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The density, temperature, and punch head velocity are dominant factors to the variation of the compacted snow hardness measured by penetrometers. This effect is essential to the construction and operation of compacted snow roads. The Improved Motor-driven Snow Penetrometers (IMSP) are utilized in this research to control the penetration speed and measure the true cone hardness during snow penetration. This study employs a multi-method approach combining orthogonal experiments and the Support Vector Regression (SVR) technique to analyze the effects of these three factors on snow hardness. The results of this investigation indicate that, under identical conditions, density is positively correlated with the hardness of compacted snow, and its sensitivity and significance to the compacted snow hardness are the greatest. Temperature and penetration speed have an effect on hardness, which cannot be completely ignored. The hardness of snow close to its melting point, regardless of its density, decreases significantly at high penetration rates. This study investigates the factors that influence the hardness of compacted snow and provides substantial technical support for the design, construction, and maintenance of snow roads.

Acquisition of continuous drift ice characteristic parameters such as ice size, shape, concentration, and drift velocity are of great importance for understanding river freezing and thawing processes. This study acquired hourly oblique images captured by a shore-based camera in the winter of 2021–2022 on the Yellow River, China. The pixel point scale method for correcting oblique images is provided. The 61 lines were measured at the calibration site and the absolute error between the measured value and the calculated value was in the range of 0.009–0.850 m, with a mean error of 0.236 m. After the correction of oblique images, the true equivalent diameter of drift ice during the freezing period ranged from 0.52–13.10 m with a mean size of 3.36 m, which was larger than that of 2.30 m during the thawing period which ranged from 0.20–12.54 m. It was found that the size of drift ice increased with time during the freezing period and decreased with time during the thawing period. The fractal dimension and roundness were used to represent drift ice shape. The fractal dimension ranged from 1.0–1.3 and the roundness ranged from 0.1–1.0. A Gaussian distribution was used to estimate drift ice size and shape distributions. There is a nonlinear relationship between ice concentration and drift velocity, which can be well expressed by the logistic function. In the future, drift ice parameters for more years and hydrometeorological data for the same time need to be accumulated, which helps to analyze the freezing and thawing patterns of river ice.

Due to the increasing depletion of petroleum resources, the production route of non-oil-based aviation kerosene has been paid more and more attention. In this regard, the process of preparing aviation kerosene from syngas (CO and H2) is one of the most promising industrial alternative fuel production routes. The traditional syngas-to-aviation kerosene catalyst uses iron-based and cobalt-based catalysts, which is a complex process with a high cost. In this work, a hierarchical Co/Beta metal-zeolite bifunctional catalyst prepared via the melting method is reported, which can directly and highly selectively produce an aviation kerosene component from syngas (CO and H2). Compared with the catalyst prepared via the impregnation method, the Co/Beta catalyst prepared via the melting method has smaller, more highly dispersed Co metal active species and more suitable acid properties, the conversion of CO can reach 34.6%, and the selectivity of the C8-C16 aviation kerosene component can reach 40.2%, which provides a new idea for the industrial production of aviation kerosene.

Abstract Background Subacute combined degeneration (SCD) is a neurological complication commonly associated with vitamin B12 deficiency. It can result from nitrous oxide (N2O) abuse and cause neuropsychiatric symptoms. However, there has been no literature regarding alterations of serum copper and cerebellum in SCD patients. Case presentation We reported two cases of young SCD patients with histories of N2O abuse. In these cases, elevated homocysteine, macrocytic anemia, spinal cord abnormalities, and peripheral nerve injuries were detected. In addition, decreased serum copper level and cerebellar atrophy were reported for the first time. The patients’ symptoms improved after withdrawal of N2O exposure and vitamin B12 supplements. Conclusion We reported two SCD cases with serum copper alteration and cerebellar atrophy after N2O abuse for the first time. These might be crucial complements to the diagnosis of SCD.

The operation condition of wind turbine is complex with frequent load disturbances. However, the traditional rigid connection wind turbine has shortcomings in rejecting impact load disturbance. In this paper, a novel double rotor wind turbine generation system is proposed. Firstly, the concept design of the new system is carried out by adopting the technical route of ”double rotor machine + electrically excited synchronous generator”, and the main components and structural forms of the system are given. Then, the balance equations of speed, torque and power are derived based on the principles of kinematics and electrotechnics. Finally, the characteristics of the double rotor wind turbine generation system under different wind conditions are analyzed through simulation, where the anti-impact load capacity is evaluated. The simulation results show the superiority of the proposed novel double rotor wind turbine generation system.

Abstracts Background In recent years, HIV testing has become one of the effective strategies to reduce the risk of the infection. Frequent quarterly HIV testing can be cost effective. Therefore, an in-depth study of factors related to the testing behavior of men who have sex with men (MSM) were analyzed to optimize intervention strategies. Methods From March 2011 to October 2018, the project was implemented in a Tianjin (China) bathhouse, and 5165 MSM were surveyed using snowball sampling. Factors related to HIV testing behavior were analyzed by ordinal logistic regression analysis after grouping according to testing frequency, and comprehensive analysis was performed. Results The multivariate logistic analysis showed that 6 variables including young MSM (OR = 0.67, 95% CI: 0.49–0.92, p = 0.01), low-educated MSM (OR = 0.60, 95% CI: 0.48–0.77, p

BackgroundOsteoarthritis has the characteristics of degenerative changes in articular cartilage and secondary osteoporosis, and it is a common chronic irreversible joint disease. In addition to affecting articular cartilage, subchondral bone, joint capsule and synovial membrane also undergo pathological changes during the development of the disease. Multiple studies have revealed that patients with osteoarthritis were found to have a significantly increased risk of osteoporosis, which also contributes to the progression of osteoarthritis. However, in the current existing studies, we found that no scholars have used bibliometric analysis in the study of the relationship between osteoarthritis and osteoporosis. From the perspective of bibliometrics, this study summarizes in detail the degree of cooperation between countries, research institutions, authors, and related journals in the field of osteoarthritis and osteoporosis research and their respective influence. In this way, the evolution of knowledge structure, the change of research focus and the hot topics with research potential in the future can be further visualized and analyzed.MethodsSearch the Web of Science core collection in Science Citation Index Expanded for articles and reviews of research on osteoarthritis and osteoporosis from 1998 to 2021. Bibliometric tools such as VOSviewer, CiteSpace, were be frequently used in our study. They are mainly used to analyze collaborations between countries, research institutions, and publication authors. Meantime, co-citation analysis of journals, co-occurrence analysis of keywords and subject categories will also be reflected in the study.ResultsAccording to the search strategy, 1,078 publications were included during the period 1998–2021. And the number of annual publications on the relationship between osteoarthritis and osteoporosis is on the rise. The United States has achieved the most and contributed the most in this field and the Boston University was the most prolific institution. For the statistical analysis of published publications, Reginster JY had the highest number of publications, while Felson DT had the highest co-citation frequency. Respectively, Osteoarthritis And Cartilage was the most productive journal in this area of research. The keywords “inflammation,” “expression,” and “mesenchymal stem cells” may also be the development trend and research hotspot of the future research direction in this field.ConclusionsIn our study, the relationship between osteoarthritis and osteoporosis was analyzed by using literature measurement. These analysis results can lead researchers to learn more directly about the trend in this area and provide guidance for determining popular research directions.

Aquatic ecosystems are globally significant sources of greenhouse gases (GHG) to the atmosphere, offsetting the terrestrial sinks. A one-year field study was carried out in a shallow eutrophic Lake Wuliangsuhai, Inner Mongolia (draining waters from one of the largest irrigation areas in China), to estimate diffusive GHG fluxes and their relative importance in global warming potential (GWP). Our results showed high spatiotemporal variation in dissolved CO2, CH4 and N2O concentrations, while they did not differ significantly between the bottom and surface layers of the shallow waterbody. In general, GHG concentrations and diffusive fluxes were higher in the north part of the lake than in the south. GHG concentrations in the water under the ice were significantly higher than those during the open-water period. Spatial variability of GHG concentrations varied with the bathymetry of the lake. The location of study sites relative to the main inflow and abundance of submerged macrophytes were the main controlling factors of GHG concentrations, as indicated by the consistency of GHG concentrations at the sampling sites, particularly for N2O. The total diffusive GHG emission from Lake Wuliangsuhai was 76.9 ± 5.4 Gg CO2 equivalents yr−1, with CO2, CH4 and N2O contributing 16 %, 83 %, and 1 %, respectively. Overall, the results suggest that shallow lakes in mid-latitude arid areas with cold winters can be potentially important GHG sources. However, those lakes are insufficiently represented in the scientific literature, and therefore they deserve more research attention.

Study region: This study focuses on three data-limited inland river basins in the arid Hexi Corridor, Northwest China. Study focus: The lack of ground-based observation data for estimating potential evapotranspiration (PET) usually limits the streamflow simulation. This study explored the feasibility of using three gridded PET datasets (GLDAS, GLEAM, and ERA5) to force the hydrologic model. The hydrologic performance of these PET datasets was investigated using the HBV-light model. New hydrological insights for the region: The results show that GLEAM performs best in estimating PET on both a daily and monthly scale. GLDAS generally captures the seasonal variations and patterns well but shows a higher estimation in magnitude. For the hydrological simulation, all three PET datasets can be used as forcing data to drive the HBV-light model, as the Nash-Sutcliffe efficiency (NSE) values are greater than 0.64 during the validation period for the three PET inputs in the three basins. The magnitude and temporal signal of PET forcing data do not significantly affect streamflow simulations of the HBV-light. The model mainly adjusts the water content of the soil box (WCS) to eliminate the efficiency loss caused by the PET magnitude difference to achieve the best simulation results.

In order to investigate the causes of the differences in heat tolerance (‘Lu He Hong’ and ‘Zhi Hong’), we studied the physiological changes, photosynthetic properties and regulatory mechanism of the two peony cultivars at high temperature. The results showed that the physiological changed of different peony cultivars varied significantly under high temperature stress. With the extension of high temperature stress time, MDA content of 'Lu He Hong' increased,while 'Zhi Hong' rised first and then decreased, SOD activity of 'Lu He Hong' rised first and then decreased, that of 'Zhi Hong' kept rising, POD activity of 'Lu He Hong' kept decreasing, while 'Zhi Hong' rised. The photosynthetic instrument records the change of peony photosynthesis parameters at high temperature; the chlorophyll A (Chla) fluorescence transient is recorded using the plant efficiency analyzer (PEA), analyzed according to the JIP test (O-J-I-P fluorescence transient analysis), and several parameters were derived to explain the photosynthetic efficiency difference between different peony cultivars. The tested cultivars responded differently to the survey conditions, and the PCA analysis showed that the ‘Zhi Hong’ was more well tolerated and showed better thermal stability of the PSII. The reduced efficiency of the ‘Lu He Hong’ PSII antenna leads to higher heat dissipation values to increase the light energy absorbed by unit reaction center (ABS/RC), the energy captured by unit reaction center (TR0/RC), and the energy dissipated by unit reaction center (DI0/RC), which significantly leads to its lower total photosynthetic performance (PItotal). The light capture complex of the variety ‘Zhi Hong’ has high connectivity with its reaction center, less damage to OEC activity, and better stability of the PSII system. The results show that ‘Zhi Hong’ improves heat resistance by stabilizing the cell membrane, a strong antioxidant system, as well as a more stable photosynthetic system. The results of this study provide a theoretical basis for the screening of heat-resistant peonies suitable for cultivation in Jiangnan area and for the selection and breeding of heat-resistant cultivars.

BackgroundCurrently, many targeted drugs are approved for treatment of ALK fusion non-small cell lung cancer. However, it has been previously assumed that patients with 5′ non-oncogenic kinase (5′ NOK) fusion detected by DNA next-generation sequencing (NGS) would not benefit from ALK inhibitors because of lack of an intact kinase domain.Case descriptionA novel 5′ NOK fusion form, ALK-CYP27C1 (A19:C5), was detected by DNA NGS in surgical tissue specimens of a patient with recurrent lung adenosquamous carcinoma. The patient achieved 29 months of progression-free survival with ensartinib treatment. The results of RNA NGS from the same operative tissue identified EML4-ALK (E13:A20) fusion variant type I.ConclusionThis is the first case to provide real-world evidence of effective treatment of a patient with the 5′ NOK fusion form at the DNA level but functional EML4-ALK at the RNA level, illustrating the need for RNA testing in 5′ NOK patients.

Abstract Background Systemic lupus erythematosus (SLE) is an autoimmune disease that can involve multiple organs or systems. Lupus nephritis (LN) is associated with high mortality and morbidity. However, plenty of patients do not respond to present treatment or relapse. Iguratimod (IGU) is a new small molecular, anti-rheumatic drug and has shown the potential for drug repurposing from rheumatoid arthritis (RA) to LN treatment. It has been approved for treating RA in northeast Asia. Beyond expectation in a recent observational study, over 90% of thirteen refractory LN patients responded to iguratimod monotherapy in 24 weeks, with no steroids dose increasing or any other medication add-on during the entire follow-up. Methods/design This study is a multi-center, randomized, 52-week parallel positive drug-controlled study. The study was designed as a head-to-head comparison between the iguratimod and present first-line therapy on LN patients. A total of 120 patients (60 patients each group) is in the enrolling plan. All enrolled patients are assigned randomly into trial and control groups. The patients will be selected from six study sites in China and will all have biopsy-proven active lupus nephritis. In the first 24 weeks of the trial, IGU is compared with cyclophosphamide as an induction therapy, and in the second 24 weeks, IGU is compared with azathioprine as a maintenance therapy. The primary outcome is renal remission rate including both complete remission and partial remission at week 52, which will be analyzed using a non-inferiority hypothesis test. Discussion Most patients diagnosed with SLE will develop LN within 5 years and LN remains a major cause of morbidity and death for SLE patients. Although some medications are proven effective for the treatment of this condition, at least 20–35% LN patients have to suffer from relapse or ineffective treatment and medication intolerance is also frequent. This trial is designed to demonstrate whether iguratimod can be used as an alternative induction or maintenance therapy in subjects who have lupus nephritis. Data from this study will provide an evidence on whether or not iguratimod should be recommended to active LN patients. Trial registration ClinicalTrials.gov NCT 02936375 . Registered on October 18, 2016.

Multiple types of brain-control systems have been applied in the field of rehabilitation. As an alternative scheme for balancing user fatigue and the classification accuracy of brain–computer interface (BCI) systems, facial-expression-based brain control technologies have been proposed in the form of novel BCI systems. Unfortunately, existing machine learning algorithms fail to identify the most relevant features of electroencephalogram signals, which further limits the performance of the classifiers. To address this problem, an improved classification method is proposed for facial-expression-based BCI (FE-BCI) systems, using a convolutional neural network (CNN) combined with a genetic algorithm (GA). The CNN was applied to extract features and classify them. The GA was used for hyperparameter selection to extract the most relevant parameters for classification. To validate the superiority of the proposed algorithm used in this study, various experimental performance results were systematically evaluated, and a trained CNN-GA model was constructed to control an intelligent car in real time. The average accuracy across all subjects was 89.21 ± 3.79%, and the highest accuracy was 97.71 ± 2.07%. The superior performance of the proposed algorithm was demonstrated through offline and online experiments. The experimental results demonstrate that our improved FE-BCI system outperforms the traditional methods.

In the ice-infested Bohai Sea, ice-breaking cones are generally installed on offshore wind turbine towers for ice resistance. Bending failure is a frequent ice failure mode occurring when ice interacts with ice-breaking cones. Global warming prolongs the ice formation period in the Bohai Sea, inducing an increasing trend of granular ice fraction in ice sheets. To better understand the bending mechanical behaviors of granular sea ice in the Bohai Sea, laboratory three-point bending tests were conducted using granular sea ice collected in the Bohai Sea during the winter of 2010–2011. A total of 42 ice samples were tested at −5, −10, and −15°C with strain rates of 1 × 10−6–6×10−4 s−1 in the downward direction vertical to the original ice surface. During tests, the salinity and density of each ice specimen were measured to calculate the porosity. Based on the results, negative exponential relationships were proposed between flexural strength and the square root of porosity and between effective elastic modulus and porosity. After normalization, the flexural strength showed no rate dependence at the whole strain rate range. In contrast, the effective elastic modulus increased with the strain rate. The effective elastic modulus of the ice samples was further parameterized based on the porosity and strain rate.

ObjectiveTo investigate the association between the structural deformity and foot pain in hallux valgus (HV) patients using a multi-variate pattern analysis (MVPA) approach.MethodsPlain radiographic metrics were calculated from 36 painful and 36 pain-free HV feet. In analysis 1, univariate analyses were performed to investigate the clinical and radiographic differences between painful and pain-free HV. In analysis 2, we investigated the pattern differences for radiographic metrics between these two groups using a MVPA approach utilizing a support vector machine. In analysis 3, sequential backward selection and exhaustive search were performed as a feature-selection procedure to identify an optimal feature subtype. In analysis 4, hierarchical clustering analysis was used to identify the optimal radiographic HV subtype associated with pain in HV.ResultsWe found that: (1) relative to feet with pain-free HV, the painful ones exhibited a higher hallux valgus angle, i.e., the magnitude of distal metatarsal and phalangeal deviation; (2) painful HV could be accurately differentiated from pain-free HV via MVPA. Using sequential backward selection and exhaustive search, a 5-feature subset was identified with optimal performance for classifying HV as either painful or pain-free; and (3) by applying hierarchical clustering analysis, a radiographic subtype with an 80% pain incidence was identified.ConclusionThe pain in HV is multifactorial and associated with a radiographic pattern measured by various angles on plain radiographs. The combination of hallux valgus angle, inter-phalangeal angle, distal metatarsal articular angle, metatarsal cuneiform angle and metatarsal protrusion distance showed the optimal classification performance between painful and pain-free HV.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with highly heterogeneous clinical symptoms and severity. There is complex pathogenesis of SLE, one of which is IFNs overproduction and downstream IFN-stimulated genes (ISGs) upregulation. Identifying the key ISGs differentially expressed in peripheral blood mononuclear cells (PBMCs) of patients with SLE and healthy people could help to further understand the role of the IFN pathway in SLE and discover potential diagnostic biomarkers.The differentially expressed ISGs (DEISG) in PBMCs of SLE patients and healthy persons were screened from two datasets of the Gene Expression Omnibus (GEO) database. A total of 67 DEISGs, including 6 long noncoding RNAs (lncRNAs) and 61 messenger RNAs (mRNAs) were identified by the “DESeq2” R package. According to Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, those DEISGs were mainly concentrated in the response to virus and immune system processes. Protein-protein interaction (PPI) network showed that most of these DEISGs could interact strongly with each other. Then, IFIT1, RSAD2, IFIT3, USP18, ISG15, OASL, MX1, OAS2, OAS3, and IFI44 were considered to be hub ISGs in SLE by “MCODE” and “Cytohubba” plugins of Cytoscape, Moreover, the results of expression correlation suggested that 3 lncRNAs (NRIR, FAM225A, and LY6E-DT) were closely related to the IFN pathway.The lncRNA NRIR and mRNAs (RSAD2, USP18, IFI44, and ISG15) were selected as candidate ISGs for verification. RT-qPCR results showed that PBMCs from SLE patients had substantially higher expression levels of 5 ISGs compared to healthy controls (HCs). Additionally, statistical analyses revealed that the expression levels of these ISGs were strongly associated to various clinical symptoms, including thrombocytopenia and facial erythema, as well as laboratory indications, including the white blood cell (WBC) count and levels of autoantibodies. The Receiver Operating Characteristic (ROC) curve demonstrated that the IFI44, USP18, RSAD2, and IFN score had good diagnostic capabilities of SLE.According to our study, SLE was associated with ISGs including NRIR, RSAD2, USP18, IFI44, and ISG15, which may contribute to the future diagnosis and new personalized targeted therapies.

To provide basic drift-ice parameters for new-energy structures in ice-infested nearshore waters, an estimation method of the design drift-ice concentration and floe area was established. A total of 700 satellite images in winters from 2010 to 2021 were used to obtain the drift-ice concentration and floe area from 26 sites in the Bohai Sea. The floe area with 90% cumulative probability was selected as the characteristic floe area in each satellite image. Furthermore, the water temperature threshold ranging from −1.6 °C to −0.5 °C was adopted by considering the drift-ice freezing/melting states because of different salinity values in nearshore waters. The upper limit values of the ice concentration and characteristic floe area at the lowest water temperature of −1.6 °C were finally used as the design drift-ice indexes. The maximum design ice concentrations (floe area) in the Liaodong Bay, Bohai Bay, and Laizhou Bay were 96% (0.43 km2), 91% (0.39 km2), and 87% (0.29 km2), respectively. The design ice concentration at the bay bottom was higher than that near the mouth. The design floe area in the Liaodong Bay and Bohai Bay increased with latitudes, but the trend was opposite in the Laizhou Bay. The method developed in the current study has universal applicability, which can be extended to other ice-cover waters and specific structure designs by adjusting the cumulative probability threshold and the water temperature threshold.

The 8# coal seam in the Benxi Formation of the southeastern margin of the Ordos Basin is a deep coal seam with abundant coalbed methane resources. Calcite veins are commonly developed within the 8# coal seam, and their formation processes and mechanisms have significant implications for the enrichment of deep coalbed methane. Genesis of the calcite veins was analyzed to reveal the impact of the calcite veins formation on coalbed methane accumulation, with an integrated application of petrographic study by thin section, cathodoluminescence analysis, carbon-oxygen isotope analysis, and homogeneous temperature measurements of fluid inclusions. The research findings indicate that the calcite veins in the 8# coal seam can be classified into three stages: C1, C2, and C3. The diagenetic fluids of C1 primarily originated from contemporaneous seawater. The fluids responsible for the formation of C2 primarily consist of organic fluids enriched in biogenic gas, whereas the fluids contributing to the formation of C3 are primarily associated with liquid hydrocarbons originated form decarboxylation of organic matter. Furthermore, the development of both C2 and C3 is influenced by deep hydrothermal fluids resulting from tectonic heating events during the Early Cretaceous. By combining analysis of the hydrocarbon accumulation history and burial history in the study area, it has been established that C2 formation occurred during the Late Triassic to Early Jurassic, while C3 formation took place during the Late Jurassic to Early Cretaceous. The exploration and production practices in the study area have firmly established the crucial significance of the formation and evolution of calcite veins within the 8# coal seam for the migration and accumulation of coalbed methane. The research outcomes provide valuable insights for the exploration of deep coalbed methane enrichment areas.

Populus pruinosa Schrenk has the biological characteristics of heteromorphic leaves and is a pioneer species for wind prevention and sand fixation. The functions of heteromorphic leaves at different developmental stages and canopy heights of P. pruinosa are unclear. To clarify how developmental stages and canopy height affect the functional characteristics of leaves, this study evaluated the morphological anatomical structures and the physiological indicators of leaves at 2, 4, 6, 8, 10, and 12 m. The relationships of functional traits to the developmental stages and canopy heights of leaves were also analyzed. The results showed that blade length (BL), blade width (BW), leaf area (LA), leaf dry weight (LDW), leaf thickness (LT), palisade tissue thickness (PT), net photosynthetic rate (Pn), stomatal conductance (Gs), proline (Pro), and malondialdehyde (MDA) content increased with progressing developmental stages. BL, BW, LA, leaf dry weight, LT, PT, Pn, Gs, Pro, and the contents of MDA, indoleacetic acid, and zeatin riboside had significant positive correlations with canopy heights of leaves and their developmental stages. The morphological structures and physiological characteristics of P. pruinosa leaves showed more evident xeric structural characteristics and higher photosynthetic capacity with increasing canopy height and progressive developmental stages. Resource utilization efficiency and the defense ability against environmental stresses were improved through mutual regulation of each functional trait.

After the formation of the bend ice cover, the ice thickness of the bend is not uniformly distributed, and an open-water area is usually formed downstream of the bend. The spatial and temporal variation of the ice thickness in seven cross sections was determined via Unmanned Aerial Vehicle Ground Penetrating Radar (UAV-GPR) technology and traditional borehole measurements. The plane morphology change of the open water was observed by Sentinel-2. The results show that the average dielectric permittivity of GPR was 3.231, 3.249, and 3.317 on three surveys (5 January 2022, 16 February 2022, and 25 February 2022) of the Yellow River ice growing period, respectively. The average ice thickness of the three surveys was 0.402 m, 0.509 m, and 0.633 m, respectively. The ice thickness of the concave bank was larger than that of the convex bank. The plane morphology of the open water first shrinks rapidly longitudinally and then shrinks slowly transversely. The vertical boundary of the open water was composed of two arcs, in which the slope of Arc I (close to the water surface) was steeper than that of Arc II, and the hazardous distance of the open-water boundary was 10.3 m. The increased flow mostly affected the slope change of Arc I. Finally, we discuss the variation of hummocky ice and flat ice in GPR images and the physical factors affecting GPR detection accuracy, as well as the ice-thickness variation of concave and convex banks in relation to channel curvature.

The topology structure of multi-layer networks is highly correlated with the robustness of consensus. This paper investigates the influence of different interlayer edge connection patterns on the consensus of the two-layer ring networks. Two types of two-layer ring network models are first considered: one is a kind of two-layer ring network with two linked edges between layers (Networks-a), and the other is a kind of two-layer ring network with three linked edges between layers (Networks-b). Using the Laplacian spectrum, the consensus of the network model is derived. The simulation experiments are used to demonstrate the influence of different interlayer edge connection patterns on the consensus of networks. To determine the best edge connection pattern for Networks-a and Networks-b, the number of nodes in a single-layer ring network is denoted by n. The best edge connection pattern for Networks-a is 1 & [(n+2)/2]. Furthermore, n is subdivided into 3k,3k+1,3k+2, and the best edge connection patterns of Networks-b are near 1 & k+1 & 2k+1.

The key to developing highly active α-Fe2O3-based photocatalysts is to improve the charge separation and efficiently utilize the electrons with sufficient thermodynamic energy. Herein, α-Fe2O3 nanosheets (FO) were synthesized using a metal-ion-intervened hydrothermal method and then coupled with SnO2 nanosheets (SO) to obtain SO/FO nanocomposites. Subsequently, nanosized Ag was selectively loaded on SO using the photo-deposition method to result in the ternary Ag-SO/FO nanocomposites. The optimal nanocomposite could realize the efficient aerobic degradation of 2,4-dichlorophenol as a representative organic pollutant under visible-light irradiation (>420 nm), exhibiting nearly six-fold degradation rates of that for FO. Additionally, the Ag-SO/FO photocatalyst is also applicable to the visible-light degradation of other organic pollutants and even CO2 reduction. By using steady-state surface photovoltage spectroscopy, fluorescence spectroscopy, and electrochemical methods, the photoactivity enhancement of Ag-SO/FO is principally attributed to the improved charge separation by introducing SO as an electron platform for the high-energy-level electrons of FO. Moreover, nanosized Ag on SO functions as a cocatalyst to further improve the charge separation and facilitate the catalytic reduction. This work provides a feasible design strategy for narrow-bandgap semiconductor-based photocatalysts by combining an electron platform and a cocatalyst.

It is highly desirable to enhance the photogenerated charge separation of g-C3N4 by constructing efficient heterojunctions, especially with an additional organic constitution for solar–hydrogen conversion. Herein, g-C3N4 nanosheets have been modified controllably with nano-sized poly(3-thiophenecarboxylic acid) (PTA) through in situ photopolymerization and then coordinated with Fe(III) via the -COOH groups of modified PTA, forming an interface of tightly contacted nanoheterojunctions between the Fe(III)-coordinated PTA and g-C3N4. The resulting ratio-optimized nanoheterojunction displays a ~4.6-fold enhancement of the visible-light photocatalytic H2 evolution activity compared to bare g-C3N4. Based on the surface photovoltage spectra, measurements of the amount of •OH produced, photoluminescence (PL) spectra, photoelectrochemical curves, and single-wavelength photocurrent action spectra, it was confirmed that the improved photoactivity of g-C3N4 is attributed to the significantly promoted charge separation by the transfer of high-energy electrons from the lowest unoccupied molecular orbital (LUMO) of g-C3N4 to the modified PTA via the formed tight interface, dependent on the hydrogen bond interaction between the -COOH of PTA and the -NH2 of g-C3N4, and the continuous transfer to the coordinated Fe(III) with -OH favorable for connection with Pt as the cocatalyst. This study demonstrates a feasible strategy for solar-light-driven energy production over the large family of g-C3N4 heterojunction photocatalysts with exceptional visible-light activities.

Sea ice conditions and navigability along four typical routes of the Northeast Passage (NEP) are analysed using remote-sensing data from 1979 to 2019. The influence of air temperature (Tair) and surface wind on the sea ice concentration (SIC) and the navigability of routes is determined. It is found that the annually averaged SICs of the different routes have decreased over the past 41 years. The fastest rate of decrease occurred in the Kara Sea (∼−1% per year), while the slowest rates of decrease occurred in the Laptev/East Siberian Sea (∼−0.42% per year). The number of navigable days for the Kara Sea has become ∼1–2 months longer than the Laptev/East Siberian Sea route as a result. The effect of Tair on SIC, quantified by ΔSIC/ΔTair in the routes through the eastern Kara Sea and Laptev/East Siberian Sea in 2010s was ∼−0.04/°C, two to three times that seen during the 1980s. Air temperature is becoming a significant driving force of melting ice in these routes. Surface winds are also a crucial factor for the navigability of the Vilkitsky Strait and Long Strait, as they drive ice drift, and affect the navigability of the Kara Strait by introducing warm air.

Background and objective There is a certain correlation between vitamin nutritional status and cancer patients. Studies have shown that vitamin deficiency increases the risk of cancer. The purpose of this study is to understand the vitamin D nutritional status of cancer patients and to provide scientific basis for further nutritional intervention. Methods Cancer patients who visited Shandong Cancer Hospital from July 2017 to June 2019 were included in this retrospective study. Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured. Univariate analysis and multiple linear regression analysis were carried out using SPSS 20.0. Results A total of 2,487 cancer patients were evaluable for this analysis. Mean 25(OH)D concentration was (12.70±6.82) ng/mL; the prevalence of vitamin D deficiency [25(OH)D concentration less than 20.00 ng/mL] was of 92.20%. In univariate analysis, age, body mass index (BMI), season and types of cancer were associated with 25(OH)D concentrations. In the multivariate analysis, BMI (β=0.71), age (β=-0.56), season (β=-0.99 for winter; β=-0.76 for autumn vs summer) and types of cancer (β=-1.17 for lung cancer; β=-1.45 for esophageal-gastric cancer; β=-1.05 for colorectal cancer vs other types of cancer) were independently and significantly associated with 25(OH)D levels (P

Abstract Intestinal barrier function defects and dysregulation of intestinal immune responses are two key contributory factors in the pathogenesis of ulcerative colitis (UC). Phenazine biosynthesis-like domain-containing protein (PBLD) was recently identified as a tumor suppressor in gastric cancer, hepatocellular carcinoma, and breast cancer; however, its role in UC remains unclear. Therefore, we analyzed colonic tissue samples from patients with UC and constructed specific intestinal epithelial PBLD-deficient (PBLDIEC−/−) mice to investigate the role of this protein in UC pathogenesis. We found that epithelial PBLD was decreased in patients with UC and was correlated with levels of tight junction (TJ) and inflammatory proteins. PBLDIEC−/− mice were more susceptible to dextran sulfate sodium (DSS)- and 2,4,6-trinitrobenzene sulfonic acid-induced colitis compared with wild-type (WT) mice. In DSS-induced colitis, PBLDIEC−/− mice had impaired intestinal barrier function and greater immune cell infiltration in colonic tissue than WT mice. Furthermore, TJ proteins were markedly reduced in PBLDIEC−/− mice compared with WT mice with colitis. Nuclear factor (NF)-κB activation was markedly elevated and resulted in higher expression levels of downstream effectors (C–C motif chemokine ligand 20, interleukin [IL]-1β, IL-6, and tumor necrosis factor [TNF]-α) in colonic epithelial cells isolated from PBLDIEC−/− mice than WT mice with colitis. PBLD overexpression in intestinal epithelial cells (IECs) consistently inhibited TNF-α/interferon-γ-induced intestinal barrier disruption and TNF-α-induced inflammatory responses via the suppression of NF-κB. In addition, IKK inhibition (IKK-16) rescued excessive inflammatory responses induced by TNF-α in PBLD knockdown FHC cells. Co-immunoprecipitation assays showed that PBLD may interact with IKKα and IKKβ, thus inhibiting NF-κB signaling, decreasing inflammatory mediator production, attenuating colonic inflammation, and improving intestinal barrier function. Modulating PBLD expression may provide a novel approach for treatment in patients with UC.

The recent rapid changes in Arctic sea ice have occurred not only in ice thickness and extent, but also in the microstructure of ice. To understand the role of microstructure on partitioning of incident solar shortwave radiation within the ice and upper ocean, this study investigated the sensitivity of the optical properties of summer sea ice on ice microstructures such as the volume fraction, size, and vertical distribution of gas bubbles, brine pockets, and particulate matter (PM). The results show that gas bubbles are the predominant scatterers within sea ice. Their effects on the scattering coefficient and ice albedo are 5 and 20 times stronger respectively than the effect of brine pockets. Albedo and transmittance of ice decrease with higher concentration and larger size of PM particles. A 4-cm top layer of ice with high PM concentration (50 g/m3) results in a 10% increase in radiation absorption. The role of ice microstructure in the partitioning of radiation transfer is more important for seasonal than for multiyear ice, and more important for ponded than for snow-covered ice. Varying ice microstructure can obviously alter solar radiation transfer in the ice-ocean system, even with a constant ice thickness. Our results suggest that numerical models should take the variable microstructure of sea ice into account to improve model accuracy and to understand the interaction between internal variations in Arctic sea ice and the ocean, especially in summer.

It has been claimed that individuals with schizophrenia have difficulty in self-recognition and, consequently, are unable to identify the sources of their sensory perceptions or thoughts, resulting in delusions, hallucinations, and unusual experiences of body ownership. The deficits also contribute to the enhanced rubber hand illusion (RHI; a body perception illusion, induced by synchronous visual and tactile stimulation). Evidence based on RHI paradigms is emerging that auditory information can make an impact on the sense of body ownership, which relies on the process of multisensory inputs and integration. Hence, we assumed that auditory verbal hallucinations (AVHs), as an abnormal auditory perception, could be linked with body ownership, and the RHI paradigm could be conducted in patients with AVHs to explore the underlying mechanisms. In this study, we investigated the performance of patients with/without AVHs in the RHI. We administered the RHI paradigm to 80 patients with schizophrenia (47 with AVHs and 33 without AVHs) and 36 healthy controls. We conducted the experiment under two conditions (synchronous and asynchronous) and evaluated the RHI effects by both objective and subjective measures. Both patient groups experienced the RHI more quickly and strongly than HCs. The RHI effects of patients with AVHs were significantly smaller than those of patients without AVHs. Another important finding was that patients with AVHs did not show a reduction in RHI under asynchronous conditions. These results emphasize the disturbances of the sense of body ownership in schizophrenia patients with/without AVHs and the associations with AVHs. Furthermore, it is suggested that patients with AVHs may have multisensory processing dysfunctions and internal timing deficits.

Graphical Abstract

Abstract The development of yeast that converts raw corn or cassava starch to ethanol without adding the exogenous α-amylase and/or glucoamylase would reduce the overall ethanol production cost. In this study, two copies of codon-optimized Saccharomycopsis fibuligera glucoamylase genes were integrated into the genome of the industrial Saccharomyces cerevisiae strain CCTCC M94055, and the resulting strain CIBTS1522 showed comparable basic growth characters with the parental strain. We systemically evaluated the fermentation performance of the CIBTS1522 strain using the raw corn or cassava starch at small and commercial-scale, and observed that a reduction of at least 40% of the dose of glucoamylase was possible when using the CIBTS1522 yeast under real ethanol production condition. Next, we measured the effect of the nitrogen source, the phosphorous source, metal ions, and industrial microbial enzymes on the strain’s cell wet weight and ethanol content, the nitrogen source and acid protease showed a positive effect on these parameters. Finally, orthogonal tests for some other factors including urea, acid protease, inoculum size, and glucoamylase addition were conducted to further optimize the ethanol production. Taken together, the CIBTS1522 strain was identified as an ideal candidate for the bioethanol industry and a better fermentation performance could be achieved by modifying the industrial culture media and condition.

Diffuse solar radiation (Rd) provides basic data for designing and optimizing solar energy systems. Owing to the notable unavailability in many regions of the world, Rd is traditionally estimated by models through other easily available meteorological factors. However, in the absence of ground weather station data, such models often need to be supplemented according to satellite remote sensing data. The performance of Himawari-7 satellite inversion of Rd was evaluated in the study, and hybrid models were established (XGBoost_DE, XGBoost_FPA, XGBoost_GOA, and XGBoost_GWO), so as to improve the satellite data and achieve a better utilization effect. The meteorological data of 14 Rd stations in mainland China from 2011 to 2015 were used. Four input combinations (L1–L4) and eight input combinations (S1–S8) of meteorological factors corresponding to satellite remote sensing data were used for model simulation, while two optimal combinations (S7 and S8) were selected for cross-station application. The results revealed that the accuracy of Himawari-7 satellite Rd data was low, with RMSE, R2, MAE, and MBE values of 2.498 MJ·m−2·d−1, 0.617, 1.799 MJ·m−2·d−1, and 0.323 MJ·m−2·d−1, respectively. The performance of these coupled models based on satellite data was significantly improved. The RMSE and MAE values increased by 15.5% and 9.4%, respectively, while the R2 value decreased by 10.9 %. Compared with others based on satellite data, the XGBoost_GOA model exhibited optimal performance. The mean values of RMSE, R2, and MAE were 1.63 MJ·m−2·d−1, 0.76 and 1.21 MJ·m−2·d−1, respectively. The XGBoost_GWO model exhibited optimal performance in the cross-station application, and the average RMSE value was reduced by 2.3–10.5% compared with the other models. The meteorological factors input by the models exhibited different levels of significance in different scenarios. Rd_s was the main meteorological parameter that affected the model based on satellite data, while RH exhibited a significant improvement in the XGBoost_FPA and XGBoost_GWO models based on ground weather stations data. Accordingly, the present authors believe that the XGBoost_GOA model has excellent ability for simulating Rd, while the XGBoost_GWO model allows for cross-station simulation of Rd from satellite data.

The ice thermal parameters are the key to reasonably simulating ice phenology, distribution, and thickness, but they have always been a “vulnerable group” in ice research. Technically, it may seem simple to obtain accurate ice thermal property parameters, but in reality, there are numerous impact factors, requiring a rigorous research process. In the 1980s, the thermal conductivity of ice was explored in the field and laboratory, after which there has been no significant progress in China. In this century, mathematics is introduced, after which the inversion identification and analysis with the time-series data of the vertical temperature profiles of ice layers by in situ testing are carried out. The in situ thermal diffusivities of different natural ices were obtained and cross-validated with the inversion identification results. Both natural freshwater ice and sea ice exhibited differences in the thermal diffusivity of the pure ice chosen for the current simulations due to impurities within the unfrozen water among the ice crystals, but the trends are consistent with the results of a small number of laboratory tests on different types of saltwater frozen ice. In this paper, the inversion identification results of the thermal diffusivity of typical ice were selected, and the factors constraining the thermal diffusivities were analyzed. The importance of parameterizing the thermal diffusivity in the phase transition zone of ice under the trend of global warming was illustrated. Future research ideas on the physical mechanism, application value, and parameterization scheme of the thermal diffusivity of natural ice were envisaged.

This Special Issue aims to highlight research articles focusing on the geographical scale of glacier and lake ice variations, as well as the engineering scale of ice properties and their practical applications via laboratory tests and numerical modeling. Additionally, it includes research on ecosystems under lake ice. The main goal is successfully achieved through the joint efforts of authors, anonymous reviewers, and editorial managers. In total, 1 review article and 15 research articles are included in this Special Issue. These articles cover a wide range of topics, including water resources from Chinese mountain glacier variation; lake ice phenology at different latitudes and altitudes around the world; ice properties from laboratory experiments and numerical modeling; ice engineering with different purposes in China and the Arctic; and ecosystem under lake ice at different temporal and spatial scales. This Special Issue received contributions from researchers from different parts of China and from Chinese international cooperation partners because of its focus on “higher temperature ice” under global warming. All papers presented are innovative and of high quality. This Special Issue can promote research on ice properties and their applications in practices ranging from mountains to sea, especially in popular water ecosystem environments under ice during seasonal ice period.

Chlorophyll is an important component of crop photosynthesis as it is necessary for the material exchange between crops and the atmosphere. The amount of chlorophyll present reflects the growth and health status of crops. Spectral technology is a feasible method for obtaining crop chlorophyll content. The first-order differential spectral index contains sufficient spectral information related to the chlorophyll content and has a high chlorophyll prediction ability. Therefore, in this study, the hyperspectral index data and chlorophyll content of soybean canopy leaves at different growth stages were obtained. The first-order differential transformation of soybean canopy hyperspectral reflectance data was performed, and five indices, highly correlated with soybean chlorophyll content at each growth stage, were selected as the optimal spectral index input. Four groups of model input variables were divided according to the following four growth stages: four-node (V4), full-bloom (R2), full-fruit (R4), and seed-filling stage (R6). Three machine learning methods, support vector machine (SVM), random forest (RF), and back propagation neural network (BPNN) were used to establish an inversion model of chlorophyll content at different soybean growth stages. The model was then verified. The results showed that the correlation coefficient between the optimal spectral index and chlorophyll content of soybean was above 0.5, the R2 period correlation coefficient was above 0.7, and the R4 period correlation coefficient was above 0.8. The optimal estimation model of soybean and chlorophyll content is established through the combination of the first-order differential spectral index and RF during the R4 period. The optimal estimation model validation set determination coefficient (R2) was 0.854, the root mean square error (RMSE) was 2.627, and the mean relative error (MRE) was 4.669, demonstrating high model accuracy. The results of this study can provide a theoretical basis for monitoring the growth and health of soybean crops at different growth stages.

Unfrozen free and non-free water between ice crystals in flat and hummock ice in the Yellow River exists as water films with varying contents based on ice temperature. These contents can affect the radar wave velocity of the ice despite its theoretical dependence on the crystal structure and ice body components. The unfrozen water content in ice depends on the ice temperature, which is controlled by the air temperature, solar radiation, and ice thickness. Winter air temperature and radar-detected ice thickness data observed at the Shisifenzi bend in the Yellow River from 2020 to 2021 were analyzed. The unfrozen water content in the ice was the primary factor influencing the accuracy of flat ice thickness detection. The heat flux at the ice–water interface in the Yellow River was determined. The evolution of ice thickness and temperature were simulated using a one-dimensional (1D) ice thermodynamic model forced by the local weather station data (i.e., air temperature, solar radiation, wind speed, and cloud cover). On this basis, the measured ice thickness data of 13 drill holes were combined to calculate 1251 thermodynamically simulated ice thicknesses consistent with the ice thickness detection time of the radar; therefore, statistical relationships regarding the influence of air temperature and the combined action of air temperature and ice thickness on the radar wave velocity in granular and columnar ice during air temperature increases and decreases were determined. Finally, the statistical relationship between the combined influence of air temperature and ice thickness on radar wave velocity was selected as a parameterization scheme to dynamically correct the radar wave velocity of flat ice. To enhance the radar detection accuracy for flat ice thickness, the radar wave velocity of ice was parameterized as a function. Given the presence of unfrozen frazil ice and accumulated broken ice blocks in the Yellow River, radar is suggested to detect the thickness of different types of ice in future research.

In dryland agriculture, mulching methods and nitrogen application have been extensively adopted to improve water and nitrogen use efficiency and increase crop yield. However, there has been a scarcity of research on the combined effects of mulching types and nitrogen application on the growth and yield of soybean (Glycine max L.). In the present study, four nitrogen levels (N0: 0 kg N ha−1, N1: 60 kg N ha−1, N2: 120 kg N ha−1, N3: 180 kg N ha−1) and four mulching methods (NM: no mulching, SM: straw mulching, FM: film mulching, SFM: straw and film mulching) were set so as to evaluate the effects of mulching methods and nitrogen application on dry matter accumulation, grain yield, water-nitrogen use efficiency, and economic benefits of soybean in Northwest China from 2021 to 2022. The results show that the dry matter accumulation, yield formation, water and nitrogen use efficiency, and economic benefits of soybean were improved under different mulching methods (SM, FM, and SFM) and nitrogen applications (N1-N3), and that the effect is the best when the nitrogen application rate is N2 and the mulching method is FM. As such, a conclusion could be drawn that suitable nitrogen application (120 kg ha−1) combined with film mulching was beneficial for the utilization of rainwater resources and soybean production in the dryland of Northwest China.

Valid factors to evaluate the prognosis of triple-negative breast cancer (TNBC) with residual disease after neoadjuvant chemotherapy (NAC) are still lacking. We performed this study to explore prognostic factors focusing on genetic alterations and clinicopathology features in non- pathologic complete response (pCR) TNBC patients. Patients initially diagnosed with early-stage TNBC, treated with NAC, and who had residual disease after primary tumor surgery at the China National Cancer Center during 2016 and 2020 were enrolled. Genomic analyses were performed by targeted sequencing for each tumor sample. Univariable and multivariable analyses were conducted to screen prognostic factors for the survival of patients. Fifty-seven patients were included in our study. Genomic analyses showed that TP53 (41/57, 72%), PIK3CA (12/57, 21%), and MET (7/57, 12%), and PTEN (7/57, 12%) alternations commonly occurred. The clinical TNM (cTNM) stage and PIK3CA status were independent prognostic factors of disease-free survival (DFS) (p < 0.001, p = 0.03). A prognostic stratification indicated that patients with clinical stages I &II possessed the best DFS, followed by those with clinical stage III & wild-type PIK3CA. In contrast, patients with clinical stage III & the PIK3CA mutation had the worst DFS. In TNBC patients with residual disease after NAC, prognostic stratification for DFS was observed by combining the cTNM stage and PIK3CA status.

Continuous memristors have been widely studied in recent years; however, there are few studies on discrete memristors in the field of neural networks. In this paper, a four-stable locally active discrete memristor (LADM) is proposed as a synapse, which is used to connect a two-dimensional Chialvo neuron and a three-dimensional KTZ neuron, and construct a simple heterogeneous discrete neural network (HDNN). Through a bifurcation diagram and Lyapunov exponents diagram, the period and chaotic regions of the discrete neural network model are shown. Through numerical analysis, it was found that the chaotic region and periodic region of the neural network based on DLAM are significantly improved. In addition, coexisting chaos and chaos attractors, coexisting periodic and chaotic attractors, and coexisting periodic and periodic attractors will appear when the initial value of the LADM is changed. Coupled by a LADM synapse, two heterogeneous discrete neurons are gradually synchronized by changing the coupling strength. This paper lays a good foundation for the future analysis of LADMs and the related research of discrete neural networks coupled by LADMs.

To solve the problem of longitudinal cooperative formation driving control of multiple vehicles, a model-free adaptive control algorithm with constraints (cMFAC) is proposed in this paper. In the cMFAC algorithm, a dynamic linearization technique with a time-varying parameter pseudo-gradient (PG) is used to linearize the multivehicle collaborative system. Then, a cMFAC controller is designed. The algorithm sets the input and output constraints at the same time to prevent the vehicle speed and other parameters from exceeding the specified range. The main advantage of the cMFAC algorithm is that the entire control process only needs the input and output data of each vehicle and can effectively handle the input and output constraints. In addition, the stability of the cMFAC method is verified through strict mathematical analysis, and its effectiveness is verified with semi-physical experiments based on a MATLAB/Simulink module and CarSim platform connection environment. It is worth noting that the proposed cMFAC controller is symmetric because the input cost function and PG cost function have symmetric and similar structures, and the forms of the two cost functions are the same.

Understanding the spatial distributions of soil water, temperature and nutrients as well as their effects on maize growth and grain yield is vital for optimizing drip fertigation regimes. In this study, a 2 year field experiment was conducted on drip-fertigated spring maize with plastic mulching in arid northwestern China in 2015 and 2016. Four irrigation levels were set: as I60 (60% ETc; ETc is crop evapotranspiration), I75 (75% ETc), I90 (90% ETc) and I105 (105% ETc) in 2015; and as I60 (60% ETc), I80 (80% ETc), I100 (100% ETc) and I120 (120% ETc) in 2016. Two fertilization rates of N-P2O5-K2O were set: as F180 (180-90-90) and F240 (240-120-120). The results showed that the average soil water content in the deeper soil layer (80–120 cm) increased with the increase in irrigation level, and the lowest average soil water content in the 0–80 cm soil layer occurred under I95 in 2015 and under I100 in 2016. The irrigation level more significantly influenced the soil temperature at 5 cm than at the other depths. With the decrease in the irrigation level and progression of the growth period, the soil temperature increased. The soil nitrate nitrogen content in the root zone decreased with increasing irrigation level. The largest soil nitrate nitrogen content at the 0–100 cm depth occurred under I60 in both 2015 and 2016. Significant differences were observed for root length density in the 0–20 cm soil layer at various lateral locations. In deeper (60–100 cm) soil layers, the root length density under I75 (2015) and I80 (2016) was greater than at other depths. Grain yield, water use efficiency (WUE) and partial factor productivity (PFP) increased with the increase in irrigation level in 2015, while it increased and then decreased in 2016. I105F180 achieved the maximum grain yield (18.81 t ha−1), WUE (3.32 kg m−3), and PFP (52.26 kg kg−1) in 2015, while I100F180 achieved the maximum grain yield (20.51 t ha−1), WUE (3.99 kg m−3), and PFP (57.02 kg kg−1) in 2016. The optimal drip fertigation regimes for spring maize in arid northwest China were recommended as 90–100% ETc and 180-90-90 (N-P2O5-K2O) kg hm−2.

In order to enrich the dynamic behaviors of discrete neuron models and more effectively mimic biological neural networks, this paper proposes a bistable locally active discrete memristor (LADM) model to mimic synapses. We explored the dynamic behaviors of neural networks by introducing the LADM into two identical Rulkov neurons. Based on numerical simulation, the neural network manifested multistability and new firing behaviors under different system parameters and initial values. In addition, the phase synchronization between the neurons was explored. Additionally, it is worth mentioning that the Rulkov neurons showed synchronization transition behavior; that is, anti-phase synchronization changed to in-phase synchronization with the change in the coupling strength. In particular, the anti-phase synchronization of different firing patterns in the neural network was investigated. This can characterize the different firing behaviors of coupled homogeneous neurons in the different functional areas of the brain, which is helpful to understand the formation of functional areas. This paper has a potential research value and lays the foundation for biological neuron experiments and neuron-based engineering applications.

To investigate the effects of high-temperature stress on the chlorophyll fluorescence induction kinetics of peony and to determine indicators for the rapid screening of varieties responding to high temperatures, three four-year-old peony variety, ‘Fengdanbai’, ‘Huhong’, and ‘Yinhongqiaodui’, were selected as materials. The photosynthetic curves (Pn-PAR) and fast chlorophyll fluorescence curves (OJIP curves) of peony leaves were measured at different times under high-temperature stress conditions (40 °C), the changes in the photosynthetic characteristics of different peony varieties under high-temperature stress were analyzed, and the heat tolerance of peony was evaluated. The results showed that ‘Huhong’ grew well within 16 days, while all of the other varieties showed obvious wilting at 6–9 days. High temperatures damaged the structure and function of the photosystem of peony leaves, indicating that the maximum net photosynthetic rate (Pnmax), apparent quantum efficiency (AQE), maximum photochemical efficiency (Fv/Fm), and photosynthetic performance index (PIABS) all tended to decrease under high-temperature stress, while the rate of closing the PS II reaction center (Mo) and the absorption per reaction center (ABS/RC), the capture (TRo/RC), and the dissipation (Dio/RC) of light energy per reaction center showed an overall increasing trend. The ability to cope with high-temperature stress differed among varieties, and the heat tolerance was determined to be in the descending order of ‘Fengdanbai’ < ‘Yinhongqiaodui’ < ‘Huhong’. The correlation analysis among the parameters and the analysis of the morphological change patterns in peony leaves concluded that PIABS, Dio/RC, and Mo could be used as indicators of peony tolerance to high-temperature stress. The results of the study can provide a basis for the screening of heat-tolerant peony species and peony heat defense in the Jiangnan area.

Abstract This letter presents a novel locally active memristor with four‐stable pinched hysteresis loops which has never been reported before. The non‐volatile memory and local activity of the memristor are verified by the power‐off plot and DC V–I plot. A memristive Hindmarsh–Rose (HR) neuron model is constructed by employing the proposed memristor to characterize the electromagnetic induction effect on the membrane potential. Co‐existing multiple firing patterns are explored under different memristor initial states. Interestingly, the firing rhythms of the neuron model can be regulated by adjusting the memristor initial values in different stable regions. Circuit simulations are included to verify the theoretical analysis.

Abstract Inertial weight adaptive quantum particle swarm optimization (DCWQPSO) algorithm can effectively improve the problem of particle falling into local extreme value. But the particle is still possible to fall into local extreme value in the later stage of particle evolution. When it is applied to photovoltaic multi‐peak maximum power tracking (MPPT), the tracking efficiency is not only reduced, but also may lead to tracking failure under the condition of sudden tracking of photovoltaic light intensity. To solve the above problems, this paper proposes a photovoltaic maximum power tracking (MPPT) control algorithm combining Lévy flight strategy with DCWQPSO algorithm. Lévy flight is a non‐Gaussian random process. The algorithm introduces Lévy flight strategy to change the mutation formula of particles and uses the characteristics of Lévy flight short step and occasionally long step jump search to improve the diversity of particles in the algorithm population. The algorithm proposed in this paper enhances the particle diversity, improves the convergence accuracy and speed of the algorithm, and overcomes the defects of the DCWQPSO algorithm. Simulation results demonstrate that the MPPT control algorithm proposed in this paper has fast‐tracking speed and high precision, which can effectively improve the maximum power tracking efficiency and dynamic quality of photovoltaic power generation system under uncertain environment, and it also has good robustness.

Positive leader inception under different rates of voltage rise is a key element in physical modeling of dielectric breakdown of long air gaps and evolution of natural lightning. The leader inception phase comes first in long-air-gap discharge, including first corona, primary dark period, and second corona, which is also called “leader corona,” portending leader inception. The Les Renardières Group has stated that the primary dark period is determined by the electrode curvature, based on which no leader inception model currently in use considers the influence of the rate of the applied voltage. To determine whether that assertion is true, an experimental scheme is designed so that impulse voltages can be applied with a large range of rise rates. With an increasing rate of voltage rise, the test results clearly show the following: (i) the curves relating the injected charge and inception voltage of the first corona present regular differences; (ii) the duration of the primary dark period decreases exponentially; (iii) the leader inception voltage and the difference between the leader and first-corona inception voltages present decreasing trends. These findings indicate that the formation of the dark period is related to more than just the electrode curvature, which is just one cause but may not be the essential reason for the dark period. The present findings suggest that the rate at which the applied voltage rises impacts the physical process of the streamer-to-leader transition during the dark period.

After large-scale sand fracturing of horizontal wells in shale gas reservoir, fracturing fractures will deform in the production process. However, fracture deformation will lead to the decrease in fracture conductivity and then cause the decrease of gas well productivity. Therefore, in order to evaluate the fracturing fracture deformation mechanism of shale reservoirs, the shale proppant-supported fracture deformation evaluation experiments were carried out under different proppant types, particle sizes, sanding concentrations, and closure pressure conditions, respectively, and the variation curves of fracture width was calculated by a stereomicroscope under different experimental conditions. Then based on the experimental results, the fracture sensitivity factors and fracture deformation mechanism were analyzed, and the deformation mechanisms of fracturing fractures affected by proppant embedding and crushing were studied emphatically. The analysis results of fracture sensitivity factors indicate that the larger the particle size and hardness of proppant, the lower the sand concentration, proppant embedded on the shale rock surface. Moreover, the deeper the proppant is embedded, the faster the fracture conductivity decreases. In addition, the greater the closure pressure, the more serious is the proppant embedment, and the faster the fracture width decreases. The analysis results of fracture deformation mechanism show that, on the on hand, under variable closure pressure, the proppant with larger hardness and larger particle size is used for fracturing, and the proppant embedded in the fracture surface is the main cause of fracture deformation. However, if only the sand concentration of the proppant in the fracture is changed, the fracture deformation is jointly dominated by the embedding and crushing of the proppant. On the other hand, under constant closure pressure, the main mechanism of fracture deformation is that the proppant is embedded into the fracture surface when the closure pressure is low, but if the closure pressure is high, the main mechanism of fracture deformation is the crushing and compaction of proppant.

Background. Accurate interpretation of lung function tests requires appropriate spirometry reference values derived from large-scale population-specific epidemiological surveys. The aim of this cross-sectional study was to establish normal spirometric values for the population of healthy, nonsmoking Han Chinese adults residing in Zhejiang province, China. Methods. We measured lung function parameters such as forced expiratory volume in 1 s, forced vital capacity, peak expiratory flow, maximal midexpiratory flow, and diffusion capacity for carbon monoxide and considered age, height, and weight as independent factors that may modify these parameters. The clinical data were divided into the study arm and validation group. The study arms were used to construct predictive equations using stepwise multiple linear regression, and data from the validation group were used to assess the robustness of the equations. Results. The 3866 participants were randomized into a study arm (n = 1,949) and a validation arm (n = 1,917). Lung function parameters had a negative association with age and a positive association with height. Data from the two groups were similar. Predictive equations were constructed from the study arm, and the validation group was used to test the feasibility of the reference equations. Conclusions. The reference values we derived can be used to evaluate lung function in this cohort in both epidemiological studies and clinical practice.

Abstract Background Autism spectrum disorder (ASD) is becoming increasingly prevalent of late. Methylenetetrahydrofolate reductase (MTHFR) has a significant role in folate metabolism. Owing to the inconsistencies and inconclusiveness on the association between MTHFR single nucleotide polymorphism (SNP) and ASD susceptibilities, a meta-analysis was conducted to settle the inconsistencies. Methods For this meta-analysis, a total of 15 manuscripts published up to January 26, 2020, were selected from PubMed, Google Scholar, Medline, WangFang, and CNKI databases using search terms “MTHFR” OR “methylenetetrahydrofolate reductase” AND “ASD” OR “Autism Spectrum Disorders” OR “Autism” AND “polymorphism” OR “susceptibility” OR “C677T” OR “A1298C”. Results The findings of the meta-analysis indicated that MTHFR C677T polymorphism is remarkably associated with ASD in the five genetic models, viz., allelic, dominant, recessive, heterozygote, and homozygote. However, the MTHFR A1298C polymorphism was not found to be significantly related to ASD in the five genetic models. Subgroup analyses revealed significant associations of ASD with the MTHFR (C677T and A1298C) polymorphism. Sensitivity analysis showed that this meta-analysis was stable and reliable. No publication bias was identified in the associations between MTHFRC677T polymorphisms and ASD in the five genetic models, except for the one with regard to the associations between MTHFRA1298C polymorphisms and ASD in the five genetic models. Conclusion This meta-analysis showed that MTHFR C677T polymorphism is a susceptibility factor for ASD, and MTHFR A1298C polymorphism is not associated with ASD susceptibility.