The purpose of this paper is to study the theory of conservative estimating functions in nonlinear regression model with aggregated data. In this model, a quasi-score function with aggregated data is defined. When thi...The purpose of this paper is to study the theory of conservative estimating functions in nonlinear regression model with aggregated data. In this model, a quasi-score function with aggregated data is defined. When this function happens to be conservative, it is projection of the true score function onto a class of estimation functions. By constructing, the potential function for the projected score with aggregated data is obtained, which have some properties of log-likelihood function.展开更多
The concept of aggregated signal is introduced. Quantitatively, an aggregated signal can be defined as the scalar signal: it accumulates in its own variations only those spectral components that are presented simultan...The concept of aggregated signal is introduced. Quantitatively, an aggregated signal can be defined as the scalar signal: it accumulates in its own variations only those spectral components that are presented simultaneously in each scalar time series of the multidimensional signal to be analyzed. Moreover, an algorithm of aggregation is proposed to suppress the spectral components that are present in any of the scalar components but absent in others (these components can be called local disturbance signals, for instance of technogenic nature). The main purpose of constructing the aggregated signal is to make clearer the common tendency of low-frequency data-flow in geophysical networks, which indicates an increase in collective behavior.It is known that almost all models of the process of earthquake preparation have pointed out an increase in collective behavior of components of geophysical fields in the region of preparation when the coming geocatastrophe has entered its long- and mid-term stages.展开更多
The structural parameters of the aggregated state of polyamide (PA)-1010 annealed at various temperatures were computed by means of the desmearing intensity from Smalt Angle X-ray Scattering (SAXS) measurements and by...The structural parameters of the aggregated state of polyamide (PA)-1010 annealed at various temperatures were computed by means of the desmearing intensity from Smalt Angle X-ray Scattering (SAXS) measurements and by using the concept of the distance distribution function. The results indicated that the structural parameters of the aggregated state were strongly dependent upon heat treatment conditions and the maximum values of the structural parameters were obtained for the samples annealed at T = 175 degrees C. The particle size Z annealed at different temperature was ranged between 8.1-12.8nm, and the values of the distance distribution function P-max(Z) were obtained when Z = 4.0-6.8 nm. Using one dimension electron density correlation function (1D EDCF) method long period (L) and thickness of the lamellar (d(0)) were estimated and were found to increase with the increase of the degree of crystallinity.展开更多
Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuat...Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuations during cluster formation.Although these structures may have very different degrees of aggregation,a quantitative method is lacking to describe them,and how these structures evolve remains unclear.Therefore a significant step towards precise control of particle self-assembly is to describe and analyze various aggregation structures during cluster formation quantitatively.In this work,we are motivated to propose a method to directly count and quantitatively compare different aggregated structures.We also present several case studies to evaluate how the aggregated structures during cluster formation are affected by external controlling factors,e.g.,different interaction ranges,interaction strengths,or anisotropy of attraction.展开更多
The alpha stable self-similar stochastic process has been proved an effective model for high variable data traffic. A deep insight into some special issues and considerations on use of the process to model aggregated ...The alpha stable self-similar stochastic process has been proved an effective model for high variable data traffic. A deep insight into some special issues and considerations on use of the process to model aggregated VBR video traffic is made. Different methods to estimate stability parameter a and self-similar parameter H are compared. Processes to generate the linear fractional stable noise (LFSN) and the alpha stable random variables are provided. Model construction and the quantitative comparisons with fractional Brown motion (FBM) and real traffic are also examined. Open problems and future directions are also given with thoughtful discussions.展开更多
Resonance Raman spectra of aggregated meso-tetra(4-pyridinium)porphyrin diacid (H8TPyP^6+) were studied with excitation near the exciton absorption bands of 470 nm. The UV-Vis absorption and resonance light scatt...Resonance Raman spectra of aggregated meso-tetra(4-pyridinium)porphyrin diacid (H8TPyP^6+) were studied with excitation near the exciton absorption bands of 470 nm. The UV-Vis absorption and resonance light scattering spectra of HsTPyP^6+ monomers and aggregates were also measured. The observed Raman bands of monomeric and aggregated HsTPyP^6+ were assigned on the basis of the observed deuteration shifts and by comparing with the Raman spectra of analogous porphyrin diacids. Aggregation causes moderate downshifts (2-6 cm^-1) for high-frequency modes involving the in-plane CC/CN stretches of the porphyrin core and a dramatic upshift (12 cm^-1) for the out-of-plane saddling mode of the porphyrin ring. The structural changes induced by aggregation and the possible hydrogen bonding interaction between the HsTPyP^6+ molecules in the aggregate are discussed based on the spectral observations.展开更多
Aggregation is used to represent the real world in a model at an appropriate level of abstraction.We used the convection-diffusion equation to examine the implications of aggregation progressing from a three-dimension...Aggregation is used to represent the real world in a model at an appropriate level of abstraction.We used the convection-diffusion equation to examine the implications of aggregation progressing from a three-dimensional(3D)spatial description to a model representing a system as a single box that exchanges sediment with the adjacent environment.We highlight how all models depend on some forms of parametric closure,which need to be chosen to suit the scale of aggregation adopted in the model.All such models are therefore aggregated and make use of some empirical relationships to deal with sub-scale processes.One such appropriately aggregated model,the model for the aggregated scale morphological interaction between tidal basin and adjacent coast(ASMITA),is examined in more detail and used to illustrate the insight that this level of aggregation can bring to a problem by considering how tidal inlets and estuaries are impacted by sea level rise.展开更多
[KG(0.01mm]This study focuses on the community structure of aggregated bacteria in Lake Baikal and relationships with free-living bacteria. Fluorescent in situ hybridization (FISH) methods were used in samples of bact...[KG(0.01mm]This study focuses on the community structure of aggregated bacteria in Lake Baikal and relationships with free-living bacteria. Fluorescent in situ hybridization (FISH) methods were used in samples of bacteria taken in April, 2001. Bacterial counts of free-living bacteria by DAPI staining ranged from 0.2×10 6 to 3.2×10 6 cells·mL -1, decreasing with depth, whereas aggregated bacterial numbers dramatically increased with depth, ranging from 0.4×10 4 to 3.3×10 4 cells·mL -1. Ratios of EUB probe binding cells to DAPI counts ranged from 52.3 to 74.1% in free-living bacteria and from 39.6 to 66.7% in aggregated bacteria, respectively. Community composition of aggregated bacteria was very different from free-living bacteria, especially at 25m depth where highest phytoplankton numbers were observed. The vertical profile of aggregated bacteria community was very characteristic. Beta-Proteobacteria increased with depth down to 100m. At 250m, gamma-Proteobacteria was 44% of DAPI bound cells, while other groups were less than 1%. We conclude that community structures of free-living and aggregated bacteria were different, and they may sustain the ecosystem in independent ways.展开更多
NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of servic...NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of services(QoS).In order to improve throughput and minimum latency,aMultivariate Renkonen Regressive Weighted Preference Bootstrap Aggregation based Nonorthogonal Multiple Access(MRRWPBA-NOMA)technique is introduced for network communication.In the downlink transmission,each mobile device’s resources and their characteristics like energy,bandwidth,and trust are measured.Followed by,the Weighted Preference Bootstrap Aggregation is applied to recognize the resource-efficient mobile devices for aware data transmission by constructing the different weak hypotheses i.e.,Multivariate Renkonen Regression functions.Based on the classification,resource and trust-aware devices are selected for transmission.Simulation of the proposed MRRWPBA-NOMA technique and existing methods are carried out with different metrics such as data delivery ratio,throughput,latency,packet loss rate,and energy efficiency,signaling overhead.The simulation results assessment indicates that the proposed MRRWPBA-NOMA outperforms well than the conventional methods.展开更多
In this paper, component carrier selection and beamforming on carrier aggregated channels in Heterogeneous Networks are proposed. The scheme jointly selects the component carrier and precoding (i.e. beamforming) vecto...In this paper, component carrier selection and beamforming on carrier aggregated channels in Heterogeneous Networks are proposed. The scheme jointly selects the component carrier and precoding (i.e. beamforming) vectors with the cooperation of the other cells to deal with the interference between Macro cell and Pico cell. The component carrier selection and beamforming is achieved by optimizing the multi-cell downlink throughput. This optimization results in shutting down a subset of the component carrier in order to allow for a perfect interference removal at the receive side in the dense low power node deployment scenario. Additionally, algorithm based on Branch and Bound Method is used to reduce the search complexity of the algorithm. Simulation results show that the proposed scheme can achieve high cell-average and cell-edge throughput for the Pico cell in the Heterogeneous Networks.展开更多
Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate ...Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate the contribution of conservation farming technology or reduced tillage in potato-based rotations in the Colombian Andes in order to rehabilitate total and aggregated soil organic C in disturbed organic matter-rich Andisols. Soils were sampled from farms with 7-year of reduced tillage and farms with conventional farming practices. Ultrasound energy was applied to samples to disrupt aggregation and total soil C was determined in order to investigate the amount of carbon held inside the aggregates of different soil size classes. Results indicated that reduced tillage in potato-based crop rotations increased the soil C concentration and average C content in the whole profile (≈117 cm depth) by 50 and 33% (1636 t C ha?1 vs. 1224 t C ha?1), respectively, as compared to conventional farming practices. Carbon content increased 177% in the subsoil (A2 horizon, 78 -117 cm depth, from 215 to 596 t?ha?1), although most of the soil C was in the A1 horizon (between 0 -78 cm average thickness, 1097 t?ha?1). These increases show that reduced tillage enhances C stores in Andisols which are already high in organic matter. In addition, C in aggregates represented more than 80% of the total organic matter and it was positively affected by conservation practices. The C increase was preferential in the smaller macroaggregates (展开更多
Cognitive Radio (CR) is a promising technology to increase the efficiency of spectrum by opportunistic access. However, in many cases the sensed spectrum is so broken that it cannot be utilized sufficiently with tradi...Cognitive Radio (CR) is a promising technology to increase the efficiency of spectrum by opportunistic access. However, in many cases the sensed spectrum is so broken that it cannot be utilized sufficiently with traditional continuous spectrum allocation strategy. Spectrum aggregation can make full use of narrow spectrum fragments while the overhead it brings may reduce the overall performance of the system. This paper proposes a Mixed Contiguous and Aggregated Spectrum Allocation (MixCASA) algorithm for CR based TD-LTE Networks. This algorithm combines contiguous with discontiguous spectrum allocation together in order to guarantee the feasibility and efficiency of system. Simulation results show that the MixCASA algorithm can increase the number of allocated channels, and reduce the overhead brought by excessive spectrum aggregation as well.展开更多
Donor–acceptor(D-A)conjugated polymers have demonstrated great potential in organicfield-effect transistors application,and their aggregated structure is a crucial factor for high charge mobility.However,the aggregate...Donor–acceptor(D-A)conjugated polymers have demonstrated great potential in organicfield-effect transistors application,and their aggregated structure is a crucial factor for high charge mobility.However,the aggregated structure of D-A conjugated polymerfilms is complex and the structure–property relationship is difficult to understand.This review provides an overview of recent progress in controlling the aggregated structure of D-A conjugated polymerfilms for higher mobility,including the mechanisms,methods,and properties.Wefirst discuss the multilevel microstructures of D-A conjugated polymerfilms,and then summarize the current understanding of the relationship betweenfilm microstructures and charge transport properties.Subsequently,we review the theory of D-A conjugated polymer crystallization.After that,we summarize the common methods to control the aggregated structure of semi-crystalline and near-amorphous D-A conjugated polymerfilms,such as crystallites and aggregates,tie chains,film alignment,and attempt to understand them from the basic theory of polymer crystallization.Finally,we provide the current challenges in controlling the aggregated structure of D-A conjugated polymerfilms and in understanding the structure–property relationship.展开更多
Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables....Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables.A number of researchers have studied DEA and RA and noted the positive and negative differences between them.Aggregated ratio analysis(ARA) model,which provide an important linkage between DEA and RA theory,is equivalent to the CCR DEA model,and this equivalence property offers a great deal of opportunities for DEA to be interpreted and applied in different ways.This paper extends the results of ARA model and proposes an extended aggregated ratio analysis(EARA) model,similar as the development from CCR model to BCC model in DEA context.The proposed model can offer an insight into the characteristic of returns to scale,playing the corresponding role as BCC model does.The numerical example is revisited in the paper and the results are compared.展开更多
Aggregation of metal nanoparticles plays an important role in surface enhanced Raman scattering (SERS). Here, a strategy of dynamically aggregating/releasing gold nanopartides is demonstrated using a gold-nanofilm-c...Aggregation of metal nanoparticles plays an important role in surface enhanced Raman scattering (SERS). Here, a strategy of dynamically aggregating/releasing gold nanopartides is demonstrated using a gold-nanofilm-coated nanofiber, with the assistance of enhanced optical force and plasmonic photothermal effect. Strong SERS signals of rhodamine 6G are achieved at the hotspots formed in the inter-particle and film-partide nanogaps. The proposed SERS substrate was demonstrated to have a sensitivity of 10-12 M, reliable reproducibility, and good stability.展开更多
π-Conjugated organic/polymer materials-based solar cells have attracted tremendous research interest in the fields of chemistry,physics,materials science,and energy science.To date,the best-performance polymer solar ...π-Conjugated organic/polymer materials-based solar cells have attracted tremendous research interest in the fields of chemistry,physics,materials science,and energy science.To date,the best-performance polymer solar cells(PSCs)have achieved power conversion efficiencies exceeding 18%,mostly driven by the molecular design and device structure optimization of the photovoltaic materials.This review article provides a comprehensive overview of the key advances and current status in aggregated structure research of PSCs.Here,we start by providing a brief tutorial on the aggregated structure of photovoltaic polymers.The characteristic parameters at different length scales and the associated characterization techniques are overviewed.Subsequently,a variety of effective strategies to control the aggregated structure of photovoltaic polymers are discussed for polymer:fullerene solar cells and polymer:nonfullerene small molecule solar cells.Particularly,the control strategies for achieving record efficiencies in each type of PSCs are highlighted.More importantly,the in-depth structure-performance relationships are demonstrated with selected examples.Finally,future challenges and research prospects on understanding and optimizing the aggregated structure of photovoltaic polymers and their blends are provided.展开更多
With the increasing use of renewable resources and electric vehicles(EVs), the variability and uncertainty in their nature put forward a high requirement for flexibility in AC distribution system incorporating voltage...With the increasing use of renewable resources and electric vehicles(EVs), the variability and uncertainty in their nature put forward a high requirement for flexibility in AC distribution system incorporating voltage source converter(VSC) based multi-terminal direct current(MTDC) grids. In order to improve the capability of distribution systems to cope with uncertainty, the flexibility enhancement of AC-MTDC distribution systems considering aggregated EVs is studied. Firstly, the charging and discharging model of one EV is proposed considering the users' demand difference and traveling needs. Based on this, a vehicle-to-grid(V2G) control strategy for aggregated EVs to participate in the flexibility promotion of distribution systems is provided. After that, an optimal flexible dispatching method is proposed to improve the flexibility of power systems through cooperation of VSCs, controllable distributed generations(CDGs), aggregated EVs, and energy storage systems(ESSs). Finally, a case study of an AC-MTDC distribution system is carried out. Simulation results show that the proposed dispatching method is capable of effectively enhancing the system flexibility, reducing renewable power curtailment, decreasing load abandonment, and cutting down system cost.展开更多
This paper addresses the transportation network design problem (NDP) wherein the dis- tance limit and en-route recharge of electric vehicles are taken into account. Specifically, in this work, the network design pro...This paper addresses the transportation network design problem (NDP) wherein the dis- tance limit and en-route recharge of electric vehicles are taken into account. Specifically, in this work, the network design problem aims to select the optimal planning policy from a set of infrastructure design scenarios considering both road expansions and charging station allocations under a specified construction budget. The user-equilibrium mixed-vehicular traffic assignment problem with en-route recharge (MVTAP-ER) is formulated into a novel convex optimization model and extended to a newly developed bi-level program of the aggregated NDP integrating recharge facility allocation (NDP-RFA). In the algorithmic framework, a convex optimization technique and a tailored CA are adopted for, respectively, solving the subproblem MVTAP-ER and the primal problem NDP-RFA. Systematic ex- periments are conducted to test the efficacy of the proposed approaches. The results highlight the impacts of distance limits and budget levels on the project selection and evaluation, and the benefits of considering both road improvement policy and recharge service provision as compared to accounting for the latter only. The results also report that the two design objectives, to respectively minimize the total system travel time and vehicle miles travelled, are conflicting for certain scenarios.展开更多
Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and m...Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and metabolic events,which need to be carried out at the right place,time,and intensity.Such mechanisms include axonal transport,local synthesis,and liquid-liquid phase separations.Alterations and malfunctions in these processes are correlated to neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS).展开更多
The misfolding and subsequent aggregation of proteins into amyloid fibrils underlie the onset of a variety of human disorders collectively known as amyloidosis.Transthyretin(TTR)is one of the>30 amyloidogenic prote...The misfolding and subsequent aggregation of proteins into amyloid fibrils underlie the onset of a variety of human disorders collectively known as amyloidosis.Transthyretin(TTR)is one of the>30 amyloidogenic proteins identified to date and is associated with a group of highly debilitating and life-threatening disorders called TTR amyloidosis(ATTR).ATTR comprises senile systemic amyloidosis,which is linked to wild-type(WT)TTR aggregation,and hereditary ATTR,a dominantly inherited disorder caused by the deposition of one of over 130 TTR genetic variants.Senile systemic amyloidosis is a prevalent age-related amyloidosis,affecting up to 25%of the population over 80 years of age,and is characterized by the build-up of TTR fibrils in the myocardium.Regarding hereditary ATTR,the clinical presentation is highly heterogeneous,primarily affecting the peripheral nervous system(familial amyloid polyneuropathy-FAP)or the heart(familial amyloid cardiomyopathy).In rare cases,aggregation develops in the central nervous system,giving rise to a phenotype known as familial leptomeningeal amyloidosis(Carroll et al.,2022).展开更多
文摘The purpose of this paper is to study the theory of conservative estimating functions in nonlinear regression model with aggregated data. In this model, a quasi-score function with aggregated data is defined. When this function happens to be conservative, it is projection of the true score function onto a class of estimation functions. By constructing, the potential function for the projected score with aggregated data is obtained, which have some properties of log-likelihood function.
文摘The concept of aggregated signal is introduced. Quantitatively, an aggregated signal can be defined as the scalar signal: it accumulates in its own variations only those spectral components that are presented simultaneously in each scalar time series of the multidimensional signal to be analyzed. Moreover, an algorithm of aggregation is proposed to suppress the spectral components that are present in any of the scalar components but absent in others (these components can be called local disturbance signals, for instance of technogenic nature). The main purpose of constructing the aggregated signal is to make clearer the common tendency of low-frequency data-flow in geophysical networks, which indicates an increase in collective behavior.It is known that almost all models of the process of earthquake preparation have pointed out an increase in collective behavior of components of geophysical fields in the region of preparation when the coming geocatastrophe has entered its long- and mid-term stages.
基金The Project was supported by the National Key Projects for Fundamental Research"Macromolecular Condensed State",The State Science and Technology Commission of China
文摘The structural parameters of the aggregated state of polyamide (PA)-1010 annealed at various temperatures were computed by means of the desmearing intensity from Smalt Angle X-ray Scattering (SAXS) measurements and by using the concept of the distance distribution function. The results indicated that the structural parameters of the aggregated state were strongly dependent upon heat treatment conditions and the maximum values of the structural parameters were obtained for the samples annealed at T = 175 degrees C. The particle size Z annealed at different temperature was ranged between 8.1-12.8nm, and the values of the distance distribution function P-max(Z) were obtained when Z = 4.0-6.8 nm. Using one dimension electron density correlation function (1D EDCF) method long period (L) and thickness of the lamellar (d(0)) were estimated and were found to increase with the increase of the degree of crystallinity.
文摘Assembling of a few particles into a cluster commonly occurs in many systems.However,it is still challenging to precisely control particle assembling,due to the various amorphous structures induced by thermal fluctuations during cluster formation.Although these structures may have very different degrees of aggregation,a quantitative method is lacking to describe them,and how these structures evolve remains unclear.Therefore a significant step towards precise control of particle self-assembly is to describe and analyze various aggregation structures during cluster formation quantitatively.In this work,we are motivated to propose a method to directly count and quantitatively compare different aggregated structures.We also present several case studies to evaluate how the aggregated structures during cluster formation are affected by external controlling factors,e.g.,different interaction ranges,interaction strengths,or anisotropy of attraction.
文摘The alpha stable self-similar stochastic process has been proved an effective model for high variable data traffic. A deep insight into some special issues and considerations on use of the process to model aggregated VBR video traffic is made. Different methods to estimate stability parameter a and self-similar parameter H are compared. Processes to generate the linear fractional stable noise (LFSN) and the alpha stable random variables are provided. Model construction and the quantitative comparisons with fractional Brown motion (FBM) and real traffic are also examined. Open problems and future directions are also given with thoughtful discussions.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.20473078) and the Specialized Research Fund for the Doctoral Program of Higher Education (No.200803580022).
文摘Resonance Raman spectra of aggregated meso-tetra(4-pyridinium)porphyrin diacid (H8TPyP^6+) were studied with excitation near the exciton absorption bands of 470 nm. The UV-Vis absorption and resonance light scattering spectra of HsTPyP^6+ monomers and aggregates were also measured. The observed Raman bands of monomeric and aggregated HsTPyP^6+ were assigned on the basis of the observed deuteration shifts and by comparing with the Raman spectra of analogous porphyrin diacids. Aggregation causes moderate downshifts (2-6 cm^-1) for high-frequency modes involving the in-plane CC/CN stretches of the porphyrin core and a dramatic upshift (12 cm^-1) for the out-of-plane saddling mode of the porphyrin ring. The structural changes induced by aggregation and the possible hydrogen bonding interaction between the HsTPyP^6+ molecules in the aggregate are discussed based on the spectral observations.
文摘Aggregation is used to represent the real world in a model at an appropriate level of abstraction.We used the convection-diffusion equation to examine the implications of aggregation progressing from a three-dimensional(3D)spatial description to a model representing a system as a single box that exchanges sediment with the adjacent environment.We highlight how all models depend on some forms of parametric closure,which need to be chosen to suit the scale of aggregation adopted in the model.All such models are therefore aggregated and make use of some empirical relationships to deal with sub-scale processes.One such appropriately aggregated model,the model for the aggregated scale morphological interaction between tidal basin and adjacent coast(ASMITA),is examined in more detail and used to illustrate the insight that this level of aggregation can bring to a problem by considering how tidal inlets and estuaries are impacted by sea level rise.
基金the Korea Science and Engineering Foundation(2002-201-02-2)
文摘[KG(0.01mm]This study focuses on the community structure of aggregated bacteria in Lake Baikal and relationships with free-living bacteria. Fluorescent in situ hybridization (FISH) methods were used in samples of bacteria taken in April, 2001. Bacterial counts of free-living bacteria by DAPI staining ranged from 0.2×10 6 to 3.2×10 6 cells·mL -1, decreasing with depth, whereas aggregated bacterial numbers dramatically increased with depth, ranging from 0.4×10 4 to 3.3×10 4 cells·mL -1. Ratios of EUB probe binding cells to DAPI counts ranged from 52.3 to 74.1% in free-living bacteria and from 39.6 to 66.7% in aggregated bacteria, respectively. Community composition of aggregated bacteria was very different from free-living bacteria, especially at 25m depth where highest phytoplankton numbers were observed. The vertical profile of aggregated bacteria community was very characteristic. Beta-Proteobacteria increased with depth down to 100m. At 250m, gamma-Proteobacteria was 44% of DAPI bound cells, while other groups were less than 1%. We conclude that community structures of free-living and aggregated bacteria were different, and they may sustain the ecosystem in independent ways.
基金the Taif University Researchers Supporting Project number(TURSP-2020/36),Taif University,Taif,Saudi Arabiafundedby Princess Nourah bint Abdulrahman University Researchers Supporting Project Number(PNURSP2022R97), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia。
文摘NonorthogonalMultiple Access(NOMA)is incorporated into the wireless network systems to achieve better connectivity,spectral and energy effectiveness,higher data transfer rate,and also obtain the high quality of services(QoS).In order to improve throughput and minimum latency,aMultivariate Renkonen Regressive Weighted Preference Bootstrap Aggregation based Nonorthogonal Multiple Access(MRRWPBA-NOMA)technique is introduced for network communication.In the downlink transmission,each mobile device’s resources and their characteristics like energy,bandwidth,and trust are measured.Followed by,the Weighted Preference Bootstrap Aggregation is applied to recognize the resource-efficient mobile devices for aware data transmission by constructing the different weak hypotheses i.e.,Multivariate Renkonen Regression functions.Based on the classification,resource and trust-aware devices are selected for transmission.Simulation of the proposed MRRWPBA-NOMA technique and existing methods are carried out with different metrics such as data delivery ratio,throughput,latency,packet loss rate,and energy efficiency,signaling overhead.The simulation results assessment indicates that the proposed MRRWPBA-NOMA outperforms well than the conventional methods.
文摘In this paper, component carrier selection and beamforming on carrier aggregated channels in Heterogeneous Networks are proposed. The scheme jointly selects the component carrier and precoding (i.e. beamforming) vectors with the cooperation of the other cells to deal with the interference between Macro cell and Pico cell. The component carrier selection and beamforming is achieved by optimizing the multi-cell downlink throughput. This optimization results in shutting down a subset of the component carrier in order to allow for a perfect interference removal at the receive side in the dense low power node deployment scenario. Additionally, algorithm based on Branch and Bound Method is used to reduce the search complexity of the algorithm. Simulation results show that the proposed scheme can achieve high cell-average and cell-edge throughput for the Pico cell in the Heterogeneous Networks.
文摘Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate the contribution of conservation farming technology or reduced tillage in potato-based rotations in the Colombian Andes in order to rehabilitate total and aggregated soil organic C in disturbed organic matter-rich Andisols. Soils were sampled from farms with 7-year of reduced tillage and farms with conventional farming practices. Ultrasound energy was applied to samples to disrupt aggregation and total soil C was determined in order to investigate the amount of carbon held inside the aggregates of different soil size classes. Results indicated that reduced tillage in potato-based crop rotations increased the soil C concentration and average C content in the whole profile (≈117 cm depth) by 50 and 33% (1636 t C ha?1 vs. 1224 t C ha?1), respectively, as compared to conventional farming practices. Carbon content increased 177% in the subsoil (A2 horizon, 78 -117 cm depth, from 215 to 596 t?ha?1), although most of the soil C was in the A1 horizon (between 0 -78 cm average thickness, 1097 t?ha?1). These increases show that reduced tillage enhances C stores in Andisols which are already high in organic matter. In addition, C in aggregates represented more than 80% of the total organic matter and it was positively affected by conservation practices. The C increase was preferential in the smaller macroaggregates (
文摘Cognitive Radio (CR) is a promising technology to increase the efficiency of spectrum by opportunistic access. However, in many cases the sensed spectrum is so broken that it cannot be utilized sufficiently with traditional continuous spectrum allocation strategy. Spectrum aggregation can make full use of narrow spectrum fragments while the overhead it brings may reduce the overall performance of the system. This paper proposes a Mixed Contiguous and Aggregated Spectrum Allocation (MixCASA) algorithm for CR based TD-LTE Networks. This algorithm combines contiguous with discontiguous spectrum allocation together in order to guarantee the feasibility and efficiency of system. Simulation results show that the MixCASA algorithm can increase the number of allocated channels, and reduce the overhead brought by excessive spectrum aggregation as well.
基金National Natural Science Foundation of China,Grant/Award Numbers:51933010,22203028。
文摘Donor–acceptor(D-A)conjugated polymers have demonstrated great potential in organicfield-effect transistors application,and their aggregated structure is a crucial factor for high charge mobility.However,the aggregated structure of D-A conjugated polymerfilms is complex and the structure–property relationship is difficult to understand.This review provides an overview of recent progress in controlling the aggregated structure of D-A conjugated polymerfilms for higher mobility,including the mechanisms,methods,and properties.Wefirst discuss the multilevel microstructures of D-A conjugated polymerfilms,and then summarize the current understanding of the relationship betweenfilm microstructures and charge transport properties.Subsequently,we review the theory of D-A conjugated polymer crystallization.After that,we summarize the common methods to control the aggregated structure of semi-crystalline and near-amorphous D-A conjugated polymerfilms,such as crystallites and aggregates,tie chains,film alignment,and attempt to understand them from the basic theory of polymer crystallization.Finally,we provide the current challenges in controlling the aggregated structure of D-A conjugated polymerfilms and in understanding the structure–property relationship.
基金support by National Natural Science Foundation of P.R.C. (70901069)Ministry of Education Foundation of Humanities and Social Sciences of P.R.C. (10YJC630208)+1 种基金Key Foundation of Natural Science for Colleges and Universities in Anhui, China (KJ2011A001) Social Science Foundation of Anhui, China (AHSK07-08D25, AHSKF09-10D116, AHSK09-10D14)
文摘Data Envelopment Analysis(DEA) and Ratio Analysis(RA) are two widely used methods for measuring units' productivity and any other criteria that could be assessed based on the available input and output variables.A number of researchers have studied DEA and RA and noted the positive and negative differences between them.Aggregated ratio analysis(ARA) model,which provide an important linkage between DEA and RA theory,is equivalent to the CCR DEA model,and this equivalence property offers a great deal of opportunities for DEA to be interpreted and applied in different ways.This paper extends the results of ARA model and proposes an extended aggregated ratio analysis(EARA) model,similar as the development from CCR model to BCC model in DEA context.The proposed model can offer an insight into the characteristic of returns to scale,playing the corresponding role as BCC model does.The numerical example is revisited in the paper and the results are compared.
基金Open Fund of the Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications(Jinan University)National Natural Science Foundation of China(NSFC)(11274395,11774135,61205165)
文摘Aggregation of metal nanoparticles plays an important role in surface enhanced Raman scattering (SERS). Here, a strategy of dynamically aggregating/releasing gold nanopartides is demonstrated using a gold-nanofilm-coated nanofiber, with the assistance of enhanced optical force and plasmonic photothermal effect. Strong SERS signals of rhodamine 6G are achieved at the hotspots formed in the inter-particle and film-partide nanogaps. The proposed SERS substrate was demonstrated to have a sensitivity of 10-12 M, reliable reproducibility, and good stability.
基金National Natural Science Foundation of China,Grant/Award Number:52073207National Key Research and Development Program of China,Grant/Award Number:2019YFA0705900MOST and the Basic and Applied Basic Research Major Program of Guangdong Province,Grant/Award Number:2019B030302007。
文摘π-Conjugated organic/polymer materials-based solar cells have attracted tremendous research interest in the fields of chemistry,physics,materials science,and energy science.To date,the best-performance polymer solar cells(PSCs)have achieved power conversion efficiencies exceeding 18%,mostly driven by the molecular design and device structure optimization of the photovoltaic materials.This review article provides a comprehensive overview of the key advances and current status in aggregated structure research of PSCs.Here,we start by providing a brief tutorial on the aggregated structure of photovoltaic polymers.The characteristic parameters at different length scales and the associated characterization techniques are overviewed.Subsequently,a variety of effective strategies to control the aggregated structure of photovoltaic polymers are discussed for polymer:fullerene solar cells and polymer:nonfullerene small molecule solar cells.Particularly,the control strategies for achieving record efficiencies in each type of PSCs are highlighted.More importantly,the in-depth structure-performance relationships are demonstrated with selected examples.Finally,future challenges and research prospects on understanding and optimizing the aggregated structure of photovoltaic polymers and their blends are provided.
基金supported in part by the National Natural Science Foundation of China (No.U2166202)S&T Program of Hebei (No.20312102D)。
文摘With the increasing use of renewable resources and electric vehicles(EVs), the variability and uncertainty in their nature put forward a high requirement for flexibility in AC distribution system incorporating voltage source converter(VSC) based multi-terminal direct current(MTDC) grids. In order to improve the capability of distribution systems to cope with uncertainty, the flexibility enhancement of AC-MTDC distribution systems considering aggregated EVs is studied. Firstly, the charging and discharging model of one EV is proposed considering the users' demand difference and traveling needs. Based on this, a vehicle-to-grid(V2G) control strategy for aggregated EVs to participate in the flexibility promotion of distribution systems is provided. After that, an optimal flexible dispatching method is proposed to improve the flexibility of power systems through cooperation of VSCs, controllable distributed generations(CDGs), aggregated EVs, and energy storage systems(ESSs). Finally, a case study of an AC-MTDC distribution system is carried out. Simulation results show that the proposed dispatching method is capable of effectively enhancing the system flexibility, reducing renewable power curtailment, decreasing load abandonment, and cutting down system cost.
基金supported by Research Centre for Integrated Transport Innovation,UNSW
文摘This paper addresses the transportation network design problem (NDP) wherein the dis- tance limit and en-route recharge of electric vehicles are taken into account. Specifically, in this work, the network design problem aims to select the optimal planning policy from a set of infrastructure design scenarios considering both road expansions and charging station allocations under a specified construction budget. The user-equilibrium mixed-vehicular traffic assignment problem with en-route recharge (MVTAP-ER) is formulated into a novel convex optimization model and extended to a newly developed bi-level program of the aggregated NDP integrating recharge facility allocation (NDP-RFA). In the algorithmic framework, a convex optimization technique and a tailored CA are adopted for, respectively, solving the subproblem MVTAP-ER and the primal problem NDP-RFA. Systematic ex- periments are conducted to test the efficacy of the proposed approaches. The results highlight the impacts of distance limits and budget levels on the project selection and evaluation, and the benefits of considering both road improvement policy and recharge service provision as compared to accounting for the latter only. The results also report that the two design objectives, to respectively minimize the total system travel time and vehicle miles travelled, are conflicting for certain scenarios.
文摘Neurons are highly polarized cells with axons reaching over a meter long in adult humans.To survive and maintain their proper function,neurons depend on specific mechanisms that regulate spatiotemporal signaling and metabolic events,which need to be carried out at the right place,time,and intensity.Such mechanisms include axonal transport,local synthesis,and liquid-liquid phase separations.Alterations and malfunctions in these processes are correlated to neurodegenerative diseases such as amyotrophic lateral sclerosis(ALS).
基金funded by the Spanish Ministry of Science and Innovation(PDC2021-120914-I00)the Universitat Autònoma de Barcelona(PROOF OF CONCEPT 2020)ICREA,ICREA-Academia 2015 and 2020(to SV).
文摘The misfolding and subsequent aggregation of proteins into amyloid fibrils underlie the onset of a variety of human disorders collectively known as amyloidosis.Transthyretin(TTR)is one of the>30 amyloidogenic proteins identified to date and is associated with a group of highly debilitating and life-threatening disorders called TTR amyloidosis(ATTR).ATTR comprises senile systemic amyloidosis,which is linked to wild-type(WT)TTR aggregation,and hereditary ATTR,a dominantly inherited disorder caused by the deposition of one of over 130 TTR genetic variants.Senile systemic amyloidosis is a prevalent age-related amyloidosis,affecting up to 25%of the population over 80 years of age,and is characterized by the build-up of TTR fibrils in the myocardium.Regarding hereditary ATTR,the clinical presentation is highly heterogeneous,primarily affecting the peripheral nervous system(familial amyloid polyneuropathy-FAP)or the heart(familial amyloid cardiomyopathy).In rare cases,aggregation develops in the central nervous system,giving rise to a phenotype known as familial leptomeningeal amyloidosis(Carroll et al.,2022).