Incidence,Risk Factors,and Prognosis of Patients with Hepatocellular Carcinoma and Brain Metastases

Objective Brain metastases significantly impact the clinical course of patients with hepatocellular carcinoma(HCC).This study aimed to examine the age-related incidence,demographics,and survival of patients with HCC and brain metastases.Methods Data of HCC patients from 2010 to 2015 in the Surveillance,Epidemiology,and End Results(SEER)Registry were screened for the presence of brain metastases.They were stratified by age and ethnicity.Multivariable logistic and Cox regression analyses were used to identify factors associated with brain metastases and those with overall survival(OS)and liver cancer-specific survival(CSS),respectively.Results A total of 141 HCC patients presenting with brain metastases were identified,accounting for 0.35% of all HCC patients and 2.37% of patients with metastatic disease.Among all HCC patients,the incidence rate was the highest among patients aged 30-49 years old(0.47%).Ethnicity was not associated with the presence of brain metastases at the time of HCC diagnosis.However,African-American patients presented with a significantly lower disease-specific survival[median time:1 month;interquartile range(IQR):0-3.0 months].Initial lung or bone metastasis was independently associated with an increased risk of the presence of brain metastases[odds ratio(OR):12.62,95% confidence interval(CI):8.40-18.97]but was not associated with a worse OS or CSS among those with brain metastases.Conclusion This study identified the age-related incidence and risk factors of brain metastases in HCC patients.These results may contribute to the consideration of brain screening among patients with initial metastatic HCC with lung or bone metastases,and influence the counseling of this patient population regarding their prognosis.

Influence of Temperature and Humidity on the Incidence of Pulmonary Tuberculosis in Hainan,China,2004-2018

According to the World Health Organization’s Global Tuberculosis Report 2023,there were 10.6 million cases of tuberculosis(TB)worldwide in 2022,an increase of 2.8%over 2021,and 1.3 million people had already died of the disease.The report also indicated that approximately 748,000 new cases occurred in China in 2022,accounting for 7.1%of the global total,with an incidence of 52/100,000.

Effective transmittance of Fabry–Perot cavity under non-parallel beam incidence

The Fabry–Perot(FP) resonant cavity is widely used in laser and spectroscopic measurements due to its unique interference transfer function(ITF). In the ideal case of parallel incident light, the ITF of the FP resonant cavity can be expressed by the Airy function. However, in reality, it is difficult to achieve perfect parallelism with collimated beams. In this article, a theoretical model is established for non-parallel light incidence, which assumes that the non-parallel incident light is a cone-shaped beam, and the cone angle is used to quantify the non-parallelism of the beam. The transmittance function of the FP resonant cavity under non-parallel light incidence is derived. The accuracy of the model is experimentally verified. Based on this model, the effects of divergence angle, tilt angle and FP cavity parameters(reflectivity, cavity length)on the ITF are studied. The reasons for the decrease in peak value, broadening and asymmetry of the interference peak under non-parallel light incidence are explained. It is suggested that a fine balance between the interference peak and the collimation effect of the incident light should be considered in the design and application of FP resonant cavities, especially for tilted applications such as angle-scanned spectroscopy. The research results of this article have certain significance for the design and application of FP resonant cavities.

A nonlocal dispersal and time delayed HIV infection model with general incidences

Biologically,because of the impact of reproduction period and nonlocal dispersal of HIV-infected cells,time delay and spatial heterogeneity should be considered.In this paper,we establish an HIV infection model with nonlocal dispersal and infection age.Moreover,applying the theory of Fourier transformation and von Foerster rule,we transform the model to an integrodifferential equation with nonlocal time delay and dispersal.The well-posedness,positivity,and boundedness of the solution for the model are studied.

An improved positioning model of deep-seafloor datum point at large incidence angle

The inhomogeneous sound speed in seawater causes refraction of sound waves,and the elimination of the refraction effect is essential to the accuracy of underwater acoustic positioning.The raytracing method is an indispensable tool for effectively handling problems.However,this method has a conflict between localization accuracy and computational quantity.The equivalent sound speed profile(ESSP)method uses a simple sound speed profile(SSP)instead of the actual complex SSP,which can improve positioning precision but with residual error.The residual error is especially non-negligible in deep water and at large beam incidence angles.By analyzing the residual error of the ESSP method through a simulation,an empirical formula of error is presented.The data collected in the sailing circle mode(large incidence angle)of the South China Sea are used for verification.The experiments show that compared to the ESSP method,the improved algorithm has higher positioning precision and is more efficient than the ray-tracing method.

Influences of Earth Incidence Angle on FY-3/MWRI SST Retrieval and Evaluation of Reprocessed SST

Sea surface temperature(SST)is a crucial physical parameter in meteorology and oceanography.This study demonstrates that the influence of earth incidence angle(EIA)on the SST retrieved from the microwave radiation imager(MWRI)onboard FengYun-3(FY-3)meteorological satellites should not be ignored.Compared with algorithms that do not consider the influence of EIA in the regression,those that integrate the EIA into the regression can enhance the accuracy of SST retrievals.Subsequently,based on the recalibrated Level 1B data from the FY-3/MWRI,a long-term SST dataset was reprocessed by employing the algorithm that integrates the EIA into the regression.The reprocessed SST data,including FY-3B/MWRI SST during 2010-2019,FY-3C/MWRI SST during 2013-2019,and FY-3D/MWRI SST during 2018-2020,were compared with the in-situ SST and the SST dataset from the Operational Sea Surface Temperature and Ice Analysis(OSTIA).The results show that the FY-3/MWRI SST data were consistent with both the in-situ SST and the OSTIA SST dataset.Compared with the Copernicus Climate Change Service V2.0 SST,the absolute deviation of the reprocessed SST,with a quality flag of 50,was less than 1.5℃.The root mean square errors of the FY-3/MWRI orbital,daily,and monthly SSTs,with a quality flag of 50,were approximately 0.82℃,0.69℃,and 0.37℃,respectively.The primary discrepancies between the FY-3/MWRI SST and the OSTIA SST were found mainly in the regions of the western boundary current and the Antarctic Circumpolar Current.Overall,this reprocessed SST product is recommended for El Niño and La Niña events monitoring.

Comprehensive Analysis of Cancer Incidence and Mortality Trends in Costa Rica: Implications for Public Health

This commentary delves into the evolving landscape of cancer incidence and mortality in Costa Rica, presenting a comprehensive analysis of the data. Key findings reveal a concerning upward trajectory in cancer incidence rates, placing Costa Rica at the forefront within Central America. While prostate cancer and breast cancer dominate, disparities emerge when scrutinizing gender-specific trends. Notably, stomach and cervical cancers show declines, potentially attributed to targeted interventions. However, colorectal and liver cancers witness mortality increases, necessitating strategic responses. Geographical disparities persist across provinces, highlighting the need for equitable healthcare access. In conclusion, this commentary underscores the urgency of addressing the burgeoning cancer burden in Costa Rica, calling for evidence-based interventions and collaborative efforts on a global scale.

Knee Arthroplasty Incidence Rate vs. Revision of Knee Arthroplasty and Its Associated Comorbidities in Colombia

Introduction: Total knee arthroplasty (TKA) has been established as a transformative solution in the treatment of advanced degenerative diseases of the knee, such as osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis. In this sense, TKA surgery, which seeks to replace the damaged joint with prosthetic components, has proven to be highly effective in relieving pain, improving joint function, and, ultimately, significantly increasing patients’ quality of life. The present study describes the TKA and revision knee arthroplasty (RKA) rates and, identifies the associated co morbidities in the Colombian context. Methods: A retrospective cohort study was carried out. It describes demographic and clinical characteristics between two groups of patients, TKA or RKA, and its association with mortality at 30 days, 90 days, or one year after the intervention. Results: The incidence rate of the population undergoing TKA was approximately 11.71 cases per 100,000 inhabitants. Furthermore, the incidence rate for revision knee arthroplasty (RKA) procedures in the same period was around 0.96 per 100,000 inhabitants. In both groups at 30 days postoperatively, a total mortality rate of 0.09%was recorded. When the follow-up was extended to 90 days, it increased to 0.15%;at one year postoperatively, it rose to 0.88%. Conclusion: Mortality after surgery was low in Colombia in 2019. Although RKA is a beneficial procedure, in certain circumstances, it was noted that it carries a higher risk compared to primary TKA. Our results emphasize the importance of careful evaluation of co morbidities and risk factors in patients undergoing these surgical procedures. The application of quality-of-life questionnaires should be considered in future studies on effectiveness and mortality for TKA and RKA in our country.

Incidence and Survivability of Acute Lymphocytic Leukemia Patients in the United States: Analysis of SEER Data Set from 2000-2019

The main goal of this research is to assess the impact of race, age at diagnosis, sex, and phenotype on the incidence and survivability of acute lymphocytic leukemia (ALL) among patients in the United States. By taking these factors into account, the study aims to explore how existing cancer registry data can aid in the early detection and effective treatment of ALL in patients. Our hypothesis was that statistically significant correlations exist between race, age at which patients were diagnosed, sex, and phenotype of the ALL patients, and their rate of incidence and survivability data were evaluated using SEER*Stat statistical software from National Cancer Institute. Analysis of the incidence data revealed that a higher prevalence of ALL was among the Caucasian population. The majority of ALL cases (59%) occurred in patients aged between 0 to 19 years at the time of diagnosis, and 56% of the affected individuals were male. The B-cell phenotype was predominantly associated with ALL cases (73%). When analyzing survivability data, it was observed that the 5-year survival rates slightly exceeded the 10-year survival rates for the respective demographics. Survivability rates of African Americans patients were the lowest compared to Caucasian, Asian, Pacific Islanders, Alaskan Native, Native Americans and others. Survivability rates progressively decreased for older patients. Moreover, this study investigated the typical treatment methods applied to ALL patients, mainly comprising chemotherapy, with occasional supplementation of radiation therapy as required. The study demonstrated the considerable efficacy of chemotherapy in enhancing patients’ chances of survival, while those who remained untreated faced a less favorable prognosis from the disease. Although a significant amount of data and information exists, this study can help doctors in the future by diagnosing patients with certain characteristics. It will further assist the health care professionals in screening potential patients and early detection of cases. This could also save the lives of elderly patients who have a higher mortality rate from this disease.

Incidence and Management of Early Postoperative Hypoxemia after Abdominal Surgery at Teaching Hospital

Background: Oxygen saturation refers to the quantity of oxygenated hemoglobin in the blood, that is to say the level of oxygen measurable in the red blood cells when they have passed through the lungs. The aim of this study was to describe the management of early postoperative hypoxemia after abdominal surgery at the Yaounde General Hospital (YGH). Method: This is a quantitative, observational study, with a descriptive aim, which took place in the anesthesiology department of the YGH, over a period of 2 months from August 1st to October 1st, 2023. The study included all the patients ≥18 years, of both sexes who had abdominal surgery under general anesthesia and were willing to participate during the time of data collection. The variables studied were the sociodemographic and clinical characteristics, risk factors for oxygen desaturation, postoperative variations in SPO2 and therapeutic tools. Results: We collected 30 patients among whom 11 presented with early postoperative hypoxemia i.e. a frequency of 36.7%. The age of the patients ranged from 18 to 63 years and the mean was 42.47 ± 13.5 years on average. The sex ratio was 0.5. Hysterectomy was the most commonly performed surgery (23.3%). The most common comorbidity was high blood pressure (30%). Half of the patients had midline incision. Supra-umbilical surgery predominated (56.7%), intraoperative blood loss ≥500 ml in 46.7% of cases. Upper abdominal surgery with, subcostal incision and blood loss ≥500 ml are statistically significant risk factors for the occurrence of early postoperative hypoxemia (P Conclusion: Hypoxemia is the result of impaired respiratory function favored by the conditions encountered during the early postoperative period.

Incidences and Risk Factors for Surgical Site Infections in Koutiala, Mali

Purpose: This paper aims to assess the incidences and risk factors for surgical site (ISO) infections in the general surgery department of the Koutiala District Hospital. Patients and Methods: This was a prospective and descriptive study from August 1, 2017 to October 31, 2020 involving all patients who underwent laparotomy in the general surgery department of the Koutiala District Hospital. Patients who were not operated on and who did not have a laparotomy were not included. Age, sex, frequency, patient history, National Nosocomial Infections Surveillance (NNIS) index, time to occur, bacteriological test results and course of infection were analyzed. Results: Fifty patients were registered. The average age was 34.2 ± 21.2 years old. Eleven patients were 60 years old or older. The hospital incidence rate was 4.3% and the community incidence rate was 6.1 cases per 100,000 population. The concept of smoking was noted in 15 patients. Patients were operated on in emergency 84% of cases. Peritonitis was the most common initial lesion with 32% of cases. Our patients had an NNIS index greater than 0 in 84% of cases. The time to develop infection from the surgical site was less than 3 days in 8 patients (16% of cases). Depending on the depth of the infection, it was superficial (cutaneous) in 39 patients (78%) and deep (subcutaneous and organic) in 11 patients (22%). Escherichia coli was the most common germ with 72% followed by staphylococcus aureus at 24%. We noted 22% morbidity. The median length of hospitalization was 9 ± 2.2 days. Conclusion: ISO is common in our service. Prevention and mastery require knowledge of risk factors.

Incidence and Management of Occupational Blood Exposure (OBE) among Medical Students at the University of Bangui

Introduction: Like healthcare workers, medical students are also exposed to a risk of accidental contamination during their hospital internships. However, they do not benefit from prevention services in the same way as workers in this sector, although they actively participate in the routine care provided to patients in the various hospital departments. The objective of our study is to determine the incidence of these accidents and their medical and administrative management among these victims (medical students) not classified in the category of workers. Materials and Method: This was a cross-sectional study carried out over three months from January 15 to March 14, 2023. The study population consisted of all medical students at the Faculty of Health Sciences at the University of Bangui. Regularly enrolled students from 2nd to 7th year, on placement in hospitals in the Central African Republic and who gave their informed consent were included. Data were collected through a self-administered questionnaire. Results: A cross-sectional study was carried out among medical students concerning the incidence and management of accidents involving exposure to blood in the Central African Republic. Of the 254 students included, three (9%) had already been correctly vaccinated against the viral hepatitis B virus, 198 (77.9%) reported still having access to personal protective equipment, 133 students (52.4%) reported being victims of OBE in the past 12 months. The main types of OBE were stings (62%), followed by liquid splashes (32%) and cuts (6%). Among the 133 victims, 92.9% carried out immediate hand disinfection or abundant eye washing, 41.9% obtained the serology of the source patient and 37% reported the accident to their supervisor. Conclusion: It is important that students benefit from better prevention and management of these accidents.

Corrective Effect of the Angle of Incidence of the Magnetic Field Intensity on the Performance (Series and Shunt Resistances) of a Bifacial Silicon Solar Cell

This article presents a three-dimensional analysis of the impact of the angle of incidence of the magnetic field intensity on the electrical performance (series resistance, shunt resistance) of a bifacial polycrystalline silicon solar cell. The cell is illuminated simultaneously from both sides. The continuity equation for the excess minority carriers is solved at the emitter and at the depth of the base respectively. The analytical expressions for photocurrent density, photovoltage, series resistance and shunt resistance were deduced. Using these expressions, the values of the series and shunt resistances were extracted for different values of the angle of incidence of the magnetic field intensity. The study shows that as the angle of incidence increases, the slopes of the minority carrier density for the two modes of operation of the solar cell decrease. This is explained by a drop in the accumulation of carriers in the area close to the junction due to the fact that the Lorentz force is unable to drive the carriers towards the lateral surfaces due to the weak action of the magnetic field, which tends to cancel out as the incidence angle increases, and consequently a drop in the open circuit photovoltage. This, in turn, reduces the Lorentz force. These results predict that the p-n junction of the solar cell will not heat up. The study also showed a decrease in series resistance as the incidence angle of the magnetic field intensity increased from 0 rad to π/2 rad and an increase in shunt resistance as the incidence angle increased. His behaviour of the electrical parameters when the angle of incidence of the field from 0 rad to π/2 rad shows that the decreasing magnetic field vector tends to be collinear with the electron trajectory. This allows them to cross the junction and participate in the external current. The best orientation for the Lorentz force is zero, in which case the carriers can move easily towards the junction.

Contribution to the Study of the Incidence of Post-Streptococcal Complications in Republic Central African Republic from 2015 to 2018

Introduction: Acute rheumatic fever (AAR) is a non-suppurative complication of late infection by group A. Infections due to streptococci remain a public health problem in the Central African Republic. The present study aims to determine the incidence rate of AAR cases and its complications. Methodology: This was a retrospective and analytical study over a period of 4 years (from January 2015 to December 2018) at the National Laboratory of Clinical Biology and Public Health (LNBCSP) in Bangui. It focused on samples concerning the diagnosis of AAR and patient files seen in consultation in the capital’s reference health establishments. Laboratory registers and patient consultation files were used to collect data. They were entered into Excel 2010 to be analyzed with Epi Info 7. A univariate analysis by logistic regression, Ficher’s exact test, and chi2 at the 5% threshold (p Results: We analyzed 94 cases meeting Jones’s criteria. The ages of the patients ranged from 18 to 85 years (mean age 52 years and mode 45 years). The incidence rate of AAR for the female sex was higher than that of the male sex during the study period (p > 0.05). It went from 166.6 in 2015 to 200 in 2016 and 2018 cases of AAR per 1000 people per year. The average incidence rate was 296.18 cases of AAR per 1000 people per year. The average incidence rate was 223.5 cases of AAR per 1000 people per year for joint damage. Joint damage represented 80.85% (RR = 0.62;Chi2 = 4.88;95% CI [0.39-0.97];p Conclusion: The study allowed data on the impact rate and complications of the AAR in Bangui. Special attention to data management will help produce a complete result on the problem. Joint complications predominated. Sustaining an effective surveillance system and preventing infection would help reduce the risk of AAR occurrence.

Incidence,prevalence,and comorbidities of chronic pancreatitis:A 7-year population-based study

BACKGROUND Chronic pancreatitis(CP)is a fibroinflammatory syndrome leading to reduced quality of life and shortened life expectancy.Population-based estimates of the incidence,prevalence,and comorbidities of CP in China are scarce.AIM To characterize the incidence,prevalence,and comorbidities of CP in Sichuan Province,China,with population-based data.METHODS Data on CP from 2015 to 2021 were obtained from the Health Information Center of Sichuan Province.During the study period,a total of 38090 individuals were diagnosed with CP in Sichuan Province.The yearly incidence rate and point prevalence rate(December 31,2021)of CP were calculated.The prevalence of comorbid conditions in CP patients was estimated.The annual number of CPrelated hospitalizations,hospital length of stay,and hospitalization costs for CP were evaluated.Yearly incidence rates were standardized for age by the direct method using the permanent population of Sichuan Province in the 2020 census as the standard population.An analysis of variance test for the linearity of scaled variables and the Cochran-Armitage trend test for categorical data were performed to investigate the yearly trends,and a two-sided test with P<0.05 was considered statistically significant.RESULTS The 38090 CP patients comprised 23280 males and 14810 females.The mean age of patients at CP diagnosis was 57.83 years,with male patients(55.87 years)being younger than female patients(60.11 years)(P<0.001).The mean incidence rate of CP during the study period was 6.81 per 100000 person-years,and the incidence of CP increased each year,from 4.03 per 100000 person-years in 2015 to 8.27 per 100000 person-years in 2021(P<0.001).The point prevalence rate of CP in 2021 was 45.52 per 100000 individuals for the total population,with rates of 55.04 per 100000 individuals for men and 35.78 per 100000 individuals for women(P<0.001).Individuals aged 65 years or older had the highest prevalence of CP(113.38 per 100000 individuals)(P<0.001).Diabetes(26.32%)was the most common comorbidity in CP patients.The number of CP-related hospitalizations increased from 3739 in 2015 to 11009 in 2021.The total costs for CP-related hospitalizations for CP patients over the study period were 667.96 million yuan,with an average of 17538 yuan per patient.CONCLUSION The yearly incidence of CP is increasing,and the overall CP hospitalization cost has increased by 1.4 times during the last 7 years,indicating that CP remains a heavy health burden.

Changes in Notified Incidence of Pulmonary Tuberculosis in China,2005–2020

Objective To evaluate the trend of notified incidence of pulmonary tuberculosis(PTB)in China at different periods by population and region and to explore the effect of TB prevention and control in recent years.Methods Using pooled data on TB cases reported by the TB Information Management Reporting System(TBIMS)from 2005 to 2020,we calculated the annual percentage change(APC)using the Joinpoint regression model.Results From 2005 to 2020,a total of 16.2 million cases of PTB were reported in China,with an average notified incidence of 75.5 per 100,000 population.The age standardization rate(ASR)continued to decline from 116.9(/100,000)in 2005 to 47.6(/100,000)in 2020,with an average annual decrease of5.6%[APC=-5.6,95%confidence interval(CI):-7.0 to-4.2].The smallest decline occurred in2011–2018(APC=-3.4,95%CI:-4.6 to-2.3)and the largest decrease in 2018–2020(APC=-9.2,95%CI:-16.4 to-1.3).From 2005 to 2020,the ASR in males(159.8 per 100,000 in 2005,72.0 per 100,000 in2020)was higher than that in females(62.2 per 100,000 in 2005,32.3 per 100,000 in 2020),with an average annual decline of 6.0%for male and 4.9%for female.The average notified incidence was the highest among older adults(65 years and over)(182.3/100,000),with an average annual decline of6.4%;children(0–14 years)were the lowest(4.8/100,000),with an average annual decline of 7.3%,but a significant increase of 3.3%between 2014 and 2020(APC=3.3,95%CI:1.4 to 5.2);middle-aged(35–64years)decreased by 5.8%;and youth(15–34 years)decreased by an average annual rate of 4.2%.The average ASR in rural areas(81.3/100,000)is higher than that in urban areas(76.1/100,000).The average annual decline in rural areas was 4.5%and 6.3%in urban areas.South China had the highest average ASR(103.2/100,000),with an average annual decline of 5.9%,while North China had the lowest(56.5/100,000),with an average annual decline of 5.9%.The average ASR in the southwest was 95.3(/100,000),with the smallest annual decline(APC=-4.5,95%CI:-5.5 to-3.5);the average ASR in the Northwest China was 100.1(/100,000),with the largest annual decline(APC=-6.4,95%CI:-10.0 to-2.7);Central,Northeastern,and Eastern China declined by an average of 5.2%,6.2%,and 6.1%per year,respectively.Conclusions From 2005 to 2020,the notified incidence of PTB in China continued to decline,falling by55%.For high-risk groups such as males,older adults,high-burden areas in South,Southwest,and Northwest China,and rural regions,proactive screening should be strengthened to provide timely and effective anti-TB treatment and patient management services for confirmed cases.There is also a necessity to be vigilant about the upward trend of children in recent years,the specific reasons for which need to be further studied.

Incidence rate of animal bites in southern Iran during 2015-2019 using Cochrane-Armitage trend test

Objective:To investigate the trend of animal bites in southern Iran from 2015 to 2019.Methods:This is a cross-sectional study of patients with animal bites who were referred to the Center for Disease Control in the three cities of Larestan,Evaz,and Khonj in Fars province,southern Iran from 2015 to 2019.The trend of animal bites incidence was analyzed using the Cochran-Armitage trend test.Results:In total,from 2015 to 2019,1944 cases of animal bites were reported.A total of 79.8%of the cases were men.The overall average incidence of animal bites was 142.93 per 100000 people.The incidence of animal bites was significantly increased(Ptrend<0.001).The highest incidence was in November(79.04 per 100000 people)followed by January(76.1 per 100000 people)and February(69.48 per 100000 people);also,the lowest incidence was in August(47.42 per 100000 people)and July(50.0 per 100000 people).Conclusions:The incidence of animal bites has significantly increased.Given the importance of rabies,control and management of animal bites should be emphasized and considered.

Incidence and clinical treatment of hypertriglyceridemic acute pancreatitis:A few issues

Hypertriglyceridemia is a well-recognized etiology of acute pancreatitis,and the incidence of hypertriglyceridemic acute pancreatitis(HTG-AP)has increased in frequency worldwide in response to lifestyle changes.It is crucial to identify hypertriglyceridemia as the cause of pancreatitis and initiate appropriate treatment.Insulin treatment produces effective lowering of triglycerides,but in our opinion,non-diabetic patients with HTG-AP require separate consideration to avoid hypoglycemia.

Wind farm active power dispatching algorithm based on Grey Incidence

This study proposes a wind farm active power dispatching(WFAPD) algorithm based on the grey incidence method, which does not rely on an accurate mathematical model of wind turbines. Based on the wind turbine start-stop data at different wind speeds, the weighting coefficients, which are the participation degrees of a variable speed system and a variable pitch system in power regulation, are obtained using the grey incidence method. The incidence coefficient curve is fitted by the B-spline function at a full range of wind speeds, and the power regulation capacity of all wind turbines is obtained. Finally, the WFAPD algorithm, which is based on the regulating capacity of each wind turbine, is compared with the wind speed weighting power dispatching(WSWPD) algorithm in MATLAB. The simulation results show that the active power fluctuation of the wind farm is smaller, the rotating speed of wind turbines is smoother, and the fatigue load of highspeed turbines is effectively reduced.

Stability and optimal control for delayed rumor-spreading model with nonlinear incidence over heterogeneous networks

On the multilingual online social networks of global information sharing,the wanton spread of rumors has an enormous negative impact on people's lives.Thus,it is essential to explore the rumor-spreading rules in multilingual environment and formulate corresponding control strategies to reduce the harm caused by rumor propagation.In this paper,considering the multilingual environment and intervention mechanism in the rumor-spreading process,an improved ignorants–spreaders-1–spreaders-2–removers(I2SR)rumor-spreading model with time delay and the nonlinear incidence is established in heterogeneous networks.Firstly,based on the mean-field equations corresponding to the model,the basic reproduction number is derived to ensure the existence of rumor-spreading equilibrium.Secondly,by applying Lyapunov stability theory and graph theory,the global stability of rumor-spreading equilibrium is analyzed in detail.In particular,aiming at the lowest control cost,the optimal control scheme is designed to optimize the intervention mechanism,and the optimal control conditions are derived using the Pontryagin's minimum principle.Finally,some illustrative examples are provided to verify the effectiveness of the theoretical results.The results show that optimizing the intervention mechanism can effectively reduce the densities of spreaders-1 and spreaders-2 within the expected time,which provides guiding insights for public opinion managers to control rumors.