Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development...Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development of microwave absorbers(MAs).In this paper,a facile and propagable Ni-nitrilotriacetic acid chelate(NAC)derived strategy was proposed to selectively fabricate zero-dimensional(0D)/one-dimensional(1D)porous Ni/C magnetic heterostructured nanorods(MHNRs)consisting of 1D carbon nanorod,lots of pores and 0D Ni nanoparticles via a combined hydrothermal and thermally treated methods.The porous Ni/C MHNRs displayed the progressively improved Ni and C crystallinity by controlling the temperature,which resulted in the tunable electromagnetic and microwave absorption properties(MAPs).Additionally,0D/1D porous CoNi/C and Co/C MHNRs could be selectively produced through this strategy by adopting CoNi-NAC and Co-NAC as precursors.Benefiting from desirable interface and magnetic/dielectric synergies,the acquired 0D/1D porous Ni/C,CoNi/C and Co/C MHNRs presented excellent MAPs and certain corrosion resistance properties.In especial,Co/C MHNRs displayed a strong absorption capacity(−47.89 dB),an ultrawide effective absorption bandwidth(8.40 GHz)and small matching thicknesses(∼2 mm),which were a desirable candidate for MAs.Consequently,a facile,low-cost and propagable metal-NAC derived strategy was proposed to synthesize 0D/1D porous carbon-based MHNRs,which presented an alternative technique to develop lightweight efficient MAs.展开更多
Exploring electrode materials with larger capacity,higher power density and longer cycle life was critical for developing advanced flexible lithium-ion batteries(LIBs).Herein,we used a controlled two-step method inclu...Exploring electrode materials with larger capacity,higher power density and longer cycle life was critical for developing advanced flexible lithium-ion batteries(LIBs).Herein,we used a controlled two-step method including electrospraying followed with calcination treatment by CVD furnace to design novel electrodes of Si/Si_(x)/C and Sn/C microrods array consisting of nanospheres on flexible carbon cloth substrate(denoted as Si/Si_(x)/C@CC,Sn/C@CC).Microrods composed of cumulated nanospheres(the diameter was approximately 120 nm)had a mean diameter of approximately 1.5μm and a length of around 4.0μm,distributing uniformly along the entire woven carbon fibers.Both of Si/Si/Si_(x)/C@CC and Sn/C@CC products were synthesized as binder-free anodes for Li-ion battery with the features of high reversible capacity and excellent cycling.Especially Si/Six/C electrode exhibited high specific capacity of about 1750 mA∙h∙g^(−1)at 0.5 A∙g^(−1)and excellent cycling ability even after 1050 cycles with a capacity of 1388 mA∙h∙g^(−1).Highly flexible Si/Si_(x)/C@CC//LiCoO_(2)batteries based on liquid and solid electrolytes were also fabricated,exhibiting high flexibility,excellent electrical stability and potential applications in flexible wearable electronics.展开更多
Hepatitis C virus(HCV)infection has been increasingly associated with cardio-vascular complications,particularly atherosclerosis and cardiomyopathy,in addition to its primary hepatic effects.Studies indicate a higher ...Hepatitis C virus(HCV)infection has been increasingly associated with cardio-vascular complications,particularly atherosclerosis and cardiomyopathy,in addition to its primary hepatic effects.Studies indicate a higher prevalence of carotid atherosclerosis in patients with chronic hepatitis C infection,with viral load and steatosis emerging as independent risk factors.HCV-related athero-sclerosis appears to develop through complex processes involving endothelial dysfunction,inflammation,oxidative stress,and immune dysregulation.Key cytokines,including tumor necrosis factor-alpha and interleukin-6,increase inflammatory responses,while oxidative stress markers,such as malondial-dehyde,are associated with an increased risk of atherogenesis.In addition,HCV infection has been linked to cardiomyopathy.Direct viral effects,including HCV replication within cardiomyocytes and cytotoxicity induced by viral proteins,lead to myocardial injury and functional decline.Indirectly,HCV triggers immune-mediated damage,with heightened pro-inflammatory cytokines exacerbating cardiomyocyte apoptosis and fibrosis.Furthermore,HCV infection promotes a procoagulant imbalance,as evidenced by elevated factor VIII levels and thrombin potential,contributing to the increased cardiovascular risk.While substantial evidence indicates a relationship between HCV and cardiovascular disease,further research is needed to establish causality and guide therapeutic interventions.展开更多
Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is...Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.展开更多
The use of conventional herbal medicines is a rapidly expanding phenomenon in developed nations. For instance, 30%–50% of all drug use in China is attributed to traditional herbal preparations. Current study evaluate...The use of conventional herbal medicines is a rapidly expanding phenomenon in developed nations. For instance, 30%–50% of all drug use in China is attributed to traditional herbal preparations. Current study evaluated the antioxidant (DPPH, FRAP), total phenolic and flavonoid content, antibacterial activity, and DNA damage protective potential of aqueous and methanolic extracts obtained from the aerial parts and roots of Cymbocarpum wiedemannii Boiss., an endemic plant in Turkey. In antioxidant analyses, the methanolic extract of the aerial parts showed the highest %DPPH (73.38) and IC50 (3.46 mg/mL) values. The FRAP analysis revealed the highest iron-reducing capacity in the methanolic extract of the aerial parts (108.10 ± 0.11 mg FeSO4/mL). The aqueous extract of the aerial parts exhibited the highest total phenolic content (1.69 ± 0.02 mg gallic acid/mL), while the methanolic extract of the aerial parts had the highest total flavonoid content (13.53 ± 0.09 mg rutin/mL). Antibacterial activity tests showed no significant effect at a concentration of 1 mg/mL for the samples. DNA protective effects were tested on pBR322 plasmid DNA, demonstrating that both aerial and root extracts could protect DNA from Fenton reaction-induced damage. In conclusion, C. wiedemannii exhibits potential bioactive properties, particularly in terms of its antioxidant and DNA protective effects.展开更多
Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produ...Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produced by photosynthesis and exogenous N within the rice plant-soil system under straw return remains unclear.A long-term straw return pot trial experiment was conducted in a double cropping rice system,incorporating treatments of inorganic fertilizer application with straw removal(F),straw burning and ash return with reducing inorganic fertilizers(SBR),and straw return with reducing inorganic fertilizers(SR)to investigate C sequestration and exogenous N uptake using ^(13)C pulse and ^(15)N isotope tracer techniques.The SR treatment had significantly higher soil ^(13)C abundance,by 24.4 and 25.4%,respectively,^(13)C concentrations in aboveground plant parts,by 18.4 and 35.8%respectively,and ^(15)N concentrations in rice panicles,by 12.8 and 34.3%than the SBR and F treatments.This enhancement contributed to a higher total organic C concentration and increased rice grain yield in the SR treatment.Furthermore,the SR treatment had significantly higher photosynthetic C,by 9.8%,which was directly transferred to soil C.The SR treatment had a higher distribution of photosynthetic C in the leaves and stems,but a lower distribution in the panicle compared to the SBR treatment.This finding is advantageous for sequestering photosynthetic C into the soil through straw return;conversely,opposite trends were observed in ^(15)N distribution.In addition,rice plants in the SR treatment had increased N uptake from urea and soil N sources,enhancing N recovery by 9.2 and 12.5%,respectively,and reducing soil N residues.Correlation analysis showed that the SR treatment increased the concentrations of ^(13)C in leaves and roots while decreasing the ^(15)N abundance in all rice organs,thereby contributing to an increase in rice yield.The partial least square path model suggested that the increase in rice yield under the SR treatment was primarily linked to ^(13)C accumulation within the rice plant-soil system.The results suggest that straw return increases the sequestration of photosynthetic C and exogenous N in the rice plant-soil system and increases N utilization efficiency,which subsequently improves both rice and soil productivity.展开更多
The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research ...The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research investigates the impact of these substances individually and in combination on antioxidant capabilities and anti-wrinkle firming effects.The results demonstrate that the combination of Vc and black Ganoderma lucidum extract exhibits significant antioxidant abilities at various concentrations,and is more effective than when each is used separately,indicating a synergistic interaction between them.Additionally,the combination also shows significant inhibition of elastase,suggesting potential applications in delaying the aging process of the skin.Furthermore,highperformance liquid chromatography(HPLC)was used to determine if reactions occur among the components of the mixture.The findings reveal that the concentration of Vc in the mixture is very close to the theoretical concentration and relatively stable,suggesting that the components function independently.A quantitative analysis using the Bliss independence model further confirms the synergistic effects of Vc and black Ganoderma lucidum extract at specific ratios,providing a scientific basis for the development of efficacious cosmetic products.展开更多
The aim of this study was to assess the seroprevalence of viral hepatitis B and C and co-infection with HIV among volunteer blood donors at the blood sampling and distribution depot (BSDD) in Ouahigouya. Patients and ...The aim of this study was to assess the seroprevalence of viral hepatitis B and C and co-infection with HIV among volunteer blood donors at the blood sampling and distribution depot (BSDD) in Ouahigouya. Patients and methods: Our study population consisted of all volunteer blood donors who had donated during a 2-year period from 1 January 2019 to 31 December 2020. Samples were taken from patients with no contraindications and serological tests were performed using ELISA tests. HBsAg, HCV-Ac and HIV serology were tested. All samples reactive for HIV, HBV and HCV were retested for confirmation using a second enzyme-linked immunosorbent assay. A result was considered positive if both the first and second tests were positive. Results: In two years, the Ouahigouya BSDD recorded 9726 donations, including 7983 new donors and 1743 former donors. The average age of donors was 25.59 years, with a sex ratio of 3.4. The seroprevalence of HBV, HCV and HIV was 7.31%, 3.10% and 2.12% respectively. HBV-HCV co-infection was found in 0.32% of cases, HIV-HBV, HIV-HCV, and HIV-HBV-HCV co-infection were found in 0.25%, 0.09% and 0.04% respectively. Conclusion: The seroprevalence of viral hepatitis B and C remains high among volunteer blood donors in Ouahigouya, although a decline in seroprevalence appears to be on the horizon.展开更多
Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations b...Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations by formulating a double nano-emulsion(W/O/W)system incorporating macadamia oil and tea tree oil,using homogenization and phase inversion temperature(PIT)techniques.Comprehensive physicochemical charac-terization,including droplet size,polydispersity index(PDI),zeta potential,turbidity,Fourier transform infrared spectroscopy(FTIR),and SEM,was conducted alongside stability assessments under varying pH,temperature,and storage conditions.The optimized nano-emulsions exhibited nanoscale droplet sizes(10-40 nm),low PDI values(indicating high uniformity),and robust stability.Interestingly,the formulation with 2%W/O loading,with a particle size of 11.57 nm and a PDI of 0.04,demonstrated an antioxidant capacity of 4622.62μg ascorbic acid equivalents(AA)/g,which was significantly higher(p<0.05)compared to both natural oils(macadamia oil:20.91μg AA/g,tea tree oil:16.86μg AA/g)and a 10%Vitamin C aqueous solution(592.94μg AA/g).FTIR analysis confirmed the molecular integrity of Vitamin C and its successful encapsulation with macadamia and tea tree oils,while SEM images revealed uniformly spherical and well-dispersed droplets.Moreover,the formulation retained its structural integrity and antioxidant functionality under diverse pH and thermal conditions.These findings underscore the potential of double nano-emulsion systems to overcome the stability challenges of Vitamin C,offering a promising approach to enhance its bioavailability and therapeutic performance in phar-maceutical and cosmetic applications.展开更多
The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium s...The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium systems.In this work,we study the possible bound states in the triple-ηcand triple-J/ψsystems with J^(PC)=0^(-+)and 1^(--),respectively.In quantum chromodynamics sum rules,we calculate the two-point correlation functions and spectral functions up to the dimension-four gluon condensate.We use the iterative dispersion relation approach to deal with the five-loop banana integrals,which significantly improves computational efficiency.Our results show that the masses of triple-ηcand triple-J/ψstates lie below the corresponding mass thresholds,supporting the existence of such three-body bound states.展开更多
This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe ...This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe diabetic foot ulcers,carry significant risks of postoperative complications such as infection and delayed wound healing.Elevated hemoglobin A1c levels,indicative of poor glycemic control,and a history of kidney transplantation,due to required immunosuppressive therapy,are key factors influencing these outcomes.This paper emphasizes the need for enhanced glycemic management and personalized postoperative care,particularly for immunocompromised individuals,to minimize complications and improve patient prognosis.Future research should focus on prospective studies to validate targeted interventions and optimize care strategies,ultimately aiming to reduce the healthcare burden associated with diabetic foot complications.展开更多
The Hastelloy C22 coatings on Q235 steel substrate were produced by high power diode laser cladding technique. Their corrosion behaviors in static and cavitation hydrochloric, sulfuric and nitric acid solutions were i...The Hastelloy C22 coatings on Q235 steel substrate were produced by high power diode laser cladding technique. Their corrosion behaviors in static and cavitation hydrochloric, sulfuric and nitric acid solutions were investigated. The electrochemical results show that corrosion resistance of coatings in static acid solutions is higher than that in cavitation ones. In each case, coating corrosion resistance in descending order is in nitric, sulfuric and hydrochloric acid solutions. Obvious erosion-corrosion morphology and serious intercrystalline corrosion of coating are noticed in cavitation hydrochloric acid solution. This is mainly ascribed to the aggressive ions in hydrochloric acid solution and mechanical effect from cavitation bubbles collapse. While coating after corrosion test in cavitation nitric acid solution shows nearly unchanged surface morphology. The results indicate that the associated action of cavitation and property of acid solution determines the corrosion development of coating. Hastelloy C22 coating exhibits better corrosion resistance in oxidizing acid solution for the stable formation of dense oxide film on the surface.展开更多
A study was performed on the long-term effect of straw incorporation on soil microbial biomass C contents, C and N dynamics in both Rothamsted and Woburn soils. The results showed that for both soils,the microbial bio...A study was performed on the long-term effect of straw incorporation on soil microbial biomass C contents, C and N dynamics in both Rothamsted and Woburn soils. The results showed that for both soils,the microbial biomass C contents were significantly different among all the treatments, and followed the sequence in treatments of straw chopped and incorporated into 10 cm (CI10) > straw burnt and incorporated into 10 cm (BI10) > straw chopped and incorporated into 20 cm (CI20) > straw burnt and incorporated into 20 cm (BI20). Laboratory incubation of soils showed that the cumulative CO2 evolution was closely related to the soil microbial biomass C content. Carbon dioxide evolution rates (CO2-C, μg (g d) -1 ) decreased rapidly in the first two weeks’ incubation, then decreased more slowly. The initial K2SO4-extractable NH4-N and NO3-N contents were low and similar in all the treatments, and all increased gradually with the incubation time. However, net N immobilization was observed in chopped treatments for Rothamsted soils during the first 4 weeks. Nevertheless, more N mineralization occurred in neatment CI10 than any other treatment at the end of incubation for both soils. The Woburn soils could more easily suffer from the leaching of nitrate because the soils were more permeable and more N was mineralized during the incubation compared to the Rothamsted soils.展开更多
A pot experiment was carried out with a clay loam in a green house. The results showed that soil microbial biomass C increased with the application of organic manure at the beginning of the experiment and then gradual...A pot experiment was carried out with a clay loam in a green house. The results showed that soil microbial biomass C increased with the application of organic manure at the beginning of the experiment and then gradually decreased with declining of the temperature. The soil biomass C increased at the tillering stage when the temperature gradually increased, and rose to the highest value at the anthesis stage, being about 554.9-794.4 mg C kg-1. The application of organic manure resulted in the highest increase in biomass C among the fertilization treatments while that of ammonium sulphate gave the lowest. At the harvest time the soil biomass C decreased to the presowing level. Like the soil biomass C the amount of biomass P was increased by the incorporation of organic manure and was the highest among the treatments, with the values of the check and ammonium sulphate treatments being the lowest. Meanwhile, the changing patterns of the C/P ratio of soil microbial biomass at stages of wheat growth are also described.展开更多
Abstract： Physical, chemical and biological soil properties in surface （0-5 cm） and subsurface soil （5-15 cm） were determined in a field experiment conducted with seven treatments consisted of different combinati...Abstract： Physical, chemical and biological soil properties in surface （0-5 cm） and subsurface soil （5-15 cm） were determined in a field experiment conducted with seven treatments consisted of different combinations of fertilizer N （0, 100 and 200 kg N ha^-1）, P （0, 22 and 44 kg P2O5 ha^-1） and K （0, 41 and 82 kg K2O ha^-1） applied both to summer-grown maize （Zea mays L.） and winter-grown wheat （Triticum aestivum L.） crops continuously for 37 years under irrigated subtropical conditions. Application of N, P and K significantly increased water stable aggregates and had profound effects in increasing the mean weight diameter as well as the formation of macro-aggregates, which were highest in both surface （81%） and subsurface （74%） soil layers with application of 100 kg N ＋ 22 kg P2O5 ＋ 41 kg K2O ha^-1 （N100P22K41）. The N100P22K41 treatment also enhanced total organic C （TOC） from 4.4 g kg^-1 in no-NPK control to 4.8 g kg^-1in surface layer and from 3.3 to 4.1 g kg1 in subsurface layer leading to the 20% higher TOC stocks in 0-15 cm soil. The labile C and N fractions such as water soluble C, particulate and light fraction organic matter, potentially mineralizable N and microbial biomass were also highest under the optimized balanced application of N100P22K41. Relatively higher increase in all labile fractions of C and N as proportion of TOC and total N, respectively suggested that these are potential indicators to reflect changes in management practices long before changes in TOC and TN are detectable. These results demonstrated that optimized balanced application of N, P and K is crucial for improving soil health ensuring long-term sustainability of farming systems in semiarid subtropical soils.展开更多
This paper presents a method for creating modificable quartic and quintic curves with shape parameters. The curves can achieve C 2 even C 3 continuity and unify both interpolation and approximation to the control poin...This paper presents a method for creating modificable quartic and quintic curves with shape parameters. The curves can achieve C 2 even C 3 continuity and unify both interpolation and approximation to the control points without solving a system of equations or inserting additional control points. They have the local properties like the cubic B spline. Besides, the quintic curve would be able globally to tend the control polygon.展开更多
This study investigates changes in summer water vapor transport(WVT) over East Asia under 1.5°C and 2.0°C global warming(GW) for the +4.5 and +8.5 W m-2 Representative Concentration Pathway(RCP) scenarios(RC...This study investigates changes in summer water vapor transport(WVT) over East Asia under 1.5°C and 2.0°C global warming(GW) for the +4.5 and +8.5 W m-2 Representative Concentration Pathway(RCP) scenarios(RCP4.5 and RCP8.5, respectively). Of the 27 models used, 18 show better skill in simulating the climatological summer WVT over East Asia of the present day. Of those 18, 13 reach 1.5°C and 2.0°C GW for the two RCPs. Based on these 13 models, results show that — relative to the present day-th e summer WVT is enhanced over East Asia under 1.5°C and 2.0°C GW for RCP4.5 and RCP8.5. The inte r-model consistency is higher under 2.0°C GW. Increased water vapor content favors the enhanced WVT over both southern and northern East Asia, while lower-level circulation contributes to the enhanced WVT over southern East Asia. Compared to 1.5°C GW, th e summer WVT under 2.0°C GW is further enhanced over most of East Asia for RCP4.5. For RCP8.5, the summer WVT is also further enhanced over southern East Asia, while this is not the case over northern East Asia. Under the additional 0.5°C GW, the changes in summer WVT, with low in ter-model consistency, are closely related to anomalous lower-level circulation. Precipitation increases over the East China Sea to southern Japan, the Korean Peninsula, and North China, for both RCP4.5 and RCP8.5. However, the changes in precipitation over the South China Sea and Northeast China are different for the two RCPs. This is connected to the difference in the changes of WVT divergence.展开更多
The Paleocene coals of the Salt Range in the Punjab Province of Pakistan have great economic potential;however,their trace element and stable isotopic characteristics have not been studied in detail except for a few s...The Paleocene coals of the Salt Range in the Punjab Province of Pakistan have great economic potential;however,their trace element and stable isotopic characteristics have not been studied in detail except for a few sporadic samples.In this study,a total of 59 coal samples of which 14 are obtained from open cast mines have been investigated for elemental composition andδ^(13)C-δ^(15)N isotopic signatures.Average contents of trace elements such as Co,Cr,Cu,Pb,Sr,Th,U,V,and Zn are 7.4,41.7,11.2,12.5,90.2,4.0,1.9,128,and 31.1 mg/kg,respectively.These values,when compared with the World Coal Clarke values,were relatively higher in low-rank coals in comparison with Clarke values for brown coals.Likewise,As(20.4 mg/kg),Co(6.6 mg/kg),Cr(22.4 mg/kg),Cu(^(13).3 mg/kg),Pb(19.2 mg/kg),Sr(^(15)4.7 mg/kg),Th(2.5 mg/kg),V(47.8 mg/kg),and Zn(75.1 mg/kg)were significantly higher in the sub-bituminous to bituminous coals of the Salt Range.Mineralogical analysis,based on X-ray diffraction and energy dispersive X-ray spectroscopy,revealed that the studied samples contain illite,kaolinite calcite,gypsum,pyrite,and quartz.Elemental affinity with organic and inorganic phases of coals calculated by an indirect statistical approach indicated a positive association of ash content with Ag,Al,Co,Cr,Cs,Cu,Mn,P,Rb,Pb,Th,U,and V,suggesting the presence of inorganic components in studied coals.However,As,Fe,Sr,and Zn exhibit negative correlations that imply their association with the organic fraction.Theδ^(13)C andδ^(15)N isotopic range and average−24.94‰to−25.86‰(−25.41‰)and−2.77‰to 3.22‰(0.96‰),respectively,reflecting 3C type modern terrestrial vegetation were common in the palaeomires of studied coal seams.In addition,the trivial variations of 0.92‰and 0.45‰among^(13)C and^(15)N values can be attributed to water level fluctuations and plant assemblies.展开更多
The recently discovered tetragonal, monoclinie and orthorhombic polymorphs of M3N4 （M=C, Si, Sn） are in- vestigated by using first-principles calculations. A set of anisotropic elastic quantities, i.e., the bulk and...The recently discovered tetragonal, monoclinie and orthorhombic polymorphs of M3N4 （M=C, Si, Sn） are in- vestigated by using first-principles calculations. A set of anisotropic elastic quantities, i.e., the bulk and shear moduli, Young＇s modulus, Poisson ratio, H/G ratio and rickets hardness of M3N4 （M=C, Si, Sn） are predicted. The quasi-harmonic Debye model, assuming that the solids are isotopic, may lead to large errors for the non-cubic crystals. The thermal effects are obtained by the traditional quasi-harmonic approach. The dependences of heat capacity, thermal expansion coefficient and Debye temperature on temperature and pressure are systematically discussed in the pressure range of 0 IOGPa and in the temperature range of 0-1100 K. More importantly, o- C3N4 is a negative thermal expansion material. Our results may have important consequences in shaping the understanding of the fundamental properties of these binary nitrides.展开更多
Studies on structure-activity relationship of phenothiazines (PTZs) forinhibition of protein kinase C (PKC) and reversal of multidrug resistance (MDR) has been made invitro. The results showed that the order of potenc...Studies on structure-activity relationship of phenothiazines (PTZs) forinhibition of protein kinase C (PKC) and reversal of multidrug resistance (MDR) has been made invitro. The results showed that the order of potency of reversal effect of PTZs on MDR is as follows:2-COC_3 H_7 > 2-CF_3 > 2-COCH_3 > H. The type of piperazinyl substitution also significantlyaffected potency against MDR. The results show the order: CH_3 > COOC_2 H_5 > C_2 H_4 OH. Inaddition, PKC plays a marked role in diverse cellular process including MDR. Some derivatives of PTZwas tested for inhibition of PKC, of which PTZ11 showed the highest inhibitory effect of MDR andPKC, implying a potential reversal agent of MDR for tumor therapy in the future. We also tried toexplore the possible binding model of PTZs to PKC. Our molecular-modeling study preliminarilysuggests how these PTZs bind to PKC and provides a structural basis for the design of high affinityPKC-modulator. The infor-mation may be used in the rational design of more effective drugs.展开更多
基金financially supported by the National Natural Science Foundation of China(No.62105076)the Innovation Group of Guizhou University(No.[2024]08)+2 种基金the Platform of Science and Technology and Talent Team Plan of Guizhou Province(No.GCC[2023]007)the Guizhou Provincial Basic Research Program(No.ZK[2021]327)the Fok Ying Tung Education Foundation(No.171095)。
文摘Because of tempting magnetic-dielectric synergies and interfacial effects,designing a simple and low-cost route for producing multidimensional carbon-based magnetic nanocomposites is very important for the development of microwave absorbers(MAs).In this paper,a facile and propagable Ni-nitrilotriacetic acid chelate(NAC)derived strategy was proposed to selectively fabricate zero-dimensional(0D)/one-dimensional(1D)porous Ni/C magnetic heterostructured nanorods(MHNRs)consisting of 1D carbon nanorod,lots of pores and 0D Ni nanoparticles via a combined hydrothermal and thermally treated methods.The porous Ni/C MHNRs displayed the progressively improved Ni and C crystallinity by controlling the temperature,which resulted in the tunable electromagnetic and microwave absorption properties(MAPs).Additionally,0D/1D porous CoNi/C and Co/C MHNRs could be selectively produced through this strategy by adopting CoNi-NAC and Co-NAC as precursors.Benefiting from desirable interface and magnetic/dielectric synergies,the acquired 0D/1D porous Ni/C,CoNi/C and Co/C MHNRs presented excellent MAPs and certain corrosion resistance properties.In especial,Co/C MHNRs displayed a strong absorption capacity(−47.89 dB),an ultrawide effective absorption bandwidth(8.40 GHz)and small matching thicknesses(∼2 mm),which were a desirable candidate for MAs.Consequently,a facile,low-cost and propagable metal-NAC derived strategy was proposed to synthesize 0D/1D porous carbon-based MHNRs,which presented an alternative technique to develop lightweight efficient MAs.
基金support from the National Nature Science Foundation of China(Grant No.52273256).
文摘Exploring electrode materials with larger capacity,higher power density and longer cycle life was critical for developing advanced flexible lithium-ion batteries(LIBs).Herein,we used a controlled two-step method including electrospraying followed with calcination treatment by CVD furnace to design novel electrodes of Si/Si_(x)/C and Sn/C microrods array consisting of nanospheres on flexible carbon cloth substrate(denoted as Si/Si_(x)/C@CC,Sn/C@CC).Microrods composed of cumulated nanospheres(the diameter was approximately 120 nm)had a mean diameter of approximately 1.5μm and a length of around 4.0μm,distributing uniformly along the entire woven carbon fibers.Both of Si/Si/Si_(x)/C@CC and Sn/C@CC products were synthesized as binder-free anodes for Li-ion battery with the features of high reversible capacity and excellent cycling.Especially Si/Six/C electrode exhibited high specific capacity of about 1750 mA∙h∙g^(−1)at 0.5 A∙g^(−1)and excellent cycling ability even after 1050 cycles with a capacity of 1388 mA∙h∙g^(−1).Highly flexible Si/Si_(x)/C@CC//LiCoO_(2)batteries based on liquid and solid electrolytes were also fabricated,exhibiting high flexibility,excellent electrical stability and potential applications in flexible wearable electronics.
文摘Hepatitis C virus(HCV)infection has been increasingly associated with cardio-vascular complications,particularly atherosclerosis and cardiomyopathy,in addition to its primary hepatic effects.Studies indicate a higher prevalence of carotid atherosclerosis in patients with chronic hepatitis C infection,with viral load and steatosis emerging as independent risk factors.HCV-related athero-sclerosis appears to develop through complex processes involving endothelial dysfunction,inflammation,oxidative stress,and immune dysregulation.Key cytokines,including tumor necrosis factor-alpha and interleukin-6,increase inflammatory responses,while oxidative stress markers,such as malondial-dehyde,are associated with an increased risk of atherogenesis.In addition,HCV infection has been linked to cardiomyopathy.Direct viral effects,including HCV replication within cardiomyocytes and cytotoxicity induced by viral proteins,lead to myocardial injury and functional decline.Indirectly,HCV triggers immune-mediated damage,with heightened pro-inflammatory cytokines exacerbating cardiomyocyte apoptosis and fibrosis.Furthermore,HCV infection promotes a procoagulant imbalance,as evidenced by elevated factor VIII levels and thrombin potential,contributing to the increased cardiovascular risk.While substantial evidence indicates a relationship between HCV and cardiovascular disease,further research is needed to establish causality and guide therapeutic interventions.
基金National Key R&D Program of China,Grant/Award Number:2021YFF0703200Key Technology Fund of the National Institutes for Food and Drug Control,Grant/Award Number:GJJS-2022-1-5。
文摘Experimental mice play a critical role in biomedical research.The phenotype and application of different substrains vary due to genetic differentiation and variation.To ensure validity and reliability of results,it is imperative to adhere to standardized experiments and controls.This paper objectively reviews the origin,differentiation,and phenotypic and genetic differences between the C57BL/6 and BALB/c mouse substrains.Furthermore,an optimal selection strategy is proposed based on the genetic quality control technology to facilitate the precise application of these two mouse substrains.
文摘The use of conventional herbal medicines is a rapidly expanding phenomenon in developed nations. For instance, 30%–50% of all drug use in China is attributed to traditional herbal preparations. Current study evaluated the antioxidant (DPPH, FRAP), total phenolic and flavonoid content, antibacterial activity, and DNA damage protective potential of aqueous and methanolic extracts obtained from the aerial parts and roots of Cymbocarpum wiedemannii Boiss., an endemic plant in Turkey. In antioxidant analyses, the methanolic extract of the aerial parts showed the highest %DPPH (73.38) and IC50 (3.46 mg/mL) values. The FRAP analysis revealed the highest iron-reducing capacity in the methanolic extract of the aerial parts (108.10 ± 0.11 mg FeSO4/mL). The aqueous extract of the aerial parts exhibited the highest total phenolic content (1.69 ± 0.02 mg gallic acid/mL), while the methanolic extract of the aerial parts had the highest total flavonoid content (13.53 ± 0.09 mg rutin/mL). Antibacterial activity tests showed no significant effect at a concentration of 1 mg/mL for the samples. DNA protective effects were tested on pBR322 plasmid DNA, demonstrating that both aerial and root extracts could protect DNA from Fenton reaction-induced damage. In conclusion, C. wiedemannii exhibits potential bioactive properties, particularly in terms of its antioxidant and DNA protective effects.
基金supported by the National Natural Science Foundation of China(32160503)the Earmarked Fund for Jiangxi Agriculture Research System,China(JXARS-01)the National Key R&D Program of China(2023YFD2301303).
文摘Straw return has demonstrated significant potential for enhancing carbon(C)sequestration and nitrogen(N)uptake while concurrently promoting plant productivity.However,the specific transport and distribution of C produced by photosynthesis and exogenous N within the rice plant-soil system under straw return remains unclear.A long-term straw return pot trial experiment was conducted in a double cropping rice system,incorporating treatments of inorganic fertilizer application with straw removal(F),straw burning and ash return with reducing inorganic fertilizers(SBR),and straw return with reducing inorganic fertilizers(SR)to investigate C sequestration and exogenous N uptake using ^(13)C pulse and ^(15)N isotope tracer techniques.The SR treatment had significantly higher soil ^(13)C abundance,by 24.4 and 25.4%,respectively,^(13)C concentrations in aboveground plant parts,by 18.4 and 35.8%respectively,and ^(15)N concentrations in rice panicles,by 12.8 and 34.3%than the SBR and F treatments.This enhancement contributed to a higher total organic C concentration and increased rice grain yield in the SR treatment.Furthermore,the SR treatment had significantly higher photosynthetic C,by 9.8%,which was directly transferred to soil C.The SR treatment had a higher distribution of photosynthetic C in the leaves and stems,but a lower distribution in the panicle compared to the SBR treatment.This finding is advantageous for sequestering photosynthetic C into the soil through straw return;conversely,opposite trends were observed in ^(15)N distribution.In addition,rice plants in the SR treatment had increased N uptake from urea and soil N sources,enhancing N recovery by 9.2 and 12.5%,respectively,and reducing soil N residues.Correlation analysis showed that the SR treatment increased the concentrations of ^(13)C in leaves and roots while decreasing the ^(15)N abundance in all rice organs,thereby contributing to an increase in rice yield.The partial least square path model suggested that the increase in rice yield under the SR treatment was primarily linked to ^(13)C accumulation within the rice plant-soil system.The results suggest that straw return increases the sequestration of photosynthetic C and exogenous N in the rice plant-soil system and increases N utilization efficiency,which subsequently improves both rice and soil productivity.
文摘The antioxidant and anti-wrinkle firming effects of a combination of vitamin C(Vc)and black Ganoderma lucidum extract was evaluted.Through the DPPH radical scavenging model and elastase inhibition model,this research investigates the impact of these substances individually and in combination on antioxidant capabilities and anti-wrinkle firming effects.The results demonstrate that the combination of Vc and black Ganoderma lucidum extract exhibits significant antioxidant abilities at various concentrations,and is more effective than when each is used separately,indicating a synergistic interaction between them.Additionally,the combination also shows significant inhibition of elastase,suggesting potential applications in delaying the aging process of the skin.Furthermore,highperformance liquid chromatography(HPLC)was used to determine if reactions occur among the components of the mixture.The findings reveal that the concentration of Vc in the mixture is very close to the theoretical concentration and relatively stable,suggesting that the components function independently.A quantitative analysis using the Bliss independence model further confirms the synergistic effects of Vc and black Ganoderma lucidum extract at specific ratios,providing a scientific basis for the development of efficacious cosmetic products.
文摘The aim of this study was to assess the seroprevalence of viral hepatitis B and C and co-infection with HIV among volunteer blood donors at the blood sampling and distribution depot (BSDD) in Ouahigouya. Patients and methods: Our study population consisted of all volunteer blood donors who had donated during a 2-year period from 1 January 2019 to 31 December 2020. Samples were taken from patients with no contraindications and serological tests were performed using ELISA tests. HBsAg, HCV-Ac and HIV serology were tested. All samples reactive for HIV, HBV and HCV were retested for confirmation using a second enzyme-linked immunosorbent assay. A result was considered positive if both the first and second tests were positive. Results: In two years, the Ouahigouya BSDD recorded 9726 donations, including 7983 new donors and 1743 former donors. The average age of donors was 25.59 years, with a sex ratio of 3.4. The seroprevalence of HBV, HCV and HIV was 7.31%, 3.10% and 2.12% respectively. HBV-HCV co-infection was found in 0.32% of cases, HIV-HBV, HIV-HCV, and HIV-HBV-HCV co-infection were found in 0.25%, 0.09% and 0.04% respectively. Conclusion: The seroprevalence of viral hepatitis B and C remains high among volunteer blood donors in Ouahigouya, although a decline in seroprevalence appears to be on the horizon.
基金Ho Chi Minh City University of Technology(HCMUT),VNU-HCM for supporting this study.
文摘Vitamin C,a potent antioxidant with broad therapeutic applications,is limited by rapid degradation under environmental stressors,which compromises its stability and bioactivity.This study addresses these limitations by formulating a double nano-emulsion(W/O/W)system incorporating macadamia oil and tea tree oil,using homogenization and phase inversion temperature(PIT)techniques.Comprehensive physicochemical charac-terization,including droplet size,polydispersity index(PDI),zeta potential,turbidity,Fourier transform infrared spectroscopy(FTIR),and SEM,was conducted alongside stability assessments under varying pH,temperature,and storage conditions.The optimized nano-emulsions exhibited nanoscale droplet sizes(10-40 nm),low PDI values(indicating high uniformity),and robust stability.Interestingly,the formulation with 2%W/O loading,with a particle size of 11.57 nm and a PDI of 0.04,demonstrated an antioxidant capacity of 4622.62μg ascorbic acid equivalents(AA)/g,which was significantly higher(p<0.05)compared to both natural oils(macadamia oil:20.91μg AA/g,tea tree oil:16.86μg AA/g)and a 10%Vitamin C aqueous solution(592.94μg AA/g).FTIR analysis confirmed the molecular integrity of Vitamin C and its successful encapsulation with macadamia and tea tree oils,while SEM images revealed uniformly spherical and well-dispersed droplets.Moreover,the formulation retained its structural integrity and antioxidant functionality under diverse pH and thermal conditions.These findings underscore the potential of double nano-emulsion systems to overcome the stability challenges of Vitamin C,offering a promising approach to enhance its bioavailability and therapeutic performance in phar-maceutical and cosmetic applications.
基金supported by the National Natural Science Foundation of China(Grant No.12175318)the Natural Science Foundation of Guangdong Province of China(Grant No.2023A1515011704)。
文摘The observations of fully-charm tetraquark states in the LHCb,CMS,and ATLAS experiments suggested the existence of hadronic molecules of two-charmonium states,which may also imply bound states in the threecharmonium systems.In this work,we study the possible bound states in the triple-ηcand triple-J/ψsystems with J^(PC)=0^(-+)and 1^(--),respectively.In quantum chromodynamics sum rules,we calculate the two-point correlation functions and spectral functions up to the dimension-four gluon condensate.We use the iterative dispersion relation approach to deal with the five-loop banana integrals,which significantly improves computational efficiency.Our results show that the masses of triple-ηcand triple-J/ψstates lie below the corresponding mass thresholds,supporting the existence of such three-body bound states.
基金Supported by Henan Province Key Research and Development Program,No.231111311000Henan Provincial Science and Technology Research Project,No.232102310411+2 种基金Henan Province Medical Science and Technology Key Project,No.LHGJ20220566 and No.LHGJ20240365Henan Province Medical Education Research Project,No.WJLX2023079Zhengzhou Medical and Health Technology Innovation Guidance Program,No.2024YLZDJH022.
文摘This study highlights the importance of identifying and addressing risk factors associated with wound complications following transtibial amputation in diabetic patients.These amputations,often necessitated by severe diabetic foot ulcers,carry significant risks of postoperative complications such as infection and delayed wound healing.Elevated hemoglobin A1c levels,indicative of poor glycemic control,and a history of kidney transplantation,due to required immunosuppressive therapy,are key factors influencing these outcomes.This paper emphasizes the need for enhanced glycemic management and personalized postoperative care,particularly for immunocompromised individuals,to minimize complications and improve patient prognosis.Future research should focus on prospective studies to validate targeted interventions and optimize care strategies,ultimately aiming to reduce the healthcare burden associated with diabetic foot complications.
文摘The Hastelloy C22 coatings on Q235 steel substrate were produced by high power diode laser cladding technique. Their corrosion behaviors in static and cavitation hydrochloric, sulfuric and nitric acid solutions were investigated. The electrochemical results show that corrosion resistance of coatings in static acid solutions is higher than that in cavitation ones. In each case, coating corrosion resistance in descending order is in nitric, sulfuric and hydrochloric acid solutions. Obvious erosion-corrosion morphology and serious intercrystalline corrosion of coating are noticed in cavitation hydrochloric acid solution. This is mainly ascribed to the aggressive ions in hydrochloric acid solution and mechanical effect from cavitation bubbles collapse. While coating after corrosion test in cavitation nitric acid solution shows nearly unchanged surface morphology. The results indicate that the associated action of cavitation and property of acid solution determines the corrosion development of coating. Hastelloy C22 coating exhibits better corrosion resistance in oxidizing acid solution for the stable formation of dense oxide film on the surface.
文摘A study was performed on the long-term effect of straw incorporation on soil microbial biomass C contents, C and N dynamics in both Rothamsted and Woburn soils. The results showed that for both soils,the microbial biomass C contents were significantly different among all the treatments, and followed the sequence in treatments of straw chopped and incorporated into 10 cm (CI10) > straw burnt and incorporated into 10 cm (BI10) > straw chopped and incorporated into 20 cm (CI20) > straw burnt and incorporated into 20 cm (BI20). Laboratory incubation of soils showed that the cumulative CO2 evolution was closely related to the soil microbial biomass C content. Carbon dioxide evolution rates (CO2-C, μg (g d) -1 ) decreased rapidly in the first two weeks’ incubation, then decreased more slowly. The initial K2SO4-extractable NH4-N and NO3-N contents were low and similar in all the treatments, and all increased gradually with the incubation time. However, net N immobilization was observed in chopped treatments for Rothamsted soils during the first 4 weeks. Nevertheless, more N mineralization occurred in neatment CI10 than any other treatment at the end of incubation for both soils. The Woburn soils could more easily suffer from the leaching of nitrate because the soils were more permeable and more N was mineralized during the incubation compared to the Rothamsted soils.
文摘A pot experiment was carried out with a clay loam in a green house. The results showed that soil microbial biomass C increased with the application of organic manure at the beginning of the experiment and then gradually decreased with declining of the temperature. The soil biomass C increased at the tillering stage when the temperature gradually increased, and rose to the highest value at the anthesis stage, being about 554.9-794.4 mg C kg-1. The application of organic manure resulted in the highest increase in biomass C among the fertilization treatments while that of ammonium sulphate gave the lowest. At the harvest time the soil biomass C decreased to the presowing level. Like the soil biomass C the amount of biomass P was increased by the incorporation of organic manure and was the highest among the treatments, with the values of the check and ammonium sulphate treatments being the lowest. Meanwhile, the changing patterns of the C/P ratio of soil microbial biomass at stages of wheat growth are also described.
文摘Abstract： Physical, chemical and biological soil properties in surface （0-5 cm） and subsurface soil （5-15 cm） were determined in a field experiment conducted with seven treatments consisted of different combinations of fertilizer N （0, 100 and 200 kg N ha^-1）, P （0, 22 and 44 kg P2O5 ha^-1） and K （0, 41 and 82 kg K2O ha^-1） applied both to summer-grown maize （Zea mays L.） and winter-grown wheat （Triticum aestivum L.） crops continuously for 37 years under irrigated subtropical conditions. Application of N, P and K significantly increased water stable aggregates and had profound effects in increasing the mean weight diameter as well as the formation of macro-aggregates, which were highest in both surface （81%） and subsurface （74%） soil layers with application of 100 kg N ＋ 22 kg P2O5 ＋ 41 kg K2O ha^-1 （N100P22K41）. The N100P22K41 treatment also enhanced total organic C （TOC） from 4.4 g kg^-1 in no-NPK control to 4.8 g kg^-1in surface layer and from 3.3 to 4.1 g kg1 in subsurface layer leading to the 20% higher TOC stocks in 0-15 cm soil. The labile C and N fractions such as water soluble C, particulate and light fraction organic matter, potentially mineralizable N and microbial biomass were also highest under the optimized balanced application of N100P22K41. Relatively higher increase in all labile fractions of C and N as proportion of TOC and total N, respectively suggested that these are potential indicators to reflect changes in management practices long before changes in TOC and TN are detectable. These results demonstrated that optimized balanced application of N, P and K is crucial for improving soil health ensuring long-term sustainability of farming systems in semiarid subtropical soils.
文摘This paper presents a method for creating modificable quartic and quintic curves with shape parameters. The curves can achieve C 2 even C 3 continuity and unify both interpolation and approximation to the control points without solving a system of equations or inserting additional control points. They have the local properties like the cubic B spline. Besides, the quintic curve would be able globally to tend the control polygon.
基金jointly supported by the National Key R&D Program of China [grant number 2017YFA0603802]the National Natural Science Foundation of China [grant numbers 41421004,41325018,and 41805062]
文摘This study investigates changes in summer water vapor transport(WVT) over East Asia under 1.5°C and 2.0°C global warming(GW) for the +4.5 and +8.5 W m-2 Representative Concentration Pathway(RCP) scenarios(RCP4.5 and RCP8.5, respectively). Of the 27 models used, 18 show better skill in simulating the climatological summer WVT over East Asia of the present day. Of those 18, 13 reach 1.5°C and 2.0°C GW for the two RCPs. Based on these 13 models, results show that — relative to the present day-th e summer WVT is enhanced over East Asia under 1.5°C and 2.0°C GW for RCP4.5 and RCP8.5. The inte r-model consistency is higher under 2.0°C GW. Increased water vapor content favors the enhanced WVT over both southern and northern East Asia, while lower-level circulation contributes to the enhanced WVT over southern East Asia. Compared to 1.5°C GW, th e summer WVT under 2.0°C GW is further enhanced over most of East Asia for RCP4.5. For RCP8.5, the summer WVT is also further enhanced over southern East Asia, while this is not the case over northern East Asia. Under the additional 0.5°C GW, the changes in summer WVT, with low in ter-model consistency, are closely related to anomalous lower-level circulation. Precipitation increases over the East China Sea to southern Japan, the Korean Peninsula, and North China, for both RCP4.5 and RCP8.5. However, the changes in precipitation over the South China Sea and Northeast China are different for the two RCPs. This is connected to the difference in the changes of WVT divergence.
基金the Higher Education Commission Pakistan for funding the lab research under its International Research Support Initiative Program (IRSIP) programthe Department of Environmental Science, Quaid-i-Azam University, Islamabad (especially Environmental Hydro geochemistry Lab)the Environment & Sustainability Institute and Camborne School of Mines, University of Exeter, for technical support in conducting lab analysis
文摘The Paleocene coals of the Salt Range in the Punjab Province of Pakistan have great economic potential;however,their trace element and stable isotopic characteristics have not been studied in detail except for a few sporadic samples.In this study,a total of 59 coal samples of which 14 are obtained from open cast mines have been investigated for elemental composition andδ^(13)C-δ^(15)N isotopic signatures.Average contents of trace elements such as Co,Cr,Cu,Pb,Sr,Th,U,V,and Zn are 7.4,41.7,11.2,12.5,90.2,4.0,1.9,128,and 31.1 mg/kg,respectively.These values,when compared with the World Coal Clarke values,were relatively higher in low-rank coals in comparison with Clarke values for brown coals.Likewise,As(20.4 mg/kg),Co(6.6 mg/kg),Cr(22.4 mg/kg),Cu(^(13).3 mg/kg),Pb(19.2 mg/kg),Sr(^(15)4.7 mg/kg),Th(2.5 mg/kg),V(47.8 mg/kg),and Zn(75.1 mg/kg)were significantly higher in the sub-bituminous to bituminous coals of the Salt Range.Mineralogical analysis,based on X-ray diffraction and energy dispersive X-ray spectroscopy,revealed that the studied samples contain illite,kaolinite calcite,gypsum,pyrite,and quartz.Elemental affinity with organic and inorganic phases of coals calculated by an indirect statistical approach indicated a positive association of ash content with Ag,Al,Co,Cr,Cs,Cu,Mn,P,Rb,Pb,Th,U,and V,suggesting the presence of inorganic components in studied coals.However,As,Fe,Sr,and Zn exhibit negative correlations that imply their association with the organic fraction.Theδ^(13)C andδ^(15)N isotopic range and average−24.94‰to−25.86‰(−25.41‰)and−2.77‰to 3.22‰(0.96‰),respectively,reflecting 3C type modern terrestrial vegetation were common in the palaeomires of studied coal seams.In addition,the trivial variations of 0.92‰and 0.45‰among^(13)C and^(15)N values can be attributed to water level fluctuations and plant assemblies.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61475132 and 61501392
文摘The recently discovered tetragonal, monoclinie and orthorhombic polymorphs of M3N4 （M=C, Si, Sn） are in- vestigated by using first-principles calculations. A set of anisotropic elastic quantities, i.e., the bulk and shear moduli, Young＇s modulus, Poisson ratio, H/G ratio and rickets hardness of M3N4 （M=C, Si, Sn） are predicted. The quasi-harmonic Debye model, assuming that the solids are isotopic, may lead to large errors for the non-cubic crystals. The thermal effects are obtained by the traditional quasi-harmonic approach. The dependences of heat capacity, thermal expansion coefficient and Debye temperature on temperature and pressure are systematically discussed in the pressure range of 0 IOGPa and in the temperature range of 0-1100 K. More importantly, o- C3N4 is a negative thermal expansion material. Our results may have important consequences in shaping the understanding of the fundamental properties of these binary nitrides.
文摘Studies on structure-activity relationship of phenothiazines (PTZs) forinhibition of protein kinase C (PKC) and reversal of multidrug resistance (MDR) has been made invitro. The results showed that the order of potency of reversal effect of PTZs on MDR is as follows:2-COC_3 H_7 > 2-CF_3 > 2-COCH_3 > H. The type of piperazinyl substitution also significantlyaffected potency against MDR. The results show the order: CH_3 > COOC_2 H_5 > C_2 H_4 OH. Inaddition, PKC plays a marked role in diverse cellular process including MDR. Some derivatives of PTZwas tested for inhibition of PKC, of which PTZ11 showed the highest inhibitory effect of MDR andPKC, implying a potential reversal agent of MDR for tumor therapy in the future. We also tried toexplore the possible binding model of PTZs to PKC. Our molecular-modeling study preliminarilysuggests how these PTZs bind to PKC and provides a structural basis for the design of high affinityPKC-modulator. The infor-mation may be used in the rational design of more effective drugs.
