With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,t...With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,these technologies remain detached from rural teachers,failing to significantly enhance the quality of education and teaching in rural areas.Rural education is a crucial aspect of ensuring balanced development in education.The question of how to enhance rural teachers’technological application abilities and fully leverage the positive role of technology in rural education and teaching has become a significant topic of current research on rural education issues.To better address this question,this study conducted a thorough examination of the specific appeals of rural teachers in the process of technology enablement.It was discovered that rural teachers generally face dilemmas such as insufficient technological application abilities,difficulties in obtaining quality teaching resources,and the lack of continuous technical support and update mechanisms.Based on these findings,specific pathways such as strengthening rural teacher training,optimizing the allocation of educational resources,and establishing mechanisms for continuous technical support and updates are proposed to aid in the high-quality development of rural education.展开更多
The red beds of the northern Heyuan Basin (Guangdong Province, China) are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian F...The red beds of the northern Heyuan Basin (Guangdong Province, China) are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian Formation, and Zhenshui Formation of the Nanxiong Group, Shanghu Formation and Danxia Formation. The Nanxiong Group with relatively mature coarse clastic rocks attains about 2940 m in thickness. The Dafeng Formation is 837 m thick, consisting of conglomerates and sandy conglomerates; the Zhutian Formation, which is 1.200 m thick, consists of purplish red sandstone with gravels, poorly sorted sandstone, feldspathic quartzose sandstone banded granular conglomerate, siltstone, and sandy mudstone. The Zhutian Formation is rich in calcareous concretions. Heyuannia (Oviraptoridae) and turtle fossils were found in this formation. The Zhenshui Formation deposited to a thickness of 900 m consists of coarse sediments, including granular conglomerate, and gravelly sandstone with well developed cross-beddings; the Shanghu Formation, which is 820 m thick, consists of purplish red granular conglomerate coarse sandstone intercalated with fine si^tstone; the Danxia Formation characterized by the Danxia ~andform is composed of coarse c^astic gravels and sandy gravels. The lower part of the Nanxiong Group whence dinosaur eggs and derived oviraptorosaurs come, belongs to the Late Cretaceous. No fossils are found in the Shanghu Formation or the Danxia Formation, but their stratigraphic order of superposition on the Nanxiong Group clearly shows their younger age.展开更多
The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, ou...The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, outer surface texture, and shell thickness) of 461 eggs were analyzed using non-destructive techniques and subjected to statistical analyses in order to assess their diversity and taxonomic affinities. Three types (1, 2 and 3) of eggs were discerned based on shape and outer surface morphology. Type 1 eggs are spherical to ellipsoidal in shape and have a rough surface. Three subtypes (Type 1-A-l, l-A-2, and l-B) are apparent from scatter plots and cluster analyses of egg diameters and shell thickness. Type 2 eggs are elongate with linear ornamentation on the surface, and are comparable to eggs that belong to the oofamily Elongatoolithidae. Type 3 eggs are elongate with a smooth surface, and are assigned to the oofamily Prismatoolithidae. Macromorphological features of the various egg types suggest that Type 1 could have been laid by ornithischian, sauropod or therizinosaur dinosaurs, Type 2 by oviraptorids, and Type 3 by troodontids. This study represents the first comprehensive statistical analysis of macrofeatures of dinosaur eggs, and reveals taxonomic diversity in the dinosaurs that were laying eggs in the Upper Cretaceous Heyuan area heretofore unrecognized in skeletal remains.展开更多
A composite bone cement based onα-TCP with self-reinforcing characteristics is prepared by compounding cellulose whiskers and polyvinyl alcohol in different proportions.In this system,we are inspired by the sea cucum...A composite bone cement based onα-TCP with self-reinforcing characteristics is prepared by compounding cellulose whiskers and polyvinyl alcohol in different proportions.In this system,we are inspired by the sea cucumber,which can alter the stiffness of their inner dermis reversibly.Through the formation of hydrogen bonds between the hydroxyl groups on the cellulose whiskers and PVA,the bone cement matrix can be strengthened during the curing process of cement.In the process of bone cement blending,there is more water,the hydrogen bond connection is destroyed,so the slurry has better fluidity at this time.As the hydration of the bone cement progresses,the reduction of the water phase leads to the formation of a permeable network structure of hydrogen bond connections between the whiskers.The dual-phase action of PVA and whiskers greatly increases the mechanical strength of the bone cement system(5.5 to 23.8 MPa),while the presence of polyvinyl alcohol improves the toughness of the bone cement system.This work was supposed to explore whether the chemoresponsive materials can be adapted to biomedical materials,for example,bone repair.展开更多
Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which coul...Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which could be degraded by human digestive juice;while MLO 2-1 possessed the non-digestible property in the upper gastrointestinal tract and performed the function by regulating the gut microbiota.Hence,MLO 2-1 was selected for the further analysis.The structure of MLO 2-1 was elucidated as follow:α-T-Glcp-(1→3)-β-Glcp-(1→5)-α-Araf-(1→5)-α-Araf-1→5)-α-Araf-(1→3)-α-(2-OAc)-Glcp-1.The in vitro fecal fermentation results showed that MLO 2-1 could modulate the composition of gut microbiota.Meanwhile,MLO 2-1 was effectively metabolized by fecal bacteria to produce lactate and short chain fatty acids,especially acetate and butyrate.The specific metabolic pathways of MLO 2-1 by gut microbiota were further illuminated.Gut microbiota analysis revealed that MLO 2-1 selectively promoted the growth of Ligilactobacillus murinus,a commensal bacterium presented a reduced level in T2DM mice.Animal experiments indicated that MLO 2-1 and L.murinus exhibited hypoglycemic activities.These results demonstrated that MLO 2-1 might alleviate T2DM by selectively accelerating the proliferation of L.murinus.展开更多
Objective Most scholars agreed that the tectonic setting of South China block(SBC)changed from Tethys during the Indosinian to Pacific tectonic regime in the Yanshanian.However,the specific change time for the trans...Objective Most scholars agreed that the tectonic setting of South China block(SBC)changed from Tethys during the Indosinian to Pacific tectonic regime in the Yanshanian.However,the specific change time for the transition is still in debate and the Triassic to Jurassic magmatic activity will provide a clue to better understanding the transition.展开更多
OBJECTIVE To investigate the association between baseline hemoglobin A1c(HbA1c)levels and bleeding in patients with non-ST-segment elevation acute coronary syndrome(NSTE-ACS)who underwent percutaneous coronary interve...OBJECTIVE To investigate the association between baseline hemoglobin A1c(HbA1c)levels and bleeding in patients with non-ST-segment elevation acute coronary syndrome(NSTE-ACS)who underwent percutaneous coronary intervention(PCI).METHODS This observational cohort study enrolled 6283 consecutive NSTE-ACS patients undergoing PCI from January 1,2010 to December 31,2014.Based on baseline HbA1c levels,the patients were divided into the group with HbA1c<7%(n=4740)and the group with HbA1c≥7%(n=1543).The primary outcomes are major bleeding(BARC grades 3-5)and all-cause death during follow-up.RESULTS Of patients enrolled,4705(74.9%)were male,and 2143(34.1%)had a history of diabetes mellitus,with a mean(SD)age of 64.13(10.32)years.The median follow-up duration was 3.21 years.Compared with the patients with HbA1c<7%,the risk of major bleeding events during follow-up was higher in patients with HbA1c≥7%(adjusted hazard ratio[HR]=1.57;95%con-fidence interval[CI]:1.01-2.44;P=0.044),while the risk of all-cause death during follow-up was not associated with the higher HbA1c levels(adjusted HR=0.88;95%CI:0.66-1.18;P=0.398).CONCLUSIONS Compared with the lower baseline HbA1c levels,the higher baseline HbA1c levels were associated with an increase in long-term bleeding risk in NSTE-ACS patients undergoing PCI,though higher baseline HbA1c levels were not associ-ated with the higher risk in all-cause death.展开更多
According to the data in the past nine years in Heyuan urban district and its adjacent five counties,annual,seasonal and monthly change characteristics of heat island effect in Heyuan City and its meteorological influ...According to the data in the past nine years in Heyuan urban district and its adjacent five counties,annual,seasonal and monthly change characteristics of heat island effect in Heyuan City and its meteorological influence factors were analyzed. The results showed that the intensity of heat island effect in central urban district and suburb of Heyuan City overall showed an upward trend from 2007 to 2015. From 2007 to 2012,heat island effect showed a slow weakening trend; from 2012 to 2013,heat island effect significantly enhanced and then weakened; after 2013,heat island effect significantly reduced. Heat island effect of Heyuan was the strongest in winter,followed by autumn,and it was the weakest in summer.The strongest heat island effect occurred in October,while the weakest occurred in July. According to the grey correlation analysis,the main factors affecting urban heat island effect of Heyuan were analyzed,and the order of each influence factor was as follows: average wind speed > relative humidity > rainfall > sunshine hours.展开更多
The pathogens of most infectious diseases invade the host through mucosal sites,and immunization with mucosal vaccines is the best means of combating these infectious diseases.Oral delivery and nasal delivery are the ...The pathogens of most infectious diseases invade the host through mucosal sites,and immunization with mucosal vaccines is the best means of combating these infectious diseases.Oral delivery and nasal delivery are the most common methods of mucosal vaccination.However,the delivery process is inefficient,and mucosal vaccination is ineffective because the vaccine formulation is easily and rapidly removed and has difficulty in crossing the mucosal surface.In this paper,we investigated whether the mucosal immune response could be enhanced by ultrasound facilitation of nasal mucosal delivery of vaccine preparations.For this purpose,we used manganese dioxide(MnO2)as the vaccine carrier/adjuvant,coated with chitosan oligosaccharide(COS)to enhance mucosal adsorption,and further physically adsorbed model antigen ovalbumin(OVA)to construct a nanoparticulate vaccine formulation MnO2@COS@OVA.Ultrasound treatment was found to promote antigen delivery and recruitment of dendritic cells(DCs)and macrophages as well as T-cell infiltration in nasal mucosal tissues through nasal mucosal immunization studies.With ultrasound assistance,MnO2@COS@OVA particles promoted the maturation of DCs in vitro and in vivo and promoted the production of effector memory T cells in vivo and cytokine secretion by splenocytes in vitro.In particular,ultrasound treatment significantly increased the levels of secretory IgA antibodies in the nasal mucosa and genital tract mucosa of experimental mice.In addition,the experimental data showed that the MnO2@COS@OVA particles had good biocompatibility and caused no significant damage to the nasal mucosal and vital organ tissue.These data suggest that ultrasound treatment can promote the induction of efficient immune responses to mucosal vaccines and provide new ideas for the opening and clinical translation of mucosal vaccines.展开更多
Bilayer composite materials of Cu-coated Fe and CuSn10 containing 0%,5%,10%,15%,20%,25%,30%,35%,40%,45%,50%Cu-coated Fe were prepared in mesh belt sintering furnace.Microscopic pore morphology of materials was observe...Bilayer composite materials of Cu-coated Fe and CuSn10 containing 0%,5%,10%,15%,20%,25%,30%,35%,40%,45%,50%Cu-coated Fe were prepared in mesh belt sintering furnace.Microscopic pore morphology of materials was observed,bending strength was tested.Results show that,There is a good bonding between Cu-coated Fe and CuSn10,with the increase of Cu-coated Fe content from 0%to 50%,bending strength of bilayer composite materials increases.展开更多
With the tightening of house purchase policies in recent years, the introduction of financial and land restriction policies, as well as the impact of the COVID-19 pandemic, real estate bombshells are common. Real esta...With the tightening of house purchase policies in recent years, the introduction of financial and land restriction policies, as well as the impact of the COVID-19 pandemic, real estate bombshells are common. Real estate is in the critical stage of transformation and upgrading, and industrial development is facing dire challenges and pressure for survival. As an important part of enterprise management, financial management is directly related to the success or failure of enterprise development. Facing the financial risks emerging in the financial management of the real estate industry at this stage, this review begins from financial management personnel training, investment calculation management, budget management, and asset management in the effort of optimizing the real estate financial management operating mechanism under the new situation and ensuring the healthy and stable development of real estate enterprises, while maintaining core competitiveness.展开更多
Exploring the therapeutic effect of single atom catalysts beyond reactive oxygen species(ROS)modulation would boost the prosperity of nanomedicine in cancer treatment.Autophagy as a vital therapy target offers new opt...Exploring the therapeutic effect of single atom catalysts beyond reactive oxygen species(ROS)modulation would boost the prosperity of nanomedicine in cancer treatment.Autophagy as a vital therapy target offers new options for the control of renal cell carcinoma(RCC)progression.Herein,Fe single atom-decorated graphene oxide(Fe_(1)-GO)nanosheet is developed to be a feasible autophagy inducer in RCC treatment.With the well-dispersed O-Fe_(1)-O active sites,Fe_(1)-GO kills ACHN cells effectively but maintains acceptable cytotoxicity to the normal podocyte and HK2 ones.In-depth analyses ascribe the inhibition of ACHN cells to the upregulated autophagy instead of the commonly known catalytic ROS generation.The in vivo therapeutic effect of Fe_(1)-GO nanomedicine is also validated by the RCC-bearing BALB/c mice model,realizing an 89% reduction of tumor weight and good biosafety.This work provides new insights into the design of autophagy regulators as well as potential therapeutic strategies for RCC treatment.展开更多
Background:The relationship between the regression and prognosis of melanoma has been debated for years.When competing-risk events are present,using traditional survival analysis methods may induce bias in the identif...Background:The relationship between the regression and prognosis of melanoma has been debated for years.When competing-risk events are present,using traditional survival analysis methods may induce bias in the identified prognostic factors that affect patients with regressive melanoma.Methods:Data on patients diagnosed with regressive melanoma were extracted from the Surveillance,Epidemiology,and End Results(SEER)database during 2000-2019.Cumulative incidence function and Gray's test were used for the univariate analysis,and the Cox proportional-hazards model and the Fine-Gray model were used for the multivariate analysis.Results:A total of 1442 eligible patients were diagnosed with regressive melanoma,including 529 patients who died:109 from regressive melanoma and 420 from other causes.The multivariate analysis using the Fine-Gray model revealed that SEER stage,surgery status,and marital status were important factors that affected the prognosis of regressive melanoma.Due to the existence of competing-risk events,the Cox model may have induced biases in estimating the effect values,and the competing-risks model was more advantageous in the analysis of multipleendpoint clinical survival data.Conclusion:The findings of this study may help clinicians to better understand regressive melanoma and provide reference data for clinical decisions.展开更多
Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few...Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few are available for mice. Our aim is to develop a thoracic progressive compression mice model of spinal cord injury. In this study, adult wild-type C57BL/6 mice were divided into two groups: in the surgery group, a screw was inserted at T9 lamina to compress the spinal cord, and the compression was increased by turning it further into the canal(0.2 mm) post-surgery every 2 weeks up to 8 weeks. In the control group, a hole was drilled into the lamina without inserting a screw. The results showed that Basso Mouse Scale scores were lower and gait worsened. In addition, the degree of hindlimb dysfunction in mice was consistent with the degree of spinal cord compression. The number of motor neurons in the anterior horn of the spinal cord was reduced in all groups of mice, whereas astrocytes and microglia were gradually activated and proliferated. In conclusion, this progressive compression of thoracic spinal cord injury in mice is a preferable model for chronic progressive spinal cord compression injury.展开更多
The high-energy lithium/sulfur(Li/S) battery has become a very popular topic of research in recent years due to its high theoretical capacity of 1672 m Ah/g. However, the polysulfide shuttle effect remains of great co...The high-energy lithium/sulfur(Li/S) battery has become a very popular topic of research in recent years due to its high theoretical capacity of 1672 m Ah/g. However, the polysulfide shuttle effect remains of great concern with a great number of publications dedicated to its mitigation. In this contribution, a three-dimensional(3D) reduced graphene oxide/activated carbon(RGO/AC) film, synthesized by a simple hydrothermal method and convenient mechanical pressing, is sandwiched between the separator and the sulfur-based cathode, acting as a functional interlayer to capture and trap polysulfide species. Consequently, the Li/S cell with this interlayer shows an impressive initial discharge capacity of 1078 m Ah/g and a reversible capacity of 655 m Ah/g even after 100 cycles. The RGO/AC interlayer impedes the movement of polysulfide while providing unimpeded channels for lithium ion mass transfer. Therefore, the RGO/AC interlayer with a well-designed structure represents strong potential for high-performance Li/S batteries.展开更多
Bisphenol A(BPA),one of the most commonly used plastic organic monomers,is widely used in manufacturing food packaging and containers.However,the gradual emissions of BPA from manufacturing plastic products bring grea...Bisphenol A(BPA),one of the most commonly used plastic organic monomers,is widely used in manufacturing food packaging and containers.However,the gradual emissions of BPA from manufacturing plastic products bring great potential in human health threats,which urgently need to develop a simple and rapid method for detecting BPA.Cetyltrimethylammonium bromide(CTAB),a typical surfactant,is used to enhance the electrochemical detection of trace endocrine disruptors due to the fact that it can effectively enrich and absorb hydrophobic phenolic compounds through the hydrophobicity of its long-chain alkanes.Based on these,the present study reports a ternary composite of Au on zinc oxide/reduced graphene oxide nanosheets(Au/ZnO/rGO)as electrochemical sensor for detecting BP A.With the addition of CTAB,the analytic performances toward BP A detection are significantly improved 3.8 times compared with those without CTAB.The pH,accumulation potential and time are optimized.Moreover,the electrochemical activity of CTAB/Au/ZnO/rGO sensor is also evaluated by cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS),differential pulse voltammetry(DPV)and scan rate.The sensor displays two linear range from 10to 1340 nmol·L^(-1)and 1340 to 10,000 nmol·L^(-1),and a low detection limit of 4.95 nmol·L^(-1).Lastly,the sensor also exhibits good reproducibility,selectivity and potential practical application for BPA detection in real samples.展开更多
Since 1998, the author of this article has treated 35 cases of insomnia with body acupuncture plus the plum-blossom needle tapping, and obtained satisfactory results as reported in the following.
A new algorithm named kernel bisecting k-means and sample removal(KBK-SR) is proposed as sampling preprocessing for support vector machine(SVM) training to improve the efficiency.The proposed algorithm tends to quickl...A new algorithm named kernel bisecting k-means and sample removal(KBK-SR) is proposed as sampling preprocessing for support vector machine(SVM) training to improve the efficiency.The proposed algorithm tends to quickly produce balanced clusters of similar sizes in the kernel feature space,which makes it efficient and effective for reducing training samples.Theoretical analysis and experimental results on three UCI real data benchmarks both show that,with very short sampling time,the proposed algorithm dramatically accelerates SVM sampling and training while maintaining high test accuracy.展开更多
The present situation of English writing in junior high schools includes the following aspects:first,students are weak in English writing because they lack vocabulary and do not use vocabulary appropriately;second,the...The present situation of English writing in junior high schools includes the following aspects:first,students are weak in English writing because they lack vocabulary and do not use vocabulary appropriately;second,they often make grammar errors in writing;as a result,they do not obtain high scores in English writing;third,they form sentences based on their habit of thinking in their mother-tongue because of the influence of mother tongue transfer;in that case,Chinglish often appears in their compositions,and this is one of the main reasons they do not obtain high scores in English writing;finally,they do not arrange their compositions well,so most of their compositions are loosely organized.As reading and writing are designed as two separated parts in most English textbooks used in China,it is a challenge for teachers to design post-reading activities to integrate reading and writing because it is time-consuming.Based on the present situation of students’English writing and the teaching situation of English writing in junior high schools,this paper will discuss how to utilize post-reading activities to help students memorize vocabulary effectively,use vocabulary and grammar appropriately,avoid the influence of mother-tongue transfer,and build compact structures,so that they can improve their English writing skills.This discussion is based on the awareness of integrating reading with writing and making reading a supportive element of writing by utilizing post-reading activities.展开更多
The increasing use of renewable energy in the power system results in strong stochastic disturbances and degrades the control performance of the distributed power grids.In this paper,a novel multi-agent collaborative ...The increasing use of renewable energy in the power system results in strong stochastic disturbances and degrades the control performance of the distributed power grids.In this paper,a novel multi-agent collaborative reinforcement learning algorithm is proposed with automatic optimization,namely,Dyna-DQL,to quickly achieve an optimal coordination solution for the multi-area distributed power grids.The proposed Dyna framework is combined with double Q-learning to collect and store the environmental samples.This can iteratively update the agents through buffer replay and real-time data.Thus the environmental data can be fully used to enhance the learning speed of the agents.This mitigates the negative impact of heavy stochastic disturbances caused by the integration of renewable energy on the control performance.Simulations are conducted on two different models to validate the effectiveness of the proposed algorithm.The results demonstrate that the proposed Dyna-DQL algorithm exhibits superior stability and robustness compared to other reinforcement learning algorithms.展开更多
基金The 2023 Guangdong Provincial Education Department Scientific Research Cultivation Project“Research on the Role of Informatization in Promoting the Professional Development of Teachers in Northeast Guangdong Province”(Project number:2023-SKPY01)。
文摘With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,these technologies remain detached from rural teachers,failing to significantly enhance the quality of education and teaching in rural areas.Rural education is a crucial aspect of ensuring balanced development in education.The question of how to enhance rural teachers’technological application abilities and fully leverage the positive role of technology in rural education and teaching has become a significant topic of current research on rural education issues.To better address this question,this study conducted a thorough examination of the specific appeals of rural teachers in the process of technology enablement.It was discovered that rural teachers generally face dilemmas such as insufficient technological application abilities,difficulties in obtaining quality teaching resources,and the lack of continuous technical support and update mechanisms.Based on these findings,specific pathways such as strengthening rural teacher training,optimizing the allocation of educational resources,and establishing mechanisms for continuous technical support and updates are proposed to aid in the high-quality development of rural education.
文摘The red beds of the northern Heyuan Basin (Guangdong Province, China) are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian Formation, and Zhenshui Formation of the Nanxiong Group, Shanghu Formation and Danxia Formation. The Nanxiong Group with relatively mature coarse clastic rocks attains about 2940 m in thickness. The Dafeng Formation is 837 m thick, consisting of conglomerates and sandy conglomerates; the Zhutian Formation, which is 1.200 m thick, consists of purplish red sandstone with gravels, poorly sorted sandstone, feldspathic quartzose sandstone banded granular conglomerate, siltstone, and sandy mudstone. The Zhutian Formation is rich in calcareous concretions. Heyuannia (Oviraptoridae) and turtle fossils were found in this formation. The Zhenshui Formation deposited to a thickness of 900 m consists of coarse sediments, including granular conglomerate, and gravelly sandstone with well developed cross-beddings; the Shanghu Formation, which is 820 m thick, consists of purplish red granular conglomerate coarse sandstone intercalated with fine si^tstone; the Danxia Formation characterized by the Danxia ~andform is composed of coarse c^astic gravels and sandy gravels. The lower part of the Nanxiong Group whence dinosaur eggs and derived oviraptorosaurs come, belongs to the Late Cretaceous. No fossils are found in the Shanghu Formation or the Danxia Formation, but their stratigraphic order of superposition on the Nanxiong Group clearly shows their younger age.
基金supported by agrant from the National Natural Science Foundation of China (40872017)
文摘The Zhutian and Dafeng formations (Upper Cretaceous) of the Heyuan Basin in northeastern Guangdong Province, China, have produced thousands of dinosaur eggs. Macromorphological features (egg diameter, egg shape, outer surface texture, and shell thickness) of 461 eggs were analyzed using non-destructive techniques and subjected to statistical analyses in order to assess their diversity and taxonomic affinities. Three types (1, 2 and 3) of eggs were discerned based on shape and outer surface morphology. Type 1 eggs are spherical to ellipsoidal in shape and have a rough surface. Three subtypes (Type 1-A-l, l-A-2, and l-B) are apparent from scatter plots and cluster analyses of egg diameters and shell thickness. Type 2 eggs are elongate with linear ornamentation on the surface, and are comparable to eggs that belong to the oofamily Elongatoolithidae. Type 3 eggs are elongate with a smooth surface, and are assigned to the oofamily Prismatoolithidae. Macromorphological features of the various egg types suggest that Type 1 could have been laid by ornithischian, sauropod or therizinosaur dinosaurs, Type 2 by oviraptorids, and Type 3 by troodontids. This study represents the first comprehensive statistical analysis of macrofeatures of dinosaur eggs, and reveals taxonomic diversity in the dinosaurs that were laying eggs in the Upper Cretaceous Heyuan area heretofore unrecognized in skeletal remains.
基金Supported by the National Natural Science Foundation of China(Nos.31670969,82172440)the Fundamental Research Funds for the Central Universities(Nos.21620417,21621103)+2 种基金the Medical Joint Fund of Jinan University(No.YXJC2022005)the National Key Research and Development Program of China(No.2022YFE0206200)the Funding of Science and Technology Projects in Guangzhou(Nos.202206010158,202201020087)。
文摘A composite bone cement based onα-TCP with self-reinforcing characteristics is prepared by compounding cellulose whiskers and polyvinyl alcohol in different proportions.In this system,we are inspired by the sea cucumber,which can alter the stiffness of their inner dermis reversibly.Through the formation of hydrogen bonds between the hydroxyl groups on the cellulose whiskers and PVA,the bone cement matrix can be strengthened during the curing process of cement.In the process of bone cement blending,there is more water,the hydrogen bond connection is destroyed,so the slurry has better fluidity at this time.As the hydration of the bone cement progresses,the reduction of the water phase leads to the formation of a permeable network structure of hydrogen bond connections between the whiskers.The dual-phase action of PVA and whiskers greatly increases the mechanical strength of the bone cement system(5.5 to 23.8 MPa),while the presence of polyvinyl alcohol improves the toughness of the bone cement system.This work was supposed to explore whether the chemoresponsive materials can be adapted to biomedical materials,for example,bone repair.
基金the Key Research and Development Program of Yunnan Province(No.202202AE090023)Key Research and Development Program of Guangdong Province(No.2022B0202040002+8 种基金2022B0202050001)the Key Laboratory of Green Processing and Intelligent Manufacturing of Lingnan Specialty Food,Ministry of Agriculturethe Heyuan Branch,Guangdong Laboratory for Lingnan Modern Agriculture Project(No.DT20220026)Talent Introduction Program of Guangdong Academy of Agricultural Sciences(No.R2022YJ-YB3004)the Basic and Applied Basic Research Project of Guangdong Province(No.2022A15151102272023A1515012386)the Science and Technology Planning Project of Guangzhou(No.2023A04J0828)the Guangdong Provincial Special Fund for Modern Agriculture Industry Technology Innovation Teams(No.202109TD)the Special Fund Project for Teachers’Scientific and Technological Achievements Transformation in Shunde Innovation Park,National University Science Park,South China University of Technology(No.KJYS2021KZ05)for their financial support。
文摘Two oligosaccharide fractions(MLO 2-1 and 2-2)were purified from enzymatic hydrolysate of mulberry leaf polysaccharide.The results of simulated digestion showed that MLO 2-2 was a digestible oligosaccharide,which could be degraded by human digestive juice;while MLO 2-1 possessed the non-digestible property in the upper gastrointestinal tract and performed the function by regulating the gut microbiota.Hence,MLO 2-1 was selected for the further analysis.The structure of MLO 2-1 was elucidated as follow:α-T-Glcp-(1→3)-β-Glcp-(1→5)-α-Araf-(1→5)-α-Araf-1→5)-α-Araf-(1→3)-α-(2-OAc)-Glcp-1.The in vitro fecal fermentation results showed that MLO 2-1 could modulate the composition of gut microbiota.Meanwhile,MLO 2-1 was effectively metabolized by fecal bacteria to produce lactate and short chain fatty acids,especially acetate and butyrate.The specific metabolic pathways of MLO 2-1 by gut microbiota were further illuminated.Gut microbiota analysis revealed that MLO 2-1 selectively promoted the growth of Ligilactobacillus murinus,a commensal bacterium presented a reduced level in T2DM mice.Animal experiments indicated that MLO 2-1 and L.murinus exhibited hypoglycemic activities.These results demonstrated that MLO 2-1 might alleviate T2DM by selectively accelerating the proliferation of L.murinus.
基金supported by the National Key Research and Development Program of China(grant No.2016YFC0600205)the Geological Survey program of China Geological Survey(grant No.DD20160134,DD20160033)
文摘Objective Most scholars agreed that the tectonic setting of South China block(SBC)changed from Tethys during the Indosinian to Pacific tectonic regime in the Yanshanian.However,the specific change time for the transition is still in debate and the Triassic to Jurassic magmatic activity will provide a clue to better understanding the transition.
基金supported by Outstanding Young Medical Talents in Guangdong Province (KJ0120-19456)the Outstanding Young Talent Program of Guangdong Provincial People’s Hospital (Grant No.KJ012019084 and KJ012019095)+2 种基金the High-level Hospital Construction Project (Grant No. DFJH20200-21)Guangdong Provincial People’s Hospital Clinical Research Fund (Y012018085)National Natural Science Foundation of Guangdong Province (KC-022021005)
文摘OBJECTIVE To investigate the association between baseline hemoglobin A1c(HbA1c)levels and bleeding in patients with non-ST-segment elevation acute coronary syndrome(NSTE-ACS)who underwent percutaneous coronary intervention(PCI).METHODS This observational cohort study enrolled 6283 consecutive NSTE-ACS patients undergoing PCI from January 1,2010 to December 31,2014.Based on baseline HbA1c levels,the patients were divided into the group with HbA1c<7%(n=4740)and the group with HbA1c≥7%(n=1543).The primary outcomes are major bleeding(BARC grades 3-5)and all-cause death during follow-up.RESULTS Of patients enrolled,4705(74.9%)were male,and 2143(34.1%)had a history of diabetes mellitus,with a mean(SD)age of 64.13(10.32)years.The median follow-up duration was 3.21 years.Compared with the patients with HbA1c<7%,the risk of major bleeding events during follow-up was higher in patients with HbA1c≥7%(adjusted hazard ratio[HR]=1.57;95%con-fidence interval[CI]:1.01-2.44;P=0.044),while the risk of all-cause death during follow-up was not associated with the higher HbA1c levels(adjusted HR=0.88;95%CI:0.66-1.18;P=0.398).CONCLUSIONS Compared with the lower baseline HbA1c levels,the higher baseline HbA1c levels were associated with an increase in long-term bleeding risk in NSTE-ACS patients undergoing PCI,though higher baseline HbA1c levels were not associ-ated with the higher risk in all-cause death.
文摘According to the data in the past nine years in Heyuan urban district and its adjacent five counties,annual,seasonal and monthly change characteristics of heat island effect in Heyuan City and its meteorological influence factors were analyzed. The results showed that the intensity of heat island effect in central urban district and suburb of Heyuan City overall showed an upward trend from 2007 to 2015. From 2007 to 2012,heat island effect showed a slow weakening trend; from 2012 to 2013,heat island effect significantly enhanced and then weakened; after 2013,heat island effect significantly reduced. Heat island effect of Heyuan was the strongest in winter,followed by autumn,and it was the weakest in summer.The strongest heat island effect occurred in October,while the weakest occurred in July. According to the grey correlation analysis,the main factors affecting urban heat island effect of Heyuan were analyzed,and the order of each influence factor was as follows: average wind speed > relative humidity > rainfall > sunshine hours.
基金supported by the National Key R&D Program of China(No.2018YFC0311103).
文摘The pathogens of most infectious diseases invade the host through mucosal sites,and immunization with mucosal vaccines is the best means of combating these infectious diseases.Oral delivery and nasal delivery are the most common methods of mucosal vaccination.However,the delivery process is inefficient,and mucosal vaccination is ineffective because the vaccine formulation is easily and rapidly removed and has difficulty in crossing the mucosal surface.In this paper,we investigated whether the mucosal immune response could be enhanced by ultrasound facilitation of nasal mucosal delivery of vaccine preparations.For this purpose,we used manganese dioxide(MnO2)as the vaccine carrier/adjuvant,coated with chitosan oligosaccharide(COS)to enhance mucosal adsorption,and further physically adsorbed model antigen ovalbumin(OVA)to construct a nanoparticulate vaccine formulation MnO2@COS@OVA.Ultrasound treatment was found to promote antigen delivery and recruitment of dendritic cells(DCs)and macrophages as well as T-cell infiltration in nasal mucosal tissues through nasal mucosal immunization studies.With ultrasound assistance,MnO2@COS@OVA particles promoted the maturation of DCs in vitro and in vivo and promoted the production of effector memory T cells in vivo and cytokine secretion by splenocytes in vitro.In particular,ultrasound treatment significantly increased the levels of secretory IgA antibodies in the nasal mucosa and genital tract mucosa of experimental mice.In addition,the experimental data showed that the MnO2@COS@OVA particles had good biocompatibility and caused no significant damage to the nasal mucosal and vital organ tissue.These data suggest that ultrasound treatment can promote the induction of efficient immune responses to mucosal vaccines and provide new ideas for the opening and clinical translation of mucosal vaccines.
基金Research project of Heyuan polytechnic(2022ky05,2022ky06)2019 Provincial Science and Technology Special Fund("Big project"+"Task List")project(2019005,2019004).
文摘Bilayer composite materials of Cu-coated Fe and CuSn10 containing 0%,5%,10%,15%,20%,25%,30%,35%,40%,45%,50%Cu-coated Fe were prepared in mesh belt sintering furnace.Microscopic pore morphology of materials was observed,bending strength was tested.Results show that,There is a good bonding between Cu-coated Fe and CuSn10,with the increase of Cu-coated Fe content from 0%to 50%,bending strength of bilayer composite materials increases.
文摘With the tightening of house purchase policies in recent years, the introduction of financial and land restriction policies, as well as the impact of the COVID-19 pandemic, real estate bombshells are common. Real estate is in the critical stage of transformation and upgrading, and industrial development is facing dire challenges and pressure for survival. As an important part of enterprise management, financial management is directly related to the success or failure of enterprise development. Facing the financial risks emerging in the financial management of the real estate industry at this stage, this review begins from financial management personnel training, investment calculation management, budget management, and asset management in the effort of optimizing the real estate financial management operating mechanism under the new situation and ensuring the healthy and stable development of real estate enterprises, while maintaining core competitiveness.
基金supported by the National Natural Science Foundation of China(Nos.52202240,82270756 and 82000686)the China Postdoctoral Science Foundation(No.2021M701409)+3 种基金the Natural Science Foundation of Guangdong,China(No.2018A030313527)the Basic and Applied Basic Research Foundation of Guangdong Province,China(No.2019A1515010176)the Science and Technology Project of Guangzhou,China(No.202102010133)the Science and Technology Project of Shenzhen,China(No.JCYJ20190808095615389)。
文摘Exploring the therapeutic effect of single atom catalysts beyond reactive oxygen species(ROS)modulation would boost the prosperity of nanomedicine in cancer treatment.Autophagy as a vital therapy target offers new options for the control of renal cell carcinoma(RCC)progression.Herein,Fe single atom-decorated graphene oxide(Fe_(1)-GO)nanosheet is developed to be a feasible autophagy inducer in RCC treatment.With the well-dispersed O-Fe_(1)-O active sites,Fe_(1)-GO kills ACHN cells effectively but maintains acceptable cytotoxicity to the normal podocyte and HK2 ones.In-depth analyses ascribe the inhibition of ACHN cells to the upregulated autophagy instead of the commonly known catalytic ROS generation.The in vivo therapeutic effect of Fe_(1)-GO nanomedicine is also validated by the RCC-bearing BALB/c mice model,realizing an 89% reduction of tumor weight and good biosafety.This work provides new insights into the design of autophagy regulators as well as potential therapeutic strategies for RCC treatment.
基金Key Scientific Problems and Medical Technical Problems Research Project of China Medical Education Association(2022KTZ009)Guangdong Provincial Key Laboratory of Traditional Chinese Medicine Informatization(2021B1212040007).
文摘Background:The relationship between the regression and prognosis of melanoma has been debated for years.When competing-risk events are present,using traditional survival analysis methods may induce bias in the identified prognostic factors that affect patients with regressive melanoma.Methods:Data on patients diagnosed with regressive melanoma were extracted from the Surveillance,Epidemiology,and End Results(SEER)database during 2000-2019.Cumulative incidence function and Gray's test were used for the univariate analysis,and the Cox proportional-hazards model and the Fine-Gray model were used for the multivariate analysis.Results:A total of 1442 eligible patients were diagnosed with regressive melanoma,including 529 patients who died:109 from regressive melanoma and 420 from other causes.The multivariate analysis using the Fine-Gray model revealed that SEER stage,surgery status,and marital status were important factors that affected the prognosis of regressive melanoma.Due to the existence of competing-risk events,the Cox model may have induced biases in estimating the effect values,and the competing-risks model was more advantageous in the analysis of multipleendpoint clinical survival data.Conclusion:The findings of this study may help clinicians to better understand regressive melanoma and provide reference data for clinical decisions.
基金supported by the National Natural Science Foundation of China,No.31400824a grant from the Science and Technology Program of Jiangmen City of China,No.2015751the Scientific Research and Cultivating Foundation of the First Clinical Medical College of Jinan University of China,No.2013208
文摘Non-traumatic injury accounts for approximately half of clinical spinal cord injury, including chronic spinal cord compression. However, previous rodent spinal cord compression models are mainly designed for rats, few are available for mice. Our aim is to develop a thoracic progressive compression mice model of spinal cord injury. In this study, adult wild-type C57BL/6 mice were divided into two groups: in the surgery group, a screw was inserted at T9 lamina to compress the spinal cord, and the compression was increased by turning it further into the canal(0.2 mm) post-surgery every 2 weeks up to 8 weeks. In the control group, a hole was drilled into the lamina without inserting a screw. The results showed that Basso Mouse Scale scores were lower and gait worsened. In addition, the degree of hindlimb dysfunction in mice was consistent with the degree of spinal cord compression. The number of motor neurons in the anterior horn of the spinal cord was reduced in all groups of mice, whereas astrocytes and microglia were gradually activated and proliferated. In conclusion, this progressive compression of thoracic spinal cord injury in mice is a preferable model for chronic progressive spinal cord compression injury.
基金financial support from the National Natural Science Foundation of China(grant no.21406052the Program for the Outstanding Young Talents of Hebei Province(grant no.BJ2014010)the Scientific Research Foundation for Selected Overseas Chinese Scholars,Ministry of Human Resources and Social Security of China(grant no.CG2015003002)
文摘The high-energy lithium/sulfur(Li/S) battery has become a very popular topic of research in recent years due to its high theoretical capacity of 1672 m Ah/g. However, the polysulfide shuttle effect remains of great concern with a great number of publications dedicated to its mitigation. In this contribution, a three-dimensional(3D) reduced graphene oxide/activated carbon(RGO/AC) film, synthesized by a simple hydrothermal method and convenient mechanical pressing, is sandwiched between the separator and the sulfur-based cathode, acting as a functional interlayer to capture and trap polysulfide species. Consequently, the Li/S cell with this interlayer shows an impressive initial discharge capacity of 1078 m Ah/g and a reversible capacity of 655 m Ah/g even after 100 cycles. The RGO/AC interlayer impedes the movement of polysulfide while providing unimpeded channels for lithium ion mass transfer. Therefore, the RGO/AC interlayer with a well-designed structure represents strong potential for high-performance Li/S batteries.
基金financially supported by the Fundamental Research Funds for the Central UniversitiesGuangdong Basic and Applied Basic Research Foundation(No.2020B1515020038)Funding by Science and Technology Projects in Guangzhou(No.202201020083)。
文摘Bisphenol A(BPA),one of the most commonly used plastic organic monomers,is widely used in manufacturing food packaging and containers.However,the gradual emissions of BPA from manufacturing plastic products bring great potential in human health threats,which urgently need to develop a simple and rapid method for detecting BPA.Cetyltrimethylammonium bromide(CTAB),a typical surfactant,is used to enhance the electrochemical detection of trace endocrine disruptors due to the fact that it can effectively enrich and absorb hydrophobic phenolic compounds through the hydrophobicity of its long-chain alkanes.Based on these,the present study reports a ternary composite of Au on zinc oxide/reduced graphene oxide nanosheets(Au/ZnO/rGO)as electrochemical sensor for detecting BP A.With the addition of CTAB,the analytic performances toward BP A detection are significantly improved 3.8 times compared with those without CTAB.The pH,accumulation potential and time are optimized.Moreover,the electrochemical activity of CTAB/Au/ZnO/rGO sensor is also evaluated by cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS),differential pulse voltammetry(DPV)and scan rate.The sensor displays two linear range from 10to 1340 nmol·L^(-1)and 1340 to 10,000 nmol·L^(-1),and a low detection limit of 4.95 nmol·L^(-1).Lastly,the sensor also exhibits good reproducibility,selectivity and potential practical application for BPA detection in real samples.
文摘Since 1998, the author of this article has treated 35 cases of insomnia with body acupuncture plus the plum-blossom needle tapping, and obtained satisfactory results as reported in the following.
基金National Natural Science Foundation of China (No. 60975083)Key Grant Project,Ministry of Education,China(No. 104145)
文摘A new algorithm named kernel bisecting k-means and sample removal(KBK-SR) is proposed as sampling preprocessing for support vector machine(SVM) training to improve the efficiency.The proposed algorithm tends to quickly produce balanced clusters of similar sizes in the kernel feature space,which makes it efficient and effective for reducing training samples.Theoretical analysis and experimental results on three UCI real data benchmarks both show that,with very short sampling time,the proposed algorithm dramatically accelerates SVM sampling and training while maintaining high test accuracy.
文摘The present situation of English writing in junior high schools includes the following aspects:first,students are weak in English writing because they lack vocabulary and do not use vocabulary appropriately;second,they often make grammar errors in writing;as a result,they do not obtain high scores in English writing;third,they form sentences based on their habit of thinking in their mother-tongue because of the influence of mother tongue transfer;in that case,Chinglish often appears in their compositions,and this is one of the main reasons they do not obtain high scores in English writing;finally,they do not arrange their compositions well,so most of their compositions are loosely organized.As reading and writing are designed as two separated parts in most English textbooks used in China,it is a challenge for teachers to design post-reading activities to integrate reading and writing because it is time-consuming.Based on the present situation of students’English writing and the teaching situation of English writing in junior high schools,this paper will discuss how to utilize post-reading activities to help students memorize vocabulary effectively,use vocabulary and grammar appropriately,avoid the influence of mother-tongue transfer,and build compact structures,so that they can improve their English writing skills.This discussion is based on the awareness of integrating reading with writing and making reading a supportive element of writing by utilizing post-reading activities.
基金supported by the National Natural Sci-ence Foundation of China(No.52277108)Guangdong Provincial Department of Science and Technology(No.2022A0505020015).
文摘The increasing use of renewable energy in the power system results in strong stochastic disturbances and degrades the control performance of the distributed power grids.In this paper,a novel multi-agent collaborative reinforcement learning algorithm is proposed with automatic optimization,namely,Dyna-DQL,to quickly achieve an optimal coordination solution for the multi-area distributed power grids.The proposed Dyna framework is combined with double Q-learning to collect and store the environmental samples.This can iteratively update the agents through buffer replay and real-time data.Thus the environmental data can be fully used to enhance the learning speed of the agents.This mitigates the negative impact of heavy stochastic disturbances caused by the integration of renewable energy on the control performance.Simulations are conducted on two different models to validate the effectiveness of the proposed algorithm.The results demonstrate that the proposed Dyna-DQL algorithm exhibits superior stability and robustness compared to other reinforcement learning algorithms.