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[Objective] The study aims to elucidate the characteristics and cytological mechanisms of fertilization in the evolutionary special group of fern Lygodium japonicum . [Methods] Using embedding and electron microscopy techniques, ultrastructural observation was performed on the stage of sperm entry into the egg, nuclear fusion, egg expansion, and zygote polarity establishment during the fertilization process of L. japonicum . [Results] L. japonicum didn􀆳t have the typical egg envelope and fertilization pore, and spermatozoa penetrated the egg through the pore region. The first spermatozoon entered the cytoplasm of the egg, and 2-6 spermatozoa could also pass through the pore region to enter the fertilization cavity below the pore region of the egg, but could not fuse with the egg cytoplasm. After sperm entered the egg, the fertilized egg shrinked markedly to prevent the entry of other sperms, and a membrane structure was formed at the pore region above the fertilization cavity, blocking the entry of other sperms into the fertilization cavity. Nuclear fusion was initiated 30 min after spermatozoa entered the egg cell. The nucleus of spermatozoa was initially concentrated at one end of the nucleus and gradually penetrated into the nucleus of the egg, and nuclear fusion continued as the fertilized egg were expanding. Around 10 h after fertilization, the zygote produced a large number of vesicles, which first established vertical polarity and then changed to horizontal polarity, and underwent the first division of the zygote. [Conclusion] When L. japonicum undergoes fertilization, spermatozoa enters from the pore region and produces a fertilization cavity, similar to the core leptosporangiatae.

Improving the power generation efficiency of coal-fired units is an effective measure to achieve energy conservation and carbon reduction. The engineering application of 700 ℃ ultra-supercritical coal-fired power generation is hindered by the high price of superalloy materials; therefore, it is necessary to explore new layouts and structures to shorten the high-temperature steam pipelines and reduce the engineering costs. By taking the phase III expansion project—the world’s first demonstration project of high-level layout—of the Jinjie coal-fired power plant as an example, this study introduces the engineering innovation practice of the high-level layout technology for an air-cooled ultra-supercritical steam-turbine generator unit. The results indicate that the reinforced concrete frame and shear wall structure can effectively lower the overall center of gravity and improve the seismic performance of the main power house,thereby ensuring the safety of the main power house structure, high-temperature steam pipelines, and steam turbine generator unit through technological breakthroughs. Compared with those of the conventional layout (its operating floor level being 12.6‒17 m), the main steam and reheat steam pipelines of the high-level layout (its operating floor level being 65 m) can save 34.2% and 20.9% of raw materials,respectively; and exhaust steam pipes of the air-cooled island can save 93% of raw materials. Furthermore, the power supply coal consumption can be reduced by 4.5‒5.1 g/(kW·h) compared with the design value, and the overall economical efficiency is significantly improved. The monitoring data after operation show that all parameters in the real-time on-line monitoring system of the main power house structure are within the safety threshold, and the plant structure and critical equipment are both in a safe state. Therefore, we propose to promote clean and efficient coal-fired power generation technologies and apply the high-level layout technology to the advanced air-cooled coal-fired power units in northeast, north, and northwest China as these regions are rich in coal but short of water. This can provide practical experience for the construction of economical high-temperature steam pipelines for 700 ℃ ultra-supercritical coal-fired power units.

Genetic susceptibility, inflammatory mechanism and unhealthy lifestyle are associated with increased risk of hypertension, a common chronic cardiovascular disease, and asthma, a common chronic respiratory disease. The research on the pathogenesis and management of hypertension with bronchial asthma has become a hotspot recently. We did a review of the latest relevant studies on hypertension and bronchial asthma. It was concluded that the co-morbidity of hypertension and asthma was related to common genetic disorders, systemic inflammation and poor lifestyle. Then gave a summary of the interaction mechanism between the two diseases and related management methods. Calcium channel blockers and angiotensin receptor antagonists were recommended as the first choice for drug treatment. This study aims at offering insights into clinical research on the pathogenesis and scientific management of hypertension with asthma.

The incidence of endometrial cancer (EC) increases annually and tends to occur in younger women. A particularly important relationship exists between EC and metabolic disorders. As one of the most important components of lipid metabolism, phospholipids play an indispensable role in metabolic balance. LPCAT1 is a key enzyme regulating phospholipid metabolism. In this study, we perform further investigations to seek mechanistic insight of LPCAT1 in EC. Our results demonstrate that silencing of LPCAT1 inhibits the growth of endometrial cancer, while overexpression of LPCAT1 results in enhanced stemness and metastasis in endometrial cancer cell lines. Meanwhile, the contents of various phospholipids including phosphatidylethanolamine (PE), phosphatidylcholine (PC), and triglyceride (TG) change significantly after overexpression of LPCAT1. In addition, through RNA-sequencing and western blot analysis, we observe that the TGF-β/Smad2/3 signaling pathway is of great importance in the tumor-promoting function of LPCAT1. LPCAT1 promotes the expressions of stem cell-related transcription factors and epithelial-mesenchymal transition (EMT) related proteins through the TGF-β/Smad2/3 signaling pathway. Moreover, we find that TSI-01, which can inhibit the activity of LPCAT1, is able to restrain the proliferation of EC cell lines and promote cell apoptosis. Collectively, we demonstrate that LPCAT1 enhances the stemness and metastasis of EC by activating the TGF-β/Smad2/3 signaling pathway and that TSI-01 may have potential use for the treatment of EC.

Alternative splicing is a key step in the regulation of post-transcriptional gene expression, and its dysfunction is closely related to tumorgenesis. This review systematically describes the regulation, specific events and development of prognostic model of alternative splicing in oral squamous cell carcinoma, to provide a new idea for the exploration of targeted therapy on oral squamous cell carcinoma.

Copolymerization of acrylonitrile (AN) with hydrophilic monomers is one of the research directions in the preparation of fouling-resistant polymeric materials. In this study, poly(acrylonitrile-co-maleic acid) copolymer (P(AN-co-MA)) membranes were prepared by 60Co γ-ray-induced copolymerization of AN and MA in a dimethyl sulfoxide (DMSO)/water mixed solvent. A phase inversion method was then applied. The effects of the solvent on the monomer conversion and molecular weight of the copolymer were investigated. The dependence of porosity, hydrophilicity, Zeta potential, and anti-fouling properties of the copolymer membranes on the molar feed ratio of maleic anhydride (MAH) was also studied. The results showed that in the DMSO/water mixed solvent under a mass ratio of 3∶2, the monomer conversion rate could reach over 80%, and the molecular weight of the obtained copolymer was close to 220 000. The porosity and hydrophilicity of the copolymer membrane increased with an increase in the molar feed ratio of MAH. The adsorption capacity of the copolymer membrane under a molar feed ratio of MAH of 30% for bovine serum albumin was only 52.1% of that of the polyacrylonitrile (PAN) homopolymer membrane. This study provides a useful reference for preparing PAN-based anti-fouling membranes with a controllable structure and properties using a radiation technique.

The copolymerization of acrylonitrile (AN) with a hydrophilic monomer is an effective way to prepare hydrophilic polyacrylonitrile (PAN)-based functional materials. In this study, γ-ray radiation-induced copolymerization of AN and 4-vinylpyridine (4-VP) in dimethylsulfoxide (DMSO) was carried out. The chemical structure, molecular weight, thermal properties, and hydrophilicity of the synthesized copolymers were characterized. The γ-ray radiation could initiate the copolymerization of AN and 4-VP in DMSO at room temperature (0~35 ℃). The monomer conversion reached above 90% at the absorbed dose of 25 kGy, but the molecular weight of the copolymer depended on the dose rate. When the absorbed dose was 30 kGy, a P(AN-co-4-VP) random copolymer solution with a viscosity of 250 Pa⸱s was obtained directly after the monomer solution was irradiated by γ-rays at a lower dose rate of 11 Gy/min. The P(AN-co-4-VP) copolymer had a weight-average molecular weight of 1.34×105, and the relative content of AN and 4-VP units in the copolymer chains was identical to the feed ratio of AN and the 4-VP comonomer. When the dose rate exceeded 20 Gy/min, molecular weight of the synthesized copolymer decreased remarkably. Thermal properties of the P(AN-co-4-VP) random copolymer with the relative molar ratio of 4-VP to AN of 2% were generally the same as those of the PAN homopolymer. The 4-VP units in the polymer chains did not participate in the ring formation or crosslinking reaction of the side ‒C≡N groups. However, the water contact angle of the P(AN-co-4-VP) random copolymer decreased gradually with increase in 4-VP content, indicating that the introduction of 4-VP units can improve the hydrophilicity of the copolymers. This study provides a new idea for the hydrophilic modification of PAN as well as proves that DMSO solutions with a high mass fraction (>20%) of the homo- or copolymer of AN can be obtained directly via radiation-induced solution polymerization, thus expanding the potential applications of the high-energy radiation technique in the field of solution polymerization of AN.

BackgroundFatigue risk management for pilots has received increasing attention. The existing fatigue management systems have detailed descriptions of the factors and the mutual influences among the factors that affect the dimension of “sleep”, which is one of the most important causes of fatigue. However, the analysis of the influencing factors of the “work” dimension of fatigue causes has not been very detailed or accurate, especially the exploration of the mutual influence among many fatigue-influencing factors in the “work” dimension.ObjectiveThe purpose of this study was to explore the mutual influence among fatigue-influencing factors related to the “work” dimension in the analysis of pilot fatigue causes.MethodsThis study designed a questionnaire on the dimension of “work” in the causes of pilot fatigue and collected a total of 270 feedback data points from international flight pilots. Based on the questionnaires and data, descriptive statistical analysis, exploratory factor analysis and confirmatory factor analysis were performed to explore the influencing factors and their mutual influences on the “work” dimension of pilot fatigue.ResultsThere is a strong, mutual influence relationship among the fatigue causes of long-haul flight pilots – working status, working conditions and working schedules – in the dimension of “work”. The workload only has a strong correlation with the working schedule, and the interaction relationships with the working status or working conditions are weak.ConclusionThis study analyses the mutual influence among the influencing factors of the “work” dimension of pilot fatigue, and we expect to provide empirical data for pilot fatigue risk management and to help improve fatigue risk management systems.

Artificial nanostructures in metasurfaces induce strong spin–orbit interactions (SOIs), by which incident circularly polarized light can be transformed into two opposite spin components. The component with an opposite helicity to the incident light acquires a geometric phase and is used to realize the versatile functions of the metasurfaces; however, the other component, with an identical helicity, is often neglected as a diffused background. Here, by simultaneously manipulating the two spin components originating from the SOI in plasmonic metasurfaces, independent wavefields in the primary and converted spin channels are achieved; the wavefield in the primary channel is controlled by tailoring the dynamic phase, and that in the converted channel is regulated by designing the Pancharatnam–Berry phase in concurrence with the dynamic phase. The scheme is realized by generating optical lattice fields with different topologies in two spin channels, with the metasurfaces composed of metal nanoslits within six round-apertures mimicking the multi-beam interference. This study demonstrates independent optical fields in a dual-spin channel based on the SOI effect in the metasurface, which provides a higher polarization degree of freedom to modify optical properties at the subwavelength scale.

BackgroundDietary restriction therapy is one of the new methods of tumor treatment following surgery, radiotherapy and chemotherapy, and it plays an important role in the treatment of various tumors. However, there are no studies on the safety of this therapy.PurposeThis study aims to evaluate the effect of dietary restriction therapy on the body and to screen a safe dietary restriction therapy.MethodFirst of all, twenty mice were used for 45 days of food intake testing after 1 week of adaptive feeding. Secondly, sixty mice were randomly divided into 4 groups, one was taken Ad-libitum fed (AL) and 3 groups were treated by three dietary restrictions, i.e., 50% daily dietary restriction (DR), alternate-day fasting (ADF), alternate-day 50% dietary restriction (ADR). Daily food intake of normal mice was checked and the effects of three dietary restrictions on weight and survival time were evaluated. The liver and kidney function was tested on the collected serums of these mice to screen out the optimal dietary restriction scheme. Then, synchrotron-based hard X-ray fluorescence microscopy was used to test the biodistribution of several trace elements in liver and kidney for the safety evaluation of the optimal dietary restriction scheme. Haematoxylin and eosin (H&E) staining was employed to test whether the organs and tissues had lesions.ResultsExperimental results show that the average daily food intake of the mice is 0.2 g per gram of body weight. The body weight of the mice treated with 50% daily dietary restriction decreases linearly, and the survival time is significantly shortened; alternate-day fasting results in significant weight loss, shortened survival time and abnormal liver and kidney function whilst alternate-day 50% dietary restriction has no significant changes in body weight, survival time, liver and kidney function, and the biodistribution of trace elements in liver and kidney, and the pathology of major organs.ConclusionA safe dietary restriction scheme developed in this study will provide theoretical and experimental basis for the adjuvant treatment of malignant tumors with dietary restriction therapy.

【Objective】 The purpose of the study is to determine the appropriate irrigation water salinity threshold for winter wheat. Correlation analysis was conducted to find out the important growth, physiological and biochemical indexes related to wheat yield under different saline water irrigation. 【Method】 The pots experiment was conducted in 2019/20 season with two winter wheat varieties of SM22 and XY60 and four irrigation water salinities of 1 g/L, 3 g/L, 5g/L and 7 g/L. Irrigation water salinity with 1 g/L was taken as the control (CK). During the experiment, we measured the changes in yield, of wheat, as well as its physiological and biochemical traits in each treatment. 【Result】 The yield of both wheat varieties decreased as irrigation water salinity increased though at different rates. Compared with the CK, irrigating with saline water at concentration of 3, 5 and 7 g/L reduced the yield of SM22 by 3.23%, 24.19% and 51.61% respectively, and the yield of XY60 by 9.88%, 35.80% and 51.85% respectively. In terms of plant traits, increasing irrigation water salinity reduced the spike number and 1 000-kernel weight, plant height, flag leaf area, above- and below-ground biomasses, stomatal conductance, transpiration rate, net photosynthesis rate, chlorophyll content (SPAD) of the flag leaf, K+/Na+, Ca2+/Na+ and Mg2+/Na+ ratios in the leaves during grain-filling stage. All these reductions were at significant level. In contrast, it increased the proline content and Na+ content in leaves during the grain-filling period at significant level. In all treatments, the wheat yields were to be positively correlated to the following traits at significant level (p

The meshing transmission part of the cycloidal pin wheel is the key structure of the RV reducer，the simulation analysis of virtual prototype based on multi-body dynamics is a common method to study the dynamic characteristics of the RV reducer. Taking into account different loads and different working conditions，the RV reducer is simulated and analyzed based on multi-rigid dynamics. The simulation results visually show the changes of the meshing characteristics of the cycloidal pin teeth under different working conditions. The rigid-flexible coupling technique is used to extract the continuous node stress curve for analysis，and the position and size of the maximum contact force during meshing are determined，and a theoretical basis for the research and improvement on the way of subsequent shaping is provided.

Guided bone regeneration (GBR) barrier membranes are of great significance for the reconstruction of the health and function of different periodontal tissues. Biocompatibility, spatial maintenance, closure, controllability and biological activation are the main criteria that should be met by these membranes. Artificial barrier membrane biomaterials can be divided into synthetic polymer materials, natural polymer materials and metals. According to their degradation characteristics, these membranes can be divided into two categories, absorbable and nonabsorbable membranes. GBR used for horizontal bone increments can be used to treat various types of bone defects, including the treatment of bone fenestration and bone cracking. The use of a non-absorbable e-PTFE membrane or absorbable collagen membrane can achieve the expected effect. However, for incremental or vertical bone growth at the alveolar crest, the use of this membrane is very challenging and requires good strength to maintain the osteogenic space. This space can be enhanced with e-PTFE or d-PTFE membranes with stable morphology, or absorbable membranes can be covered with titanium plates or meshes to achieve vertical bone increments. Currently, bioactive membranes, digital 3D-printed titanium membranes and piezoelectric active biological membranes are research hotspots. In future research, the biological activation of these membranes will be further improved, which will promote the development of artificial membranes in the next stage.

In the underground catalytic gasification process of lean coal, the solid catalyst cannot be used and recovered, so it is necessary to develop an inexpensive liquid catalyst.In order to explore the feasibility of seawater as a cheap gasification agent for underground coal gasification, and to understand the catalytic effect of NaCl component on coal pyrolysis and gasification, this paper selects the block size with 3%NaCl solution (simulated seawater) as catalyst.The lean coal of Wangxie Coal Mine of about 6cm was subjected to pyrolysis test.The heating rate inside and outside of the coal block and the composition of the pyrolysis product tar were measured.The influence of the catalyst on the semi-coke structure was studied.The results show that the temperature transfer in the process of pyrolysis of massive lean coal has hysteresis.The activation energy of large-scale coal with addition of NaCl catalyst in the temperature range of 350℃~650℃ is reduced by 39%and 45%, respectively, compared with the raw coal;catalytic pyrolysis The benzene content in tar increased by 7.8%, the hydrocarbon content of coal sample Ⅰ decreased by 14.9%, coal sample Ⅱ decreased by 32.4%;the specific surface area of catalytic pyrolysis coal char was significantly larger than that of non-catalyzed pyrolysis;The content of-OH bond and=C=O health coal Ⅱ coke < coal Ⅰ coke < raw coal.It can be concluded that seawater has a certain catalytic effect on coal pyrolysis and gasification.

The excessive emission of NO is endangering the ecological environment and the health of humans. In-depth research on the reduction mechanisms of NO is crucial to regulating NO emissions. In this research, the influence of sodium on the heterogeneous reaction of NO by semichar derived from O2/CO2 pretreatments were investigated through the experimental and density functional theory (DFT) method. According to the results of atomic dipole corrected Hirshfeld atomic charge (ADCH), the additional Na and oxygen-containing compound altered the semichar's charge distribution of. The additional Na weakened the positive effects of the marginal hydrogen. And the charge of the carbon, which was attached to the phenol group, changed from negative to positive due to the strong electron-trapping ability of the phenol group. The energy potential diagrams between NO and semichars derived from O2/CO2 pretreatments without/with sodium addition reflected that sodium was beneficial to reduce NO. Compared with pure O2/CO2 pretreatments, the additional sodium decreased the energy gap of the NO reduction by 144.68 kJ/mol. On the other hand, the temperature-programmed reduction (TPR) results were performed to identify the accuracy of the calculation results. The experimental results illustrated that adding sodium enhanced the NO reducibility of semichar, expressing great consistency with the theoretical results.

Thermally comfortable mircoclimate is essential for creating high-quality outdoor spaces that attract citizens and boost city vitality. Previous design efforts to improve outdoor thermal comfort were usually conducted at large scales, such as city scale, neighborhood scale, urban block scale. Few researchers focused on the building scale. This study proposes an optimization framework based on genetic algorithm to determine the building shape, orientation, and location during early design stage that reduces the overall thermal stress in the target outdoor space. Solar radiation and wind fields were simulated to obtain the outdoor Universal Thermal Climate Index (UTCI) as the performance indicator. The simulations were validated against the experimental data. This investigation applied the proposed optimization framework to design the outdoor space for a kindergarten under the climate of Tianjin and Shanghai, respectively. The results showed that optimization reduced the overall thermal stress. The most favourable kindergarten forms were suggested through optimization. This study supplements the inverse design of outdoor thermal comfort at building scale and provides suggestions to create comfortable urban outdoor spaces.

When constructing small clear-distance tunnels in complex geotechnical conditions, there are many challenges including intolerable ground movement, face failure, and potential damage to adjacent tunnel. This paper focused on the study of small clear-distance shield tunnel construction in the typical upper-soft and lower-hard stratum. Numerical analyses are conducted to estimate the influence of the new tunneling on the existing tunnel. In addition, partition wall accompanied by cement-soil mixing pile is adopted as the control measure. The results demonstrate that the construction of the new tunnel has a big impact on the stability of the existing tunnel. The seal roof block should not be placed on the top region. The obviously influenced region of the existing tunnel agrees with the excavation diameter of the new tunnel, so monitoring in this region should be strengthened. Moreover, the safety control effect has been verified by numerical analysis and field test. This study provides a basis for the design and construction of tunnels with shallow buried depths and small clear-distances.

Abstract Background To assess the efficacy of Nimotuzumab in combination with first-line chemoradiotherapy treatment in Chinese patients with primary III-IVb stage nasopharyngeal carcinoma. Methods Patients with primary locoregionally advanced nasopharyngeal carcinoma who were treated with intensity-modulated radiotherapy (IMRT) and concurrent cisplatin-based chemotherapy between January 2008 and December 2013 at a single institution were retrospectively reviewed. Group A received at least 6 doses of Nimotuzumab, while Group B did not receive Nimotuzumab. A propensity score matching method was used to match patients from each group in a 1:3 ratio. Results In total, 730 eligible patients were propensity matched, with 184 patients in Group A and 546 patients in Group B. Significant differences were not observed in the patient and tumor characteristics between Group A and Group B. At a median follow-up of 74.78 months (range 3.53–117.83 months), locoregional recurrence, distant failure and death were observed in 10.68, 11.10 and 16.03% of all patients, respectively. The estimated 5-year locoregional relapse–free survival, distant metastasis–free survival, progression-free survival and overall survival in the Group A versus Group B were 85.34% versus 89.79% (P = 0.156), 93.09% versus 85.61% (P = 0.012), 79.96% versus 77.99% (P = 0.117) and 88.91% versus 78.30% (P = 0.006), respectively. Conclusions This nimotuzumab-containing regimen resulted in improved long-term survival of III-IVb stage NPC patients and warrants further prospective evaluation.

Ecological restoration is important to mitigate global ecological degradation. However, previous restoration, mainly targeting a single ecosystem or ecological problem at a single scale, couldn’t effectively solve systemic ecological problems, especially in rapidly developing areas. Land-Space Ecological Restoration (LSER) policy was proposed to change the situation that traditional ecological restoration was lack of overall planning and united goals. To integrate ecological restoration measures in different departments and scales in LSER practice and management, a multi-scale evaluation framework for LSER planning strategy making based on “P-S-R” perspective and landscape, ecological, GIS methods was proposed, and applied in Jiangsu Yangtze River Economic Belt in China. We took fishnet scale as data calculation unit, and town, county, regional scales as decision scale to formulate a hierarchical evaluation and decision making system. In study area, ecological engineering type (including 7 kinds of protection or restoration, and artificial or natural measures) at town level was identified, guided by county-level LSER zoning and grading obtained by normal cloud model evaluation method. At regional scale, an ecological network including 53 ecological sources, 95 corridors, 674 restoration points, and 80 footstones was constructed to determine regional restoration priority. Based on the research results, a decision-making system could be formed, with the regional ecological network as the decision-making basis for the overall restoration pattern, the county-level LSER classification as the standard for planning goals and task decomposition, and the township LSER project classification as the basis for the site selection of diverse ecological restoration projects. The proposed evaluation framework could integrate the data and decision-making process of ecological restoration measures at different scales, and assist regional ecological goal setting and space strategy making of LSER planning to achieve sustainable development goals.

With the rapid development of copyright industry, people’s copyright awareness of their own creation of software and works is constantly improving, the number of applications for software copyright registration and works copyright is increasing. Therefore, how to make copyright registration business becomes more convenient and efficient is imminent. Existing copyright registration system need to first fill through PC and then make an appointment through the phone to deal with relevant business. This model is not only complicated operations, but also poor user experience. Therefore, based on the analysis of multiple needs of users and enterprises, this paper proposes to use Vue,SpringBoot, MyBatis and other technologies to develop a copyright appointment registration system based on microplatform. The development of this system can not only for the user to create a more convenient way of operation, give users a better experience, but also can change, rich business approach, bring more profits.