The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicoti...The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.展开更多
The fracturing of the pressure compartments in sedimentary basins may not be caused completely by natural hydraulic fracturing. On the bases of fracture mechanics and numerical simulation, we consider that there are t...The fracturing of the pressure compartments in sedimentary basins may not be caused completely by natural hydraulic fracturing. On the bases of fracture mechanics and numerical simulation, we consider that there are two mechanisms concerning the fracturing of pressure compartments, which are as follows: (1) natural hydraulic fracturing of the sediments within pressure compartments, and (2) tensile fracturing due to tangential traction. When the fracture, formed in the sediments within pressure compartments due to hydraulic fracturing, arrives at the base of the seal, the intensely tangential tensile stresses are created and lead to the fracturing of the seal. After the seal fractured, the fluid escaped from the pressure compartments. In a shallow pressure compartment, the duration of fracture opening and fluid expulsion is about 10-20 years in a cycle.展开更多
Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to...Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis.展开更多
The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related dea...The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related death. As the infected fraction cannot be eliminated from the population, this kind of model has only the unique endemic equilibrium that is globally asymptotically stable. Under the special case where the new members of immigration are all susceptible, the model considered here shows a threshold phenomenon and a sharp threshold has been obtained. In order to prove the global asymptotical stability of the endemic equilibrium, the authors introduce the change of variable, which can reduce our four-dimensional system to a three-dimensional asymptotical autonomous system with limit equation.展开更多
Green manure–crop rotation is a sustainable approach to protect crops against diseases and improve yield.However,the mechanism by which green manuring manipulates the crop-associated microbial community remains to be...Green manure–crop rotation is a sustainable approach to protect crops against diseases and improve yield.However,the mechanism by which green manuring manipulates the crop-associated microbial community remains to be elucidated.In this study,we explored the horizontal processes of bacterial communities in different compartments of the soil–root interface(bulk soil,rhizosphere soil,rhizoplane and endosphere)of tobacco by performing a field experiment including four rotation practices,namely,tobacco rotated with smooth vetch,ryegrass,radish,and winter fallow(without green manure).Results showed that the co-occurrence networks constructed by adjacent compartments of the soil–root interface with green manuring had more edges than without green manuring,indicating dramatic microbial interactions.Green manuring increased the dispersal-niche continuum index between bulk soil and other compartments,indicating that it facilitated the horizontal dispersal of microbes.For the different green manuring practices,the neutral community model explained 24.6–27.6%of detection frequency for bacteria,and at least one compartment under each practice had a normalized stochasticity ratio higher than the 50%boundary point,suggesting that the deterministic and stochastic processes jointly shaped the tobacco microbiome.In conclusion,green manuring generally facilitates bacterial community dispersal across different compartments and enhances potential interactions among adjacent compartments.This study provides empirical evidence for understanding the microbiome assembly under green manure–crop rotation.展开更多
Striated muscle tissue contains fibers with high oxidative capacity (heart muscle), higher oxidative capacity (type I and IIA fibers of skeletal muscle) and low oxidative capacity (type IIB/X fibers of skeletal muscle...Striated muscle tissue contains fibers with high oxidative capacity (heart muscle), higher oxidative capacity (type I and IIA fibers of skeletal muscle) and low oxidative capacity (type IIB/X fibers of skeletal muscle). Muscle fibers with higher oxidative capacity contain large mitochondria tightly packed with cristae as well as small forms of mitochondria containing relatively few cristae. The intensive development of the mitochondrial apparatus in the post-activity period reflects the adaptive processes, which is intended to supply the increased energy requirements of muscle fibers with higher oxidative capacity. Muscle fibers with low oxidative capacity contain significantly less mitochondria than fibers with higher capacity. It is typical to type IIB fibers that after intensive muscle activity there are damaged myofibrils in a relatively small area, some myofibrils are twisted and lose the connection with the neighboring structures. It is still not fully known how skeletal muscles with different oxidative capacity respond to an increased functional activity and what differences exist in these fibers between oxidative capacity and function of myofibrils. The aim of the present short review was to compare structural-functional changes in mitochondrial and myofibrillar compartments of heart and skeletal muscle fibers with different oxidative capacity and the effect of increased functional activity on the interaction of these compartments.展开更多
The structure of an air-floating caisson is suitable for the major structure of caisson-type artificial islands.Thus,it has been rapidly developed and widely used in the exploration and development of oil and gas fiel...The structure of an air-floating caisson is suitable for the major structure of caisson-type artificial islands.Thus,it has been rapidly developed and widely used in the exploration and development of oil and gas fields in shallow sea and intertidal zones.Air-floating transportation technology is one of the key technologies employed in this structure.In this paper,the factors influencing the dynamic response characteristics of air-floating caisson with multi-compartments(AFCMC)were studied using model tests.The length and the height of each air-floating structure in the model were 1.0 and 0.1 m,respectively.In addition,the 1:100 models with 6,8,and 10 compartments under regular waves were tested in the wave flume,respectively.In the experiments,the respective water depths were set at 0.2,0.3,and 0.4 m,and the corresponding drafts were 0.05,0.06,and 0.07 m.Results show that with the increase of draft,the heave natural period increased and the maximum amplitude of the heave motion decreased.Meanwhile,the pitch motion decreased at 6 and 8 compartments and increased at 10 compartments.As the water depth increased,the maximum amplitude and amplitude change of heave and pitch motions first increased and then decreased.However,several amplitudes close to the maximum amplitude appeared in the measured period at shallower water depth,thereby indicating the vertical movements of the structure enhanced under shallow water.The increase in the number of compartments reduced the vertical movements under 6.0 m draft,but it increased the vertical movements under 5.0 and 7.0 m draft.Thus,increasing the number of compartments has a limited capacity to improve the motion performance of the structure.展开更多
The spatial organization of the genome plays an important role in the regulation of gene expression. How- ever, the core structural features of animal genomes, such as topologically associated domains (TADs) and chr...The spatial organization of the genome plays an important role in the regulation of gene expression. How- ever, the core structural features of animal genomes, such as topologically associated domains (TADs) and chromatin loops, are not prominent in the extremely compact Arabidopsis genome. In this study, we examine the chromatin architecture, as well as their DNA methylation, histone modifications, accessible chromatin, and gene expression, of maize, tomato, sorghum, foxtail millet, and rice with genome sizes ranging from 0.4 to 2.4 Gb. We found that these plant genomes can be divided into mammalian-like A/B compartments. At higher resolution, the chromosomes of these plants can be further partitioned to local AJB compartments that reflect their euchromatin, heterochromatin, and polycomb status. Chromatins in all these plants are organized into domains that are not conserved across species. They show similarity to the Drosophila compartment domains, and are clustered into active, polycomb, repressive, and interme- diate types based on their transcriptional activities and epigenetic signatures, with domain border overlaps with the local A/B compartment junctions. In the large maize and tomato genomes, we observed extensive chromatin loops. However, unlike the mammalian chromatin loops that are enriched at the TAD border, plant chromatin loops are often formed between gene islands outside the repressive domains and are closely associated with active compartments. Our study indicates that plants have complex and unique 3D chromatin architectures, which require further study to elucidate their biological functions.展开更多
The implementation of early and accurate detection of aircraft cargo compartment fire is of great significance to ensure flight safety.The current airborne fire detection technology mostly relies on single-parameter s...The implementation of early and accurate detection of aircraft cargo compartment fire is of great significance to ensure flight safety.The current airborne fire detection technology mostly relies on single-parameter smoke detection using infrared light.This often results in a high false alarm rate in complex air transportation envi-ronments.The traditional deep learning model struggles to effectively address the issue of long-term dependency in multivariate fire information.This paper proposes a multi-technology collaborative fire detection method based on an improved transformers model.Dual-wavelength optical sensors,flue gas analyzers,and other equipment are used to carry out multi-technology collaborative detection methods and characterize various feature dimensions of fire to improve detection accuracy.The improved Transformer model which integrates the self-attention mechanism and position encoding mechanism is applied to the problem of long-time series modeling of fire information from a global perspective,which effectively solves the problem of gradient disappearance and gradient explosion in traditional RNN(recurrent neural network)and CNN(convolutional neural network).Two different multi-head self-attention mechanisms are used to classify and model multivariate fire information,respectively,which solves the problem of confusing time series modeling and classification modeling in dealing with multivariate classification tasks by a single attention mechanism.Finally,the output results of the two models are fused through the gate mechanism.The research results show that,compared with the traditional single-feature detection technology,the multi-technology collaborative fire detection method can better capture fire information.Compared with the traditional deep learning model,the multivariate fire pre-diction model constructed by the improved Transformer can better detect fires,and the accuracy rate is 0.995.展开更多
Contagious pathogens like COVID-19 transmitted via respiratory droplets spread effortlessly in the passenger compartments of transport,significantly jeopardizing passengers’safety when taking public transportation.To...Contagious pathogens like COVID-19 transmitted via respiratory droplets spread effortlessly in the passenger compartments of transport,significantly jeopardizing passengers’safety when taking public transportation.To date,studies on the fundamental theories of airborne droplet transmission and the engineering application of decontamination techniques are insufficient for the prevention and control of pathogens transmitting in the compartments of passenger transport.It is essential to systematically investigate the control approaches to restrain pathogens from transmitting in passenger compartments.Herein,a theoretical framework for calculating the transmission of pathogens in a complex compartment environment was proposed,and experimental platforms that satisfy the Biosafety Level-2 Laboratory safety level for compartment environment simulations were built based on a set of real train cabins.On these bases,numerical investigations on the motion of pathogen-laden droplets were conducted,and decontamination techniques were examined experimentally.Thereby,control measures on the pathogen transmission and pathogen decontamination schemes were proposed.Moreover,highly efficient decontamination devices were developed,and coping strategies for epidemic emergencies were devised.The outcomes provide theoretical and technical support for developing the next generation of transportation and the prevention and control measures cooperatively considering regular and pandemic times.展开更多
Prevacuolar compartments (PVCs) and endosomal compartments are membrane-bound organelles mediating protein traffic to vacuoles in the secretory and endocytic pathways of plant cells. Over the years, great progress h...Prevacuolar compartments (PVCs) and endosomal compartments are membrane-bound organelles mediating protein traffic to vacuoles in the secretory and endocytic pathways of plant cells. Over the years, great progress has been made towards our understanding in these two compartments in plant cells. In this review, we will summarize our contributions toward the identification and characterization of plant prevacuolar and endosomal compartments. Our studies will serve as important steps in future molecular characterization of PVC biogenesis and PVC-mediated protein traffickinq in plant cells.展开更多
In the nucleus, chromatin is folded into hierarchical architecture that is tightly linked to various nuclear functions. However, the underlying molecular mechanisms that confer these architectures remain incompletely ...In the nucleus, chromatin is folded into hierarchical architecture that is tightly linked to various nuclear functions. However, the underlying molecular mechanisms that confer these architectures remain incompletely understood. Here, we investigated the functional roles of H3 lysine 9 dimethylation(H3 K9 me2), one of the abundant histone modifications, in three-dimensional(3 D)genome organization. Unlike in mouse embryonic stem cells, inhibition of methyltransferases G9 a and GLP in differentiated cells eliminated H3 K9 me2 predominantly at A-type(active) genomic compartments, and the level of residual H3 K9 me2 modifications was strongly associated with B-type(inactive) genomic compartments. Furthermore, chemical inhibition of G9 a/GLP in mouse hepatocytes led to decreased chromatin-nuclear lamina interactions mainly at G9 a/GLP-sensitive regions, increased degree of genomic compartmentalization, and up-regulation of hundreds of genes that were associated with alterations of the 3 D chromatin. Collectively, our data demonstrated essential roles of H3 K9 me2 in 3 D genome organization.展开更多
This study investigates the wet towing characteristics of an integrated wellhead platform supported by a bucket foundation.These characteristics are crucial for optimizing offshore construction efficiency and enabling...This study investigates the wet towing characteristics of an integrated wellhead platform supported by a bucket foundation.These characteristics are crucial for optimizing offshore construction efficiency and enabling the development of small marginal oil fields.The wet towing behavior of the integrated wellhead platform was explored through a combination of physical experiments and numerical simulations.Physical experiments were conducted to validate the accuracy of the numerical simulations.Subsequently,numerical simulations were employed to determine the impacts of towing speed and wave direction on the towing process of the integrated wellhead platform.Finally,the impact of compartment failure due to bulkhead damage on towage stability was analyzed.Findings indicate that the wave and towing directions influence the motion of the platform at various degrees of freedom.The platform demonstrates optimal stability when towing against waves,particularly when the towing direction aligns at a specific angle relative to the wave direction.In addition,a controlled increase in towing speed within a specific range effectively mitigates roll and pitch motions,which enhances the overall tow stability of the platform.Notably,compartment failure has an adverse effect on the towing stability,particularly in aft compartments.Therefore,it requires careful consideration and attention in practical engineering scenarios.展开更多
The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personn...The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personnel from firing artillery within the cab.To investigate the overpressure characteristics of the FFICC,a foreign trade equipment model was used as the research object,and a numerical model was established to analyze the propagation of muzzle blast from the muzzle to the interior of the crew compartment under extreme firing condition.For comparative verification,the muzzle blast experiment included overpressure data from both the flow field outside the crew compartment(FFOCC)and the FFICC,as well as the acceleration data of the crew compartment structure(Str-CC).The research findings demonstrate that the overpressure-time curves of the FFICC exhibit multi-peak characteristics,while the pressure wave shows no significant discontinuity.The enclosed nature of the cab hinders the dissipation of pressure wave energy within the FFICC,leading to sustained high-amplitude overpressure.The frameskin structure helps attenuate the impact of muzzle blast on the FFICC.Conversely,local high overpressure caused by the convex or concave features of the cab's exterior significantly amplifies the overpressure amplitude within the FFICC.展开更多
Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone...Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone fractures,crush injuries,and burns.[1,2]While rare,ACoS can also occur in atraumatic settings following periods of prolonged limb compression,such as intoxication.[3]Atraumatic ACoS is easily overlooked,resulting in diagnostic delay and poor patient outcomes.Prompt recognition and surgical management is essential to prevent critical sequelae.展开更多
BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by ...BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by an increase in intra-abdo-minal pressure with physiological disturbance can be caused by severe massive fecal impaction.CASE SUMMARY A 33-year-old female presented to the emergency room with massive abdominal distension that rapidly progressed to abdominal compartment syndrome.The pa-tient was diagnosed with hypoganglionosis.Life-saving emergent proctoco-lectomy was performed to save the patient.CONCLUSION Abdominal compartment syndrome can develop secondary to excessive colonic distension.This extreme but rare situation must be addressed immediately.Hypo-ganglionosis is a potential cause of severe constipation that may present in adu-lthood.展开更多
Crush syndrome demands an integrated multidisciplinary approach that spans acute surgical decisions and long-term functional recovery.In response to Khan et al’s recent systematic review,we propose complementary pers...Crush syndrome demands an integrated multidisciplinary approach that spans acute surgical decisions and long-term functional recovery.In response to Khan et al’s recent systematic review,we propose complementary perspectives that address two underrepresented dimensions:Vascular surgical decision-making and psychiatric rehabilitation.We emphasize the use of intraoperative technologies such as indocyanine green fluorescence angiography and compartment pressure monitoring to guide limb salvage strategies and reperfusion management.Additionally,we advocate for the systematic integration of mental health screening and trauma-informed psychiatric care to address the high prevalence of psychological distress in survivors.Embedding these domains into standardized protocols could enhance both short-and long-term outcomes,particularly in highimpact trauma and disaster settings.展开更多
The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematic...The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematical model as well as three-dimensional computational fluid dynamics (CFD) model was established to analyze the flow regions of feedwells on an industrial scale. The concept of RTD, although a well-known method for the characterization of mixing behavior in conventional mixers and reactors, is still a novel measure for the characterization of mixing in feedwells. Numerical simulation results show that the inlet feed rate and the aspect ratio of feedwells are the most critical parameters which affect the RTD of feedwell. Further simulation experiments were then carried out. Under the optimal operation conditions, the volume fraction of dead zone can reduce by10.8% and an increasement of mixing flow volume fraction by 6.5% is also observed. There is an optimum feed inlet rate depending on the feedwell design. The CFD model in conjunction with the RTD analysis then can be used as an effective tool in the design, evaluation and optimization of thickener feedwell in the red mud separation.展开更多
Background:A growing body of evidence has revealed that the mammalian genome is organized into hierarchical layers that are closely correlated with and may even be causally linked with variations in gene expression.Re...Background:A growing body of evidence has revealed that the mammalian genome is organized into hierarchical layers that are closely correlated with and may even be causally linked with variations in gene expression.Recent studies have characterized chromatin organization in various porcine tissues and cell types and compared them among species and during the early development of pigs.However,how chromatin organization differs among pig breeds is poorly understood.Results:In this study,we investigated the 3D genome organization and performed transcriptome characterization of two adipose depots(upper layer of backfat[ULB]and greater omentum[GOM])in wild boars and Bama pigs;the latter is a typical indigenous pig in China.We found that over 95%of the A/B compartments and topologically associating domains(TADs)are stable between wild boars and Bama pigs.In contrast,more than 70%of promoterenhancer interactions(PEIs)are dynamic and widespread,involving over a thousand genes.Alterations in chromatin structure are associated with changes in the expression of genes that are involved in widespread biological functions such as basic cellular functions,endocrine function,energy metabolism and the immune response.Approximately 95%and 97%of the genes associated with reorganized A/B compartments and PEIs in the two pig breeds differed between GOM and ULB,respectively.Conclusions:We reported 3D genome organization in adipose depots from different pig breeds.In a comparison of Bama pigs and wild boar,large-scale compartments and TADs were mostly conserved,while fine-scale PEIs were extensively reorganized.The chromatin architecture in these two pig breeds was reorganized in an adipose depotspecific manner.These results contribute to determining the regulatory mechanism of phenotypic differences between Bama pigs and wild boar.展开更多
Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective tr...Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and possibility of tissue sampling error. Similar to delayed contrast enhancement, equilibrium contrast enhanced MRI/MDCT and T1 mapping is completely noninvasive and may play a specialized role in diagnosis of subclinical and other myocardial pathologies. DE-MRI and when T1-mapping demonstrated sub-epicardium, sub-endocardial and patchy mid-myocardial enhancement in myocarditis, Behcet's disease and sarcoidosis, respectively. Furthermore, recent studies showed that the combined technique of cine, T2-weighted and DE-MRI technique has high diagnostic accuracy for detecting myocarditis. When the tomographic techniques are coupled with myocardial perfusion and left ventricular function they can provide valuable information on the progression of myocardial pathologies and effectiveness of new therapies.展开更多
文摘The gene encoded for tryptophan decarboxylase (TDC), which is the key enzyme in terpenoil indole alkaloids pathway, was targeted to different subcellular compartments and stably expressed in transgenic tobacco (Nicotiana tabacum L.) plants at the levels detected by Western blot and tryptamine accumulation analysis. It was shown that the TDC was located in subcellular compartments, the chloroplasts and cytosol. The recombinant TDC targeted to chloroplasts and cytosol in tobacco plants was effectively expressed as soluble protein by Western blot analysis and enzymatic assay. The level of tryptamine accumulation in chloroplast was higher than that in cytosol and very low in vacuole and endoplasmic reticulum (ER) to be hardly detected by Western blot analysis. It was indicated that the highest amount of tryptamine was in chloroplasts, lower in endoplasmic reticula and the lowest in vacuoles as compared to those in wild type plants. The TDC targeted to different subcellular compartments of tobacco plants and its expression level were studied by different nucleotide sequences coding signal peptides at 5'-end of tdc gene in order to know the effects of the TDC in compartmentation on its functionality.
文摘The fracturing of the pressure compartments in sedimentary basins may not be caused completely by natural hydraulic fracturing. On the bases of fracture mechanics and numerical simulation, we consider that there are two mechanisms concerning the fracturing of pressure compartments, which are as follows: (1) natural hydraulic fracturing of the sediments within pressure compartments, and (2) tensile fracturing due to tangential traction. When the fracture, formed in the sediments within pressure compartments due to hydraulic fracturing, arrives at the base of the seal, the intensely tangential tensile stresses are created and lead to the fracturing of the seal. After the seal fractured, the fluid escaped from the pressure compartments. In a shallow pressure compartment, the duration of fracture opening and fluid expulsion is about 10-20 years in a cycle.
文摘Strictosidine synthase (STR) is a key enzyme involved in the biosynthesis of terpenoid indole alkaloids (TIA) by condensing tryptamine and secologanin into strictosidine. The transgenic tobacco plants targeting STR to subcellular compartments were established to express STR in chloroplast, vacuole and endoplasmic reticulum (ER) by the tobacco stable transformation. It was shown that STR was effectively expressed in the above subcellular compartments by Western blot analysis and STR enzymatic assay. In vitro , STR enzymatic assay was measured indirectly by fluorimetrically detecting depletion of tryptamine feeding on secologanin in the reaction mixture. The tryptamine were completely depleted by STR in the crude extract of leaves of transgenic tobacco plants targeting and expressing STR in the chloroplast, vacuole and ER, which ascertained the STR functionally targeted to the three subcellular compartments. To confirm STR correct targeting and expressing in chloroplast, the chloroplasts were isolated and the fractions of purified chloroplasts were analyzed by Western blot. The hypothesis of STR correct targeting to the chloroplast was tested. The results have implications on our understanding of the complex intracellular trafficking in metabolic intermediates of TIA biosynthesis.
基金This research is supported by the NNSF of China (19971066)
文摘The SEIR epidemic model studied here includes constant inflows of new susceptibles, exposeds, infectives, and recovereds. This model also incorporates a population size dependent contact rate and a disease-related death. As the infected fraction cannot be eliminated from the population, this kind of model has only the unique endemic equilibrium that is globally asymptotically stable. Under the special case where the new members of immigration are all susceptible, the model considered here shows a threshold phenomenon and a sharp threshold has been obtained. In order to prove the global asymptotical stability of the endemic equilibrium, the authors introduce the change of variable, which can reduce our four-dimensional system to a three-dimensional asymptotical autonomous system with limit equation.
基金supported financially by the National Key Research and Development Program of China(2021YFD1700200)the China Agriculture Research System of MOF and MARA(CARS-22).
文摘Green manure–crop rotation is a sustainable approach to protect crops against diseases and improve yield.However,the mechanism by which green manuring manipulates the crop-associated microbial community remains to be elucidated.In this study,we explored the horizontal processes of bacterial communities in different compartments of the soil–root interface(bulk soil,rhizosphere soil,rhizoplane and endosphere)of tobacco by performing a field experiment including four rotation practices,namely,tobacco rotated with smooth vetch,ryegrass,radish,and winter fallow(without green manure).Results showed that the co-occurrence networks constructed by adjacent compartments of the soil–root interface with green manuring had more edges than without green manuring,indicating dramatic microbial interactions.Green manuring increased the dispersal-niche continuum index between bulk soil and other compartments,indicating that it facilitated the horizontal dispersal of microbes.For the different green manuring practices,the neutral community model explained 24.6–27.6%of detection frequency for bacteria,and at least one compartment under each practice had a normalized stochasticity ratio higher than the 50%boundary point,suggesting that the deterministic and stochastic processes jointly shaped the tobacco microbiome.In conclusion,green manuring generally facilitates bacterial community dispersal across different compartments and enhances potential interactions among adjacent compartments.This study provides empirical evidence for understanding the microbiome assembly under green manure–crop rotation.
文摘Striated muscle tissue contains fibers with high oxidative capacity (heart muscle), higher oxidative capacity (type I and IIA fibers of skeletal muscle) and low oxidative capacity (type IIB/X fibers of skeletal muscle). Muscle fibers with higher oxidative capacity contain large mitochondria tightly packed with cristae as well as small forms of mitochondria containing relatively few cristae. The intensive development of the mitochondrial apparatus in the post-activity period reflects the adaptive processes, which is intended to supply the increased energy requirements of muscle fibers with higher oxidative capacity. Muscle fibers with low oxidative capacity contain significantly less mitochondria than fibers with higher capacity. It is typical to type IIB fibers that after intensive muscle activity there are damaged myofibrils in a relatively small area, some myofibrils are twisted and lose the connection with the neighboring structures. It is still not fully known how skeletal muscles with different oxidative capacity respond to an increased functional activity and what differences exist in these fibers between oxidative capacity and function of myofibrils. The aim of the present short review was to compare structural-functional changes in mitochondrial and myofibrillar compartments of heart and skeletal muscle fibers with different oxidative capacity and the effect of increased functional activity on the interaction of these compartments.
基金support pro-vided by the National Science Foundation of China(No.52171274)the National Key Research and Development Project(No.2018YFC0810402)+2 种基金the Chongqing Elite In-novation and Entrepreneurship Demonstration Team(No.CQYC201903204)the Chongqing Special Post-doctoral Science Foundation(No.XM2019)the State Key Laboratory of Hydraulic Engineering Simulation and Safety(Tianjin University)(No.HESS-12).
文摘The structure of an air-floating caisson is suitable for the major structure of caisson-type artificial islands.Thus,it has been rapidly developed and widely used in the exploration and development of oil and gas fields in shallow sea and intertidal zones.Air-floating transportation technology is one of the key technologies employed in this structure.In this paper,the factors influencing the dynamic response characteristics of air-floating caisson with multi-compartments(AFCMC)were studied using model tests.The length and the height of each air-floating structure in the model were 1.0 and 0.1 m,respectively.In addition,the 1:100 models with 6,8,and 10 compartments under regular waves were tested in the wave flume,respectively.In the experiments,the respective water depths were set at 0.2,0.3,and 0.4 m,and the corresponding drafts were 0.05,0.06,and 0.07 m.Results show that with the increase of draft,the heave natural period increased and the maximum amplitude of the heave motion decreased.Meanwhile,the pitch motion decreased at 6 and 8 compartments and increased at 10 compartments.As the water depth increased,the maximum amplitude and amplitude change of heave and pitch motions first increased and then decreased.However,several amplitudes close to the maximum amplitude appeared in the measured period at shallower water depth,thereby indicating the vertical movements of the structure enhanced under shallow water.The increase in the number of compartments reduced the vertical movements under 6.0 m draft,but it increased the vertical movements under 5.0 and 7.0 m draft.Thus,increasing the number of compartments has a limited capacity to improve the motion performance of the structure.
文摘The spatial organization of the genome plays an important role in the regulation of gene expression. How- ever, the core structural features of animal genomes, such as topologically associated domains (TADs) and chromatin loops, are not prominent in the extremely compact Arabidopsis genome. In this study, we examine the chromatin architecture, as well as their DNA methylation, histone modifications, accessible chromatin, and gene expression, of maize, tomato, sorghum, foxtail millet, and rice with genome sizes ranging from 0.4 to 2.4 Gb. We found that these plant genomes can be divided into mammalian-like A/B compartments. At higher resolution, the chromosomes of these plants can be further partitioned to local AJB compartments that reflect their euchromatin, heterochromatin, and polycomb status. Chromatins in all these plants are organized into domains that are not conserved across species. They show similarity to the Drosophila compartment domains, and are clustered into active, polycomb, repressive, and interme- diate types based on their transcriptional activities and epigenetic signatures, with domain border overlaps with the local A/B compartment junctions. In the large maize and tomato genomes, we observed extensive chromatin loops. However, unlike the mammalian chromatin loops that are enriched at the TAD border, plant chromatin loops are often formed between gene islands outside the repressive domains and are closely associated with active compartments. Our study indicates that plants have complex and unique 3D chromatin architectures, which require further study to elucidate their biological functions.
基金This work was funded by the National Science Foundation of China(Grant No.U2033206)the Project of Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province(Grant No.MZ2022KF05,Grant No.MZ2022JB01)+3 种基金the project of Key Laboratory of Civil Aviation Emergency Science&Technology,CAAC(Grant No.NJ2022022,Grant No.NJ2023025)the project of Postgraduate Project of Civil Aviation Flight University of China(Grant No X2023-1)the project of the undergraduate innovation and entrepreneurship training program(Grant No 202210624024)the project of General Programs of the Civil Aviation Flight University of China(Grant No J2020-072).
文摘The implementation of early and accurate detection of aircraft cargo compartment fire is of great significance to ensure flight safety.The current airborne fire detection technology mostly relies on single-parameter smoke detection using infrared light.This often results in a high false alarm rate in complex air transportation envi-ronments.The traditional deep learning model struggles to effectively address the issue of long-term dependency in multivariate fire information.This paper proposes a multi-technology collaborative fire detection method based on an improved transformers model.Dual-wavelength optical sensors,flue gas analyzers,and other equipment are used to carry out multi-technology collaborative detection methods and characterize various feature dimensions of fire to improve detection accuracy.The improved Transformer model which integrates the self-attention mechanism and position encoding mechanism is applied to the problem of long-time series modeling of fire information from a global perspective,which effectively solves the problem of gradient disappearance and gradient explosion in traditional RNN(recurrent neural network)and CNN(convolutional neural network).Two different multi-head self-attention mechanisms are used to classify and model multivariate fire information,respectively,which solves the problem of confusing time series modeling and classification modeling in dealing with multivariate classification tasks by a single attention mechanism.Finally,the output results of the two models are fused through the gate mechanism.The research results show that,compared with the traditional single-feature detection technology,the multi-technology collaborative fire detection method can better capture fire information.Compared with the traditional deep learning model,the multivariate fire pre-diction model constructed by the improved Transformer can better detect fires,and the accuracy rate is 0.995.
基金This work is supported by the consulting research project of the major project of China National Railway Group Co.,Ltd.(No.K2020J003)the Chinese Academy of Engineering(No.2020-XY-79)。
文摘Contagious pathogens like COVID-19 transmitted via respiratory droplets spread effortlessly in the passenger compartments of transport,significantly jeopardizing passengers’safety when taking public transportation.To date,studies on the fundamental theories of airborne droplet transmission and the engineering application of decontamination techniques are insufficient for the prevention and control of pathogens transmitting in the compartments of passenger transport.It is essential to systematically investigate the control approaches to restrain pathogens from transmitting in passenger compartments.Herein,a theoretical framework for calculating the transmission of pathogens in a complex compartment environment was proposed,and experimental platforms that satisfy the Biosafety Level-2 Laboratory safety level for compartment environment simulations were built based on a set of real train cabins.On these bases,numerical investigations on the motion of pathogen-laden droplets were conducted,and decontamination techniques were examined experimentally.Thereby,control measures on the pathogen transmission and pathogen decontamination schemes were proposed.Moreover,highly efficient decontamination devices were developed,and coping strategies for epidemic emergencies were devised.The outcomes provide theoretical and technical support for developing the next generation of transportation and the prevention and control measures cooperatively considering regular and pandemic times.
基金Supported by grants from the Research Grants Council of Hong Kong(CUHK4156/01M,CUHK4260/02M,CUHK4307/03M,and CUHK4580/05M)National Science Foundation of China (30529001)+1 种基金CUHK Scheme C,UGCAoE(B-07/99)Germany/HK Joint Research Scheme to L.Jiang.
文摘Prevacuolar compartments (PVCs) and endosomal compartments are membrane-bound organelles mediating protein traffic to vacuoles in the secretory and endocytic pathways of plant cells. Over the years, great progress has been made towards our understanding in these two compartments in plant cells. In this review, we will summarize our contributions toward the identification and characterization of plant prevacuolar and endosomal compartments. Our studies will serve as important steps in future molecular characterization of PVC biogenesis and PVC-mediated protein traffickinq in plant cells.
基金supported by the National Key R&D Program of China(Grant No.2018YFC1003500 awarded to BW)the National Natural Science Foundation of China(Grant No.31771435 awarded to BW)
文摘In the nucleus, chromatin is folded into hierarchical architecture that is tightly linked to various nuclear functions. However, the underlying molecular mechanisms that confer these architectures remain incompletely understood. Here, we investigated the functional roles of H3 lysine 9 dimethylation(H3 K9 me2), one of the abundant histone modifications, in three-dimensional(3 D)genome organization. Unlike in mouse embryonic stem cells, inhibition of methyltransferases G9 a and GLP in differentiated cells eliminated H3 K9 me2 predominantly at A-type(active) genomic compartments, and the level of residual H3 K9 me2 modifications was strongly associated with B-type(inactive) genomic compartments. Furthermore, chemical inhibition of G9 a/GLP in mouse hepatocytes led to decreased chromatin-nuclear lamina interactions mainly at G9 a/GLP-sensitive regions, increased degree of genomic compartmentalization, and up-regulation of hundreds of genes that were associated with alterations of the 3 D chromatin. Collectively, our data demonstrated essential roles of H3 K9 me2 in 3 D genome organization.
基金the National Natural Science Foundation of China(No.52271287).
文摘This study investigates the wet towing characteristics of an integrated wellhead platform supported by a bucket foundation.These characteristics are crucial for optimizing offshore construction efficiency and enabling the development of small marginal oil fields.The wet towing behavior of the integrated wellhead platform was explored through a combination of physical experiments and numerical simulations.Physical experiments were conducted to validate the accuracy of the numerical simulations.Subsequently,numerical simulations were employed to determine the impacts of towing speed and wave direction on the towing process of the integrated wellhead platform.Finally,the impact of compartment failure due to bulkhead damage on towage stability was analyzed.Findings indicate that the wave and towing directions influence the motion of the platform at various degrees of freedom.The platform demonstrates optimal stability when towing against waves,particularly when the towing direction aligns at a specific angle relative to the wave direction.In addition,a controlled increase in towing speed within a specific range effectively mitigates roll and pitch motions,which enhances the overall tow stability of the platform.Notably,compartment failure has an adverse effect on the towing stability,particularly in aft compartments.Therefore,it requires careful consideration and attention in practical engineering scenarios.
基金supported by the National Natural Science Foundation of China(Grant No.U2341269)。
文摘The muzzle blast overpressure induces disturbances in the flow field inside the crew compartment(FFICC)of a truck-mounted howitzer during the artillery firing.This overpressure is the primary factor preventing personnel from firing artillery within the cab.To investigate the overpressure characteristics of the FFICC,a foreign trade equipment model was used as the research object,and a numerical model was established to analyze the propagation of muzzle blast from the muzzle to the interior of the crew compartment under extreme firing condition.For comparative verification,the muzzle blast experiment included overpressure data from both the flow field outside the crew compartment(FFOCC)and the FFICC,as well as the acceleration data of the crew compartment structure(Str-CC).The research findings demonstrate that the overpressure-time curves of the FFICC exhibit multi-peak characteristics,while the pressure wave shows no significant discontinuity.The enclosed nature of the cab hinders the dissipation of pressure wave energy within the FFICC,leading to sustained high-amplitude overpressure.The frameskin structure helps attenuate the impact of muzzle blast on the FFICC.Conversely,local high overpressure caused by the convex or concave features of the cab's exterior significantly amplifies the overpressure amplitude within the FFICC.
文摘Acute compartment syndrome(ACoS)involves a complex pathological process in which rising pressures within an enclosed muscle space ultimately result in anoxia and cell death.The most common etiologies include long bone fractures,crush injuries,and burns.[1,2]While rare,ACoS can also occur in atraumatic settings following periods of prolonged limb compression,such as intoxication.[3]Atraumatic ACoS is easily overlooked,resulting in diagnostic delay and poor patient outcomes.Prompt recognition and surgical management is essential to prevent critical sequelae.
文摘BACKGROUND Hypoganglionosis is a rare gastrointestinal acquired motility disorder that res-embles Hirschsprung’s disease and can manifest in the adult life.Abdominal compartment syndrome,a condition characterized by an increase in intra-abdo-minal pressure with physiological disturbance can be caused by severe massive fecal impaction.CASE SUMMARY A 33-year-old female presented to the emergency room with massive abdominal distension that rapidly progressed to abdominal compartment syndrome.The pa-tient was diagnosed with hypoganglionosis.Life-saving emergent proctoco-lectomy was performed to save the patient.CONCLUSION Abdominal compartment syndrome can develop secondary to excessive colonic distension.This extreme but rare situation must be addressed immediately.Hypo-ganglionosis is a potential cause of severe constipation that may present in adu-lthood.
文摘Crush syndrome demands an integrated multidisciplinary approach that spans acute surgical decisions and long-term functional recovery.In response to Khan et al’s recent systematic review,we propose complementary perspectives that address two underrepresented dimensions:Vascular surgical decision-making and psychiatric rehabilitation.We emphasize the use of intraoperative technologies such as indocyanine green fluorescence angiography and compartment pressure monitoring to guide limb salvage strategies and reperfusion management.Additionally,we advocate for the systematic integration of mental health screening and trauma-informed psychiatric care to address the high prevalence of psychological distress in survivors.Embedding these domains into standardized protocols could enhance both short-and long-term outcomes,particularly in highimpact trauma and disaster settings.
基金Project (50876116) supported by the National Natural Science Foundation of China
文摘The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematical model as well as three-dimensional computational fluid dynamics (CFD) model was established to analyze the flow regions of feedwells on an industrial scale. The concept of RTD, although a well-known method for the characterization of mixing behavior in conventional mixers and reactors, is still a novel measure for the characterization of mixing in feedwells. Numerical simulation results show that the inlet feed rate and the aspect ratio of feedwells are the most critical parameters which affect the RTD of feedwell. Further simulation experiments were then carried out. Under the optimal operation conditions, the volume fraction of dead zone can reduce by10.8% and an increasement of mixing flow volume fraction by 6.5% is also observed. There is an optimum feed inlet rate depending on the feedwell design. The CFD model in conjunction with the RTD analysis then can be used as an effective tool in the design, evaluation and optimization of thickener feedwell in the red mud separation.
基金supported by grants from the National Key R&D Program of China(2020YFA0509500)the National Natural Science Foundation of China(U19A2036,31772576,31530073 and 31802044)+1 种基金the Sichuan Science and Technology Program(2021YFYZ0009 and 2021YFYZ0030)the International Cooperation Project of Science and Technology Department of Sichuan Province(2021YFH0033).
文摘Background:A growing body of evidence has revealed that the mammalian genome is organized into hierarchical layers that are closely correlated with and may even be causally linked with variations in gene expression.Recent studies have characterized chromatin organization in various porcine tissues and cell types and compared them among species and during the early development of pigs.However,how chromatin organization differs among pig breeds is poorly understood.Results:In this study,we investigated the 3D genome organization and performed transcriptome characterization of two adipose depots(upper layer of backfat[ULB]and greater omentum[GOM])in wild boars and Bama pigs;the latter is a typical indigenous pig in China.We found that over 95%of the A/B compartments and topologically associating domains(TADs)are stable between wild boars and Bama pigs.In contrast,more than 70%of promoterenhancer interactions(PEIs)are dynamic and widespread,involving over a thousand genes.Alterations in chromatin structure are associated with changes in the expression of genes that are involved in widespread biological functions such as basic cellular functions,endocrine function,energy metabolism and the immune response.Approximately 95%and 97%of the genes associated with reorganized A/B compartments and PEIs in the two pig breeds differed between GOM and ULB,respectively.Conclusions:We reported 3D genome organization in adipose depots from different pig breeds.In a comparison of Bama pigs and wild boar,large-scale compartments and TADs were mostly conserved,while fine-scale PEIs were extensively reorganized.The chromatin architecture in these two pig breeds was reorganized in an adipose depotspecific manner.These results contribute to determining the regulatory mechanism of phenotypic differences between Bama pigs and wild boar.
文摘Myocardial pathologies are major causes of morbidity and mortality worldwide. Early detection of loss of cellular integrity and expansion in extracellular volume(ECV) in myocardium is critical to initiate effective treatment. The three compartments in healthy myocardium are: intravascular(approximately 10% of tissue volume), interstitium(approximately 15%) and intracellular(approximately 75%). Myocardial cells, fibroblasts and vascular endothelial/smooth muscle cells represent intracellular compartment and the main proteins in the interstitium are types Ⅰ/Ⅲ collagens. Microscopic studies have shown that expansion of ECV is an important feature of diffuse physiologic fibrosis(e.g., aging and obesity) and pathologic fibrosis [heart failure, aortic valve disease, hypertrophic cardiomyopathy, myocarditis, dilated cardiomyopathy, amyloidosis, congenital heart disease, aortic stenosis, restrictive cardiomyopathy(hypereosinophilic and idiopathic types), arrythmogenic right ventricular dysplasia and hypertension]. This review addresses recent advances in measuring of ECV in ischemic and non-ischemic myocardial pathologies. Magnetic resonance imaging(MRI) has the ability to characterize tissue proton relaxation times(T1, T2, and T2*). Proton relaxation times reflect the physical and chemical environments of water protons in myocardium. Delayed contrast enhanced-MRI(DE-MRI) and multi-detector computed tomography(DE-MDCT) demonstrated hyper-enhanced infarct, hypo-enhanced microvascular obstruction zone and moderately enhanced peri-infarct zone, but are limited for visualizing diffuse fibrosis and patchy microinfarct despite the increase in ECV. ECV can be measured on equilibrium contrast enhanced MRI/MDCT and MRI longitudinal relaxation time mapping. Equilibrium contrast enhanced MRI/MDCT and MRI T1 mapping is currently used, but at a lower scale, as an alternative to invasive sub-endomyocardial biopsies to eliminate the need for anesthesia, coronary catheterization and possibility of tissue sampling error. Similar to delayed contrast enhancement, equilibrium contrast enhanced MRI/MDCT and T1 mapping is completely noninvasive and may play a specialized role in diagnosis of subclinical and other myocardial pathologies. DE-MRI and when T1-mapping demonstrated sub-epicardium, sub-endocardial and patchy mid-myocardial enhancement in myocarditis, Behcet's disease and sarcoidosis, respectively. Furthermore, recent studies showed that the combined technique of cine, T2-weighted and DE-MRI technique has high diagnostic accuracy for detecting myocarditis. When the tomographic techniques are coupled with myocardial perfusion and left ventricular function they can provide valuable information on the progression of myocardial pathologies and effectiveness of new therapies.