For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflect...For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.展开更多
Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy...Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation.展开更多
Through the analysis on the meanings and features as well as the ad- vantages of the third-party logistics for agricultural products, the quantization index system for the selection of third-party logistics providers ...Through the analysis on the meanings and features as well as the ad- vantages of the third-party logistics for agricultural products, the quantization index system for the selection of third-party logistics providers for agricultural products was constructed based on the system comprehensive evaluation theory. Analytic hierar- chy process (AHP) was used to determine the weight of the index system of each level, and AHP and fuzzy comprehensive evaluation method were used to determine the selection steps for the third-party logistics providers for agricultural products. The method was proved to be scientific and reasonable through calculation examples.展开更多
ZnO nanoparticles were synthesized via a direct precipitation method followed by a hetero- geneous azeotropic distillation and calcination processes, and then characterized by X-ray power diffraction, scanning electro...ZnO nanoparticles were synthesized via a direct precipitation method followed by a hetero- geneous azeotropic distillation and calcination processes, and then characterized by X-ray power diffraction, scanning electron microscopy, transmission electron microscopy, and ni- trogen adsorption-desorption measurement. The effects of Pt-loading amount, calcination temperature, and sacrificial reagents on the present ZnO suspension were investigated, photocatalytic H2 evolution efficiency from the The experimental results indicate that ZnO rianoparticles calcined at 400℃ exhibit the best photoactivity for the H2 production in comparison with the samples calcined at 300 and 500℃, and the photoeatalytie H2 production efficiency from a methanol solution is much higher than that from a triethanolamine solution. It can be ascribed to the oxidization of methanol also contributes to the H2 production during the photochemical reaction process. Moreover, the photocatalytic mechanism for the H2 production from the present ZnO suspension system containing methanol solution is also discussed in detail.展开更多
Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high f...Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems,particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production.Of particular potential value is the opportunity to use crude fibre concentrates as ’functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates.展开更多
Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect...Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF).展开更多
Temporary plugging agent(TPA)is widely used in many fields of petroleum reservoir drilling and production,such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturin...Temporary plugging agent(TPA)is widely used in many fields of petroleum reservoir drilling and production,such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturing operations.The commonly used TPA mainly includes hard particles,fibers,gels,and composite systems.However,current particles have many limitations in applications,such as insufficient plugging strength and slow degradation rate.In this paper,a degradable pre-formed particle gel(DPPG)was developed.Experimental results show that the DPPG has an excellent static swelling effect and self-degradation performance.With a decrease in the concentration of total monomers or cross-linker,the swelling volume of the synthesized DPPG gradually increases.However,the entire self-degradation time gradually decreases.The increase in 2-acrylamide-2-methylpropanesulfonic acid(AMPS)in the DPPG composition can significantly increase its swelling ratio and shorten the self-degradation time.Moreover,DPPG has excellent high-temperature resistance(150°C)and high-salinity resistance(200,000 mg/L NaCl).Core displacement results show that the DPPG has a perfect plugging effect in the porous media(the plugging pressure gradient was as high as 21.12 MPa),and the damage to the formation after degradation is incredibly minor.Therefore,the DPPG can be used as an up-and-coming TPA in oil fields.展开更多
The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were emplo...The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were employed to characterize the temporal trends and spatial patterns in farm production and five pertinent inputs of cultivated cropland, irrigation ratio, agricultural labor, machinery power and chemical fertilizer. Stochastic frontier production function was applied to quantify the dependence of the farm production on these inputs. The growth of farm production was decomposed to reflect the contributions by input growths and change in total factor productivity.. The change in total factor productivity was further decomposed into the changes in technology and in technical efficiency. The gross value of farm production in the region of study increased by 1.6 fold during 1980-1999. Among the five selected farm inputs, machinery power and chemical fertilizer increased by 1.8 and 2.8 fold, respectively. The increases in cultivated cropland, irrigated cropland, and agricultural labor were all less than 0.16 fold. The growth in the farm production was primarily contributed by the increase in the total factor productivity during 1980-1985, and by input growths after 1985. More than 80% of the contributions by input growths were attributed to the increased application of fertilizer and machinery. In the change of total factor productivity, the technology change dominated over the technical efficiency change in the study period except in the period of 1985-1990, implying that institution and investment played important roles in farm production growth. There was a decreasing trend in the technical efficiency in the region of study, indicating a potential to increase farm production by improving the technical efficiency in farm activities. Given the limited natural resources in the basin, the results of this study suggested that, for a sustainable growth of farm production in the area, efforts should be directed to technology progress and improvement in technical efficiency in the use of available resources.展开更多
The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both e...The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both economic and environmental terms.The cross-section data were obtained from the TALYS Evaluated Nuclear Data Library(TENDL).A thick target model was used to study the consumption of the target isotopes in the transmutation process.The transmutation yield was calculated using the highest beam intensity available with the China initiative accelerator-driven system.It was found that the light nuclide-induced spallation reaction can significantly reduce the radio toxicity of the investigated long-lived fission products.Using the transmutation target made of elemental LLFP and the proton beam with an intensity of 5 mA,the consumption of 90 Sr,93 Zr,107 Pd,or 137 Cs can reach approximately 500 g per year.展开更多
Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a...Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a fairly general condition on the weight dk= k-1 exp(lnβk),0≤β〈1.And in a sense,our results have reached the optimal form.展开更多
We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multipl...We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multiple parton interactions and gluon contributions is studied and found to be a possible source of the splitting of the particle yields as a function of p_T with respect to the multiplicity. No obvious particle species dependence of the splitting is observed.The multiplicity dependence of the ratios Kˉ/πˉ, K^+/π^+,/πˉ, p/π^+, and K_s^0 at mid-rapidity in p+ p collisions is found to follow a tendency similar to that in Au t Au collisions at (s_(NN))^(1/2) = 200 GeV at the Relativistic Heavy Ion Collider, indicating similar underlying initial production mechanisms despite the differences in the initial colliding systems.展开更多
To investigate the characteristics of hydrogen production by a novel fermentative hydrogen-producing bacterial strain B49 (AF481148 in EMBL), batch experiments are conducted under different conditions. Hydrogen produc...To investigate the characteristics of hydrogen production by a novel fermentative hydrogen-producing bacterial strain B49 (AF481148 in EMBL), batch experiments are conducted under different conditions. Hydrogen production has a correlation with cell growth and the consumption of glucose and soluble protein. The optimum pH for cell growth is 4.5±0.15. At acidic pH 4.0±0.15, the bacteria has the maximum accumulated hydrogen volume of 2382 ml/L culture and the maximum hydrogen evolution rate of 339.9 ml/L culture·h with 1% glucose. The optimum temperature for cell growth and hydrogen production is 35℃. In addition, fermentative hydrogen-producing bacterial strain B49 can generate hydrogen from the decomposition of other organic substrates such as wheat, soybean, corn, and potato. Moreover, it can also produce hydrogen from molasses wastewater and brewage wastewater, and hydrogen yields are 137.9 ml H 2/g COD and 49.9 ml H 2/g COD, respectively.展开更多
Sand production is one of the main obstacles restricting gas extraction efficiency and safety from marine natural gas hydrate(NGH)reservoirs.Particle migration within the NGH reservoir dominates sand production behavi...Sand production is one of the main obstacles restricting gas extraction efficiency and safety from marine natural gas hydrate(NGH)reservoirs.Particle migration within the NGH reservoir dominates sand production behaviors,while their relationships were rarely reported,severely constrains quantitative evaluation of sand production risks.This paper reports the optical observations of solid particle migration and production from micrometer to mesoscopic scales conditioned to gravel packing during depressurization-induced NGH dissociation for the first time.Theoretical evolutionary modes of sand migration are established based on experimental observations,and its implications on field NGH are comprehensively discussed.Five particle migration regimes of local borehole failure,continuous collapse,wormhole expansion,extensive slow deformation,and pore-wall fluidization are proved to occur during depressurization.The types of particle migration regimes and their transmission modes during depressurization are predominantly determined by initial hydrate saturation.In contrast,the depressurization mainly dominates the transmission rate of the particle migration regimes.Furthermore,both the cumulative mass and the medium grain size of the produced sand decrease linearly with increasing initial methane hydrate(MH)saturation.Discontinuous gas bubble emission,expansion,and explosion during MH dissociation delay sand migration into the wellbore.At the same time,continuous water flow is a requirement for sand production during hydrate dissociation by depressurization.The experiments enlighten us that a constitutive model that can illustrate visible particle migration regimes and their transmission modes is urgently needed to bridge numerical simulation and field applications.Optimizing wellbore layout positions or special reservoir treatment shall be important for mitigating sand production tendency during NGH exploitation.展开更多
[Objective] The paper to investigate the effects of pelleted total mixed ration of different particle size on production performance and serum biochemical index of fattening Hainan black goats.[Method] Thirty-six fatt...[Objective] The paper to investigate the effects of pelleted total mixed ration of different particle size on production performance and serum biochemical index of fattening Hainan black goats.[Method] Thirty-six fattening Hainan black goats with the same genetic backgrounds and similar initial weight of(19.02±0.22) kg were randomly divided into three treatments. Goats were fed with Juncao+concentrate(control group), pel-leted total mixed ration I(particle size 6 mm, experimental group I) and II(particle size 5 mm, experimental group II), respectively. The trial lasted 45 d.[Result](1) The final weight and daily gain of experimental group II were significantly higher than those of control group( P<0.05), and the daily gain of experimental group II was also higher than that of experimental group I(P<0.05);the feed intake of experimental group II was markedly higher than that of control group(P<0.05), but was significantly lower than that of experimental group I(P<0.05). The feed/gain ratio of experimental group II was significantly lower than those of control group and experimental group I(P<0.05).(2) The feed gain cost of experimental group II was markedly lower than that of control group(P<0.05), but the gross profit was significantly higher than those of control group and experimental group I(P<0.05).(3) Compared with the control group, the serum total protein content of experimental group II increased markedly( P<0.05) while the urea nitrogen level decreased(P>0.05).[Conclusion] The pelleted total mixed ration with the particle size of 5 mm obtained better fattening ef-fect, and obviously improved the serum total protein level.展开更多
Electrochemical ozone production(EOP) via water electrolysis represents an attractive method for the generation of high-purity O3. Herein, the X-PtZn/Zn-N-C electrocatalysts show a strong structural sensitive behavior...Electrochemical ozone production(EOP) via water electrolysis represents an attractive method for the generation of high-purity O3. Herein, the X-PtZn/Zn-N-C electrocatalysts show a strong structural sensitive behavior depends on the size of the PtZn nanoparticles and their EOP activity exhibits a volcano-type dependence for the O3 performance in neutral media. The 7.7-PtZn/Zn-N-C exhibits EOP current efficiency of 4.2%, and shows the prominent performance in the production of gaseous O3 with a value of 1647 ppb at 30 min, which is almost 4-fold compared to 2.2-Pt Zn/Zn-N-C. Based on the experiments and theoretical calculations, the performance of the EOP process was determined by the nanoparticle size-effect and the synergistic effect between the PtZn nanoparticles and atomically dispersed Zn-N-C. Furthermore, the fivemembered cyclic structure of O3 can be stabilized between the PtZn nanoparticle and the Zn-N-C support,indicating that O3 is produced at the interface.展开更多
Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arriva...Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arrivals, may compromise the observance of on-time supplies for some orders. The purpose of this paper is to evaluate the conditions of post-optimality for stochastic order rate governed production systems in order to observe OTD. Instead of a heuristic or a simulative exploration, a Cartesian-based approach is applied to developing the necessary and sufficient mathematical condition to solve the problem statement. The research result demonstrates that increasing </span><span style="font-family:Verdana;">speed of throughput reveals a latent capacity, which allows arrival orders </span><span style="font-family:Verdana;">above capacity limits to be backlog-buffered and rescheduled for OTD, exploiting the virtual manufacturing elasticity inherent to all production systems to increase OTD reliability of non JIT-based production systems.展开更多
Design change is an inevitable part of the product development process.This study proposes an improved binary multi‐objective PSO algorithm guided by problem char-acteristics(P‐BMOPSO)to solve the optimisation probl...Design change is an inevitable part of the product development process.This study proposes an improved binary multi‐objective PSO algorithm guided by problem char-acteristics(P‐BMOPSO)to solve the optimisation problem of complex product change plan considering service performance.Firstly,a complex product multi‐layer network with service performance is established for the first time to reveal the impact of change effect propagation on the product service performance.Secondly,the concept of service performance impact(SPI)is defined by decoupling the impact of strongly associated nodes on the service performance in the process of change affect propagation.Then,a triple‐objective selection model of change nodes is established,which includes the three indicators:SPI degree,change cost,and change time.Furthermore,an integer multi‐objective particle swarm optimisation algorithm guided by problem characteristics is developed to solve the model above.Experimental results on the design change problem of a certain type of Skyworth TV verify the effectiveness of the established optimisation model and the proposed P‐BMOPSO algorithm.展开更多
During the 29 th Chinese National Antarctic Research Expedition,spatial variations in nitrogen isotopic composition of particulate nitrogen(δ15NPN)and their controlling factors were examined in detail with regard to ...During the 29 th Chinese National Antarctic Research Expedition,spatial variations in nitrogen isotopic composition of particulate nitrogen(δ15NPN)and their controlling factors were examined in detail with regard to nitrate drawdown by phytoplankton and particulate nitrogen(PN)remineralization in the Prydz Bay and its adjacent areas.To better constrain the nitrogen transformations,the physical and chemical parameters,including temperature,salinity,nutrients,PN andδ15NPN in seawater column were measured from surface to bottom.In addition,the nitrogen isotopic fractionation factor of nitrate assimilation by phytoplankton in the mixed layer,and the nitrogen isotopic fractionation factor of PN remineralization below the mixed layer were estimated using Rayleigh model and Steady State model,respectively.Our results showed that suspended particles had its lowestδ15NPN in the surface layer,which was due to the preferential assimilation of 14 N in nitrate by phytoplankton.Theδ15NPN in the mixed layer of the Prydz Bay and its adjacent areas decreased from the inner shelf to the outer basin,ascribing to the effect of isotope fractionation during phytoplankton assimilation.In mixed layer,the spatial distribution ofδ15NPN associated with particulate organic matter(POM)production can be well interpreted according to Rayleigh model and Steady State model.The nitrogen isotope fractionation factor during phytoplankton assimilating nitrate was estimated as 10.0‰by Steady State model,which was more reasonable than that calculated by Rayleigh model.These results validate the previous reports of fractionation factor during nitrate assimilation by phytoplankton.Increasingδ15NPN with depth below the euphotic zone correlated with the decreasing PN contents,and it was attributed to preferential remineralization of 14 N in PN by bacteria.In subsurface and deep layer,theδ15NPN distributions also conformed to Rayleigh model and Steady State model during PN remineralization,with a fractionation factor of about 3.6‰and 3.2‰,respectively.It is the first time to estimate the fractionation factor during POM production and remineralization in the Prydz Bay and its adjacent areas.Such fractionation may provide a useful tool for the follow-up study of the nitrogen dynamics in the Southern Ocean.展开更多
Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate...Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.展开更多
Objective] This study was conducted to discuss growth characteristics and partial production and quality characters of different varieties, so as to provide can-didates for tobacco production as wel as a theoretical b...Objective] This study was conducted to discuss growth characteristics and partial production and quality characters of different varieties, so as to provide can-didates for tobacco production as wel as a theoretical basis for variety deployment in Guizhou. [Method] ‘K326’ was used as control, the experiment for variance analysis of growth characteristics and partial production and quality characters of dif-ferent tobacco varieties was carried out in Fengsan Town, Kaiyang County, Guizhou Province in 2015. [Result] GY8 grew faster in early stages and slower in late stages, the growth periods of GY2 (130 d) and GY5(129 d) were the longest, while those of Yun85 (121 d) and Yun87 (121 d) were the shortest; and GY2, GY5 and GY8 had larger plant heights, maximum leaf widths and maximum leaf areas, and Yun85, Yun87 and K326 showed larger stem girths and maximum leaf lengths. Yun87 exhibited lower natural incidences of diseases, while Yun85 and GY8 showed higher incidences of diseases. GY2, GY5 and GY8 had higher nicotine, total nitro-gen, K and Cl contents, while Yun85, Yun87 and K326 had higher total sugar and reducing sugar contents and higher total sugar/nicotine ratio. Yun85 and Yun87 showed better economic characters, while GY5 and GY8 showed poorer economic characters. [Conclusion] Yun85 and Yun87 have quality characters better than GY2 and GY8, field natural incidences of diseases lower than GY2 and GY8, and better economic characters, and thus could serve as candidates in future flue-cured tobac-co production in Guizhou.展开更多
基金supported by the Scientific Research Fund of Hunan Provincial Education Department(21B0070)the Natural Science Foundation of Jiangsu Province(BK20231452)+1 种基金the Fundamental Research Funds for the Central Universities(30922010809)the National Natural Science Foundation of China(11801591,11971195,12071171,12171107,12201207,12371072)。
文摘For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.
文摘Cells undergo metabolic reprogramming to adapt to changes in nutrient availability, cellular activity, and transitions in cell states. The balance between glycolysis and mitochondrial respiration is crucial for energy production, and metabolic reprogramming stipulates a shift in such balance to optimize both bioenergetic efficiency and anabolic requirements. Failure in switching bioenergetic dependence can lead to maladaptation and pathogenesis. While cellular degradation is known to recycle precursor molecules for anabolism, its potential role in regulating energy production remains less explored. The bioenergetic switch between glycolysis and mitochondrial respiration involves transcription factors and organelle homeostasis, which are both regulated by the cellular degradation pathways. A growing body of studies has demonstrated that both stem cells and differentiated cells exhibit bioenergetic switch upon perturbations of autophagic activity or endolysosomal processes. Here, we highlighted the current understanding of the interplay between degradation processes, specifically autophagy and endolysosomes, transcription factors, endolysosomal signaling, and mitochondrial homeostasis in shaping cellular bioenergetics. This review aims to summarize the relationship between degradation processes and bioenergetics, providing a foundation for future research to unveil deeper mechanistic insights into bioenergetic regulation.
基金Supported by the Natural Science Foundation of Guangxi Province(2011GXNSFB018061)the High-grade Scientific Research(Cultivation)Program of Qinzhou University(2014PY-SJ03,2014PY-SJ01)~~
文摘Through the analysis on the meanings and features as well as the ad- vantages of the third-party logistics for agricultural products, the quantization index system for the selection of third-party logistics providers for agricultural products was constructed based on the system comprehensive evaluation theory. Analytic hierar- chy process (AHP) was used to determine the weight of the index system of each level, and AHP and fuzzy comprehensive evaluation method were used to determine the selection steps for the third-party logistics providers for agricultural products. The method was proved to be scientific and reasonable through calculation examples.
基金This work was supported by the National Natural Science Foundation of China (No.20973128 and No.20871096), the National High Tech Research and Development Program (No.2006AA03Z344), and the Program for New Century Excellent Talents in University of China (No.NCET-07-0637).
文摘ZnO nanoparticles were synthesized via a direct precipitation method followed by a hetero- geneous azeotropic distillation and calcination processes, and then characterized by X-ray power diffraction, scanning electron microscopy, transmission electron microscopy, and ni- trogen adsorption-desorption measurement. The effects of Pt-loading amount, calcination temperature, and sacrificial reagents on the present ZnO suspension were investigated, photocatalytic H2 evolution efficiency from the The experimental results indicate that ZnO rianoparticles calcined at 400℃ exhibit the best photoactivity for the H2 production in comparison with the samples calcined at 300 and 500℃, and the photoeatalytie H2 production efficiency from a methanol solution is much higher than that from a triethanolamine solution. It can be ascribed to the oxidization of methanol also contributes to the H2 production during the photochemical reaction process. Moreover, the photocatalytic mechanism for the H2 production from the present ZnO suspension system containing methanol solution is also discussed in detail.
文摘Fibres from a variety of sources are a common constituent of pig feeds. They provide a means to utilise locallyproduced plant materials which are often a by-product of the food or drink industry. The value of a high fibre diet in terms of producing satiety has long been recognised. However the addition of fibre can reduce feed intake, which is clearly detrimental during stages of the production cycle when nutrient needs are high, for example in growing piglets and during lactation. More recently, fibre has been found to promote novel benefits to pig production systems,particularly given the reduction in antimicrobial use world-wide, concern for the welfare of animals fed a restricted diet and the need to ensure that such systems are more environmentally friendly. For example, inclusion of dietary fibre can alter the gut microbiota in ways that could reduce the need for antibiotics, while controlled addition of certain fibre types may reduce nitrogen losses into the environment and so reduce the environmental cost of pig production.Of particular potential value is the opportunity to use crude fibre concentrates as ’functional’ feed additives to improve young pig growth and welfare. Perhaps the greatest opportunity for the use of high fibre diets is to improve the reproductive efficiency of pigs. Increased dietary fibre before mating improves oocyte maturation, prenatal survival and litter size; providing a consumer-acceptable means of increasing the amount of saleable meat produced per sow. The mechanisms responsible for these beneficial effects remain to be elucidated. However, changes in plasma and follicular fluid concentrations of key hormones and metabolites, as well as effects of the hypothalamic satiety centre on gonadotrophin secretion and epigenetic effects are strong candidates.
基金supported by the National Natural Science Foundation of China(Nos.11675226 and 11722546)the Major State Basic Research Development Program of China(Nos.2014CB845405 and 2015CB856903)
文摘Recent progress of the quantum molecular dynamics model for describing the dynamics of heavy-ion collisions is viewed, in particular the nuclear fragmentation, isospin physics, particle production and in-medium effect, hadron-induced nuclear reactions, hypernucleus, etc.The neck fragmentation in Fermi-energy heavy-ion collisions is investigated for extracting the symmetry energy at subsaturation densities. The isospin effects, in-medium properties, and the behavior of high-density symmetry energy in medium-and high-energy heavy-ion collisions are thoroughly discussed. The hypernuclide dynamics formed in heavy-ion collisions and in hadron-induced reactions is analyzed and addressed in the future experiments at the high-intensity heavy-ion accelerator facility(HIAF).
基金This work was supported by the Research Foundation of China University of Petroleum-Beijing at Karamay(No.XQZX20200010)the Natural Science Foundation of Xinjiang Uygur Autonomous Region(No.2019D01B57)+3 种基金the University Scientific Research Project of Xinjiang Uygur Autonomous Region(No.XJEDU2019Y067)the Xinjiang Uygur Autonomous Region Innovation Environment Construction Project(No.2019Q025)the Sichuan Province Regional Innovation Cooperation Project(No.2020YFQ0036)the CNPC Strategic Cooperation Science and Technology Project(ZLZX2020-01-04-04)。
文摘Temporary plugging agent(TPA)is widely used in many fields of petroleum reservoir drilling and production,such as temporary plugging while drilling and petroleum well stimulation by diverting in acidizing or fracturing operations.The commonly used TPA mainly includes hard particles,fibers,gels,and composite systems.However,current particles have many limitations in applications,such as insufficient plugging strength and slow degradation rate.In this paper,a degradable pre-formed particle gel(DPPG)was developed.Experimental results show that the DPPG has an excellent static swelling effect and self-degradation performance.With a decrease in the concentration of total monomers or cross-linker,the swelling volume of the synthesized DPPG gradually increases.However,the entire self-degradation time gradually decreases.The increase in 2-acrylamide-2-methylpropanesulfonic acid(AMPS)in the DPPG composition can significantly increase its swelling ratio and shorten the self-degradation time.Moreover,DPPG has excellent high-temperature resistance(150°C)and high-salinity resistance(200,000 mg/L NaCl).Core displacement results show that the DPPG has a perfect plugging effect in the porous media(the plugging pressure gradient was as high as 21.12 MPa),and the damage to the formation after degradation is incredibly minor.Therefore,the DPPG can be used as an up-and-coming TPA in oil fields.
基金support was partially provided by the University of Connecticut Research Foundation,Storrs Agricultural Experiment Station,Chinese Academy of Sciences Outstanding Overseas Chinese Scholars Award,and the National Natural Science Foundation of China(40671071).
文摘The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were employed to characterize the temporal trends and spatial patterns in farm production and five pertinent inputs of cultivated cropland, irrigation ratio, agricultural labor, machinery power and chemical fertilizer. Stochastic frontier production function was applied to quantify the dependence of the farm production on these inputs. The growth of farm production was decomposed to reflect the contributions by input growths and change in total factor productivity.. The change in total factor productivity was further decomposed into the changes in technology and in technical efficiency. The gross value of farm production in the region of study increased by 1.6 fold during 1980-1999. Among the five selected farm inputs, machinery power and chemical fertilizer increased by 1.8 and 2.8 fold, respectively. The increases in cultivated cropland, irrigated cropland, and agricultural labor were all less than 0.16 fold. The growth in the farm production was primarily contributed by the increase in the total factor productivity during 1980-1985, and by input growths after 1985. More than 80% of the contributions by input growths were attributed to the increased application of fertilizer and machinery. In the change of total factor productivity, the technology change dominated over the technical efficiency change in the study period except in the period of 1985-1990, implying that institution and investment played important roles in farm production growth. There was a decreasing trend in the technical efficiency in the region of study, indicating a potential to increase farm production by improving the technical efficiency in farm activities. Given the limited natural resources in the basin, the results of this study suggested that, for a sustainable growth of farm production in the area, efforts should be directed to technology progress and improvement in technical efficiency in the use of available resources.
基金supported by the National Natural Science Foundation of China(No.11875328).
文摘The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both economic and environmental terms.The cross-section data were obtained from the TALYS Evaluated Nuclear Data Library(TENDL).A thick target model was used to study the consumption of the target isotopes in the transmutation process.The transmutation yield was calculated using the highest beam intensity available with the China initiative accelerator-driven system.It was found that the light nuclide-induced spallation reaction can significantly reduce the radio toxicity of the investigated long-lived fission products.Using the transmutation target made of elemental LLFP and the proton beam with an intensity of 5 mA,the consumption of 90 Sr,93 Zr,107 Pd,or 137 Cs can reach approximately 500 g per year.
基金Supported by the National Natural Science Foundation of China(11061012)Project Supported by Program to Sponsor Teams for Innovation in the Construction of Talent Highlands in Guangxi Institutions of Higher Learning([2011]47)the Guangxi Natural Science Foundation of China(2012GXNSFAA053010)
文摘Consider a sequence of i.i.d.positive random variables.An universal result in almost sure limit theorem for products of sums of partial sums is established.We will show that the almost sure limit theorem holds under a fairly general condition on the weight dk= k-1 exp(lnβk),0≤β〈1.And in a sense,our results have reached the optimal form.
基金supported by the Major State Basic Research Development Program in China(No.2014CB845400)the National Natural Science Foundation of China(No.11375184)+2 种基金the Youth Innovation Promotion Association Fund of CAS(No.CX2030040079)the Ministry of Science and Technology(Mo ST)of China(No.2016YFE0104800)the Science and Technological Fund of Anhui Province for Outstanding Youth(No.1808085J02)
文摘We report the multiplicity dependence of charged particle production for the n~±, K~±, p, , and ? mesons at |y|<1:0 in p + p collisions at s^(1/2) = 200 GeV from a PYTHIA simulation. The impact of multiple parton interactions and gluon contributions is studied and found to be a possible source of the splitting of the particle yields as a function of p_T with respect to the multiplicity. No obvious particle species dependence of the splitting is observed.The multiplicity dependence of the ratios Kˉ/πˉ, K^+/π^+,/πˉ, p/π^+, and K_s^0 at mid-rapidity in p+ p collisions is found to follow a tendency similar to that in Au t Au collisions at (s_(NN))^(1/2) = 200 GeV at the Relativistic Heavy Ion Collider, indicating similar underlying initial production mechanisms despite the differences in the initial colliding systems.
文摘To investigate the characteristics of hydrogen production by a novel fermentative hydrogen-producing bacterial strain B49 (AF481148 in EMBL), batch experiments are conducted under different conditions. Hydrogen production has a correlation with cell growth and the consumption of glucose and soluble protein. The optimum pH for cell growth is 4.5±0.15. At acidic pH 4.0±0.15, the bacteria has the maximum accumulated hydrogen volume of 2382 ml/L culture and the maximum hydrogen evolution rate of 339.9 ml/L culture·h with 1% glucose. The optimum temperature for cell growth and hydrogen production is 35℃. In addition, fermentative hydrogen-producing bacterial strain B49 can generate hydrogen from the decomposition of other organic substrates such as wheat, soybean, corn, and potato. Moreover, it can also produce hydrogen from molasses wastewater and brewage wastewater, and hydrogen yields are 137.9 ml H 2/g COD and 49.9 ml H 2/g COD, respectively.
基金supported by the Laoshan Laboratory(No.LSKJ LSKJ202203506)the Taishan Scholars Program,and the National Natural Science Foundation of China(Grant No.41976074).
文摘Sand production is one of the main obstacles restricting gas extraction efficiency and safety from marine natural gas hydrate(NGH)reservoirs.Particle migration within the NGH reservoir dominates sand production behaviors,while their relationships were rarely reported,severely constrains quantitative evaluation of sand production risks.This paper reports the optical observations of solid particle migration and production from micrometer to mesoscopic scales conditioned to gravel packing during depressurization-induced NGH dissociation for the first time.Theoretical evolutionary modes of sand migration are established based on experimental observations,and its implications on field NGH are comprehensively discussed.Five particle migration regimes of local borehole failure,continuous collapse,wormhole expansion,extensive slow deformation,and pore-wall fluidization are proved to occur during depressurization.The types of particle migration regimes and their transmission modes during depressurization are predominantly determined by initial hydrate saturation.In contrast,the depressurization mainly dominates the transmission rate of the particle migration regimes.Furthermore,both the cumulative mass and the medium grain size of the produced sand decrease linearly with increasing initial methane hydrate(MH)saturation.Discontinuous gas bubble emission,expansion,and explosion during MH dissociation delay sand migration into the wellbore.At the same time,continuous water flow is a requirement for sand production during hydrate dissociation by depressurization.The experiments enlighten us that a constitutive model that can illustrate visible particle migration regimes and their transmission modes is urgently needed to bridge numerical simulation and field applications.Optimizing wellbore layout positions or special reservoir treatment shall be important for mitigating sand production tendency during NGH exploitation.
基金Supported by Major Science and Technology Program of Hainan Province(ZDKJ2016017-01,ZDKJ2016017-03)
文摘[Objective] The paper to investigate the effects of pelleted total mixed ration of different particle size on production performance and serum biochemical index of fattening Hainan black goats.[Method] Thirty-six fattening Hainan black goats with the same genetic backgrounds and similar initial weight of(19.02±0.22) kg were randomly divided into three treatments. Goats were fed with Juncao+concentrate(control group), pel-leted total mixed ration I(particle size 6 mm, experimental group I) and II(particle size 5 mm, experimental group II), respectively. The trial lasted 45 d.[Result](1) The final weight and daily gain of experimental group II were significantly higher than those of control group( P<0.05), and the daily gain of experimental group II was also higher than that of experimental group I(P<0.05);the feed intake of experimental group II was markedly higher than that of control group(P<0.05), but was significantly lower than that of experimental group I(P<0.05). The feed/gain ratio of experimental group II was significantly lower than those of control group and experimental group I(P<0.05).(2) The feed gain cost of experimental group II was markedly lower than that of control group(P<0.05), but the gross profit was significantly higher than those of control group and experimental group I(P<0.05).(3) Compared with the control group, the serum total protein content of experimental group II increased markedly( P<0.05) while the urea nitrogen level decreased(P>0.05).[Conclusion] The pelleted total mixed ration with the particle size of 5 mm obtained better fattening ef-fect, and obviously improved the serum total protein level.
基金financial support from the National Natural Science Foundation of China (NSFC-21776251, 21625604, 21671172 and 91934302)。
文摘Electrochemical ozone production(EOP) via water electrolysis represents an attractive method for the generation of high-purity O3. Herein, the X-PtZn/Zn-N-C electrocatalysts show a strong structural sensitive behavior depends on the size of the PtZn nanoparticles and their EOP activity exhibits a volcano-type dependence for the O3 performance in neutral media. The 7.7-PtZn/Zn-N-C exhibits EOP current efficiency of 4.2%, and shows the prominent performance in the production of gaseous O3 with a value of 1647 ppb at 30 min, which is almost 4-fold compared to 2.2-Pt Zn/Zn-N-C. Based on the experiments and theoretical calculations, the performance of the EOP process was determined by the nanoparticle size-effect and the synergistic effect between the PtZn nanoparticles and atomically dispersed Zn-N-C. Furthermore, the fivemembered cyclic structure of O3 can be stabilized between the PtZn nanoparticle and the Zn-N-C support,indicating that O3 is produced at the interface.
文摘Respecting the on-time-delivery (OTD) for manufacturing orders is mandatory. This depends, however, on the probability distribution of incoming order rate. The case of non-equal distribution, such as aggregated arrivals, may compromise the observance of on-time supplies for some orders. The purpose of this paper is to evaluate the conditions of post-optimality for stochastic order rate governed production systems in order to observe OTD. Instead of a heuristic or a simulative exploration, a Cartesian-based approach is applied to developing the necessary and sufficient mathematical condition to solve the problem statement. The research result demonstrates that increasing </span><span style="font-family:Verdana;">speed of throughput reveals a latent capacity, which allows arrival orders </span><span style="font-family:Verdana;">above capacity limits to be backlog-buffered and rescheduled for OTD, exploiting the virtual manufacturing elasticity inherent to all production systems to increase OTD reliability of non JIT-based production systems.
基金supported by The National Key Research and Development Program of China(No.2020YFB1708200).
文摘Design change is an inevitable part of the product development process.This study proposes an improved binary multi‐objective PSO algorithm guided by problem char-acteristics(P‐BMOPSO)to solve the optimisation problem of complex product change plan considering service performance.Firstly,a complex product multi‐layer network with service performance is established for the first time to reveal the impact of change effect propagation on the product service performance.Secondly,the concept of service performance impact(SPI)is defined by decoupling the impact of strongly associated nodes on the service performance in the process of change affect propagation.Then,a triple‐objective selection model of change nodes is established,which includes the three indicators:SPI degree,change cost,and change time.Furthermore,an integer multi‐objective particle swarm optimisation algorithm guided by problem characteristics is developed to solve the model above.Experimental results on the design change problem of a certain type of Skyworth TV verify the effectiveness of the established optimisation model and the proposed P‐BMOPSO algorithm.
基金The National Natural Science Foundation of China under contract No.41721005the COMRA Program of China under contract No.DY135-E2-2-03the Polar Environment Comprehensive Investigation&Assessment Program of China under contract Nos CHINARE2017-01-04-03 and CHINARE2017-04-01-06
文摘During the 29 th Chinese National Antarctic Research Expedition,spatial variations in nitrogen isotopic composition of particulate nitrogen(δ15NPN)and their controlling factors were examined in detail with regard to nitrate drawdown by phytoplankton and particulate nitrogen(PN)remineralization in the Prydz Bay and its adjacent areas.To better constrain the nitrogen transformations,the physical and chemical parameters,including temperature,salinity,nutrients,PN andδ15NPN in seawater column were measured from surface to bottom.In addition,the nitrogen isotopic fractionation factor of nitrate assimilation by phytoplankton in the mixed layer,and the nitrogen isotopic fractionation factor of PN remineralization below the mixed layer were estimated using Rayleigh model and Steady State model,respectively.Our results showed that suspended particles had its lowestδ15NPN in the surface layer,which was due to the preferential assimilation of 14 N in nitrate by phytoplankton.Theδ15NPN in the mixed layer of the Prydz Bay and its adjacent areas decreased from the inner shelf to the outer basin,ascribing to the effect of isotope fractionation during phytoplankton assimilation.In mixed layer,the spatial distribution ofδ15NPN associated with particulate organic matter(POM)production can be well interpreted according to Rayleigh model and Steady State model.The nitrogen isotope fractionation factor during phytoplankton assimilating nitrate was estimated as 10.0‰by Steady State model,which was more reasonable than that calculated by Rayleigh model.These results validate the previous reports of fractionation factor during nitrate assimilation by phytoplankton.Increasingδ15NPN with depth below the euphotic zone correlated with the decreasing PN contents,and it was attributed to preferential remineralization of 14 N in PN by bacteria.In subsurface and deep layer,theδ15NPN distributions also conformed to Rayleigh model and Steady State model during PN remineralization,with a fractionation factor of about 3.6‰and 3.2‰,respectively.It is the first time to estimate the fractionation factor during POM production and remineralization in the Prydz Bay and its adjacent areas.Such fractionation may provide a useful tool for the follow-up study of the nitrogen dynamics in the Southern Ocean.
基金the founding support from the National Natural Science Foundation of China(21906072 and 22006057)the Natural Science Foundation of Jiangsu Province(BK20190982)+1 种基金“Doctor of Mass entrepreneurship and innovation”Project in Jiangsu ProvinceDoctoral Scientific Research Foundation of Jiangsu University of Science and Technology(China)(1062931806 and 1142931803)。
文摘Photocatalytic water splitting for hydrogen production(H_(2))is one of the main potential applications of photocatalytic technology,which can use solar energy as the energy required for chemical reactions to alleviate the energy crisis.In this work,zero-dimensional/two-dimensional(0D/2D)contact surface CdS/α-Fe_(2)O_(3)(CF)heterojunction photocatalyst was synthesized via a simple solvothermal method.Photocatalytic hydrogen production experiments revealed that the CF-15 sample shows the optimal photocatalytic H_(2)rate(1806μmol·h^(-1)·g^(-1))and apparent quantum efficiency(AQE=13.7%atλ=420 nm).The enhancement of photocatalytic performance is mainly attributed to the contact of 0D/2D interface and the synergistic effect of Z-scheme electron transfer mechanism.This work provides an effective way for modified composite semiconductor photocatalyst by constructing special interface heterojunction to achieve highly efficiently catalysis.
基金Supported by Project of Guiyang Branch Company,Guizhou Tobacco Company(ZYK[2015]2)~~
文摘Objective] This study was conducted to discuss growth characteristics and partial production and quality characters of different varieties, so as to provide can-didates for tobacco production as wel as a theoretical basis for variety deployment in Guizhou. [Method] ‘K326’ was used as control, the experiment for variance analysis of growth characteristics and partial production and quality characters of dif-ferent tobacco varieties was carried out in Fengsan Town, Kaiyang County, Guizhou Province in 2015. [Result] GY8 grew faster in early stages and slower in late stages, the growth periods of GY2 (130 d) and GY5(129 d) were the longest, while those of Yun85 (121 d) and Yun87 (121 d) were the shortest; and GY2, GY5 and GY8 had larger plant heights, maximum leaf widths and maximum leaf areas, and Yun85, Yun87 and K326 showed larger stem girths and maximum leaf lengths. Yun87 exhibited lower natural incidences of diseases, while Yun85 and GY8 showed higher incidences of diseases. GY2, GY5 and GY8 had higher nicotine, total nitro-gen, K and Cl contents, while Yun85, Yun87 and K326 had higher total sugar and reducing sugar contents and higher total sugar/nicotine ratio. Yun85 and Yun87 showed better economic characters, while GY5 and GY8 showed poorer economic characters. [Conclusion] Yun85 and Yun87 have quality characters better than GY2 and GY8, field natural incidences of diseases lower than GY2 and GY8, and better economic characters, and thus could serve as candidates in future flue-cured tobac-co production in Guizhou.