at sowing, the N rate of 225 kg ha−1 with PM could achieve the highest yield and 13.2% of GPC. In the season with soil water storage of 450–550 mm at sowing, the N rate of 150 kg ha−1with PM could achieve the highest yield, and 14.3% of GPC. When the season with soil water storage of approximately 400 mm, the N rate of 75 kg ha−1 with PM achieved the highest yield, and 15.0% of GPC. Our results indicate that adjusting N fertilizer inputs based on seasonal variation in summer rainfall could enhance wheat yield and GPC in the southeast region of the Loess Plateau.

Hemp fiber, as a kind of renewable textile fiber, has evoked much interest due to its excellent properties in various fields. It has been investigated in just one step to finish the process of chemo-enzymatic degumming and modification of hemp fiber, which is done in acetic acidsodium acetate buffer solution containing laccase (6.0 g), hemicellulase (0.3 g) and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (0.3 g) under a mild condition (pH 5, 50C). The degumming effects of different batches of raw hemp fibers were also discussed. We found that the residual rate, fineness, length and tensile strength of degummed fiber were 15–27%, 9.00–24.00 dtex, 14.00–19.00 cm and 3.8–5.1 cN/dtex, respectively. Meanwhile, some of the oxidized functional groups were introduced into degummed fiber, which improved the moisture absorption and water retention value of the hemp fiber. The hemp fiber treated by this process could be further improved and then applied in the textile industry.

Sowing date and seeding rate are critical for productivity of winter wheat (Triticum aestivum L.). A three-year field experiment was conducted with three sowing dates (20 September (SD1), 1 October (SD2), and 10 October (SD3)) and three seeding rates (SR67.5, SR90, and SR112.5) to determine suitable sowing date and seeding rate for high wheat yield. A large seasonal variation in accumulated temperature from sowing to winter dormancy was observed among three growing seasons. Suitable sowing dates for strong seedlings before winter varied with the seasons, that was SD2 in 2012–2013, SD3 in 2013–2014, and SD2 as well as SD1 in 2014–2015. Seasonal variation in precipitation during summer fallow also had substantial effects on soil water storage, and consequently influenced grain yield through soil water consumption from winter dormancy to maturity stages. Lower consumption of soil water from winter dormancy to booting stages could make more water available for productive growth from anthesis to maturity stages, leading to higher grain yield. SD2 combined with SR90 had the lowest soil water consumption from winter dormancy to booting stages in 2012–2013 and 2014–2015; while in 2013–2014, it was close to that with SR67.5 or SR112.5. For productive growth from anthesis to maturity stages, SD2 with SR90 had the highest soil water consumption in all three seasons. The highest water consumption in the productive growth period resulted in the best grain yield in both low and high rainfall years. Ear number largely contributed to the seasonal variation in grain yield, while grain number per ear and 1 000-grain weight also contributed to grain yield, especially when soil water storage was high. Our results indicate that sowing date and seeding rate affect grain yield through seedling development before winter and also affect soil water consumption in different growth periods. By selecting the suitable sowing date (1 October) in combination with the proper seeding rate of 90 kg ha–1, the best yield was achieved. Based on these results, we recommend that the current sowing date be delayed from 22 or 23 September to 1 October.

Additional file 1: Supplementary Figure 1. The flow chart of the participants. This figure illustrates the flow of inclusion and exclusion of subjects in the analysis.

Additional file 1.

Numerous researches have proved that deep neural networks (DNNs) can fit everything in the end even given data with noisy labels, and result in poor generalization performance. However, recent studies suggest that DNNs tend to gradually memorize the data, moving from correct data to mislabeled data. Inspired by this finding, we propose a novel method named Dynamic Loss Thresholding (DLT). During the training process, DLT records the loss value of each sample and calculates dynamic loss thresholds. Specifically, DLT compares the loss value of each sample with the current loss threshold. Samples with smaller losses can be considered as clean samples with higher probability and vice versa. Then, DLT discards the potentially corrupted labels and further leverages supervised learning techniques. Experiments on CIFAR-10/100 and Clothing1M demonstrate substantial improvements over recent state-of-the-art methods. In addition, we investigate two real-world problems for the first time. Firstly, we propose a novel approach to estimate the noise rates of datasets based on the loss difference between the early and late training stages of DNNs. Secondly, we explore the effect of hard samples (which are difficult to be distinguished) on the process of learning from noisy labels.

Membrane separation is recognized as one of the most effective strategies to treat the complicated wastewater system for economic development. However, serious membrane fouling has restricted its further application. Inspired by sphagnum, a 0D/2D heterojunction composite membrane is engineered by depositing graphitic carbon nitride nano/microspheres (CNMS) with plentiful wrinkles onto the polyacrylic acid functionalized carbon nanotubes (CNTs-PAA) membrane through hydrogen bond force. Through coupling unique structure and chemistry properties, the CNTs-PAA/CNMS heterojunction membrane presents superhydrophilicity and underwater superoleophobicity. Furthermore, thanks to the J-type aggregates during the solvothermal process, it is provided with a smaller bandgap (1.77 eV) than the traditional graphitic carbon nitride (g-C

The secretions of the venom glands, dry skin and whole body of several Bufo species have been used as traditional medicines in East Asia to treat heart failure and cancer. Due to the highly similar morphological features of Bufo species and their derived commercial crude drugs, along with the high similarity of chemical composition of the secretions of venom glands, it is very challenging to identify the medicinal toads and the related crude drugs. The cyt-b sequences provide useful information to authenticate medicinal Bufo species. Based on the cyt-b sequences, a simple PCR-RFLP method was established for the identification of the medicinally used Bufo species as well as their derived crude drugs. The 23 specimens from three medicinally used Bufo species, B. bufo gargarizans (Bbg), B. melanostictus (Bm) and B. raddei (Br), were clearly divided into 3 groups according to the sequences of amplified cyt-b regions, which could be digested by specific restriction enzymes NcoI, EcoRV and BstXI, respectively. Then the specific PCR-RFLP method was further used to identify 9 samples of commercial crude drugs even with serious degradation of DNA, and all nine samples were identified as B. bufo gargarizans. The method is suitable for identification of medicinally used Bufo species and the related crude drugs.

Two new indole alkaloids, Bufotenidine B (2) and Bufocarboline A (6), along with seven known indole alkaloids (1, 3–5, and 7–9) and three organic acids (10–12), were isolated from the water extract of toad venom. The structures of the new alkaloids were elucidated by extensive spectroscopic methods. The absolute configurations of 4, 6, and 8 were determined for the first time by electronic circular dichroism (ECD) calculations. The cytotoxic activity of all compounds was tested against human malignant melanoma cells A375 by the MTT method, and no antitumor activity was observed.

Poor mechanical performances severely limit the application of hydrogels in vivo; for example, it is difficult to perform a very common suturing operation on hydrogels during surgery. There is a growing demand to improve the mechanical properties of hydrogels for broadening their clinical applications. Natural polyphenols can match the potential toughening sites in our previously reported PEG-lysozyme (LZM) hydrogel because polyphenols have unique structural units including a hydroxyl group and an aromatic ring that can interact with PEG via hydrogen bonding and form hydrophobic interactions with LZM. By utilizing polyphenols as noncovalent crosslinkers, the resultant PEG-LZM-polyphenol hydrogel presents super toughness and high elasticity in comparison to pristine PEG-LZM with no obvious changes in the initial shape, and it can even withstand the high pressure from sutures. At the same time, the mechanical properties could be widely adjusted by varying the polyphenol concentration. Interestingly, the PEG-LZM-polyphenol hydrogel has a higher water content than other polyphenol-toughened hydrogels, which may better meet the clinical needs for hydrogel materials. Besides, the introduction of polyphenols endows the hydrogel with improved antibacterial and anti-inflammatory abilities. Finally, the PEG-LZM-polyphenol (tannic acid) hydrogel was demonstrated to successfully patch a rabbit myocardial defect by suturing for 4 weeks and improve the wound healing and heart function recovery compared to autologous muscle patches.