Collective Molecular Machines: Multidimensionality and Reconfigurability

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical work.During the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense research.Effective progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and informatics.However,individual molecular machines are only capable of producing nanometer work and generally have only a single functionality.In order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new paradigm.In this review,we comprehensively discuss recent developments in the collective behaviors of molecular machines.In particular,collective behavior is divided into two paradigms.One is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional materials.The other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale operations.We discuss design strategies for both modes and focus on the modulation of features and properties.Subsequently,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China

Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate.

Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections

To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended.

Reliable Data Collection Model and Transmission Framework in Large-Scale Wireless Medical Sensor Networks

Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical emergencies.However,the inherent instability and error-prone nature of wireless links present significant challenges,necessitating efficient data collection and reliable transmission services.This paper addresses the limitations of existing data transmission and recovery protocols by proposing a systematic end-to-end design tailored for medical event-driven cluster-based large-scale WSNs.The primary goal is to enhance the reliability of data collection and transmission services,ensuring a comprehensive and practical approach.Our approach focuses on refining the hop-count-based routing scheme to achieve fairness in forwarding reliability.Additionally,it emphasizes reliable data collection within clusters and establishes robust data transmission over multiple hops.These systematic improvements are designed to optimize the overall performance of the WSN in real-world scenarios.Simulation results of the proposed protocol validate its exceptional performance compared to other prominent data transmission schemes.The evaluation spans varying sensor densities,wireless channel conditions,and packet transmission rates,showcasing the protocol’s superiority in ensuring reliable and efficient data transfer.Our systematic end-to-end design successfully addresses the challenges posed by the instability of wireless links in large-scaleWSNs.By prioritizing fairness,reliability,and efficiency,the proposed protocol demonstrates its efficacy in enhancing data collection and transmission services,thereby offering a valuable contribution to the field of medical event-drivenWSNs.

Advances in Research of Collection and Detection Methods of Microplastics in Environment

As a new type of environmental pollutants,microplastics have gradually attracted people s attention.A large number of plastics discharged into the environment by human beings are constantly aging and breaking,and finally become microplastics.Microplastics can adsorb pollutants in the environment,and their components have certain toxicity,which can cause different degrees of harm to organisms.Due to the structural characteristics of microplastic particles,such as small particle size,large specific surface area,and their distribution in different environmental media,it is very difficult to accurately detect microplastics.Reliable collection and detection methods are the key to the study of environmental behavior of microplastics.In this study,the collection and detection methods of microplastics in the environment were reviewed,and the development direction of microplastics detection technology in the future was prospected.This study has a certain reference value for the related research and the prevention and treatment of micro-plastic pollution.

Association between acute peripancreatic fluid collections and early readmission in acute pancreatitis:A propensity-matched analysis

BACKGROUND Patients with acute pancreatitis(AP)frequently experience hospital readmissions,posing a significant burden to healthcare systems.Acute peripancreatic fluid collection(APFC)may negatively impact the clinical course of AP.It could worsen symptoms and potentially lead to additional complications.However,clinical evidence regarding the specific association between APFC and early readmission in AP remains scarce.Understanding the link between APFC and readmission may help improve clinical care for AP patients and reduce healthcare costs.AIM To evaluate the association between APFC and 30-day readmission in patients with AP.METHODS This retrospective cohort study is based on the Nationwide Readmission Database for 2016-2019.Patients with a primary diagnosis of AP were identified.Participants were categorized into those with and without APFC.A 1:1 propensity score matching for age,gender,and Elixhauser comorbidities was performed.The primary outcome was early readmission rates.Secondary outcomes included the incidence of inpatient complications and healthcare utilization.Unadjusted analyses used Mann-Whitney U andχ2 tests,while Cox regression models assessed 30-day readmission risks and reported them as adjusted hazard ratios(aHR).Kaplan-Meier curves and log-rank tests verified readmission risks.RESULTS A total of 673059 patients with the principal diagnosis of AP were included.Of these,5.1%had APFC on initial admission.After propensity score matching,each cohort consisted of 33914 patients.Those with APFC showed a higher incidence of inpatient complications,including septic shock(3.1%vs 1.3%,P<0.001),portal venous thrombosis(4.4%vs 0.8%,P<0.001),and mechanical ventilation(1.8%vs 0.9%,P<0.001).The length of stay(LOS)was longer for APFC patients[4(3-7)vs 3(2-5)days,P<0.001],as were hospital charges($29451 vs$24418,P<0.001).For 30-day readmissions,APFC patients had a higher rate(15.7%vs 6.5%,P<0.001)and a longer median readmission LOS(4 vs 3 days,P<0.001).The APFC group also had higher readmission charges($28282 vs$22865,P<0.001).The presence of APFC increased the risk of readmission twofold(aHR 2.52,95%confidence interval:2.40-2.65,P<0.001).The independent risk factors for 30-day readmission included female gender,Elixhauser Comorbidity Index≥3,chronic pulmonary diseases,chronic renal disease,protein-calorie malnutrition,substance use disorder,depression,portal and splenic venous thrombosis,and certain endoscopic procedures.CONCLUSION Developing APFC during index hospitalization for AP is linked to higher readmission rates,more inpatient complications,longer LOS,and increased healthcare costs.Knowing predictors of readmission can help target high-risk patients,reducing healthcare burdens.

Exploring Corporate Tax Compliance in the Era of Digital Tax Collection and Administration:Insights from the“Golden Tax Phase Four”Project

This article primarily examines the current state of tax collection and management,alongside other associated issues.It integrates insights from China’s“14th Five-Year Plan”and anticipates the imminent implementation of the“Golden Tax Phase Four.”With this backdrop,the article offers recommendations for advancing the reform of the tax collection and management system,fostering the development of intelligent taxation,and accelerating the modernization of tax collection and management in China.

Study on the Impact of Collective Commercial Construction Land Entering the Market on Rural Residents’Income:Taking Deqing County,Zhejiang Province as an Example

The entry of collective construction land for business purposes is an important measure for deepening the reform of the rural land system,promoting the flow of urban and rural factors,and realizing rural revitalization.Since the production of the first batch of pilot projects in 2015,33 county-level cities have participated in the pilot policy by 2023.Deqing County,Zhejiang Province,as the first area to participate in the pilot project,aims to achieve more fruitful results.This paper first examines how promoting farmers’income through the market entry of agricultural land can be achieved,then uses the synthetic control method to quantitatively study the impact of collective operational construction land on farmers’income using panel data from 2011 to 2019,and finally proposes relevant suggestions from the perspective of system reform.

Effects of sequential decay on collective flows and nuclear stopping power in heavy-ion collisions at intermediate energies

In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included.

Design and implementation of railway green performance basic data collection system

This study addressed the issues related to the collection and management of basic data for railway green performance. A railway green performance basic database has been constructed based on metadata and data exchange schemas. A data classification system has been established from the perspectives of businesses, processes,and entities. A BIM(Building Information Modelling) model data extraction scheme is proposed based on field similarity matching and a document content extraction scheme is proposed based on image recognition. A railway green performance basic data collection system has been developed, achieving efficient collection and integrated management of railway green performance basic data. This system can provide data support for applications such as railway carbon emissions accounting, green cost-benefit analysis, and evaluation of green design solutions.

Constructing Representative Collective Signature Protocols Using The GOST R34.10-1994 Standard

The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers.The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis,the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United States and Russian Federation.In this paper,we use the discrete logarithmic problem on prime finite fields,which has been implemented in the GOST R34.10-1994 digital signature standard,to build the proposed collective signature protocols.These protocols help to create collective signatures:Guaranteed internal integrity and fixed size,independent of the number of members involved in forming the signature.The signature built in this study,consisting of 3 components(U,R,S),stores the information of all relevant signers in the U components,thus tracking the signer and against the“disclaim of liability”of the signer later is possible.The idea of hiding the signer’s public key is also applied in the proposed protocols.This makes it easy for the signing group representative to specify which members are authorized to participate in the signature creation process.

Endoscopic intramural cystogastrostomy for treatment of peripancreatic fluid collection: A viewpoint from a surgeon

Percutaneous or endoscopic drainage is the initial choice for the treatment of peripancreatic fluid collection in symptomatic patients.Endoscopic transgastric fenestration(ETGF)was first reported for the management of pancreatic pseu-docysts of 20 patients in 2008.From a surgeon’s viewpoint,ETGF is a similar procedure to cystogastrostomy in that they both produce a wide outlet orifice for the drainage of fluid and necrotic debris.ETGF can be performed at least 4 wk after the initial onset of acute pancreatitis and it has a high priority over the surgical approach.However,the surgical approach usually has a better success rate because surgical cystogastrostomy has a wider outlet(>6 cm vs 2 cm)than ETGF.However,percutaneous or endoscopic drainage,ETGF,and surgical approach offer various treatment options for peripancreatic fluid collection patients based on their conditions.

NOMA Empowered Energy Efficient Data Collection and Wireless Power Transfer in Space-Air-Ground Integrated Networks

As the sixth generation network(6G)emerges,the Internet of remote things(IoRT)has become a critical issue.However,conventional terrestrial networks cannot meet the delay-sensitive data collection needs of IoRT networks,and the Space-Air-Ground integrated network(SAGIN)holds promise.We propose a novel setup that integrates non-orthogonal multiple access(NOMA)and wireless power transfer(WPT)to collect latency-sensitive data from IoRT networks.To extend the lifetime of devices,we aim to minimize the maximum energy consumption among all IoRT devices.Due to the coupling between variables,the resulting problem is non-convex.We first decouple the variables and split the original problem into four subproblems.Then,we propose an iterative algorithm to solve the corresponding subproblems based on successive convex approximation(SCA)techniques and slack variables.Finally,simulation results show that the NOMA strategy has a tremendous advantage over the OMA scheme in terms of network lifetime and energy efficiency,providing valuable insights.

LIM1863 is useful to explore collective cancer cell migration,and the group of heterogeneous cells undergoing collective migration behaves like a supracellular unit

Collective cancer cell migration(CCCM)and epithelial-to-mesenchymal transition(EMT)play key roles in metastasis.This study reports that the colorectal carcinoma cell line LIM1863 is useful for the study of CCCM and EMT.Methods:Hematoxylin and eosin staining,scanning electron microscopy,transmission electron microscopy,and western blot analysis were performed.Results:LIM1863 automatically grew as spheroids in suspension and had important typical epithelial properties,including several layers of cells arranged around a central lumen,apical-basal polarity,and types of cell-cell junctions.Treatment with a combination of both TGF beta 1 and TNF alpha induced definite and distinct EMT,a spheroid changing phenotype to form a monolayer high-confluent patch without lumen,without polarity.Spontaneous CCCM occurred in spheroids.Flat EMT cells adhered to the base of a dish,exhibited persistent movement as a cluster of cells,and then shed,resulting in a cluster.All cells from one cluster undergoing CCCM died.Otherwise,all cells undergoing EMT disappeared and almost all cells located in the cell reservoir survived and proliferated.Conclusion:LIM1863 is an excellent cell line to study CCCM and EMT.The group of heterogeneous cells undergoing CCCM behaves like a supracellular unit.

Autonomous UAV 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains

This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAV 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAV without losses and too long delays and minimizes the propulsion energy of the UAV.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm.

Experimental Study on the Resistance and Splash Performances of Water Collecting Devices for Mechanical Draft Cooling Towers

In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To explore the feasibility of this approach for mechanical draft cooling towers,a small-scale experimental device has been built to study the resistance and splash performances of three U-type water collecting devices(WCDs)for different water flow rates and wind speeds.The experimental results show that within the considered ranges of wind speed and water flow rate,the pressure drop of the different WCDs can vary significantly.The resistance and local splash performances can also be remarkably different.Some recommendations about the most suitable system are provided.Moreover,a regression analysis of the experimental data is conducted,and the resulting fitting formulas for resistance and splash performance of WCD are reported.

Joint UAV 3D deployment and sensor power allocation for energy-efficient and secure data collection

Unmanned aerial vehicles(UAVs) are advantageous for data collection in wireless sensor networks(WSNs) due to its low cost of use,flexible deployment,controllable mobility,etc. However,how to cope with the inherent issues of energy limitation and data security in the WSNs is challenging in such an application paradigm. To this end,based on the framework of physical layer security,an optimization problem for maximizing secrecy energy efficiency(EE) of data collection is formulated,which focuses on optimizing the UAV’s positions and the sensors’ transmit power. To overcome the difficulties in solving the optimization problem,the methods of fractional programming and successive convex approximation are then adopted to gradually transform the original problem into a series of tractable subproblems which are solved in an iterative manner. As shown in simulation results,by the joint designs in the spatial domain of UAV and the power domain of sensors,the proposed algorithm achieves a significant improvement of secrecy EE and rate.

Study on Rural Solid Waste Collection and Transportation Mode and Route Optimization Strategy in the Cold Regions of Northern China

Rural vitalization is a major strategy for reform and development of agriculture and rural areas in China,the key task of which is improving rural living environment.Imperfect rural solid waste(RSW)collection and transportation system exacerbates the pollution of RSW to rural living environment,while it has not been established and improved in the cold region of Northern China due to climate and economy.Through the analysis of the current situation of RSW source separation,collection,transportation and disposal in China,an RSW collection and transportation system suitable for the northern cold region was developed.Considering the low winter temperature in the northern cold region,different requirements for RSW collection,transportation and terminal disposal,scattered source points and single terminal disposal nodes in rural areas,the study focused on determining the number and location of transfer stations,established a model for transfer stations selection and RSW collection and transportation routes optimization for RSW collection and transportation system,and proposed the elite retention particle swarm optimization–genetic algorithm(ERPSO–GA).The rural area of Baiquan County was taken as a representative case,the collection and transportation scheme of which was given,and the feasibility of the scheme was clarified by simulation experiment.

Research on the Distribution of Incremental Benefits from the Entry of Collective Construction Land into the Market

In this paper,based on the process data of evaluating the benchmark land prices of collective construction land and agricultural land,the score of influencing factors is calculated,and a regression model between value-added benefits and influencing factors is established.According to the contribution of the government and collectives to value-added benefits,the distribution proportions of different purposes and levels are calculated.The research results show that there are significant differences in the distribution proportion of value-added income among different levels.The government distribution proportion decreases with the decrease of level,while the collective distribution proportion increases with the decrease of level.For each level of decrease in commercial service industry land and industrial and mining warehousing industry land,the government distribution proportion decreases by an average of 2.66%and 2.34%,while the collective distribution proportion increases by an average of 2.66%and 2.34%,respectively.The average distribution proportion of the government in the value-added income of commercial service industry land is 31.58%,which is much higher than the average income of 23.68%in the value-added income of industrial and mining warehousing industry land.