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Modular multilevel converters (MMCs) are characterized by the multi-harmonic coupling interactions among internal dynamics. In this work, multiple d-q references and multi-harmonic frames, which are developed through dynamic phasor and harmonic state-space, are used to derive the generalized impedance models of MMC in the d-q and modified sequence domain, respectively. Although some previous researches have been devoted to revealing the equivalence of different impedance models, this paper attempts to elaborate the relation of different multi-frequency modeling approaches, and to provide a more comprehensive review of MMC impedance models. A rigorous comparison of modeling procedure, impedance response and stability analysis result between different MMC models is conducted. It is demonstrated that the MMC impedance models in the two domains can be related by a generic linear transformation matrix. Furthermore, the stability analysis results given by generalized Nyquist criterion are identical in these two domains. Application recommendations for different impedance models are given as well. The developed impedance models and their effectiveness for stability and resonance analysis are validated by a 501-level aggregated model in MATLAB/SIMULINK.

Diabetic retinopathy (DR) is a leading cause of irreversible vision loss in working-age populations. FTO is an N6-methyladenosine (m6A) demethylase that participates in various biological events, while its role in DR remains elusive. Herein, we detected elevated FTO expression in retinal proliferative membranes of DR patients. FTO promoted endothelial cell (EC) cell cycle progression and tip cell formation to facilitate angiogenesisin vitro, in mice and in zebrafish. FTO also regulated EC-pericyte crosstalk to trigger diabetic microvascular leakage, and mediated EC-microglia interactions to induce retinal inflammation and neurodegenerationin vivoandin vitro. Mechanistically, FTO affected EC features via modulatingCDK2mRNA stability in an m6A-YTHDF2-dependent manner. FTO up-regulation under diabetic conditions was driven by lactate mediated histone lactylation. FB23-2, an inhibitor to FTO’s m6A demethylase activity, suppressed angiogenic phenotypesin vivoandin vitro. Noteworthy, we developed a nanoplatform encapsulating FB23-2 for systemic administration, and confirmed its targeting and therapeutic efficiencies in mice. Collectively, our study demonstrated that FTO coordinates EC biology and retinal homeostasis in DR, providing a promising nanotherapeutic approach for DR.

AIM: To evaluate the differences of macular vascular network measured by optical coherence tomography angiography(OCTA)between severe non-proliferative diabetic retinopathy(S-NPDR)eyes and health eyes, and explore the changes of these OCTA characteristics in patients with S-NPDR before and after panretinal photocoagulation(PRP).METHODS: This was a prospective study including 31 eyes from 18 consecutive patients with S-NPDR and 31 eyes of healthy subjects. We measured macular vascular density and foveal avascular zone(FAZ)area and volume by an OCTA device.RESULTS: Compared to the normal control group, in superficial retinal capillary plexus(SCP), macular vascular density decreased in S-NPDR group, except foveal vascular density unchanged. Consistently, in deep retinal capillary plexus(DCP), macular vascular density was also lower in S-NPDR group. In addition, FAZ area and volume expanded in S-NPDR eyes. At 6mo post-PRP in S-NPDR eyes, foveal SCP and DCP densities increased significantly, while FAZ area and volume decreased. At 3mo post-PRP, only foveal vascular density in DCP increased. The changes of foveal SCP and DCP densities as well as FAZ area and volume were not statically significant at 1mo post-PRP.CONCLUSION: Macular vascular network was impaired in S-NPDR assessed by OCTA. Although OCTA parameters were not significantly affected by PRP in 1 and 3mo period, at 6mo follow-up parameters became significant after PRP.

To explore the efficacy and safety of Zhuang medicine medicated thread moxibustion (ZMTM) on psoriasis vulgaris.A multicenter, randomized, parallel controlled clinical trial was designed. A total of 241 outpatients with psoriasis vulgaris were randomly divided into a control group (120 cases) and a treatment group (121 cases) using a central block randomization from June 2015 to May 2018. The control group was treated with Western medicines alone including pidotimod dispersible tablets, vitamin B compound tablets, and compound cod liver oil-zinc oxide ointment. The treatment group was treated with ZMTM every 2 days combined with Western medicines. The two groups received continuous intervention for 30 days. The primary outcome was Psoriasis Area and Severity Index (PASI), and the secondary outcomes included Itch Rating Scale, Dermatology Quality of Life Index (DLQI), Hamilton Anxiety Rating Scale (HAMA), as well as PASI response rate. Meanwhile, adverse events were evaluated during the whole clinical trial. Follow-up was carried out 30 days after treatment.There were 5 cases of shedding in this trial. In intention-to-treat analysis, 236 cases were included and each group contained 118 cases. On the 30th and 60th days, PASI scores of patients in each group were significantly lower than that at baseline (P0.01) and the PASI score reduction of the treatment group was greater than that of the control group (P0.01). Itch Rating Scale, DLQI, and HAMA scale were decreased in both groups after treatment, and the treatment group showed a better therapeutic effect (P0.01). The response rates of PASI 50 and 75 were significantly higher than those in the control group [81.4% (96/118), 43.2% (51/118) vs. 41.5% (49/118), 11.0% (13/118), respectively, P0.05]. During follow-up, the improvements in scores of PASI, Itch Rating Scale, DLQI, and HAMA of the treatment group were significantly greater than those of the control group (P0.01). The response rates of PASI 50 and 75 in the treatment group were significantly higher than those in the control group, respectively (both P0.05). No obvious adverse reaction was found in either group.ZMTM combined with Western medicines showed a better therapeutic effect in the treatment of psoriasis vulgaris without obvious adverse reaction. (Trial Registration No. ChiCTR-IOR-16008159).

Microvascular dysfunction (MVD) has long plagued the medical field despite improvements in its prevention, diagnosis, and intervention. Microvascular lesions from MVD increase with age and further lead to impaired microcirculation, target organ dysfunction, and a mass of microvascular complications, thus contributing to a heavy medical burden and rising disability rates. An up-to-date understanding of molecular mechanisms underlying MVD will facilitate discoveries of more effective therapeutic strategies. Recent advances in epigenetics have revealed that RNA methylation, an epigenetic modification, has a pivotal role in vascular events. The N

Discoxenus shenzhenensis Xu, Cai, Zeng & Song sp. nov. (Chinese name: 深圳DZDKOiffl) Figs. 1, 3–16 Type material. Holotype. China: male on slide, glued on a card with labels as follows: “ China: Guangdong, Shenzhen, Wutong Mt., 22°34′48″N, 114°12′36″E; alt. 500 m, 21.IX.2021, Yujie Cai & Chenglin Zhou leg.” “ Holotype / Discoxenus shenzhenensis / Xu, Cai, Zeng & Song” [red handwritten label] (SHNU). Paratypes. 1 male, same data as holotype (SHNU). 1 male, Guangdong Prov., Guangzhou, Tianhe Dist., Guangdong Forestry Vocational and Technical School, Longdong; 23°11′29″N, 113°22′39″E; alt. 30–100 m, 1.VII.2012, Huang S-B leg. (SHNU). 1?, China: Guangdong, Zhongshan City, Wuguishan (I桂山), 22°25′56.79″N, 113°26′40.46″E, 21.X.–18.XI.2020, by FIT (SHNU). Diagnosis. The genus is currently subdivided into two species groups: the Discoxenus assmuthi group and the D. latiabdominalis group (Kanao & Maruyama 2015). According to the tergite X with posterior half covered with a batch of setae, the small basal capsule and strongly developed distal crest of aedeagal median lobe, Discoxenus shenzhenensis sp. nov. belongs to the D. assmuthi species group, it can be easily distinguished from all congeners by a combination of the following two character states: macrochaetotaxy of tergites III–VIII (6, 6, 6, 6, 6, 6); elytra and abodmen sparesly covered with relatively long yellow setae. The new species is closely allied to D. katayamai Kanao & Maruyama, 2010 from Thailand and Cambodia in general habitus, but can be readily separated from it by antennal segment XI approximately 2.1 times longer than wide (in D. katayamai, antennal segment XI thick, length approximately 1.4 times as long as wide); the longer incisor tooth of both mandibles; the molar tooth of right mandible very small; the slenderer apical lobe of aedeagal median lobe and the longer apical lobe of paramere. The key to the Southeast Asian species of Discoxenus (Kanao & Maruyama 2015) should be modified at the couplet #2 as follows to accommodate the new species: 2. Elytra sparsely covered with relatively long setae.......................................................... 2a - Elytra covered with no or few short setae except for anterolateral outer corner..................................... 3 2a. Antennal segment XI approximately 1.4 times longer than wide; the molar tooth of right mandible distinct.... D. katayamai - Antennal segment IX approximately 2.1 times longer than wide; the molar tooth of right mandible very small............................................................................................. D. shenzhenensis sp. n. Description. Body (Figs 1, 18) smooth, glabrous. Coloration: Light reddish-yellow overall. Head (Fig. 4) approximately 1.5 times wider than long. Antenna (Fig. 3) with segment II with 3 macrosetae; segment XI approximately 2.1 times longer than wide, widest around middle. Labrum (Fig. 5) with anterior margin slightly concave at middle; median projection of apodeme short, with apex rounded; 5–6 lateral setae present in ventral view. Mandibles (Figs. 7–8), covered with 38–42 pores. Left mandible (Fig. 7) with adoral margin moderately pointed around middle. Right mandible (Fig. 8) with molar tooth almost reduced. Maxillary palpal segment III approximately 2.1 times longer than wide. Mentum (Fig. 6) approximately 2.4 times wider than long, covered with around 58 pores. Labium with prementum covered with approximately 8 pores. Pronotum (Fig. 12) covered with approximately 68 macrosetae. Elytron (Fig. 13) transverse, sparsely covered with yellow setae, 16 macrosetae present on disc. Metaventrite approximately 1.8 times longer than mesoventrite. Tergites (Fig. 1) and sternites sparsely covered with yellow setae. Macrochaetotaxy of abdominal tergites III– VIII = 6, 6, 6, 6, 6, 6. Sternite III with posterior half densely covered with setae. Sternites IV–VII with posterior half sparsely covered with setae. Sternites III–VII with 4–8 macrosetae at posterior margin. Male. Tergite VIII (Fig. 9) with posterior margin rounded, 3 pairs of macrosetae present at posterior margin, with 2 pairs of macrosetae around middle. Sternite VIII (Fig. 10) with posterior margin slightly rounded, 3 pairs of macrosetae present at posterior margin, with 2 pairs of macrosetae at middle. Median lobe of aedeagus narrowed apically in ventral view (Fig. 14); basal capsule with distal crest large in lateral view (Fig. 15); apical lobe less than half as wide as basal capsule in lateral view (Fig. 15). Paramere (Fig. 16) with paramerite approximately 3 times wider than condylite; velar sac sclerite with 6–9 setae; apical lobe with 3 minute setae at apex. Female. Unknown. Measurements. BL: 1.67–1.92 mm; FBL: 0.86–0.89 mm; PL: 0.61–0.65 mm; PW: 0.91–0.97 mm; EL: 0.24– 0.25 mm; EW: 0.94–1.01 mm; PL/PW: 0.67; EL/EW: 0.24–0.27. Distribution. China (Guangdong). Symbiotic host. Odontotermes sp. (Fig. 2) Etymology. The species is named after its type locality, Shenzhen., Published as part of Xu, Wang, Cai, Yu-Jie, Zeng, Qing-Huai, Wang, Wei-Min, Yu, Xin-Fan & Song, Xiao-Bin, 2022, Discoxenus Wasmann new to China with description of a new species (Coleoptera: Staphylinidae: Aleocharinae), pp. 389-393 in Zootaxa 5175 (3) on pages 390-391, DOI: 10.11646/zootaxa.5175.3.6, http://zenodo.org/record/7003704, {"references":["Kanao, T. & Maruyama, M. (2015) Eight new species, a new record, and redescription of the genus Discoxenus Wasmann, 1904: The first record of termitophilous rove beetles in Cambodia (Coleoptera: Staphylinidae: Aleocharinae). Zootaxa, 4044 (2), 201 - 223. https: // doi. org / 10.11646 / zootaxa. 4044.2.2","Kanao, T., Maruyama, M. & Sakchoowong, W. (2010) Two new species of Aleocharinae (Coleoptera, Staphylinidae) found in the fungus gardens of Odontotermes termites (Isoptera, Termitidae, Macrotermitinae) in Khao Yai National Park, Thailand. Zookeys, 49, 77 - 86. https: // doi. org / 10.3897 / zookeys. 49.468"]}

Xu, Wang, Cai, Yu-Jie, Zeng, Qing-Huai, Wang, Wei-Min, Yu, Xin-Fan, Song, Xiao-Bin (2022): Discoxenus Wasmann new to China with description of a new species (Coleoptera: Staphylinidae: Aleocharinae). Zootaxa 5175 (3): 389-393, DOI: https://doi.org/10.11646/zootaxa.5175.3.6

A $\\boldsymbol d$ - $\\boldsymbol q$ frame impedance model of modular multilevel converter (MMC), which is suitable for high-frequency resonance (HFR) analysis under the condition that the number of submodules in MMC reaches hundreds level, is presented in this work. A 10th-order dynamic phasor model for the MMC is linearized and combined with a control subsystem model. A modular modeling approach based on transfer matrix is applied to the overall linearized model to derive the impedance model. The validity and accuracy of the model are verified using a 501-level MMC aggregated model in SIMULINK. Results show that the impedance model has satisfactory accuracy in the frequency ranging from 1 to 3000 Hz. Then, the impedance model is used to analyze an HFR accident in a realistic MMC project. Therefore, a high time delay in controller is proved can provide negative resistance in high frequency and cause instability.

As novel anodic materials for lithium-ion batteries (LIBs), transitional metal selenites can transform into metal oxide/selenide heterostructures in the first cycle, which helps to enhance the Li

In order to overcome the weakness of dc line protection under high impedance fault, a traveling wave similarity based pilot protection method is proposed using improved Hausdorff Distance algorithm. The issue of asynchronous data, noise and anomalies are solved with the improved Hausdorff Distance algorithm. The instantaneous frequency based wave head detection method is used to overcome the problem of delay in protection start-up. Based on this protection scheme, external fault can be distinguished from internal faults regardless of fault impedance, fault location and fault type. Moreover, the faulty pole and fault direction are recognized via ratio of transient energy at line terminals. Taking the Zhangbei high voltage dc transmission project as an example, a four-terminal ring type dc grid model is developed in PSCAD/EMTDC platform for fault simulation and the data processing is performed in MATLAB platform. Based on the theoretical analysis and simulation study, the proposed pilot protection is verified with excellent fault impedance withstanding ability and robustness against noise, abnormal data and asynchronous data.

For the high-frequency resonant accident of modular multilevel converter (MMC) in real engineering, in this paper, the 10th order state-space model of MMC is established based on the dynamic phasor method. The state-space model of MMC controller for power control is established according to the practical engineering. Then the time delay of input and output is considered in the controller, and the Pade fitting in state-space model applicable to the eigenvalue method is introduced to the complete state space model of MMC. Based on the proposed model, the MMC high-frequency resonance phenomenon is analyzed by the eigenvalue method, and the accuracy of the model is verified by simulation results. Besides, it is demonstrated that high time delay causes high-frequency resonance in the MMC system based on the participation factor and the system eigenvalue trajectory. Then, the coupling relationship between the input and output time delay inside the controller and the d-q axis time delay is investigated, and a new time delay compensation method to suppress high-frequency resonance is proposed based on Pade fitting, which can be used jointly with the traditional method with good effect.

This study presents a travelling wave (TW)-based method for locating DC line faults in a modular multilevel converter (MMC)-based high-voltage direct current (HVDC) system by using local information. Pole voltage signals are adopted and denoised via stationary wavelet transform (SWT) with improved threshold functions. Hankel matrix-based singular value decomposition (SVD) is utilised to detect TW arrivals. The arrival times of incidental and reflected wave heads are observed in SVD result. The reflected wave heads from the fault point and the opposite end can be discriminated by comparing surge polarities in SVD result. The proposed method relies on the TW principle but is independent of TW propagation velocity. The feasibility of the proposed algorithm is evaluated considering potential factors, such as fault resistance, close-in fault, remote fault, sampling rate and noise. The superiority of this method is validated by comparing it with other signal-processing techniques and TW-based fault location principles. Electromagnetic transient simulation of the multi-terminal HVDC system on Power Systems Computer Aided Design / Electromagnetic Transients including DC (PSCAD/EMTDC) is conducted to provide fault TW signals, which are analysed in MATLAB. A corresponding equivalent test model developed in a real-time digital simulator is also provided for conducting a supplementary study to verify and further research this fault location method.