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In distance-selected imaging, the contrast of laser images is reduced due to long imaging distances, insufficient laser power, and atmospheric turbulence. An enhancement algorithm based on the EnlightenGAN network is proposed to improve the contrast of laser images. Firstly, the laser images are acquired using a distance selection pass system to establish the laser image dataset and expand the dataset, and the traditional algorithm is used to enhance the images and establish the mapping relationship between low-quality images and high-quality images. The global discriminator based on PatchGAN with the improved VGG model is used to regularize the self-feature retention loss and construct the depth link between the global discriminator and the local discriminator to improve the generalization ability of the model; adjust the attention map to the second layer before the CLB convolution module and also add the residual structure in the second layer CLB to improve the robustness of the model; adopt the idea of gray-scale layering with a low drop and high rise to improve the self regularization mechanism to achieve the enhancement of the key region; finally, use the improved EnlightenGAN to fit the relationship between a low-quality image and high-quality image. Finally, EnlightenGAN is used to fit the relationship between low-quality images and high-quality images, extract laser image features, and enhance low-quality images. The experimental results show that the improved algorithm improves PSNR by 12.3% and 0.7% on average, SSIM by 57% and 10.3% on average, and NIQE by 21% and 13% on average compared to other algorithms and the original EnlightenGAN algorithm, respectively. The algorithm improves the signal-to-noise ratio and contrast of laser images with richer image details. It provides a new idea for pre-processing laser images.

Heterostructures composed of the intrinsic magnetic topological insulator MnBi$_2$Te$_4$ and its non-magnetic counterpart Bi$_2$Te$_3$ host distinct surface band structures depending on the stacking order and exposed termination, allowing fine control of their magnetic, electronic and optical properties. Here, we probe the ultrafast dynamical response of MnBi$_2$Te$_4$ and MnBi$_4$Te$_7$ following near-infrared optical excitation using time- and angle-resolved photoemission spectroscopy. We gain access to the out-of-equilibrium surface electronic structure of both MnBi$_2$Te$_4$ and Bi$_2$Te$_3$ surface terminations of MnBi$_4$Te$_7$, revealing an instantaneous occupation of states that are resonant with the optical excitation in the Bi$_2$Te$_3$ layer followed by carrier extraction into the adjacent MnBi$_2$Te$_4$ layers with a laser fluence-tunable delay of up to 350 fs. The ensuing thermal relaxation processes are driven by in-plane phonon scattering with significantly slower relaxation times in the magnetic MnBi$_2$Te$_4$ septuple layers. The competition of interlayer charge transfer and intralayer phonon scattering establishes MnBi$_2$Te$_4$-based compounds as a platform for controlling ultrafast charge transfer processes in combination with magnetism and topology in van der Waals heterostructures., 17 pages, 4 figures

ObjectivesTo assess the uptake of second-line antihyperglycemic agents among patients with type-2 diabetes mellitus (T2DM) receiving metformin.DesignSerial cross-sectional study (2011-2021).SettingTen US and seven non-US electronic health record and administrative claims databases in the Observational Health Data Sciences and Informatics network.Participants4.8 million patients with T2DM receiving metformin.Main Outcomes MeasuresCalendar-year trends in the proportional initiation of second-line antihyperglycemic agents, glucagon-like peptide-1 receptor agonists (GLP-1 RAs), sodium-glucose cotransporter 2 inhibitors (SGLT2is), dipeptidyl peptidase-4 inhibitors, and sulfonylureas, for each database. We also evaluated the relative drug class-level uptake across cardiovascular risk groups.ResultsWe identified 4.6 million patients with T2DM in US databases, 61,382 from Spain, 32,442 from Germany, 25,173 from the UK, 13,270 from France, 5,580 from Scotland, 4,614 from Hong Kong, and 2,322 from Australia. During 2011-2021, the combined proportional initiation of cardioprotective antihyperglycemic agents, GLP-1 RAs and SGLT2is, increased across all data sources, with the combined initiation of these drugs as second-line agents in 2021 ranging from 35.2% to 68.2% in the US databases, 15.4% in France, 34.7% in Spain, 50.1% in Germany, and 54.8% in Scotland. From 2016 to 2021, in some US and non-US databases, uptake of GLP-1 RAs and SGLT2is increased more significantly among populations without cardiovascular disease compared to those with established cardiovascular disease, without any data source providing evidence of a greater increase in their uptake in the populations with cardiovascular disease.ConclusionsDespite the increase in overall uptake of cardioprotective antihyperglycemic agents as second-line treatment for T2DM, their uptake was lower in patients with cardiovascular disease over the last decade. A strategy to ensure medication use concordant with guideline recommendations is essential to improve outcomes of patients with T2DM.

ImportanceAmid efforts in the United States to promote health equity, there is a need to assess progress in reducing excess deaths and years of potential life lost (YPLL) among Black people compared with White people.ObjectiveTo evaluate trends in excess mortality and YPLL among Black people compared with White people.DesignSerial cross-sectional.SettingNational data from the Centers for Disease Control and Prevention, 1999-2020ParticipantsNon-Hispanic White and non-Hispanic Black peopleExposuresRace as documented in the death certificates.Main outcomes and measuresExcess age-adjusted all-cause and disease-specific mortality rate (per 100,000 individuals) and YPLL among Black people compared with White people.ResultsFrom 1999 to 2020, the total number of excess deaths was 658,356 and 1,154,108 among Black females and males, representing 34,938,070 and 47,005,048 excess YPLL among Black females and males. The excess deaths and YPLL were largest among infants and non-elderly adults. Heart disease had the most excess deaths. From 1999, the age-adjusted excess mortality rate declined at an annual average of -9.0 (95% CI: -10.0, -8.0; PConclusions and relevanceOver a recent 22-year period, Black people in the US lost more than 80 million years of life when compared with White people. After a period of progress, improvements stalled, and most gains were eliminated in 2020.KEY POINTSQuestionHow many excess deaths and years of potential life lost (YPLL) for Black people, compared with White people, occurred in the United States from 1999 through 2020?FindingsBased on Centers for Disease Control and Prevention data, excess deaths and YPLL persisted throughout the period, with initial progress followed by little improvement, and then worsening in 2020 to about 1999 levels. Black people had 1.8 million excess deaths and over 80 million YPLL over the study period.MeaningAfter initial progress, excess mortality and YPLL among Black people stagnated and then worsened, indicating a need for new approaches.

ImportanceAmid efforts in the US to promote health equity, there is a need to assess recent progress in reducing excess deaths and years of potential life lost among the Black population compared with the White population.ObjectiveTo evaluate trends in excess mortality and years of potential life lost among the Black population compared with the White population.Design, setting, and participantsSerial cross-sectional study using US national data from the Centers for Disease Control and Prevention from 1999 through 2020. We included data from non-Hispanic White and non-Hispanic Black populations across all age groups.ExposuresRace as documented in the death certificates.Main outcomes and measuresExcess age-adjusted all-cause mortality, cause-specific mortality, age-specific mortality, and years of potential life lost rates (per 100 000 individuals) among the Black population compared with the White population.ResultsFrom 1999 to 2011, the age-adjusted excess mortality rate declined from 404 to 211 excess deaths per 100 000 individuals among Black males (P for trend P for trend = .98) and increased in 2020 to 395—rates not seen since 2000. Among Black females, the rate declined from 224 excess deaths per 100 000 individuals in 1999 to 87 in 2015 (P for trend P for trend = .71) and in 2020 rates increased to 192—levels not seen since 2005. The trends in rates of excess years of potential life lost followed a similar pattern. From 1999 to 2020, the disproportionately higher mortality rates in Black males and females resulted in 997 623 and 628 464 excess deaths, respectively, representing a loss of more than 80 million years of life. Heart disease had the highest excess mortality rates, and the excess years of potential life lost rates were largest among infants and middle-aged adults.Conclusions and relevanceOver a recent 22-year period, the Black population in the US experienced more than 1.63 million excess deaths and more than 80 million excess years of life lost when compared with the White population. After a period of progress in reducing disparities, improvements stalled, and differences between the Black population and the White population worsened in 2020.

As the global environmental pollution and energy crisis become more serious, lithium-ion batteries (LIB) received an increasing research interest due to their low self-discharge rates, long cycle life, and high power density for the transportation applications. Battery management system (BMS) plays an essential part for the LIB system as it can guarantee an efficient and stable operation through LIB state of charge (SOC) estimation. In this article, a nonlinear observer with terminal voltage feedback injection (VFNO) is designed based on the electrochemical single particle (SP) model to monitor the SOC of LIB. The convergence of the SP-VFNO system in consideration of measurement error is proved in terms of Lyapunov stability theory. The current, the terminal voltage, and the SOC reference value are measured in the battery testing system. Besides, the extended Kalman filter (EKF) based on both the SP model and the second-order resistor-capacitor (SORC) model to estimate SOC is adopted for comparison. The experimental results indicate that the proposed SP-VFNO method has superiority with a faster convergence rate and a higher estimation precision, which can help the accurate SOC estimation for BMS in practical application.

ObjectiveTo evaluate medication guideline adherence among ambulatory patients with markedly elevated blood pressure (BP), overall and by patient characteristics.DesignPopulation-based, retrospective cohort study.SettingYale New Haven Health System.ParticipantsAdult patients aged 18-85 years with markedly elevated BP (defined as two consecutive outpatient visits with systolic BP ≥160 mmHg or diastolic BP ≥100 mmHg) between October 1st, 2015 and December 31st, 2018.Main outcome measuresWe assessed the number and class of antihypertensive drugs (previously taken and newly prescribed) prior to 90 days of the second visit with BP ≥160/100 mmHg. Among patients treated with two-drug class regimens, we assessed the proportion of patients on guideline-recommended two drug classes, overall and stratified by documentation of prior myocardial infarction (MI), diabetes, chronic kidney disease (CKD), and uncomplicated hypertension (i.e., without MI, coronary artery disease, diabetes, CKD, and cerebrovascular disease).ResultsWe identified 16,377 patients with markedly elevated BP. They had a mean age of 65.8 (SD: 14.5) years; 54.0% were female; and 69.4%, 19.6%, and 9.6% were White, Black, and Hispanic, respectively. Prior to 90 days of the second visit, 29.8% had no active antihypertensive drug prescription, 20.0% had one drug class prescribed, and 50.2% had two or more drug classes prescribed. Among patients prescribed one antihypertensive drug class, the most common drug class was angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB), followed by calcium channel blocker (CCB). Among patients prescribed two antihypertensive drug classes, the most common treatment combinations were ACEI or ARB and thiazide diuretic (21.0%), followed by ACEI or ARB and CCB (20.6%). Guideline-recommended two-drug class combination therapy were prescribed in 54.3% of the treated population, with the highest proportion of 67.0% in patients with a prior MI and the lowest proportion of 48.2% among patients with CKD. Older age, lower body mass index, and lower BP were associated with lower prescription of guideline-recommended combination therapy.ConclusionOnly half of patients with markedly elevated BP were prescribed guideline-recommended antihypertensive combination drugs. Major opportunities exist for improving the guideline adherence of antihypertensive drug prescription in this population.What this Paper AddsSection 1: What is already known on this subject?Hypertension affects nearly one in two adults in the United States, of whom 20% have markedly elevated blood pressure (BP; defined as BP ≥160/100 mmHg). People with markedly elevated BP have increased risks of adverse cardiovascular and kidney events. Clinical guidelines recommend prescribing combination therapy with two or more antihypertensive agents for patients with markedly elevated BP.Section 2: What this study addsThis study quantified the real-world medication guideline adherence among ambulatory patients with markedly elevated BP, using electronic health record data from a large health system in the United States. Prior to 90 days of the second visit with BP ≥160/100 mmHg, nearly 30% of patients had no active antihypertensive drug prescription. Among patients prescribed at least one antihypertensive drug class, guideline-recommended two-drug class combination therapy were prescribed in 54% of patients, with the highest proportion of 67% in patients with a prior myocardial infarction and the lowest proportion of 48% among patients with chronic kidney disease. These findings highlight a large missed opportunity for improving the guideline adherence of antihypertensive drug prescription in this population.

Poor hypertension awareness and underuse of guideline-recommended medications are critical factors contributing to poor hypertension control. Using data from 8095 hypertensive people aged ≥18 years from the National Health and Nutrition Examination Survey (2011–2018), we examined recent trends in racial and ethnic differences in awareness and antihypertensive medication use, and their association with racial and ethnic differences in hypertension control. Between 2011 and 2018, age-adjusted hypertension awareness declined for Black, Hispanic, and White individuals, but the 3 outcomes increased or did not change for Asian individuals. Compared with White individuals, Black individuals had a similar awareness (odds ratio, 1.20 [0.96–1.45]) and overall treatment rates (1.04 [0.84–1.25]), and received more intensive antihypertensive medication if treated (1.41 [1.27–1.56]), but had a lower control rate (0.72 [0.61–0.83]). Asian and Hispanic individuals had significantly lower awareness rates (0.69 [0.52–0.85] and 0.74 [0.59–0.89]), overall treatment rates (0.72 [0.57–0.88] and 0.69 [0.55–0.82]), received less intensive medication if treated (0.60 [0.50–0.72] and 0.86 [0.75–0.96]), and had lower control rates (0.66 [0.54–0.79] and 0.69 [0.57–0.81]). The racial and ethnic differences in awareness, treatment, and control persisted over the study period and were consistent across age, sex, and income strata. Lower awareness and treatment were significantly associated with lower control in Asian and Hispanic individuals ( P

ImportanceClinicians use blood pressure (BP) readings obtained during clinical encounters to detect hypertension and determine the adequacy of treatment. Variations in office-based BP measurements may obscure a hypertension diagnosis or overwhelm a signal of treatment response.ObjectivesTo quantify visit-to-visit variability (VVV) in BP values and its association with patient factors in real-world practice.Design, Setting and, ParticipantsRetrospective cohort analysis of adult patients (age ≥18 years) with at least two outpatient visits in the Yale-New Haven Health System between January 1, 2014 to October 31, 2018.Main Outcome and MeasuresPatient-level measures of VVV included standard deviation (SD) and coefficient of variation (CV) of a given patient’s BP across visits. We introduced a metric to determine the VVV between any two visits (dyad) to characterize the BP information that clinicians have as they formulate their recommendations. Dyad-level measures of VVV included difference, absolute difference, standardized difference, and absolute standardized difference between the two visits of a dyad.ResultsThe study population included 537,245 adults, with a total of 7,721,864 BP measurements. The mean age was 53.4 years (SD of 19.0), 60.4% were women, 69.4% were non-Hispanic White, and 18.1% with hypertension treatment. At the patient level, the mean intra-individual SD and CV were 10.6 mmHg and 0.08 mmHg. At the dyad level, the mean difference, absolute difference, standardized difference, and absolute standardized difference were -0.7 mmHg, 11.6 mmHg, 0 mmHg, and 0.09 mmHg, respectively. Given the observed VVV, if an antihypertensive medication truly reduced a patient’s SBP by 10 mmHg (the average BP-lowering effect reported in previous review), clinicians would expect to observe a reduction of SBP < 5mm Hg at the next visit 36.9% of the time. In the multivariable linear regression model, only 2% of the variance in absolute standardized difference was attributable to patient characteristics.Conclusions and RelevanceThe large VVV poses challenges for diagnosis, treatment, and monitoring of patients with hypertension based on BP readings in outpatient settings, supporting recent guidelines recommending home BP monitoring and ambulatory BP monitoring as out-of-office alternatives to establish diagnosis of hypertension and BP control.KEY POINTSQuestionWhat is the visit-to-visit variability (VVV) in blood pressure (BP) values and its association with patient factors in real-world practice?FindingsIn this retrospective cohort analysis that included 537,245 adults and 7,721,864 office-based BP measurements from a large health system, marked VVV was observed in BP values and the median absolute change between two consecutive visits was about 12 mmHg. The VVV was not significantly associated with patient demographic and clinical characteristics.MeaningThe large VVV poses challenges for diagnosis, treatment, and monitoring of patients with hypertension based on BP readings in outpatient settings, supporting recent guidelines recommending home BP monitoring and ambulatory BP monitoring as out-of-office alternatives to establish a new diagnosis of hypertension and BP control.

ObjectiveTo examine United States (US) trends in racial/ethnic differences in hypertension awareness and antihypertensive medication use, and whether these differences help explain racial/ethnic differences in hypertension control among adults from 2011 to 2018.DesignPopulation-based study.SettingNational Health and Nutrition Examination Survey (NHANES), 2011-2018.ParticipantsA nationally representative sample of US adults aged 18 years or older.Main outcome measuresHypertension awareness was defined as self-reported physician diagnosis of hypertension. Antihypertensive treatment was based on self-reported use of antihypertensive agents. Blood pressure (BP) control was measured systolic BP ResultsThis study included 8,095 adults with hypertension from NHANES 2011-2018. During the study period, age-adjusted hypertension awareness declined from 84.0% (95% confidence interval 79.5 to 86.2) to 77.5% (74.0 to 80.5), hypertension treatment declined from 77.3% (73.4 to 81.1) to 71.4% (69.0 to 73.8) and control rates declined from 51.9% (47.1 to 56.7) to 43.1% (39.7 to 46.5). These declines were consistent for Black, Hispanic, and White individuals, but the three outcomes increased or did not change for Asian individuals. Compared with White individuals, Black individuals did not have a significantly different awareness (odds ratio:1.20 [0.96 to 1.45]) and overall treatment rate (1.04 [0.84 to 1.25]), but received more antihypertensive medications if treated (1.41 [1.27 to 1.56]), and had a lower BP control rate (0.72 [0.61 to 0.83]); Asian and Hispanic individuals had significantly lower awareness rates (0.69 [0.52 to 0.85] and 0.74 [0.59 to 0.89], respectively), overall treatment rates (0.72 [0.57 to 0.88] and 0.69 [0.55 to 0.82]), received fewer medications if treated (0.60 [0.50 to 0.72] and 0.86 [0.75 to 0.96]), and had lower BP control rates (0.66 [0.54 to 0.79] and 0.69 [0.57 to 0.81]). The racial/ethnic differences in awareness, treatment, and BP control persisted over the study period and were consistent across age, sex, and income strata. Lower awareness and treatment were associated with lower BP control in Asian and Hispanic individuals, but not in Black individuals.ConclusionsHypertension awareness, treatment, and control declined from 2011-2018, and this decline was consistent for Black, Hispanic, and White individuals. BP control was worse for Asian, Black, and Hispanic individuals than for White individuals over the entire study period; this was explained partly by differences in awareness and treatment for Asian and Hispanic individuals, but not for Black individuals.What this Paper AddsSection 1: What is already known on this subject?Hypertension control rate has declined in the United States (US) since 2013, and this decline is more pronounced in Black and Hispanic communities.Section 2: What this study addsOur study shows that hypertension awareness, treatment, and control in the US have worsened from 2011 to 2018, and this trend was consistent for Black, Hispanic, and White individuals. Compared with White individuals, Black individuals had similar awareness and overall treatment rates, received more antihypertensive medications if treated, but had a lower control rate; Asian and Hispanic individuals had significantly lower awareness rates, overall treatment rates, received fewer medications if treated, and had lower control rates. Lower awareness and treatment were associated with lower BP control in Asian and Hispanic individuals, but not in Black individuals. These findings highlight the need for interventions to improve awareness and treatment among Asian and Hispanic individuals, and more investigation into the downstream factors that may contribute to the poor hypertension control among Black individuals.

The magnetic structures of MnBi

An increasing proportion of people in the US hospitalized for acute myocardial infarction (AMI) are younger than 55 years, with the largest increase in young women. Effective prevention requires an understanding of risk factors associated with risk of AMI in young women compared with men.To assess the sex-specific associations of demographic, clinical, and psychosocial risk factors with first AMI among adults younger than 55 years, overall, and by AMI subtype.This study used a case-control design with 2264 patients with AMI, aged 18 to 55 years, from the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study and 2264 population-based controls matched for age, sex, and race and ethnicity from the National Health and Nutrition Examination Survey from 2008 to 2012. Data were analyzed from April 2020 to November 2021.A wide range of demographic, clinical, and psychosocial risk factors.Odds ratios (ORs) and population attributable fractions (PAF) for first AMI associated with demographic, clinical, and psychosocial risk factors.Of the 4528 case patients and matched controls, 3122 (68.9%) were women, and the median (IQR) age was 48 (44-52) years. Seven risk factors (diabetes [OR, 3.59 (95% CI, 2.72-4.74) in women vs 1.76 (1.19-2.60) in men], depression [OR, 3.09 (95% CI, 2.37-4.04) in women vs 1.77 (1.15-2.73) in men], hypertension [OR, 2.87 (95% CI, 2.31-3.57) in women vs 2.19 (1.65-2.90) in men], current smoking [OR, 3.28 (95% CI, 2.65-4.07) in women vs 3.28 (2.65-4.07) in men], family history of premature myocardial infarction [OR, 1.48 (95% CI, 1.17-1.88) in women vs 2.42 (1.71-3.41) in men], low household income [OR, 1.79 (95% CI, 1.28-2.50) in women vs 1.35 (0.82-2.23) in men], hypercholesterolemia [OR, 1.02 (95% CI, 0.81-1.29) in women vs 2.16 (1.49-3.15) in men]) collectively accounted for the majority of the total risk of AMI in women (83.9%) and men (85.1%). There were significant sex differences in risk factor associations: hypertension, depression, diabetes, current smoking, and family history of diabetes had stronger associations with AMI in young women, whereas hypercholesterolemia had a stronger association in young men. Risk factor profiles varied by AMI subtype, and traditional cardiovascular risk factors had higher prevalence and stronger ORs for type 1 AMI compared with other AMI subtypes.In this case-control study, 7 risk factors, many potentially modifiable, accounted for 85% of the risk of first AMI in young women and men. Significant differences in risk factor profiles and risk factor associations existed by sex and by AMI subtype. These findings suggest the need for sex-specific strategies in risk factor modification and prevention of AMI in young adults. Further research is needed to improve risk assessment of AMI subtypes.

International audience; It is well known that the interaction between cascaded individually designed power conversion systems can cause instability. To overcome this issue, a Hamiltonian energy control scheme is proposed, which is based on passivity control theory and port-controlled Hamiltonian framework. A complementary PI adjustment term is also included in the control algorithm to eliminate the steady-state output voltage error caused by the parameter uncertainty. The proposed control approach is applied to three different cascade structures. First, the cascade structure between dc/dc converters is considered, and the detailed controller design is given. Second, the cascade connection of a single converter and its LC filter is studied. By placing the LC filter into the Hamiltonian model of the controlled converter system, the dynamic and potential instability caused by the filter can be adjusted. Finally, the cascade structure between subsystems including filters and converters, which are common in microgrids, is studied. By using the Hamiltonian function (storage function) as the Lyapunov function candidate, the large-signal stability of each controlled converter system is proved. When the cascade structure contains multiple controlled converter systems, the stability of the entire cascaded system is guaranteed by the superposition of multiple Lyapunov functions. A 3.5 kW 220-270-350 V test bench is built in the laboratory to demonstrate the application of the proposed control approach to these three cascade structures.

In this paper, a hybrid power system for electric vehicle with fuel cell stack and Lithium-ion battery is designed and power converters transferring power are modeled. Besides, an improved state machine strategy is developed to split the power produced by power sources. The rules are designed to avoid battery overcharging in high SOC and over discharging in low SOC, and avoid charge and discharge frequently in normal SOC area while decreasing the hydrogen consumption. The simulation results verify that the improved state machine strategy performs better than traditional state machine strategy.

As a renewable and efficient power source, proton exchange membrane fuel cells (PEMFCs) are receiving more and more attention from the world, but it still has shortcomings with poor durability and insufficient reliability, so the purpose of this paper is to effectively improve the reliability and durability of PEMFCs by a data-driven fault diagnosis method. In this method, principal component analysis (PCA) is first adopted to reduce the dimensionality of fault data. Then, a classification method named eXtreme Gradient Boosting (XGBoost) which based on boosting algorithm is used to classify these data. In the end, the experiment is proposed to verify the diagnostic performance of this method. The result shows that the method can effectively identify four healthy states of membrane drying failure, hydrogen leakage failure, normal state as well as unknown state, the diagnostic accuracy can reach 99.72%, and the diagnosis period is 0.17751 s, which is suitable for online implementation.

Experiments reveal that unusual surface behavior at the terminations of a recently discovered magnetic topological insulator depends on the interplay between different building blocks within the material.

The magnetic structures of MnBi2Te4(Bi2Te3)n can be manipulated by tuning the interlayer coupling via the number of Bi2Te3 spacer layers n, while the intralayer ferromagnetic (FM) exchange coupling is considered too robust to control. By applying hydrostatic pressure up to 3.5 GPa, we discover opposite responses of magnetic properties for n = 1 and 2. MnBi4Te7 stays at A-type antiferromagnetic (AFM) phase with a decreasing N\'eel temperature and an increasing saturation field. In sharp contrast, MnBi6Te10 experiences a phase transition from A-type AFM to a quasi-two-dimensional FM state with a suppressed saturation field under pressure. First-principles calculations reveal the essential role of intralayer exchange coupling from lattice compression in determining these magnetic properties. Such magnetic phase transition is also observed in 20% Sb-doped MnBi6Te10 due to the in-plane lattice compression., Comment: 20 pages, 5 figures

Traditional transmission line design often relies on human experience and is highly subjective. In order to realize intelligent transmission line route optimization, this paper relies on the established geographic information system platform, selects 119°14’50” east longitude to 119°17’56” east longitude, and 31°57’34” north latitude to 31°54’49 north latitude. For the rectangular area of”, first rasterize the area into a 20*20 grid according to the rasterization model, then enter the coordinates of the avoidance area, and optimize the shortest transmission line path according to the ant colony algorithm. Then based on the rasterized matter-element scheme, an improved matter-element extension evaluation method is used to comprehensively evaluate the feasible points around the matter-element node of each path, and the point with the best economic efficiency is selected as the transit point of the transmission line. Optimization of the entire transmission line. The results of the numerical example analysis prove that the method has a better auxiliary decision-making effect on the erection of transmission lines.

This paper presents a systematic derivation of a small signal model of current-fed half bridge isolated dc/dc converter for the hybrid electric vehicle based on the lithium battery and fuel cell. The reflected output voltage across the power semiconductor devices can naturally be clamped at V°/n by a secondary-modulation strategy without any additional circuit, which can reduce footprints and cost. Moreover, the soft switch of all can be achieved resulting in low switching losses and higher efficiency due to ZCS/ZVS. In order to maintain the constant bus voltage and the balanced two-way inductor current, a small signal model using state-space averaging technique is deduced and the dual closed loop controller is designed in detail. The co-simulation of PSIM and MATLAB/SIMULINK is used to verify the effectiveness of the controller when the load step-changes in case of the different input voltage.

In the design process of the transmission line of the traditional substation system, the plans and decisions often made by people, resulting in unsatisfactory line design results, which are not the most economical optimal results, and they are not even considered in the preliminary planning. Going to areas where lines cannot be erected has caused slow progress and poor accuracy in the feasibility study stage. This paper combines the ant colony intelligent algorithm with the geographic information system, and proposes a substation transmission line optimization model, which outputs the optimal path by inputting geographic information data. This model analyzes the entire process of the transmission line design stage and realizes the intelligent line selection. The analysis of the example in the article proves that the model has a better auxiliary function for the work of the substation line planning stage.