For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,...For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results.展开更多
In this paper Mei symmetry is introduced for a nonconservative system. The necessary and sufficient condition for a Mei symmetry to be also a Lie symmetry is derived. It is proved that the Mei symmetry leads to a non-...In this paper Mei symmetry is introduced for a nonconservative system. The necessary and sufficient condition for a Mei symmetry to be also a Lie symmetry is derived. It is proved that the Mei symmetry leads to a non-Noether conservative quantity via a Lie symmetry, and deduces a Lutzky conservative quantity via a Lie point symmetry.展开更多
Consider the following 2×2 nonlinear system:where f(u): R→R is a, smooth function. Setwhere F’(u)= f(u). Then (1) can be rewritten as an equivalent Hamiltonian system:
For a one-dimensional conservative system with position depending mass, one deduces consistently a constant of motion, a Lagrangian, and a Hamiltonian for the nonrelativistic case. With these functions, one shows the ...For a one-dimensional conservative system with position depending mass, one deduces consistently a constant of motion, a Lagrangian, and a Hamiltonian for the nonrelativistic case. With these functions, one shows the trajectories on the spaces (x,v) and (x,p) for a linear position depending mass. For the relativistic case, the Lagrangian and Hamiltonian cannot be given explicitly in general. However, we study the particular system with constant force and mass linear dependence on the position where the Lagrangian can be found explicitly, but the Hamiltonian remains implicit in the constant of motion.展开更多
Conservative chaotic systems have unique advantages over dissipative chaotic systems in the fields of secure communication and pseudo-random number generator because they do not have attractors but possess good traver...Conservative chaotic systems have unique advantages over dissipative chaotic systems in the fields of secure communication and pseudo-random number generator because they do not have attractors but possess good traversal and pseudorandomness. In this work, a novel five-dimensional(5D) Hamiltonian conservative hyperchaotic system is proposed based on the 5D Euler equation. The proposed system can have different types of coordinate transformations and time reversal symmetries. In this work, Hamilton energy and Casimir energy are analyzed firstly, and it is proved that the new system satisfies Hamilton energy conservation and can generate chaos. Then, the complex dynamic characteristics of the system are demonstrated and the conservatism and chaos characteristics of the system are verified through the correlation analysis methods such as phase diagram, equilibrium point, Lyapunov exponent, bifurcation diagram, and SE complexity. In addition, a detailed analysis of the multistable characteristics of the system reveals that many energy-related coexisting orbits exist. Based on the infinite number of center-type and saddle-type equilibrium points, the dynamic characteristics of the hidden multistability of the system are revealed. Then, the National Institute of Standards and Technology(NIST)test of the new system shows that the chaotic sequence generated by the system has strong pseudo-random. Finally, the circuit simulation and hardware circuit experiment of the system are carried out with Multisim simulation software and digital signal processor(DSP) respectively. The experimental results confirm that the new system has good ergodicity and realizability.展开更多
BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recom...BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recommended treatment involves the excision of bone fragments to facilitate athletes’early return to sports;excision surgery is also performed in trauma cases.However,some patients prefer nonsurgical treatment options,and conservative treatment should be considered.AIM To present a case series of 16 patients conservatively treated for hook of hamate fractures.METHODS This study included 16(11 males and 5 females;right side,6 cases;left side,10)patients who desired conservative treatment and could be followed-up until bone union was achieved.The average age of the patients was 49.6(range:24-72)years.The average time from injury to consultation was 4.3(range:0.2-21.4)weeks.The treatment involved 4 weeks of casting from the forearm to the metacarpophalangeal joint,followed by 8 weeks of splint fixation of the wrist.Follow-up computed tomography scans were performed every 4 weeks.RESULTS Bone union was achieved in all patients.The average duration of casting was 3.7(range:0-5)weeks and that of splint fixation thereafter was 8.6(range:0-28)weeks.The patients did not exhibit joint contractures or range of motion restrictions due to prolonged immobilization.CONCLUSION Conservative treatment with external fixation may be an option for hook of hamate fractures.展开更多
This commentary evaluates the case report by Mohammed et al on conservative management of ischiofemoral impingement through a multimodal physical therapy program integrating in-person sessions,telerehabilitation,dry n...This commentary evaluates the case report by Mohammed et al on conservative management of ischiofemoral impingement through a multimodal physical therapy program integrating in-person sessions,telerehabilitation,dry needling,and kinesiology taping.The study demonstrated significant pain reduction and functional improvement,highlighting the feasibility of hybrid care models.However,limitations include short-term follow-up,lack of post-treatment imaging,and single-case design restricting generalizability.Future research should prioritize longitudinal studies,anatomical correlation via imaging,and randomized trials to validate efficacy across diverse populations.While the framework offers promising clinical utility,further investigation is critical to optimize protocols and elucidate biomechanical mechanisms underlying symptom resolution.展开更多
This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical ...This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical intervention.In contrast to Scheufle et al’s report of 90%-100%failure rates with early surgical approaches,Tanaka and Yoshii’s protocol achieved universal healing despite delayed diagnoses in 25%of cases.Central to this success is the systematic inte-gration of high-resolution computed tomography for early diagnosis and dynamic monitoring of trabecular bone regeneration,significantly reducing missed dia-gnoses and guiding personalized immobilization timelines.The patient-centered strategy—allowing temporary splint removal during low-risk activities—balanced fracture stability with joint mobility preservation,avoiding post-treatment stiff-ness.However,limitations such as small sample size(n=16),selection bias,and insufficient long-term functional data(e.g.,grip strength,return-to-sport metrics)underscore the need for comparative trials.Emerging trends,including adjunct therapies like low-intensity pulsed ultrasound and biologics(e.g.,teriparatide),are proposed to accelerate healing while minimizing immobilization risks.This work redefines conservative fracture management paradigms,emphasizing in-novation without compromising efficacy.Overall,this assessment deepens our understanding of the conservative management of hook fractures and provides evidence-based insights for improved clinical decision-making.展开更多
Purpose:The aim of this study was to summarize the evidence regarding whether pain reduction in individuals with chronic non-specific low back pain(CNSLBP)following conservative interventions is related to correspondi...Purpose:The aim of this study was to summarize the evidence regarding whether pain reduction in individuals with chronic non-specific low back pain(CNSLBP)following conservative interventions is related to corresponding improvements in balance control.Methods:Randomized controlled trials were identified from 5 databases(MEDLINE,Cochrane Library,Embase,Web of Science,and PsycINFO).Two reviewers independently screened and identified relevant studies that investigated the effects of non-surgical or non-pharmacological CNSLBP treatments on both pain intensity and balance control.Meta-regression analyses were performed to establish the associations between post-treatment changes in these 2 variables.Results:Thirty one studies involving 1280 participants with CNSLBP were included.Moderate-quality evidence suggested that pain reduction was associated with and explained 34%-45%of decreases in body sway,as measured by center-of-pressure(CoP)area and CoP velocity with eyes open.However,no significant association was observed between pain reduction and CoP area or velocity in anteroposterior/mediolateral directions.Similarly,there was no significant association between pain reduction and CoP distance or radius.Low-quality evidence indicated that pain relief explained a 15%improvement in one-leg stance with eyes open but not in the eyes-closed condition.Additionally,very low-quality evidence suggested that pain relief explained a 44%decrease in the static anteroposterior stability index with eyes closed but not in the eyes-open,mediolateral,or overall conditions.Furthermore,low-quality evidence indicated that reduced pain was associated with and accounted for 25%-43%of the improved composite and posteromedial scores of the star-excursion balance test,rather than the anterior and posterolateral scores.Conclusion:Depending on the type of balance assessment,pain relief following conservative interventions may slightly to moderately enhance balance control in individuals with CNSLBP.Clinicians should pay close attention to the balance control in patients with CNSLBP,particularly among older adults.展开更多
BACKGROUND Enterocutaneous(EC)fistula incidence has been increasing in China,along with increases in the volume and complexity of surgeries.The conservative treatment strategy has been analyzed to improve the treatmen...BACKGROUND Enterocutaneous(EC)fistula incidence has been increasing in China,along with increases in the volume and complexity of surgeries.The conservative treatment strategy has been analyzed to improve the treatment outcomes for patients with EC fistulas and reduce the need for reoperation.AIM To analyze the clinical data of patients undergoing conservative treatment for EC fistulas and identify the factors that promote self-healing.These findings provide a reference for improving the clinical cure rate of EC fistulas with conservative treatment.METHODS The clinical data of 91 patients with EC fistulas who underwent conservative treatment were collected.The relationships between the cure rate and characteristics such as age,sex,body mass index,albumin level,primary disease,cause of the fistula,location of the fistula,number of fistulas,nature of the fistula,infection status,diagnostic methods,nutritional support methods,somatostatin therapy,growth hormone therapy,and fibrin glue therapy were analyzed.RESULTS A comparison of the basic patient characteristics between the two groups revealed statistically significant differences in primary disease(P=0.044),location of the fistula(P=0.006),number of fistulas(P=0.007),and use of adhesive sealing(χ2=12.194,P<0.001)between the uncured and cured groups.The use of fibrin glue was a significant factor associated with a cure for fistulas(odds ratio=5.459,95%CI:1.958-15.219,P=0.01).CONCLUSION The cure rate of patients with a single EC fistula can be effectively improved via conservative treatment combined with the use of biological fibrin glue to seal the fistula.展开更多
BACKGROUND Emphysematous gastritis(EG)is a rare and serious condition that has fatal consequences.Although its clinical presentation is not specific,radiological imaging is characterized by intramural gastric gas.Defe...BACKGROUND Emphysematous gastritis(EG)is a rare and serious condition that has fatal consequences.Although its clinical presentation is not specific,radiological imaging is characterized by intramural gastric gas.Defects in the stomach mucosal barrier and invasion of gas-producing organisms are believed to be the cause.CASE SUMMARY An 88-year-old male with multiple comorbidities presented to our center with abdominal pain and increased stoma output as chief complaints.Upon further investigation he was found to have EG.Despite the high mortality risk without intervention,the patient and family declined operative intervention.CONCLUSION This case report underscored the challenges of managing a critically ill elderly patient with a history of multiple comorbidities and extensive abdominal surgeries and highlighted the successful use of conservative measures in treating EG.展开更多
In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interfac...In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interface capturing(THINC)technique.We employ boundary variation diminishing(BVD)reconstruction to enhance the scheme’s effectiveness in handling shocks.First,we prove that wavelet collocation upwind schemes based on interpolating wavelets can be reformulated into a conservative form within the framework of wavelet theory,forming the foundation of the proposed scheme.The new fourthorder accurate scheme possesses significantly better spectral resolution than the fifth-and even seventh-order WENO-Z(weighted essentially non-oscillatory)schemes over the entire wave-number range.Moreover,the inherent low-pass filtering property of the wavelet bases allows them to filter high-frequency numerical oscillations,endowing the wavelet upwind scheme with robustness and accuracy in solving problems under extreme conditions.Notably,due to the wavelet multiresolution approximation,the proposed scheme possesses a distinctive shape-preserving property absent in the WENO-Z schemes and the fifth-order schemes with BVD reconstruction based on polynomials.Furthermore,compared to the fifth-order scheme with BVD reconstruction based on polynomials—which is significantly superior to the WENO schemes—the proposed scheme further enhances the ability to capture discontinuities.展开更多
This paper presents both analytical and numerical studies of the conservative Sawada-Kotera equation and its dissipative generalization,equations known for their soliton solutions and rich chaotic dynamics.These model...This paper presents both analytical and numerical studies of the conservative Sawada-Kotera equation and its dissipative generalization,equations known for their soliton solutions and rich chaotic dynamics.These models offer valuable insights into nonlinear wave propagation,with applications in fluid dynamics and materials science,including systems such as liquid crystals and ferrofluids.It is shown that the conservative Sawada-Kotera equation supports traveling wave solutions corresponding to elliptic limit cycles,as well as two-and three-dimensional invariant tori surrounding these cycles in the associated ordinary differential equation(ODE)system.For the dissipative generalized Sawada-Kotera equation,chaotic wave behavior is observed.The transition to chaos in the corresponding ODE systemfollows a universal bifurcation scenario consistent with the framework established by FShM(Feigenbaum-Sharkovsky-Magnitskii)theory.Notably,this study demonstrates for the first time that the conservative Sawada-Kotera equation can exhibit complex quasi-periodic wave solutions,while its dissipative counterpart admits an infinite number of stable periodic and chaotic waveforms.展开更多
Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to...Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions.展开更多
Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical ...Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical countries such as Uganda,agricultural expansion and wood fuel demand are its leading drivers.While the establishment of protected areas is a key tool in conserving remaining forest biodiversity,results indicate that current management does not sufficiently provide alternatives to forest resources utilised by households and income provided from timber and non-timber forest products.Beyond safeguarding ecosystems,protected areas need to ensure the sustainable socioeconomic development of adjacent communities for effective biodiversity conservation–however,both management and research often neglect to consider all dimensions.In this study,we analysed five decades of forest cover change in the Mount Elgon region,Uganda,by conducting a remote sensing analysis of its protected areas using Landsat MSS and TM data from 1973-2023 in combination with literature and subsequent interview analysis to consider both the ecological and socioeconomic dimension.We applied a random forest approach to differentiate forest and non-forest areas and carried out a pixel-based change detection analysis to differentiate temporal and spatial changes.Throughout the study period of 50 years,forest cover has evolved dynamically within the boundaries of the protected areas of Mount Elgon.A significant decline was observed in both Mount Elgon National Park with a loss of-5.98%(-46.83km²)and Mount Elgon Biosphere Reserve with a loss of-14.96%(-134.33km²).Our results showcase a cycle of deforestation and afforestation that could be tied to a series of development initiatives,re-demarcation of boundaries,changes in management and recurring evictions.Overall,the results lead to the conclusion that the lack of sustainable and efficient management and funding has fostered the rate of deforestation and accelerated ecological degradation in the region,but that existing problems are also rooted in the land tenure history of the region.We recommend the proper implementation of participatory and long-term management approaches on the ground and to address the land rights issue to contribute to both socioeconomic wellbeing and sustainable conservation outcomes.展开更多
The method of integrating factors is used to study the conservation laws of the Herglotz type Birkhoffian systems in this paper.Firstly,the definition of the integrating factors of the Herglotz type Birkhoffian system...The method of integrating factors is used to study the conservation laws of the Herglotz type Birkhoffian systems in this paper.Firstly,the definition of the integrating factors of the Herglotz type Birkhoffian systems is given.Secondly,the relationship between the integrating factors and conservation laws is studied,and the conservation theorems of Herglotz type Birkhoff's equations and their inverse theorems are established.Thirdly,two types of generalized Killing equations for calculating integrating factors are given.Finally,as an example,a linear damped oscillator is taken.This example can be transformed into a Herglotz type Birkhoffian system.The resulting conservation theorems are used to find the conserved quantities for this example.展开更多
In this paper,a variable-coefficient modified Kadomtsev-Petviashvili(vcm KP)system is investigated by modeling the propagation of electromagnetic waves in an isotropic charge-free infinite ferromagnetic thin film and ...In this paper,a variable-coefficient modified Kadomtsev-Petviashvili(vcm KP)system is investigated by modeling the propagation of electromagnetic waves in an isotropic charge-free infinite ferromagnetic thin film and nonlinear waves in plasma physics and electrodynamics.Painlevéanalysis is given out,and an auto-B?cklund transformation is constructed via the truncated Painlevéexpansion.Based on the auto-B?cklund transformation,analytic solutions are given,including the solitonic,periodic and rational solutions.Using the Lie symmetry approach,infinitesimal generators and symmetry groups are presented.With the Lagrangian,the vcm KP equation is shown to be nonlinearly self-adjoint.Moreover,conservation laws for the vcm KP equation are derived by means of a general conservation theorem.Besides,the physical characteristics of the influences of the coefficient parameters on the solutions are discussed graphically.Those solutions have comprehensive implications for the propagation of solitary waves in nonuniform backgrounds.展开更多
Traditional agricultural irrigation systems waste significant amounts of water and energy due to inefficient scheduling and the absence of real-time monitoring capabilities.This research developed a comprehensive IoT-...Traditional agricultural irrigation systems waste significant amounts of water and energy due to inefficient scheduling and the absence of real-time monitoring capabilities.This research developed a comprehensive IoT-based smart irrigation control systemto optimize water and energy management in agricultural greenhouses while enhancing crop productivity.The system employs a sophisticated four-layer Internet ofThings(IoT)architecture based on an ESP32 microcontroller,integrated with multiple environmental sensors,including soil moisture,temperature,humidity,and light intensity sensors,for comprehensive environmental monitoring.The system utilizes the Message Queuing Telemetry Transport(MQTT)communication protocol for reliable data transmission and incorporates a Random Forest machine learning algorithm for automated irrigation decision-making processes.The Random Forest model achieved exceptional performance with 99.3%overall accuracy,demonstrating high model reliability.Six operational modules were developed and implemented with three distinct control methods:manual operation,condition-based automatic control,and AI-driven intelligent control systems.A comprehensive one-month comparative analysis demonstrated remarkable improvements across multiple performance metrics:a 50%reduction in both water consumption(from 140 to 70 L/day)and energy usage(from 7.00 to 3.50 kWh/day),a substantial 130%increase in water use efficiency,and a significant 50%decrease in CO_(2) emissions.Furthermore,detailed factor importance analysis revealed soil moisture as the primary decision factor(38.6%),followed by temporal factors(20.3%)and light intensity(18.4%).The system demonstrates exceptional potential for annual energy conservation of 1277.5 kWh and CO_(2) emission reduction of 638.75 kg,contributing substantially to sustainable development goals and advancing smart agriculture technologies.展开更多
Water scarcity poses a significant challenge globally,with South Africa exemplifying the severe socio-economic and environmental impacts of limited water access.Despite advances in modern water management systems,the ...Water scarcity poses a significant challenge globally,with South Africa exemplifying the severe socio-economic and environmental impacts of limited water access.Despite advances in modern water management systems,the integration of indigenous knowledge(IK)into formal frameworks remains underutilized.This study systematically reviews the role of indigenous water conservation practices in South Africa,analyzing over 50 high-quality sources using the PRISMA methodology.The findings highlight the effectiveness of IK in addressing water scarcity through techniques such as rainwater harvesting,terracing,and wetland management,which are low-cost,environmentally sustainable,and deeply rooted in cultural practices.Indigenous methods also enhance climate resilience by enabling communities to adapt to droughts and floods through practices such as weather prediction and adaptive farming techniques.Furthermore,these practices foster social inclusivity and community empowerment,ensuring equitable water access and intergenerational knowledge transfer.The study underscores the potential of integrating IK with modern water technologies to create holistic solutions that are scalable,sustainable,and aligned with South Africa’s goal of achieving water security by 2030.Policy recommendations emphasize the need for institutional support,data collection,and financial incentives to sustain and mainstream indigenous approaches.By bridging the gap between traditional and contemporary systems,this research provides a roadmap for leveraging diverse knowledge systems to address water scarcity and build resilient communities.展开更多
This research paper addresses,from an ecogeographic perspective within a localised context,a new concept of nature conservation within modern farming systems:the direct seeding technique based on the principles of the...This research paper addresses,from an ecogeographic perspective within a localised context,a new concept of nature conservation within modern farming systems:the direct seeding technique based on the principles of the Conservation Agriculture System(CAS).The adoption of CAS aims to increase soil fertility,promote biodiversity,and sustain production,making it one of the most effective adaptation solutions available to address the challenges of climate change.CAS is defined as a farming system based on three key principles:minimal soil disturbance(reduced or zero tillage),maintaining a permanent soil cover(with residues from previous crops),and adopting crop rotation(diversifying crops rather than limiting them to a single type in consecutive seasons).However,there is limited research and a lack of scientific studies on the implementation of conservation agriculture in developing nations such as Morocco,particularly in the Had Kourt region.This study aims to assess the feasibility of CAS compared to traditional agricultural systems by surveying the opinions of farmers who have experience with both systems and comparing the outcomes of their practices based on simple indicators as an initial stage,with further analysis of additional indicators planned through subsequent scientific investigations.The sampling method used in this study is non-discriminatory,as semi-structured interviews were conducted with a group of farmers to gather their opinions on CAS.The adoption of conservation agriculture has been linked to prior knowledge of the system,acquired through training and fieldwork via application platforms,which remain limited in scope.展开更多
基金国家自然科学基金，湖南省自然科学基金，the Scientific Research Foundation of Education Burean of Hunan Province
文摘For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results.
基金Project supported by the State Key Laboratory of Scientific and Engineering Computing, Chinese Academy of Sciences and the National Natural Science Foundation of China （Grant Nos 10672143, 10471145 and 10372053） and the Natural Science Foundation of Henan Province Government of China（Grant Nos 0511022200 and 0311011400）.
文摘In this paper Mei symmetry is introduced for a nonconservative system. The necessary and sufficient condition for a Mei symmetry to be also a Lie symmetry is derived. It is proved that the Mei symmetry leads to a non-Noether conservative quantity via a Lie symmetry, and deduces a Lutzky conservative quantity via a Lie point symmetry.
基金Supported by NSFC (Grant No. 10071030) partially by Volkswagen Stiftung, Germany
文摘Consider the following 2×2 nonlinear system:where f(u): R→R is a, smooth function. Setwhere F’(u)= f(u). Then (1) can be rewritten as an equivalent Hamiltonian system:
文摘For a one-dimensional conservative system with position depending mass, one deduces consistently a constant of motion, a Lagrangian, and a Hamiltonian for the nonrelativistic case. With these functions, one shows the trajectories on the spaces (x,v) and (x,p) for a linear position depending mass. For the relativistic case, the Lagrangian and Hamiltonian cannot be given explicitly in general. However, we study the particular system with constant force and mass linear dependence on the position where the Lagrangian can be found explicitly, but the Hamiltonian remains implicit in the constant of motion.
基金Project supported by the Heilongjiang Province Natural Science Foundation Joint Guidance Project,China (Grant No.LH2020F022)the Fundamental Research Funds for the Central Universities,China (Grant No.3072022CF0801)。
文摘Conservative chaotic systems have unique advantages over dissipative chaotic systems in the fields of secure communication and pseudo-random number generator because they do not have attractors but possess good traversal and pseudorandomness. In this work, a novel five-dimensional(5D) Hamiltonian conservative hyperchaotic system is proposed based on the 5D Euler equation. The proposed system can have different types of coordinate transformations and time reversal symmetries. In this work, Hamilton energy and Casimir energy are analyzed firstly, and it is proved that the new system satisfies Hamilton energy conservation and can generate chaos. Then, the complex dynamic characteristics of the system are demonstrated and the conservatism and chaos characteristics of the system are verified through the correlation analysis methods such as phase diagram, equilibrium point, Lyapunov exponent, bifurcation diagram, and SE complexity. In addition, a detailed analysis of the multistable characteristics of the system reveals that many energy-related coexisting orbits exist. Based on the infinite number of center-type and saddle-type equilibrium points, the dynamic characteristics of the hidden multistability of the system are revealed. Then, the National Institute of Standards and Technology(NIST)test of the new system shows that the chaotic sequence generated by the system has strong pseudo-random. Finally, the circuit simulation and hardware circuit experiment of the system are carried out with Multisim simulation software and digital signal processor(DSP) respectively. The experimental results confirm that the new system has good ergodicity and realizability.
文摘BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recommended treatment involves the excision of bone fragments to facilitate athletes’early return to sports;excision surgery is also performed in trauma cases.However,some patients prefer nonsurgical treatment options,and conservative treatment should be considered.AIM To present a case series of 16 patients conservatively treated for hook of hamate fractures.METHODS This study included 16(11 males and 5 females;right side,6 cases;left side,10)patients who desired conservative treatment and could be followed-up until bone union was achieved.The average age of the patients was 49.6(range:24-72)years.The average time from injury to consultation was 4.3(range:0.2-21.4)weeks.The treatment involved 4 weeks of casting from the forearm to the metacarpophalangeal joint,followed by 8 weeks of splint fixation of the wrist.Follow-up computed tomography scans were performed every 4 weeks.RESULTS Bone union was achieved in all patients.The average duration of casting was 3.7(range:0-5)weeks and that of splint fixation thereafter was 8.6(range:0-28)weeks.The patients did not exhibit joint contractures or range of motion restrictions due to prolonged immobilization.CONCLUSION Conservative treatment with external fixation may be an option for hook of hamate fractures.
文摘This commentary evaluates the case report by Mohammed et al on conservative management of ischiofemoral impingement through a multimodal physical therapy program integrating in-person sessions,telerehabilitation,dry needling,and kinesiology taping.The study demonstrated significant pain reduction and functional improvement,highlighting the feasibility of hybrid care models.However,limitations include short-term follow-up,lack of post-treatment imaging,and single-case design restricting generalizability.Future research should prioritize longitudinal studies,anatomical correlation via imaging,and randomized trials to validate efficacy across diverse populations.While the framework offers promising clinical utility,further investigation is critical to optimize protocols and elucidate biomechanical mechanisms underlying symptom resolution.
文摘This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical intervention.In contrast to Scheufle et al’s report of 90%-100%failure rates with early surgical approaches,Tanaka and Yoshii’s protocol achieved universal healing despite delayed diagnoses in 25%of cases.Central to this success is the systematic inte-gration of high-resolution computed tomography for early diagnosis and dynamic monitoring of trabecular bone regeneration,significantly reducing missed dia-gnoses and guiding personalized immobilization timelines.The patient-centered strategy—allowing temporary splint removal during low-risk activities—balanced fracture stability with joint mobility preservation,avoiding post-treatment stiff-ness.However,limitations such as small sample size(n=16),selection bias,and insufficient long-term functional data(e.g.,grip strength,return-to-sport metrics)underscore the need for comparative trials.Emerging trends,including adjunct therapies like low-intensity pulsed ultrasound and biologics(e.g.,teriparatide),are proposed to accelerate healing while minimizing immobilization risks.This work redefines conservative fracture management paradigms,emphasizing in-novation without compromising efficacy.Overall,this assessment deepens our understanding of the conservative management of hook fractures and provides evidence-based insights for improved clinical decision-making.
基金supported by GP Batteries Industrial Safety Trust Fund(Funding number:R-ZDDR).
文摘Purpose:The aim of this study was to summarize the evidence regarding whether pain reduction in individuals with chronic non-specific low back pain(CNSLBP)following conservative interventions is related to corresponding improvements in balance control.Methods:Randomized controlled trials were identified from 5 databases(MEDLINE,Cochrane Library,Embase,Web of Science,and PsycINFO).Two reviewers independently screened and identified relevant studies that investigated the effects of non-surgical or non-pharmacological CNSLBP treatments on both pain intensity and balance control.Meta-regression analyses were performed to establish the associations between post-treatment changes in these 2 variables.Results:Thirty one studies involving 1280 participants with CNSLBP were included.Moderate-quality evidence suggested that pain reduction was associated with and explained 34%-45%of decreases in body sway,as measured by center-of-pressure(CoP)area and CoP velocity with eyes open.However,no significant association was observed between pain reduction and CoP area or velocity in anteroposterior/mediolateral directions.Similarly,there was no significant association between pain reduction and CoP distance or radius.Low-quality evidence indicated that pain relief explained a 15%improvement in one-leg stance with eyes open but not in the eyes-closed condition.Additionally,very low-quality evidence suggested that pain relief explained a 44%decrease in the static anteroposterior stability index with eyes closed but not in the eyes-open,mediolateral,or overall conditions.Furthermore,low-quality evidence indicated that reduced pain was associated with and accounted for 25%-43%of the improved composite and posteromedial scores of the star-excursion balance test,rather than the anterior and posterolateral scores.Conclusion:Depending on the type of balance assessment,pain relief following conservative interventions may slightly to moderately enhance balance control in individuals with CNSLBP.Clinicians should pay close attention to the balance control in patients with CNSLBP,particularly among older adults.
文摘BACKGROUND Enterocutaneous(EC)fistula incidence has been increasing in China,along with increases in the volume and complexity of surgeries.The conservative treatment strategy has been analyzed to improve the treatment outcomes for patients with EC fistulas and reduce the need for reoperation.AIM To analyze the clinical data of patients undergoing conservative treatment for EC fistulas and identify the factors that promote self-healing.These findings provide a reference for improving the clinical cure rate of EC fistulas with conservative treatment.METHODS The clinical data of 91 patients with EC fistulas who underwent conservative treatment were collected.The relationships between the cure rate and characteristics such as age,sex,body mass index,albumin level,primary disease,cause of the fistula,location of the fistula,number of fistulas,nature of the fistula,infection status,diagnostic methods,nutritional support methods,somatostatin therapy,growth hormone therapy,and fibrin glue therapy were analyzed.RESULTS A comparison of the basic patient characteristics between the two groups revealed statistically significant differences in primary disease(P=0.044),location of the fistula(P=0.006),number of fistulas(P=0.007),and use of adhesive sealing(χ2=12.194,P<0.001)between the uncured and cured groups.The use of fibrin glue was a significant factor associated with a cure for fistulas(odds ratio=5.459,95%CI:1.958-15.219,P=0.01).CONCLUSION The cure rate of patients with a single EC fistula can be effectively improved via conservative treatment combined with the use of biological fibrin glue to seal the fistula.
文摘BACKGROUND Emphysematous gastritis(EG)is a rare and serious condition that has fatal consequences.Although its clinical presentation is not specific,radiological imaging is characterized by intramural gastric gas.Defects in the stomach mucosal barrier and invasion of gas-producing organisms are believed to be the cause.CASE SUMMARY An 88-year-old male with multiple comorbidities presented to our center with abdominal pain and increased stoma output as chief complaints.Upon further investigation he was found to have EG.Despite the high mortality risk without intervention,the patient and family declined operative intervention.CONCLUSION This case report underscored the challenges of managing a critically ill elderly patient with a history of multiple comorbidities and extensive abdominal surgeries and highlighted the successful use of conservative measures in treating EG.
基金supported by the National Natural Science Foundation of China(Grant No.11925204).
文摘In this paper,we develop a fourth-order conservative wavelet-based shock-capturing scheme.The scheme is constructed by combining a wavelet collocation upwind method with the monotonic tangent of hyperbola for interface capturing(THINC)technique.We employ boundary variation diminishing(BVD)reconstruction to enhance the scheme’s effectiveness in handling shocks.First,we prove that wavelet collocation upwind schemes based on interpolating wavelets can be reformulated into a conservative form within the framework of wavelet theory,forming the foundation of the proposed scheme.The new fourthorder accurate scheme possesses significantly better spectral resolution than the fifth-and even seventh-order WENO-Z(weighted essentially non-oscillatory)schemes over the entire wave-number range.Moreover,the inherent low-pass filtering property of the wavelet bases allows them to filter high-frequency numerical oscillations,endowing the wavelet upwind scheme with robustness and accuracy in solving problems under extreme conditions.Notably,due to the wavelet multiresolution approximation,the proposed scheme possesses a distinctive shape-preserving property absent in the WENO-Z schemes and the fifth-order schemes with BVD reconstruction based on polynomials.Furthermore,compared to the fifth-order scheme with BVD reconstruction based on polynomials—which is significantly superior to the WENO schemes—the proposed scheme further enhances the ability to capture discontinuities.
文摘This paper presents both analytical and numerical studies of the conservative Sawada-Kotera equation and its dissipative generalization,equations known for their soliton solutions and rich chaotic dynamics.These models offer valuable insights into nonlinear wave propagation,with applications in fluid dynamics and materials science,including systems such as liquid crystals and ferrofluids.It is shown that the conservative Sawada-Kotera equation supports traveling wave solutions corresponding to elliptic limit cycles,as well as two-and three-dimensional invariant tori surrounding these cycles in the associated ordinary differential equation(ODE)system.For the dissipative generalized Sawada-Kotera equation,chaotic wave behavior is observed.The transition to chaos in the corresponding ODE systemfollows a universal bifurcation scenario consistent with the framework established by FShM(Feigenbaum-Sharkovsky-Magnitskii)theory.Notably,this study demonstrates for the first time that the conservative Sawada-Kotera equation can exhibit complex quasi-periodic wave solutions,while its dissipative counterpart admits an infinite number of stable periodic and chaotic waveforms.
基金supported by the National Natural Science Foun-dation of China(Grant No.72349002).
文摘Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions.
基金The financial support by the Deutsche Bundesstiftung Umwelt (DBU)
文摘Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical countries such as Uganda,agricultural expansion and wood fuel demand are its leading drivers.While the establishment of protected areas is a key tool in conserving remaining forest biodiversity,results indicate that current management does not sufficiently provide alternatives to forest resources utilised by households and income provided from timber and non-timber forest products.Beyond safeguarding ecosystems,protected areas need to ensure the sustainable socioeconomic development of adjacent communities for effective biodiversity conservation–however,both management and research often neglect to consider all dimensions.In this study,we analysed five decades of forest cover change in the Mount Elgon region,Uganda,by conducting a remote sensing analysis of its protected areas using Landsat MSS and TM data from 1973-2023 in combination with literature and subsequent interview analysis to consider both the ecological and socioeconomic dimension.We applied a random forest approach to differentiate forest and non-forest areas and carried out a pixel-based change detection analysis to differentiate temporal and spatial changes.Throughout the study period of 50 years,forest cover has evolved dynamically within the boundaries of the protected areas of Mount Elgon.A significant decline was observed in both Mount Elgon National Park with a loss of-5.98%(-46.83km²)and Mount Elgon Biosphere Reserve with a loss of-14.96%(-134.33km²).Our results showcase a cycle of deforestation and afforestation that could be tied to a series of development initiatives,re-demarcation of boundaries,changes in management and recurring evictions.Overall,the results lead to the conclusion that the lack of sustainable and efficient management and funding has fostered the rate of deforestation and accelerated ecological degradation in the region,but that existing problems are also rooted in the land tenure history of the region.We recommend the proper implementation of participatory and long-term management approaches on the ground and to address the land rights issue to contribute to both socioeconomic wellbeing and sustainable conservation outcomes.
基金Supported by the National Natural Science Foundation of China(12272248)。
文摘The method of integrating factors is used to study the conservation laws of the Herglotz type Birkhoffian systems in this paper.Firstly,the definition of the integrating factors of the Herglotz type Birkhoffian systems is given.Secondly,the relationship between the integrating factors and conservation laws is studied,and the conservation theorems of Herglotz type Birkhoff's equations and their inverse theorems are established.Thirdly,two types of generalized Killing equations for calculating integrating factors are given.Finally,as an example,a linear damped oscillator is taken.This example can be transformed into a Herglotz type Birkhoffian system.The resulting conservation theorems are used to find the conserved quantities for this example.
文摘In this paper,a variable-coefficient modified Kadomtsev-Petviashvili(vcm KP)system is investigated by modeling the propagation of electromagnetic waves in an isotropic charge-free infinite ferromagnetic thin film and nonlinear waves in plasma physics and electrodynamics.Painlevéanalysis is given out,and an auto-B?cklund transformation is constructed via the truncated Painlevéexpansion.Based on the auto-B?cklund transformation,analytic solutions are given,including the solitonic,periodic and rational solutions.Using the Lie symmetry approach,infinitesimal generators and symmetry groups are presented.With the Lagrangian,the vcm KP equation is shown to be nonlinearly self-adjoint.Moreover,conservation laws for the vcm KP equation are derived by means of a general conservation theorem.Besides,the physical characteristics of the influences of the coefficient parameters on the solutions are discussed graphically.Those solutions have comprehensive implications for the propagation of solitary waves in nonuniform backgrounds.
文摘Traditional agricultural irrigation systems waste significant amounts of water and energy due to inefficient scheduling and the absence of real-time monitoring capabilities.This research developed a comprehensive IoT-based smart irrigation control systemto optimize water and energy management in agricultural greenhouses while enhancing crop productivity.The system employs a sophisticated four-layer Internet ofThings(IoT)architecture based on an ESP32 microcontroller,integrated with multiple environmental sensors,including soil moisture,temperature,humidity,and light intensity sensors,for comprehensive environmental monitoring.The system utilizes the Message Queuing Telemetry Transport(MQTT)communication protocol for reliable data transmission and incorporates a Random Forest machine learning algorithm for automated irrigation decision-making processes.The Random Forest model achieved exceptional performance with 99.3%overall accuracy,demonstrating high model reliability.Six operational modules were developed and implemented with three distinct control methods:manual operation,condition-based automatic control,and AI-driven intelligent control systems.A comprehensive one-month comparative analysis demonstrated remarkable improvements across multiple performance metrics:a 50%reduction in both water consumption(from 140 to 70 L/day)and energy usage(from 7.00 to 3.50 kWh/day),a substantial 130%increase in water use efficiency,and a significant 50%decrease in CO_(2) emissions.Furthermore,detailed factor importance analysis revealed soil moisture as the primary decision factor(38.6%),followed by temporal factors(20.3%)and light intensity(18.4%).The system demonstrates exceptional potential for annual energy conservation of 1277.5 kWh and CO_(2) emission reduction of 638.75 kg,contributing substantially to sustainable development goals and advancing smart agriculture technologies.
文摘Water scarcity poses a significant challenge globally,with South Africa exemplifying the severe socio-economic and environmental impacts of limited water access.Despite advances in modern water management systems,the integration of indigenous knowledge(IK)into formal frameworks remains underutilized.This study systematically reviews the role of indigenous water conservation practices in South Africa,analyzing over 50 high-quality sources using the PRISMA methodology.The findings highlight the effectiveness of IK in addressing water scarcity through techniques such as rainwater harvesting,terracing,and wetland management,which are low-cost,environmentally sustainable,and deeply rooted in cultural practices.Indigenous methods also enhance climate resilience by enabling communities to adapt to droughts and floods through practices such as weather prediction and adaptive farming techniques.Furthermore,these practices foster social inclusivity and community empowerment,ensuring equitable water access and intergenerational knowledge transfer.The study underscores the potential of integrating IK with modern water technologies to create holistic solutions that are scalable,sustainable,and aligned with South Africa’s goal of achieving water security by 2030.Policy recommendations emphasize the need for institutional support,data collection,and financial incentives to sustain and mainstream indigenous approaches.By bridging the gap between traditional and contemporary systems,this research provides a roadmap for leveraging diverse knowledge systems to address water scarcity and build resilient communities.
文摘This research paper addresses,from an ecogeographic perspective within a localised context,a new concept of nature conservation within modern farming systems:the direct seeding technique based on the principles of the Conservation Agriculture System(CAS).The adoption of CAS aims to increase soil fertility,promote biodiversity,and sustain production,making it one of the most effective adaptation solutions available to address the challenges of climate change.CAS is defined as a farming system based on three key principles:minimal soil disturbance(reduced or zero tillage),maintaining a permanent soil cover(with residues from previous crops),and adopting crop rotation(diversifying crops rather than limiting them to a single type in consecutive seasons).However,there is limited research and a lack of scientific studies on the implementation of conservation agriculture in developing nations such as Morocco,particularly in the Had Kourt region.This study aims to assess the feasibility of CAS compared to traditional agricultural systems by surveying the opinions of farmers who have experience with both systems and comparing the outcomes of their practices based on simple indicators as an initial stage,with further analysis of additional indicators planned through subsequent scientific investigations.The sampling method used in this study is non-discriminatory,as semi-structured interviews were conducted with a group of farmers to gather their opinions on CAS.The adoption of conservation agriculture has been linked to prior knowledge of the system,acquired through training and fieldwork via application platforms,which remain limited in scope.
