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Association of preschool children behavior and emotional problems with the parenting behavior of both parents 被引量:1
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作者 Su-Mei Wang Shuang-Qin Yan +4 位作者 Fang-Fang Xie Zhi-Ling Cai Guo-Peng Gao Ting-Ting Weng Fang-Biao Tao 《World Journal of Clinical Cases》 SCIE 2024年第6期1084-1093,共10页
BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.... BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors. 展开更多
关键词 CHILDREN Preschool age parentING BEHAVIORAL parenting problems
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Trajectory tracking guidance of interceptor via prescribed performance integral sliding mode with neural network disturbance observer 被引量:1
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作者 Wenxue Chen Yudong Hu +1 位作者 Changsheng Gao Ruoming An 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期412-429,共18页
This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost phase.Indeed,the velocity control in such trajectory tracking guidance system... This paper investigates interception missiles’trajectory tracking guidance problem under wind field and external disturbances in the boost phase.Indeed,the velocity control in such trajectory tracking guidance systems of missiles is challenging.As our contribution,the velocity control channel is designed to deal with the intractable velocity problem and improve tracking accuracy.The global prescribed performance function,which guarantees the tracking error within the set range and the global convergence of the tracking guidance system,is first proposed based on the traditional PPF.Then,a tracking guidance strategy is derived using the integral sliding mode control techniques to make the sliding manifold and tracking errors converge to zero and avoid singularities.Meanwhile,an improved switching control law is introduced into the designed tracking guidance algorithm to deal with the chattering problem.A back propagation neural network(BPNN)extended state observer(BPNNESO)is employed in the inner loop to identify disturbances.The obtained results indicate that the proposed tracking guidance approach achieves the trajectory tracking guidance objective without and with disturbances and outperforms the existing tracking guidance schemes with the lowest tracking errors,convergence times,and overshoots. 展开更多
关键词 BP network neural Integral sliding mode control(ISMC) Missile defense Prescribed performance function(PPF) State observer Tracking guidance system
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Closed-form guidance law for velocity maximization with impact angle constraint
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作者 ZHANG Jiahui WEN Qiuqiu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1295-1303,共9页
Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Theref... Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Therefore,this paper seeks to solve a type of optimal control problem that maximizes final velocity subject to equality point constraint of impact angle con-straint.It is proved that the crude problem of maximizing final velocity is equivalent to minimizing a quadratic-form cost of cur-vature.The closed-form guidance law is henceforth derived using optimal control theory.The derived analytical guidance law coincides with the widely-used optimal guidance law with impact angle constraint(OGL-IAC)with a set of navigation parameters of two and six.On this basis,the optimal emission angle is determined to further increase the final velocity.The derived optimal value depends solely on the initial line-of-sight angle and impact angle constraint,and thus practical for real-world appli-cations.The proposed guidance law is validated by numerical simulation.The results show that the OGL-IAC is superior to the benchmark guidance laws both in terms of final velocity and missing distance. 展开更多
关键词 MISSILE guidance law proportional-navigation guidance impact angle
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A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties
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作者 Tong Li Quhan Cheng +11 位作者 Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu Tang Zhongyang Liu Kai Wang 《Neural Regeneration Research》 SCIE CAS 2025年第7期2084-2094,共11页
Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduit... Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor site.As an alternative,nerve guidance conduits may be used.The ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve regeneration.We designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align them.Subsequently,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber lumen.The presence of aligned fibers on the inner surface can promote the extension of nerve cells along the fibers.The helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide stability.Our novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries. 展开更多
关键词 aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance
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Design methodology of a mini-missile considering flight performance and guidance precision
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作者 ZHANG Licong GONG Chunlin +1 位作者 SU Hua ANDREA Da Ronch 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期195-210,共16页
The design of mini-missiles(MMs)presents several novel challenges.The stringent mission requirement to reach a target with a certain precision imposes a high guidance precision.The miniaturization of the size of MMs m... The design of mini-missiles(MMs)presents several novel challenges.The stringent mission requirement to reach a target with a certain precision imposes a high guidance precision.The miniaturization of the size of MMs makes the design of the guidance,navigation,and control(GNC)have a larger-thanbefore impact on the main-body design(shape,motor,and layout design)and its design objective,i.e.,flight performance.Pursuing a trade-off between flight performance and guidance precision,all the relevant interactions have to be accounted for in the design of the main body and the GNC system.Herein,a multi-objective and multidisciplinary design optimization(MDO)is proposed.Disciplines pertinent to motor,aerodynamics,layout,trajectory,flight dynamics,control,and guidance are included in the proposed MDO framework.The optimization problem seeks to maximize the range and minimize the guidance error.The problem is solved by using the nondominated sorting genetic algorithm II.An optimum design that balances a longer range with a smaller guidance error is obtained.Finally,lessons learned about the design of the MM and insights into the trade-off between flight performance and guidance precision are given by comparing the optimum design to a design provided by the traditional approach. 展开更多
关键词 mini-missiles(MMs) guidance NAVIGATION and control(GNC)system multi-objective optimization multidisciplinary design optimization(MDO) flight performance guidance precision
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Metal reflector-enhanced thermoacoustic imaging as a guidance for puncture biopsy
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作者 Shuang Du Tao Qiang +1 位作者 Zihui Chi Huabei Jiang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第6期83-96,共14页
Puncture biopsy is an important clinical technique to obtain diseased tissue for pathological diagnosis,where imaging guidance is critical.In this paper,we describe a metal reflector-enhanced microwave-induced thermoa... Puncture biopsy is an important clinical technique to obtain diseased tissue for pathological diagnosis,where imaging guidance is critical.In this paper,we describe a metal reflector-enhanced microwave-induced thermoacoustic imaging(TAI)approach capable of guiding puncture biopsy for detection of breast cancer and joint diseases.Numerical experimentations simulating puncture guidance in breast cancer and knee gout models werefirst conducted using(CST STUDIO SUITE)(CST)software,and then ex-vivo experiments were performed followed by qualitative observations and semi-quantitative analysis.The results of both the simulations and ex-vivo experiments showed that our reflector-enhanced TAI could image the puncture needle in high resolution with a large depth of>12 cm. 展开更多
关键词 Microwave-induced thermoacoustic imaging puncture guidance REFLECTOR
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The Development of a Feeding Coparenting Scale for Japanese Parents of Fifth- and Sixth-Grade Elementary School Children
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作者 Maiko Yasuzato Tae Kawahara +2 位作者 Yuichi Nakayama Cin Cin Tan Akemi Yamazaki 《Open Journal of Nursing》 2024年第1期27-39,共13页
Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their ... Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their children was developed in the United States in 2019. However, there is no valid and reliable measure to assess feeding coparenting among caregivers of school-aged children in Japan. Therefore, this study aimed to develop a Japanese version of the FCS (FCS-J) questionnaire for caregivers with school-aged children. Methods: This was a web-based cross-sectional survey completed by caregivers of children aged 10-12 years. A preliminary survey using interviews and a web-based survey was conducted and found that the translated items of the FCS into Japanese were understandable to Japanese people. The developed survey was administered to parents of children at an elementary school. The reliability of the survey was assessed using both test-retest reliability and internal consistency analysis. Exploratory factor analysis was used to test construct validity, and known population validity was examined in relation to attributes, marital satisfaction, and feeding tasks. Results: Findings with 135 parents of school-aged children showed good internal reliability and validity of the FCS-J. The mean score for the overall FCS-J score was 46.2 (SD = 6.2), with Cronbach’s α of 0.72. For the subscales, Cronbach’s α ranged from 0.75 to 0.79. In sum, the present study’s results support the three-factor structure of the FCS in Japanese caregivers in Japan. Conclusions: The developed FCS-J was found to have a certain degree of reliability and validity. In this study, a Japanese version of the FCS-J was developed. . 展开更多
关键词 CHILD Coparenting parents Feeding Coparenting
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Cooperative guidance law based on super-twisting observer for target maneuvering
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作者 GAO Mengjing YAN Tian +3 位作者 HAN Bingjie CHENG Haoyu FU Wenxing HAN Bo 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1304-1314,共11页
To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is proposed.Firstly,th... To solve the problem that multiple missiles should simultaneously attack unmeasurable maneuvering targets,a guidance law with temporal consistency constraint based on the super-twisting observer is proposed.Firstly,the relative motion equations between multiple missiles and targets are established,and the topological model among multiple agents is considered.Secondly,based on the temporal consistency constraint,a cooperative guidance law for simultaneous arrival with finite-time convergence is derived.Finally,the unknown target maneuver-ing is regarded as bounded interference.Based on the second-order sliding mode theory,a super-twisting sliding mode observer is devised to observe and track the bounded interfer-ence,and the stability of the observer is proved.Compared with the existing research,this approach only needs to obtain the sliding mode variable which simplifies the design process.The simulation results show that the designed cooperative guidance law for maneuvering targets achieves the expected effect.It ensures successful cooperative attacks,even when confronted with strong maneuvering targets. 展开更多
关键词 cooperative guidance super-twisting target maneuver finite time convergence.
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Unified numerical predictor-corrector guidance based on characteristic model
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作者 MENG Bin ZHANG Hangning ZHAO Yunbo 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第4期40-49,共10页
Aerocapture is one of the key technologies for low-cost transportation,with high demands of autonomy,accuracy,and robustness of guidance and control,due to its high reliability requirements for only one chance of tryi... Aerocapture is one of the key technologies for low-cost transportation,with high demands of autonomy,accuracy,and robustness of guidance and control,due to its high reliability requirements for only one chance of trying.A unified numerical predictor-corrector guidance method based on characteristic models for aerocapture is proposed.The numerical predictor-corrector guidance method is used to achieve autonomy and high accuracy,and the characteristic model control method is introduced to achieve robustness.At the same time,by transforming path constraints,characteristic model equations including apogee deviation and altitude differentiation are established.Based on the characteristic model equations,a unified guidance law which can satisfy path constraints and guidance objectives simultaneously is designed.In guidance problems,guidance deviation is not directly obtained from the output of the dynamics at present,but is calculated through integral and algebraic equations.Therefore,the method of directly discretizing differential equations cannot be used to establish characteristic models,which brings great difficulty to characteristic modeling.A method for characteristic modeling of guidance problems is proposed,and convergence analysis of the proposed guidance law is also provided.Finally,a joint numerical simulation of guidance and control considering navigation deviation and various uncertainties is conducted to verify the effectiveness of the proposed method.The proposed unified method can be extended to general aerodynamic entry guidance designs,providing theoretical and methodological support for them. 展开更多
关键词 aerocapture path constraint characteristic model unified numerical predictor-corrector guidance CONVERGENCE
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Recorded recurrent deep reinforcement learning guidance laws for intercepting endoatmospheric maneuvering missiles
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作者 Xiaoqi Qiu Peng Lai +1 位作者 Changsheng Gao Wuxing Jing 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期457-470,共14页
This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with u... This work proposes a recorded recurrent twin delayed deep deterministic(RRTD3)policy gradient algorithm to solve the challenge of constructing guidance laws for intercepting endoatmospheric maneuvering missiles with uncertainties and observation noise.The attack-defense engagement scenario is modeled as a partially observable Markov decision process(POMDP).Given the benefits of recurrent neural networks(RNNs)in processing sequence information,an RNN layer is incorporated into the agent’s policy network to alleviate the bottleneck of traditional deep reinforcement learning methods while dealing with POMDPs.The measurements from the interceptor’s seeker during each guidance cycle are combined into one sequence as the input to the policy network since the detection frequency of an interceptor is usually higher than its guidance frequency.During training,the hidden states of the RNN layer in the policy network are recorded to overcome the partially observable problem that this RNN layer causes inside the agent.The training curves show that the proposed RRTD3 successfully enhances data efficiency,training speed,and training stability.The test results confirm the advantages of the RRTD3-based guidance laws over some conventional guidance laws. 展开更多
关键词 Endoatmospheric interception Missile guidance Reinforcement learning Markov decision process Recurrent neural networks
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A guidance strategy for rendezvous and docking to the space station in the Earth-Moon NRHO orbit
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作者 XIE Yongchun CHEN Changqing +1 位作者 LI Xiangyu LI Zhenyu 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第4期29-39,共11页
With the development of space technology,it is possible to build a space station in Earth-Moon space as a transit for Earth-Moon round-trip and entering in the deep space.Rendezvous and docking is one of the key techn... With the development of space technology,it is possible to build a space station in Earth-Moon space as a transit for Earth-Moon round-trip and entering in the deep space.Rendezvous and docking is one of the key technologies for building an Earth-Moon space station.A guidance strategy for rendezvous and docking from the Earth orbit to the space station in the Earth-Moon NRHO orbit is proposed in this paper,which is suitable for engineering applications.Firstly,the rendezvous and docking process is divided into three sections,i.e.,the large-range orbit transfer section,far-range guidance section,and close-range approaching section.The suitable terminal of large-range orbit transfer is selected according to the eigenvalue of NRHO orbit state transition matrix.The two-impulse guidance method based on the relative motion equation in the three-body problem is adopted for the far-range guidance section.The impulse time and amplitude are solved with the optimization algorithm.The linear constant three-body relative motion equation is proposed for the close-range approaching section,and the rendezvous and docking is completed by a two-stage linear approximation.Finally,a simulation analysis is carried out,and the simulation results show that the adopted dynamics equations and the designed guidance law are effective,and the three flight phases are naturally connected to accomplish the rendezvous and docking mission from the Earth orbit to the space station on the Earth-Moon NRHO. 展开更多
关键词 Earth-Moon space station rendezvous and docking NRHO orbit relative motion guidance strategy
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Missile guidance law design based on free-time convergent error dynamics
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作者 LIU Yuanhe XIE Nianhao +1 位作者 LI Kebo LIANG Yan’gang 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1315-1325,共11页
To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establis... To solve the finite-time error-tracking problem in mis-sile guidance,this paper presents a unified design approach through error dynamics and free-time convergence theory.The proposed approach is initiated by establishing a desired model for free-time convergent error dynamics,characterized by its independence from initial conditions and guidance parameters,and adjustable convergence time.This foundation facilitates the derivation of specific guidance laws that integrate constraints such as leading angle,impact angle,and impact time.The theoretical framework of this study elucidates the nuances and synergies between the proposed guidance laws and existing methodologies.Empirical evaluations through simulation comparisons underscore the enhanced accuracy and adaptability of the proposed laws. 展开更多
关键词 guidance design free-time convergence error dynamics approach impact angle constraint impact time constraint
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Main focus of parents of children with attention deficit hyperactivity disorder and the effectiveness of early clinical screening
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作者 Jia-Wen Li Ke Gao +1 位作者 Xiao-Yun Yang Zhi-Fei Li 《World Journal of Clinical Cases》 SCIE 2024年第19期3752-3759,共8页
BACKGROUND Attention deficit hyperactivity disorder(ADHD)is a common mental and behavioral disorder among children.AIM To explore the focus of attention deficit hyperactivity disorder parents and the effectiveness of ... BACKGROUND Attention deficit hyperactivity disorder(ADHD)is a common mental and behavioral disorder among children.AIM To explore the focus of attention deficit hyperactivity disorder parents and the effectiveness of early clinical screening METHODS This study found that the main directions of parents seeking medical help were short attention time for children under 7 years old(16.6%)and poor academic performance for children over 7 years old(12.1%).We employed a two-stage experiment to diagnose ADHD.Among the 5683 children evaluated from 2018 to 2021,360 met the DSM-5 criteria.Those diagnosed with ADHD underwent assessments for letter,number,and figure attention.Following the exclusion of ADHD-H diagnoses,the detection rate rose to 96.0%,with 310 out of 323 cases identified.RESULTS This study yielded insights into the primary concerns of parents regarding their children's symptoms and validated the efficacy of a straightforward diagnostic test,offering valuable guidance for directing ADHD treatment,facilitating early detection,and enabling timely intervention.Our research delved into the predominant worries of parents across various age groups.Furthermore,we showcased the precision of the simple exclusion experiment in discerning between ADHD-I and ADHD-C in children.CONCLUSION Our study will help diagnose and guide future treatment directions for ADHD. 展开更多
关键词 Attention deficit hyperactivity disorder CHILDREN parents Direction of attention Simple test
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Knowledge and practice skills on home-based urinary catheter care among parents of under-five children with urinary catheter
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作者 Kurvatteppa HALEMANI Sanjay DHIRAAJ +3 位作者 Basant KUMAR Saadhat HUSSAN Premalata Prerna PAWAN Priyanshi Raviraj GUPTA 《Journal of Integrative Nursing》 2024年第1期29-34,共6页
Objectives:The objectives of this study were to assess the knowledge and practice skills on home-based urinary catheter care among parents of under-five children with urinary catheter.Materials and Methods:This cross-... Objectives:The objectives of this study were to assess the knowledge and practice skills on home-based urinary catheter care among parents of under-five children with urinary catheter.Materials and Methods:This cross-sectional study was conducted from June 1,2021,to September 11,2021,in a tertiary hospital in north India.Purposive sampling was used to select 50 participants.Three instruments were employed for data collection after fulfilling sample criteria;for baseline information demographic tool,knowledge questionnaires,and a practice checklist.Data were analyzed using descriptive and inferential statistics.Results:On assessment of 50 participants,the majority of parents aged above 30 years(74%).Most of the participants were male(82%),graduated(38%),and working in the private sector(58%).Similarly,two-thirds of participants were residing in a nuclear family(64%)with a single child 32(64%)and family income<5000 rupees per month(60%).The mean score of knowledge was 1.94±0.81 and that of practice skills was 1.98±0.85 on home-based care.Regression analysis showed that knowledge of parents was significantly associated with qualification(β:1.821,P=0.002).Similarly,association of practice skills of parents with gender(β:1.235,P=0.050)and qualification(β:1.889,P=0.00)was significant.Conclusion:The general findings of our study showed that parents’education and occupation played a significant role in a child’s care.Parental education and catheter care skills positively affect the child and reduce readmission rates. 展开更多
关键词 Home-based care KNOWLEDGE parents PRACTICE urinary catheter
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Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve
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作者 Carina Hromada Patrick Heimel +10 位作者 Markus Kerbl LászlóGál Sylvia Nürnberger Barbara Schaedl James Ferguson Nicole Swiadek Xavier Monforte Johannes C.Heinzel Antal Nógrádi Andreas H.Teuschl-Woller David Hercher 《Neural Regeneration Research》 SCIE CAS 2025年第6期1789-1800,共12页
Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the ... Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use. 展开更多
关键词 axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit VASCULARIZATION
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The role of axon guidance molecules in the pathogenesis of epilepsy
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作者 Zheng Liu Chunhua Pan Hao Huang 《Neural Regeneration Research》 SCIE CAS 2025年第5期1244-1257,共14页
Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target no... Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with the pathogenicity of axon guidance molecules in epilepsy, offering a valuable reference for the exploration of therapeutic targets and presenting a fresh perspective on treatment strategies for this condition. 展开更多
关键词 axon guidance drug-resistant epilepsy EPILEPSY nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity NEURONS synaptic remodeling
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view
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作者 Wei Wang Jiaqi Liu +2 位作者 Shiyao Lin Baokui Geng Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期211-221,共11页
In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated... In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets. 展开更多
关键词 Integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer
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High Precision Guidance System of the Gravity-1 Launch Vehicle
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作者 ZHANG Jie XU Guoguang BU Xiangwei 《Aerospace China》 2024年第1期56-60,共5页
In the development of the Gravity-1 launch vehicle, solid rocket motors without a thrust termination mechanism created great challenges for ascent guidance. To resolve this problem, the Gravity-1 GNC system used cross... In the development of the Gravity-1 launch vehicle, solid rocket motors without a thrust termination mechanism created great challenges for ascent guidance. To resolve this problem, the Gravity-1 GNC system used cross product guidance in the core 2nd stage, and a nonlinear adaptive guidance algorithm in core 3rd stage, in order to achieve high orbit injection precision. On January 11, 2024, the Gravity-1 launch vehicle successfully carried out its maiden flight from a mobile sea platform off the coast of Haiyang in Shandong province, inserting its payload into a low earth orbit at an altitude of 500 kilometers, validating the guidance algorithm. 展开更多
关键词 Gravity-1 guidance system high precision
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Computational intelligence interception guidance law using online off-policy integral reinforcement learning
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作者 WANG Qi LIAO Zhizhong 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期1042-1052,共11页
Missile interception problem can be regarded as a two-person zero-sum differential games problem,which depends on the solution of Hamilton-Jacobi-Isaacs(HJI)equa-tion.It has been proved impossible to obtain a closed-f... Missile interception problem can be regarded as a two-person zero-sum differential games problem,which depends on the solution of Hamilton-Jacobi-Isaacs(HJI)equa-tion.It has been proved impossible to obtain a closed-form solu-tion due to the nonlinearity of HJI equation,and many iterative algorithms are proposed to solve the HJI equation.Simultane-ous policy updating algorithm(SPUA)is an effective algorithm for solving HJI equation,but it is an on-policy integral reinforce-ment learning(IRL).For online implementation of SPUA,the dis-turbance signals need to be adjustable,which is unrealistic.In this paper,an off-policy IRL algorithm based on SPUA is pro-posed without making use of any knowledge of the systems dynamics.Then,a neural-network based online adaptive critic implementation scheme of the off-policy IRL algorithm is pre-sented.Based on the online off-policy IRL method,a computa-tional intelligence interception guidance(CIIG)law is developed for intercepting high-maneuvering target.As a model-free method,intercepting targets can be achieved through measur-ing system data online.The effectiveness of the CIIG is verified through two missile and target engagement scenarios. 展开更多
关键词 two-person zero-sum differential games Hamilton–Jacobi–Isaacs(HJI)equation off-policy integral reinforcement learning(IRL) online learning computational intelligence inter-ception guidance(CIIG)law
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Design and Analysis of Terminal Guidance Law for Kinetic Interceptors based on Pulse Engine
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作者 Shixin Li Jia Ma Shuai Yue 《Journal of Electronic Research and Application》 2024年第5期95-108,共14页
A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-s... A new terminal guidance law is proposed based on a solid propellant pulse engine and an improved proportional navigation method to address the terminal guidance issue for kinetic interceptors.On this basis,the start-stop curve of the pulse motor during the terminal guidance process is designed,along with its start-up logic.The effectiveness of the proposed guidance strategy is verified through simulation. 展开更多
关键词 Pulse engine Terminal guidance law Kinetic interceptor Proportional navigation method
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