Characteristic analysis of 5D symmetric Hamiltonian conservative hyperchaotic system with hidden multiple stability

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.

Corrigendum to “The transition from conservative to dissipative flows in class-B laser model with fold-Hopf bifurcation andcoexisting attractors”

Recently, we received a letter from Prof. G. L. Oppo, which indicated that he had doubts about the transformation of the system in the article Chin. Phys. B 31 060503 (2022) and gave other considerations. After inspection, we found that there was a clerical error in the article. Based on this, we have made corrections and supplements to the original article.

A High-Order Conservative Semi-Lagrangian Solver for 3D Free Surface Flows with Sediment Transport on Voronoi Meshes

In this paper,we present a conservative semi-Lagrangian scheme designed for the numeri-cal solution of 3D hydrostatic free surface flows involving sediment transport on unstruc-tured Voronoi meshes.A high-order reconstruction procedure is employed for obtaining a piecewise polynomial representation of the velocity field and sediment concentration within each control volume.This is subsequently exploited for the numerical integration of the Lagrangian trajectories needed for the discretization of the nonlinear convective and viscous terms.The presented method is fully conservative by construction,since the transported quantity or the vector field is integrated for each cell over the deformed vol-ume obtained at the foot of the characteristics that arises from all the vertexes defining the computational element.The semi-Lagrangian approach allows the numerical scheme to be unconditionally stable for what concerns the advection part of the governing equations.Furthermore,a semi-implicit discretization permits to relax the time step restriction due to the acoustic impedance,hence yielding a stability condition which depends only on the explicit discretization of the viscous terms.A decoupled approach is then employed for the hydrostatic fluid solver and the transport of suspended sediment,which is assumed to be passive.The accuracy and the robustness of the resulting conservative semi-Lagrangian scheme are assessed through a suite of test cases and compared against the analytical solu-tion whenever is known.The new numerical scheme can reach up to fourth order of accu-racy on general orthogonal meshes composed by Voronoi polygons.

Conservative management of multi-trauma induced peritonitis:Experience,outcomes,and indications

BACKGROUND The concept of mandatory laparotomy in treating traumatic peritonitis has been increasingly questioned recently.AIM To summarize and share the experience of conservative treatment of patients with multi-trauma induced peritonitis.METHODS A retrospective review was performed on patients with multiple injury induced traumatic peritonitis.RESULTS A total of 184 patients with multiple injury induced traumatic peritonitis were reviewed.46 of them underwent conservative treatment.None of the 46 patients with conservative treatment switched to surgical treatment,and all of them were cured and discharged after successful conservative treatment.No significant abnormal findings were observed at regular follow-up after discharge.CONCLUSION Conservative management is safe,effective,feasible,and beneficial in hemodynamically stable patients with traumatic peritonitis if there is no definite evidence of severe abdominal visceral organ injury.

Conservative Treatment of Breast Cancer and Oncoplasty at the Teaching Hospital Mother and Child of Jeanne Ebori Foundation in Libreville (Gabon)

Introduction: Breast cancer is currently the most common malignant tumour in women worldwide. Objective: To evaluate conservative treatment of breast cancer and oncoplasty at the teaching hospital Mother and Child of Jeanne Ebori Foundation (CHUMEFJE). Patients and methods: This is an observational, descriptive study, which took place from August 2019 to December 2021 at CHUMEFJE. Data were collected using patients’ medical records, and operative and pathological anatomy reports. Results: Conservative treatment and oncoplasty were performed in 12 (34.2%) patients. Of these patients, 8 (66.7%) benefited from an external technique and 2 (16.7%) from a pamectomy. Post-operative complications were dominated by lymphocele in 5 (41.6%) patients. Ten (83.3%) patients were satisfied with the post-operative aesthetic result. At the time of updating the records, 1 (8.3%) patient had died and 11 (91.7%) were alive. Conclusion: Conservative treatment and oncoplasty are giving satisfactory results at the CHUMEFJE in Libreville.

Conservative Vector Fields and the Intersect Rule

This paper covers the concept of a conservative vector field, and its application in vector physics and Newtonian mechanics. Conservative vector fields are defined as the gradient of a scalar-valued potential function. Gradient fields are irrotational, as in the curl in all conservative vector fields is zero, by Clairaut’s Theorem. Additionally, line integrals in conservative vector fields are path-independent, and line integrals over closed paths are always equal to zero, properties proved by the Gradient Theorem of multivariable calculus. Gradient fields represent conservative forces, and the associated potential function is analogous to potential energy associated with said conservative forces. The Intersect Rule provides a new, unique shortcut for determining if a vector field is conservative and deriving potential functions, by treating the indefinite integral as a set of infinitely many functions which satisfy the integral.

Acupuncture therapies in combination with conservative treatments for postoperative ileus:a systematic review and network meta-analysis

Background:Although acupuncture therapies have been widely used in combination with conservative treatments(CT)for postoperative ileus(POI),evidence of their safety and efficacy remains scarce.To evaluate and rank the efficacy of different acupuncture therapies combined with CT for POI.Methods:A comprehensive search was carried out in several databases(Embase,PubMed,Cochrane Library,Chinese National Knowledge Infrastructure,Wanfang Data,VIP Chinese Science and Technology Periodical Database and China Biology Medicine disc)for relevant randomized controlled trials(RCTs)investigating different acupuncture therapies for POI from inception to February 17,2023.The Cochrane risk of bias tool was used to determine the risks of bias of the included RCTs.The primary outcomes included the time to first defecation,time to first flatus,and time to first bowel movement;and the secondary outcome was the response rate.Pairwise meta-analysis was performed by Review Manager 5.3 software,and network meta-analysis was carried out by Stata v.15.0 software.The cumulative ranking curve was obtained with Stata v.15.0 and was utilized to rank the included treatments.Results:29 studies with 2,600 participants were included in this systematic review.This meta-analysis demonstrated that all acupuncture therapies combined with CT were superior to conservative treatments alone in time to first defecation,time to first flatus,time to first bowel movement,and response rate.Among 10 evaluated methods,auricular needle with CT was the most effective treatment to reduce the time to first defecation.Furthermore,moxibustion with CT was the most effective in reducing the time to first flatus,and warm needling with CT most markedly reduced the time to first bowel movement among 9 interventions.Moreover,manual acupuncture with CT showed the largest improvement in response rate.Conclusion:This meta-analysis revealed that all acupuncture therapies are effective and safe for POI,with warm needling+CT being the most effective way to relieve symptoms.These results indicated that acupuncture therapies combined with CT should be considered for POI patients.However,most of the included trials were ranked as moderate quality,and further large-scale,high-quality RCTs are required to confirm the optimal interventions for POI patients.

Construction of Conservative Numerical Fluxes for the Entropy Split Method

The entropy split method is based on the physical entropies of the thermally perfect gas Euler equations.The Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in J Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et al.in J Comp Phys 162:33-81,2000).Sj?green and Yee(J Sci Comput)recently proved that the entropy split method is entropy conservative and stable.Stand-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy framework.The current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux derivatives.Due to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split method.However,the Tadmor entropy conservative(EC)method(Tadmor in Acta Numerica 12:451-512,2003)of the same order requires more operations count than the new construction.Since the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et al.in J Comput Phys 150:199-238,1999,J Comp Phys 162:3381,2000;Yee and Sj?green in J Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow Speeds.Proceedings of the ICOSAHOM09,June 22-26,Trondheim,Norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock waves.Long-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches.

Invasive versus conservative strategy in consecutive patients aged 80 years or older with non-ST-segment elevation myocardial infarction: a retrospective study in China

Objective To investigate whether the very elderly patients with non-ST-segment elevation myocardial infarction (NSTEMI) will benefit from an invasive strategy versus a conservative strategy. Methods 190 consecutive patients aged 80 years or older with NSTEMI were included in the retrospective study from September 2014 to August 2017, of which 69 patients received conservative strategy and 121 patients received invasive strategy. The primary outcome was death. Multivariate Cox regression models were used to assess the statistical association between strategies and mortality. The survival probability was further analyzed. Results The primary outcome occurred in 17.4% patients in the invasive group and in 42.0% patients in the conservative group (P = 0.0002). The readmission rate in the invasive group (14.9%) was higher than that in the conservative group (7.2%). Creatinine level (OR = 1.01, 95% CI: 0.10–1.03, P = 0.05) and use of diuretic (OR = 3.65, 95% CI: 1.56–8.53, P = 0.003) were independent influential factors for invasive strategy. HRs for multivariate Cox regression models were 3.45 (95% CI: 1.77–6.75, P = 0.0003), 3.02 (95% CI: 1.52–6.01, P = 0.0017), 2.93 (95% CI: 1. 46–5.86, P = 0.0024) and 2.47 (95% CI: 1.20–5.07, P = 0.0137). Compared with the patients received invasive strategy, the conservative group had remarkably reduced survival probability with time since treatment (P < 0.001). Conclusions An invasive strategy is superior to a conservative strategy in reducing mortality of patients aged 80 years or older with NSTEMI. Our results suggest that an invasive strategy is more suitable for the very elderly patients with NSTEMI in China.

Medium-term efficacy of arthroscopic debridement vs conservative treatment for knee osteoarthritis of Kellgren-Lawrence grades I-III

BACKGROUND Arthroscopic debridement is a mature treatment for knee osteoarthritis(KOA).Due to the differences in the research subjects,methods,and efficacy evaluation indexes,there are great differences in the surgical efficacy reported in the literature.AIM To compare the medium-term efficacy of arthroscopic debridement and conservative treatment for KOA of Kellgren-Lawrence grades I-III.METHODS Patients with KOA of Kellgren-Lawrence grades I-III who were admitted to the orthopedic clinic of our hospital from July 2018 to December 2018 and agreed to undergo arthroscopic surgery were included in an arthroscopic debridement group,and those who refused surgical treatment were included in a conservative treatment group.Gender,age,body mass index(BMI),side of KOA,American hospital for special surgery knee score(HSS score)before treatment,visual analogue scale(VAS)score during walking and rest before treatment,conservative treatment content,and surgical procedure were recorded.Outpatient visits were conducted at the 1st,3rd,6th,12th,and 24th mo after treatment in the two groups.The changes of HSS score and VAS score in each group before and after treatment were statistically analyzed,and the differences of HSS score and VAS score in different treatment stages between the two groups were also compared.RESULTS In the conservative treatment group,there were 80 patients with complete followup data,including 20 males and 60 females,aged 58.75±14.66 years old.And in the knee arthroscopic debridement group,there were 98 patients with complete follow-up data,including 24 males and 74 females,aged 59.27±14.48 years old.There was no statistically significant difference in the general data(gender,age,BMI,side of KOA,Kellgren-Lawrence grade distribution,HSS score,and VAS score)between the two groups before treatment.The HSS scores of the conservative treatment group at the 1st,3rd,6th,12th,and 24th mo after treatment were significantly higher than that before treatment(P<0.05).There was no statistical difference in HSS score of the conservative treatment group among the 1st,3rd,6th,12th,and 24th mo(P>0.05).The HSS score of the knee arthroscopic debridement group at the 1st mo after surgery was significantly higher than that before surgery(P<0.05).HSS scores of the knee arthroscopic debridement group at the 3rd,6th,12th,and 24th mo were significantly higher than those before surgery and at the 1st mo after surgery(P<0.05).There were no statistically significant differences in HSS scores at the 3rd,6th,12th,and 24th mo after surgery(P>0.05).HSS scores at the 3rd,6th,12th,and 24th mo were significantly higher in the arthroscopic debridement group than in the conservative treatment group(P<0.05).There was no statistical difference in HSS scores between the two groups before treatment and at the 1st mo of follow-up(P>0.05).VAS scores during walking and rest were significantly decreased in both groups,and the VAS score during rest was significantly lower in the arthroscopic debridement group than in the conservative treatment group,but there was no significant difference in the VAS score during walking between the two groups after treatment.CONCLUSION Compared with conservative treatment,arthroscopic debridement can significantly improve the knee resting pain and knee functional status of patients with KOA of Kellgren-Lawrence grades I-III within 2 years after treatment.

Conservative pulp treatment for Oehlers type Ⅲ dens invaginatus: A case report

BACKGROUND Diverse presentations of dens invaginatus (DI) and root canal treatment with an immature open apex often pose challenges to dentists. Adequate treatment planning for DI is the main reason for successful approach, i.e., we should consider the shape and depth of the concave folding, the condition of the original pulp, and the growth stage of the root formation. CASE SUMMARY A 9-year-old girl complained of severe pain of the right maxillary incisor (tooth 12) when chewing for two weeks. Following clinical and radiographic examinations, Oehlers type III DI of tooth 12, with an immature open apical foramen and a symptomatic periapical pathosis, was diagnosed. Cone-beam computed tomography verified the specific spatial and stereoscopic data regarding the communication between the main root canal and pseudo root canal of the involved tooth. After removing the source of infection, a mineral trioxide aggregate was selected to fill and seal the pseudo root canal;additionally, pulp capping of the main canal was performed through the interconnections between the root canals in the middle segment to preserve pulp vitality and enable continual root formation and eventual root apex closure. CONCLUSION We propose to conduct main root canal pulp capping for DI with communication between the main and pseudo root canals.

A CONSERVATIVE DIFFERENCE SCHEME FOR CONSERVATIVE DIFFERENTIAL EQUATION WITH PERIODIC BOUNDARY

The conservative form and singular perturbed ordinary differential equation with periodic boundary value problem were studied, and a conservative difference scheme was constructed. Using the method of decomposing the singular term from its solution and combining an asymptotic expansion of the equation, it is proved that the scheme converges uniformly to the solution of differential equation with order one.

Postpartum pubic symphysis diastasis-conservative and surgical treatment methods, incidence of complications: Two case reports and a review of the literature

BACKGROUND Widening of the pubic joint of more than 10 mm is diagnostic and defined as pubic symphysis diastasis and is considered a complication of vaginal childbirth or pregnancy.As it is a rare pathology(ranging from 1 in 300 to 1 in 30000 pregnancies),no gold standard treatment has been defined.CASE SUMMARY This study examines two cases,a 27-year-old woman(gravida 1,para 1)and a 32-year-old woman(gravida 2,para 2),who presented to the clinic after uneventful vaginal deliveries.A normal pregnancy with no complications was observed in both patients.Severe pain in the pubic region occurred after labour and was accompanied by complicated locomotion.Pubic symphysis diastasis was confirmed radiologically and bed rest with lateral decubitus positioning was recommended.Oral non-steroidal antiinflammatory drugs were administered to relieve pain exacerbations.The symptoms decreased after treatment.Posttreatment magnetic resonance imaging(MRI)in the first case showed a reduction in symphyseal separation with no signs of osteitis.Three years later the symptoms recurred;MRI examination showed no further symphyseal widening or signs of osteitis.A relapse of symphyseal separation was diagnosed and conservative treatment was re-administered resulting in successful recovery.In the second case,pain recurred when the patient conceived for the second time.This time no benefit following conservative treatment was observed.Persistent pain and complicated locomotion led to scoliotic deformation of the lumbar part of the spine and leg length discrepancy,thus surgical treatment was chosen and internal pubic synthesis was performed.CONCLUSION Overall,surgical treatment resulting from insufficient conservative treatment showed a high risk of postoperative complications following the treatment of postpartum pubic symphysis diastasis.

Is breast conservative surgery a reasonable option in multifocal or multicentric tumors?

The incidence of multifocal(MF) and multicentric(MC) carcinomas varies widely among clinical studies,depending on definitions and methods for pathological sampling.Magnetic resonance imaging is increasingly used because it can help identify additional and conventionally occult tumors with high sensitivity.However,false positive lesions might incorrectly influence treatment decisions.Therefore,preoperative biopsies must be performed to avoid unnecessary surgery.Most studies have shown higher lymph node involvement rates in MF/MC tumors than in unifocal tumors.However,the rate of local recurrences is usually low after breast conservative treatment(BCT) of MC/MF tumors.It has been suggested that BCT is a reasonable option for MC/MF tumors in women aged 50-69 years,with small tumors and absence of extensive ductal carcinoma in situ.A metaanalysis showed an apparent decreased overall survival in MC/MF tumors but data are controversial.Surgery should achieve both acceptable cosmetic results and negative margins,which requires thorough preoperative radiological workup and localization of lesions.Boost radiotherapy techniques must be evaluated since double boosts might result in increased toxicity,namely fibrosis.In conclusion,BCT is feasible in selected patients with MC/MF but the choice of surgery must be discussed in a multidisciplinary team comprising at least radiologists,surgeons and radiotherapists.

Conservative treatment of knee osteoarthritis:A review of the literature

Knee osteoarthritis(KOA)is a common chronic debilitating disease with an estimated prevalence of 23.9%in the general adult population.The condition is characterised by joint pain,functional impairment and significant reduction in quality of life.Management for KOA can generally be divided into conservative(non-operative)and surgical(operative)measures.Conservative management broadly compromises pharmacological and non-pharmacological options and is conventionally the first line treatment to avoid or delay the need for surgical management.The aim of this study is to provide an overview of the current recommendations,efficacy and safety profile of different conservative treatments through a review of the literature.

Conservative reconstruction using stents as salvage therapy for disruption of esophago-gastric anastomosis

Esophagectomy with extended lymphadenectomy and gastric conduit reconstruction is a radical procedure for the treatment of esophageal cancer that is associated with a high morbidity rate.Gastric conduit necrosis is a fatal complication that occurs in 2%of patients.Conventionally,two-stage salvage surgery consisting of removal of the necrotic gastric conduit followed by reconstruction has been performed;however,this procedure has a high morbidity rate.We describe a61-year-old man who underwent minimally invasive esophagectomy complicated by slowly progressive gastric conduit necrosis associated with complete neck drainage and a stable overall condition.There was a 2 cm gap in the anastomosis.Because there was no evidence of residual gastric conduit necrosis,a removable,covered self-expanding metal stent(SEMS)was inserted to bridge the anastomosis.The stent was fixed to the patient's ear with silk thread through the lasso on its proximal end to prevent migration.Eight weeks after insertion,the stent was removed easily without any associated complications.The anastomotic defect was completely bridged with granulation tissue,showing progressive epithelialization without leakage or stenosis.The patient was discharged home in good general health.This is the first report of the successful conservative management of esophago-gastric conduit anastomosis disruption with SEMS placement.

Direct simulation of MHD flows in dual-coolant liquid metal fusion blanket using a consistent and conservative scheme

Direct simulation of 3-D MHD(magnetohydrodynamics) flows in liquid metal fusion blanket with flow channel insert(FCI) has been conducted.Two kinds of pressure equilibrium slot (PES) in FCI,which are used to balance the pressure difference between the inside and outside of FCI,are considered with a slot in Hartmann wall or a slot in side wall,respectively.The velocity and pressure distribution of FCI made of SiC/SiC_f are numerically studied to illustrate the 3-D MHD flow effects,which clearly show that t...

CONSERVATIVE ESTIMATING FUNCTION IN THE NONLINEAR REGRESSION MODEL WITH AGGREGATED DATA

The purpose of this paper is to study the theory of conservative estimating functions in nonlinear regression model with aggregated data. In this model, a quasi-score function with aggregated data is defined. When this function happens to be conservative, it is projection of the true score function onto a class of estimation functions. By constructing, the potential function for the projected score with aggregated data is obtained, which have some properties of log-likelihood function.

Conservative approach to the acute management of a large mesenteric cyst

Mesenteric cysts are rare, benign gastrointestinal cystic lesions, which are often non-troublesome and present as an incidental radiological finding. However, surgery is often performed in the acute setting to remove lesions that are symptomatic. This report highlights the case of a large, symptomatic mesenteric cyst managed successfully with initial conservative measures followed by planned elective surgery. A 44-year-old female presented with a four-day history of generalised abdominal pain associated with distension, fever, diarrhoea and vomiting. Computer tomography revealed a large(21.7 cm × 11.8 cm × 14 cm) mesenteric cyst within the left abdomen cavity. She was admitted and treated conservatively with intravenous fluids and antibiotics for four days, which lead to complete symptom resolution. Follow-up at intervals of one and three months revealed no return of symptoms. An elective laparotomy and excision of the mesenteric cyst was then scheduled and performed safely at nine months after the initial presentation. Compared to acute surgery, acute conservative management followed by planned elective resection of a symptomatic mesenteric cyst may prove safer. The withholding of an immediate operation may potentially avoid unnecessary operative risk and should be considered in patients without obstructive and peritonitic symptoms. Our case demonstrated the safe use of initial conservative management followed by planned elective surgery of a mesenteric cyst found in the acute setting, which was symptomatic but was not obstructive or causing peritonitic symptoms.

Conservative management of cervical pregnancy with intramuscular administration of methotrexate and KCl injection: Case report and review of the literature

We report the case of a cervical pregnancy successfully treated with intramuscular injection of methotrexate(MTX) and intramniotic administration of potassium chloride. A 41-year-old woman was admitted to our Department with the suspicion of ectopic pregnancy. Transvaginal ultrasound revealed empty endometrialcavity, gestational sac within the cervical canal and embryonic echo measuring crown rump length 1.5 mm. Serum beta human chorionic gonadotropine(β-HCG) was measured 28590 IU/L. No cardiac activity was detected. The diagnosis of a cervical pregnancy was made. Patient was treated with intramuscular administration of methotrexate(50 mg/m2) in combination with ultrasoundguided intramniotic injection of KCl(2 meq/mL). Gradual decrease of β-HCG levels as well as ultrasound observation of collapsed gestational sac was observed. No curettage was necessitated. Patient was discharged on day 10 th and was set in follow-up on a weekly basis. β-HCG values were measured < 10 IU/L on 56 th day after MTX administration. Intramuscular administration of MTX may be effective in treatment of cervical pregnancy without additional interventional measures.