Modeling and control design of a bronchoscope robotics system

For the pulmonary nodule biopsy problem,this paper investigates an intervention robotics system based on the bronchoscope.To achieve precise control of the system,the mathematical model is established at first.The system mainly consists of an inserting tube and a tube tip,which are modeled based on a moving flexible beam and a soft robot,respectively.In order to reduce the harm to the patient during the operation,the robot system should suppress the vibration of the inserting tube during the process of tracking the desired trajectory in the bronchus.Therefore,we use the boundary control algorithm to design a controller capable of suppressing vibration for the inserting tube.Meanwhile,in order for the robot system to accurately select the bronchus corresponding to the branch,we designed a soft robot controller that can bend or deflect the soft robot to a specified posture.Finally,we used theoretical proof and numerical simulation to verify the conclusion.

Large Energy Capacitive High-Entropy Lead-Free Ferroelectrics

Advanced lead-free energy storage ceramics play an indispensable role in next-generation pulse power capacitors market.Here,an ultrahigh energy storage density of~13.8 J cm^(-3)and a large efficiency of~82.4%are achieved in high-entropy lead-free relaxor ferroelectrics by increasing configuration entropy,named high-entropy strategy,realizing nearly ten times growth of energy storage density compared with low-entropy material.Evolution of energy storage performance and domain structure with increasing configuration entropy is systematically revealed for the first time.The achievement of excellent energy storage properties should be attributed to the enhanced random field,decreased nanodomain size,strong multiple local distortions,and improved breakdown field.Furthermore,the excellent frequency and fatigue stability as well as charge/discharge properties with superior thermal stability are also realized.The significantly enhanced comprehensive energy storage performance by increasing configuration entropy demonstrates that high entropy is an effective but convenient strategy to design new high-performance dielectrics,promoting the development of advanced capacitors.

A Virtual Puncture Surgery System Based on Multi-Layer Soft Tissue and Force Mesh

Puncture is a common operation in surgery,which involves all kinds of tissue materials with different geometry and mechanical properties.As a new cross-disciplinary research area,Virtual Surgery(VS)makes simulation of soft tissue in puncture operation possible in virtual environment.In this paper,we introduce a VS-based puncture system composed by three-layer soft tissue,simulated with spherical harmonic function(SHF),which is covered with a force mesh,constructed by mass spring model(MSM).The two models are combined together with a parameter of SHF named surface radius,which provides MSM with real-time deformation data needed in force calculation.Meanwhile,force calculation,divided into the surface spring force and the puncture damping force,makes the force presentation better accord to the corresponding tissue characteristics.Moreover,a deformation resumption algorithm is leveraged to simulate the resumption phenomenon of the broken tissue surface.In evaluation experiment,several residents are invited to grades our model along with other four mainstream soft tissue models in terms of 7 different indicators.After the evaluation,the scores are analyzed by a comprehensive weighted grading method.Experiment results show that the proposed model has better performance during puncture operation than other models,and can well simulate surface resumption phenomenon when tissue surface is broken.

A Multi-Conditional Proxy Broadcast Re-Encryption Scheme for Sensor Networks

In sensor networks,it is a challenge to ensure the security of data exchange between packet switching nodes holding different private keys.In order to solve this problem,the present study proposes a scheme called multi-conditional proxy broadcast re-encryption(MC-PBRE).The scheme consists of the following roles:the source node,proxy server,and the target node.If the condition is met,the proxy can convert the encrypted data of the source node into data that the target node can directly decrypt.It allows the proxy server to convert the ciphertext of the source node to a new ciphertext of the target node in a different group,while the proxy server does not need to store the key or reveal the plaintext.At the same time,the proxy server cannot obtain any valuable information in the ciphertext.This paper formalizes the concept of MC-PBRE and its security model,and proposes a MC-PBRE scheme of ciphertext security.Finally,the scheme security has been proved in the random oracle.

Cognitive impairment associated with individual and joint exposure to PM_(2.5)constituents in a Chinese national cohort

Nationwide longitudinal evidence linking cognitive decline with exposure to fine particulate matter(PM_(2.5))constituents remains scarce in China.By constructing a dynamic cohort based on the China Health and Retirement Longitudinal Study,we aimed to assess individual and joint associations of PM_(2.5)constituents with cognitive function among middle-aged and older adults in China.Linear mixed-effects models incorporated with quantile-based g-computation were applied to investigate individual and joint associations of long-term exposures to PM_(2.5)constituents with cognitive function.Among 13,507 respondents,we evaluated 38,950 follow-up records of cognitive function tests.Declines in global cognitive score associated with an interquartile range(IQR)increase in exposure were−1.477(95%CI:−1.722,−1.232)for nitrate,followed by−1.331(−1.529,−1.133)for ammonium,−1.033(−1.184,−0.883)for sulfate,−0.988(−1.144,−0.832)for organic matter and−0.822(−0.946,−0.699)for black carbon.An IQR-equivalent increase in joint exposure to these PM_(2.5)constituents was associated with a decline of−1.353(−1.659,−1.048)in global cognitive score.Female,younger,and well-educated individuals were at greater vulnerability to cognitive impairment related to individual and joint exposure to PM_(2.5)constituents.This study suggested that later-life exposures to PM_(2.5)constituents were associated with cognitive decline in middle-aged and older adults in China.

Multi-phase structure and electrical properties of Bi_(0.5)Li_(0.5)ZrO_3 doping K_(0.48)Na_(0.56)NbO_3 lead-free piezoelectric ceramics

(1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3(KNN–x BLZ, x = 0–0.06) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method, and their phase structures and electric properties as well as T_C were systematically investigated. The orthorhombic–tetragonal(O–T) two phases were detected in all(1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3 ceramics at 0.01 ≤ x ≤ 0.05. Due to the appropriate ratio between O phase and T phase(CO/C T= 45/55), high piezoelectric properties of d 33= 239 pC/N, k_p= 34%, and P_r = 25.23 μC/cm^2 were obtained at x = 0.04. Moreover, a high T_C = 348 ℃ was also achieved in KNN–x BLZ ceramic at x = 0.04. These results indicate that (1–x)K_(0.48)Na_(0.56)NbO_3–xBi_(0.5)Li_(0.5)ZrO_3 system is a promising candidate for high-temperature piezoelectric devices.

Commensal microbiota and host metabolic divergence are associated with the adaptation of Diploderma vela to spatially heterogeneous environments

Heterogeneous environment adaptation is critical to understand the species evolution and response to climate change.However,how narrow-range species adapt to micro-geographic heterogeneity has been overlooked,and there is a lack of insights from metabolism and commensal microbiota.Here,we studied the environmental adaptation for 3 geographic populations(>40 km apart)of Diploderma vela,a lizard endemic to dry-hot valleys of the Hengduan Mountain Region.The climatic boundary caused a cooler,droughtier,and barren environment for northernmost population(RM)than the middle(QZK)and southernmost populations(FS).Correspondingly,significant divergences in liver and muscle metabolism and commensal microbiota were detected between RM and QZK or FS individuals,but not between QZK and FS individuals.Phospholipid composition,coenzyme level(i.e.pyridoxal and NAD^(+)),and cholesterol metabolism(e.g.androgen and estriol synthesis)constituted the major metabolic difference between RM and QZK/FS groups.FS and QZK individuals kept abundant Proteobacteria and antifungal strains,while RM individuals maintained more Firmicutes and Bacteroidota.Strong associations existed between varied host metabolite and gut microbes.How were these interpopulation variations associated to the environment adaptation were discussed.These results provided some novel insights into the environmental adaptation and implicated the consequence of climate change on narrow-range species.

Efficient CHzNHzPbl3 perovskite solar cells with 2TPA- n-DP hole-transporting layers

CH3NH3PbI3 perovskite solar cells with 2TPA-n-DP （TPA = 4,4＇-（（1E, I＇E,3E,3＇E）- [1,1＇-biphenyl]4,4＇-diylbis（buta-1,3-diene-4,1-diyl））; DP = bis（N,N-di-p-tolylaniline）; n = 1, 2, 3, 4） as hole-transporting materials （HTMs） have been fabricated. After optimization of the mesoporous TiO2 film thickness, devices based on 2TPA- 2-DP with power conversion efficiencies （PCEs） of up to 12.96% have been achieved, comparable to those of devices with （2,2＇,7,7＇-tetrakis（N,N-di-p- methoxyphenylamine）-9,9＇-spirobifluorene） （spiro-OMeTAD） as HTM under similar conditions. Further time-resolved photoluminescence （PL） measurements showed a fast charge transfer process at the perovskite/2TPA-2-DP interface. With the aid of electrochemical impedance spectra, a study of the electron blocking ability of 2TPA-2-DP in the device reveals that the presence of 2TPA-2-DP can greatly increase charge transfer resistance at the HTM/Au interface in the device, thus reducing the recombination. Furthermore, the perovskite solar cells based on these four HTMs exhibit ~ood stability after testin~ for one month.

Genome-wide signatures of mammalian skin covering evolution

Animal body coverings provide protection and allow for adaptation to environmental pressures such as heat,ultraviolet radiation,water loss,and mechanical forces.Here,using a comparative genomics analysis of 39 mammal species spanning three skin covering types(hairless,scaly and spiny),we found some genes(e.g.,UVRAG,POLH,and XPC)involved in skin inflammation,skin innate immunity,and ultraviolet radiation damage repair were under selection in hairless ocean mammals(e.g.,whales and manatees).These signatures might be associated with a high risk of skin diseases from pathogens and ultraviolet radiation.Moreover,the genomes from three spiny mammal species shared convergent genomic regions(EPHB2,EPHA4,and NIN)and unique positively selected genes(FZD6,INVS,and CDC42)involved in skin cell polarity,which might be related to the development of spines.In scaly mammals,the shared convergent genomic regions(e.g.,FREM2)were associated with the integrity of the skin epithelium and epidermal adhesion.This study identifies potential convergent genomic features among distantly related mammals with the same skin covering type.

苏州工艺双年展刺绣艺术的融合创新

民间手工艺与当代艺术的跨界融合,是优秀传统文化传承发展新路径的创新探索方向,苏州工艺双年展将当代艺术与手工艺进行混融叙事,为中国民间手工艺特别是刺绣艺术与新材料、新技术、新媒介等领域的融合创新做出了积极探索。本文以此展览为切入点,分析当代艺术与传统文化结合的必要性,及这种融合创新的方式为艺术创作和传统工艺所带来的双向文化价值。

Invasion and defense of the basic social unit in a nonhuman primate society leads to sexual differences in the gut microbiome

Multilevel society is one of the most complex social systems in natural ecosystems and is a typical feature among some primates.Given the potential connection between social behavior and gut microbiome composition,the multilevel social system could affect the primate gut microbiome.Here,based on long-term observation(e.g.social unit dynamics,transfer,and behavior),we investigated this potential integrating 16S rRNA gene amplicon sequencing and behavior data in Yunnan snub-nosed monkeys(Rhinopithecus bieti),which possess a multilevel social group based on one male units(OMUs,each unit with several breeding females and their offspring)and all-male unit(AMU,several bachelor males residing together).We found that the mean unweighted Unifrac distance between adult males from different OMUs was significantly lower than that between adult females from different OMUs(paired Wilcoxon test,P=0.007).There was no significant difference in the mean unweighted Unifrac distance between females within the same OMU or between females from different OMUs.These findings indicated the potential connection between the defense and invasion of social units and the gut microbiome community in wild Yunnan snub-nosed monkeys.We speculated that the resident males of OMUs displaying a significantly higher similarity in the gut microbial community than that of adult females in separate OMUs might be associated with the sexual differences in their interactions and from previously having cohabitated together in the AMU.Therefore,this study suggested that multilevel societies might have an effect on the gut microbial community in this wild nonhuman primate species.

Fluid-inspired field representation for risk assessment in road scenes

Prediction of the likely evolution of traffic scenes is a challenging task because of high uncertainties from sensing technology and the dynamic environment.It leads to failure of motion planning for intelligent agents like autonomous vehicles.In this paper,we propose a fluid-inspired model to estimate collision risk in road scenes.Multi-object states are detected and tracked,and then a stable fluid model is adopted to construct the risk field.Objects’state spaces are used as the boundary conditions in the simulation of advection and diffusion processes.We have evaluated our approach on the public KITTI dataset;our model can provide predictions in the cases of misdetection and tracking error caused by occlusion.It proves a promising approach for collision risk assessment in road scenes.