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The design optimization of a direct-drive permanent magnet synchronous generator (DDPMSG) is of great significance for wind turbines because of its unique advantages. This paper proposes a two-stage model to realize multi-objective design optimization for a 6 MW DDPMSG. In the first stage, a surrogate optimized response surface model based on an improved sparrow search algorithm (ISSA) was established for modeling the cogging torque and generator efficiency. In the second-stage model, a multi-objective optimization model is proposed to optimize the cogging torque and generator efficiency of the DDPMSG. Finally, the proposed two-stage model was used for a 6 MW DDPMSG design optimization, and the simulation results demonstrated the superiority and rationality of the proposed model. In the first-stage model, the proposed surrogate model based on the ISSA had a better modeling accuracy and lower errors. Compared with traditional response surface models and correlation analysis models, the proposed optimized surrogate model reduced errors in the cogging torque by 34.63% and 42.97%, respectively, while the errors in the efficiency models were reduced by 12.92% and 60.78%, respectively, which indicates the superiority of the first-stage model. In the second stage, compared with the single-objective optimization model, the multi-objective optimization model achieved a trade-off optimization between the cogging torque and the efficiency. Compared with the cogging torque optimization model, the proposed model optimized the efficiency by 101.41%. Compared with the efficiency optimization model, the proposed model reduced the cogging torque by 16.67%. These results verified the superiority and rationality of the second-stage model. [ABSTRACT FROM AUTHOR]

Wind power is one of the cheapest and direct methods to alleviate negative impacts on environment therefore the demand of efficient wind energy conversion system is increasing. Uneven distribution of wind impacts the performance of Wind Turbine (WT) system so constant and noise free power at output is required. The pitching angle varies according to the Wind Speed (WS), and the power output equation of the entire WT system depends upon WT pitch angle. Pitch control is widely used to optimize power above rated WS. This paper proposes an efficient adaptive pitch control controller to maintain the output power of a 5 MW WT in dynamic wind conditions. Compared to low level control loops (such as PI), this illustrates the effectiveness of the proposed controller. The model was tested in a 5 MW WT GH bladed system.

Societal Impact Statement: Crop wild relatives represent precious genetic resources for crop improvement. Investigating their local adaptation to marginal environments is important for the utilization of wild genetic resources. Oryza officinalis and Oryza granulata are wild relatives of cultivated rice and possess genes that convey resistance to insects, disease, and tolerance to shade and drought. The northern edge for the distribution of these two lies in China where populations are facing habitat destruction. This study found that the northern marginal populations of both species have adapted to local conditions, with specific implications for the conservation and utilization of wild rice. Summary: O. officinalis and O. granulata, wild relatives of cultivated rice, represent important gene reservoirs with the potential to improve rice with respect to insect resistance and stress tolerance. However, the northern marginal populations of these two species in China are facing habitat destruction.Here, we investigated the genetic diversity and divergence of northern marginal populations of O. officinalis and O. granulata. The genomic variation of two species was examined by whole‐genome sequencing on 357 individuals. Generalized dissimilarity modeling was applied to investigate the effects of geographic and environmental isolation on population differentiation. Genetic‐environment association analysis and genome‐wide FST outlier scans were used to identify environmentally driven signals of selection.The marginal populations of both species exhibited low genetic diversity and obvious genetic differentiation stemmed from the joint effects of isolation by geographic distance and the environment. Both genomes exhibited specific signals of adaptation to cold environments in the north.Investigation of the divergence and adaptation of marginal populations of O. officinalis and O. granulata will help us to determine how wild rice can adapt to local environments, thus allowing for the development of scientific conservation policies and the identification of new genetic resources for rice with improved resistance. [ABSTRACT FROM AUTHOR]

Objective: Primary angiitis of the central nervous system (PACNS) is a rare vasculitis restricted to the brain, spinal cord, and leptomeninges. This study aimed to describe the imaging characteristics of patients with small vessel PACNS (SV‐PACNS) using 7 T magnetic resonance imaging (MRI). Methods: This ongoing prospective observational cohort study included patients who met the Calabrese and Mallek criteria and underwent 7 T MRI scan. The MRI protocol includes T1‐weighted magnetization‐prepared rapid gradient echo imaging, T2 star weighted imaging, and susceptibility‐weighted imaging. Two experienced readers independently reviewed the neuroimages. Clinical data were extracted from the electronic patient records. The findings were then applied to a cohort of patients with large vessel central nervous system (CNS) vasculitis. Results: We included 21 patients with SV‐PACNS from December 2021 to November 2023. Of these, 12 (57.14%) had cerebral cortical microhemorrhages with atrophy. The pattern with microhemorrhages was described in detail based on the gradient echo sequence, leading to the identification of what we have termed the "coral‐like sign." The onset age of patients with coral‐like sign (33.83 ± 9.93 years) appeared younger than that of patients without coral‐like sign (42.11 ± 14.18 years) (P = 0.131). Furthermore, the cerebral lesions in patients with cortical microhemorrhagic SV‐PACNS showed greater propensity toward bilateral lesions (P = 0.03). The coral‐like sign was not observed in patients with large vessel CNS vasculitis. Interpretation: The key characteristics of the coral‐like sign represent cerebral cortical diffuse microhemorrhages with atrophy, which may be an important MRI pattern of SV‐PACNS. ANN NEUROL 2024;96:194–203 [ABSTRACT FROM AUTHOR]

Objective: Plasma exchange (PE) and immunoadsorption (IA) are recognized as effective ways to treat attacks in AQP4 antibody‐positive NMOSD, but high‐quality evidence was lacking. To evaluate the efficacy and safety of PE/IA plus intravenous methylprednisolone (IVMP) in NMOSD attacks using propensity scores to match IVMP as control. Methods: Patients were from a prospective observational cohort study. Stratification and interval propensity score matching (PSM) were used to reduce selection bias by matching baseline characteristics (gender, age, time to IVMP, EDSS at attack) between PE/IA + IVMP and IVMP group (in a ratio of 1:2). The primary endpoint of efficacy was EDSS change at 6 months. Adverse events and changes in laboratory tests were recorded. Results: Four hundred and eleven attacks of 336 patients were screened for PSM, and 90 attacks (30 PE/IA + IVMP and 60 IVMP) were included in the analysis. There were significant differences in EDSS [6.25 vs. 6.75; IQR (4.50–8.38 vs. 5.00–8.00), p = 0.671] and visual acuity [median logMAR = 0.35 vs. 1.00; IQR (0.30–0.84 vs. 0.95–1.96), p = 0.002] change between two groups at 6 months. PE/IA + IVMP treatment demonstrated predictive capacity for good recovery as indicated by an area under the curve (AUC) of 0.726. Fibrinogen reduction was found during PE/IA + IVMP treatment [n = 15 (50.00%)], but no severe adverse events led to apheresis treatment discontinuation. Discussion: After PSM analysis, IVMP+PE/IA in acute attack of NMOSD achieved better and continuous improvement in neurological function within 6 months compared with IVMP alone. PE/IA treatment showed a good safety profile. [ABSTRACT FROM AUTHOR]

The purpose of the experiment was to study the degradation characteristics of the products of four roughage feeds, sugarcane tail leaves, corn stalks, elephant grass and cassava branch, fermented by cellulase (CE) in buffalo rumen, so as to provide a reference for the selection and utilization of roughage in buffalo breeding. Three buffaloes with permanent rumen fistula were used as experimental animals. Nylon bag method was used to determine the nutritional components and rumen degradation characteristics of four kinds of roughage and their products after CE fermentation. The results showed that before fermentation, the content of crude protein (CP) in sugarcane tail leaves and elephant grass was significantly higher than that in corn stalks and cassava branch (P<0.05). The content of neutral detergent fiber (NDF) in cassava branch was the lowest (P<0.05), and the content of acid detergent fiber (ADF) was the highest (P<0.05). After CE treatment, the content of CP in fermentation group increased in different degrees, while the content of NDF and ADF decreased in different degrees. Before fermentation, the effective degradation rates of all nutrients were as follows: Elephant grass > sugarcane tail leaf > corn stalk > cassava branch. The effective degradation rates of DM, NDF, and ADF of elephant grass were significantly higher than those of other groups (P<0.05), the effective degradation rates of CP of elephant grass were significantly higher than those of corn stalk and cassava branch (P<0.05), and the effective degradation rates of nutrients of cassava branch were significantly lower than those of other groups (P<0.05). After CE treatment, compared with the control group, the effective degradation rates of DM, CP, NDF, and ADF in the fermentation group were improved to varying degrees. The study indicates that the feed value of the four kinds of roughage is as follows: Elephant grass > sugarcane tail leaf > corn straw > cassava branch. Adding CE can improve the rumen degradation rate of the four kinds of roughage. [ABSTRACT FROM AUTHOR]

Energy demand is rapidly increasing with the industrialization and economic growth. Industrialization leads to enhancing global warming along with acid rain, environmental pollution. Therefore, the need for power systems, which composed of alternate energy sources. Mainly, the researchers are contributing to the field of wind and solar power. Wind energy is getting prime importance because of its abundant nature and totally emission free. In addition to it, many researchers are focusing on solar power to enhance its output efficiency, which is very beneficial to fulfill the energy demand. Multi energy systems (MES), which include wind, solar, battery system, and utility grid are used. This paper emphasizes the integration of various energy sources. The research proposes the design of various energy systems such as wind, solar and battery storage along with the utility grid. The sources are coupled and connected to the alternating current (AC) load. The proposed system is designed and simulated by using MATLAB/Simulink. The output power results of the various interconnected sources are satisfactory with the high power quality.

Multiple sclerosis (MS) was defined as a rare disease in China due to its low prevalence. For a long time, interferon β was the only approved disease-modifying therapy (DMT). Since the first oral DMT was approved in 2018, DMT approval accelerated, and seven DMTs were approved within 5 years. With an increasing number of DMTs being prescribed in clinical practice, it is necessary to discuss the standardized MS treatment algorithms depending on the disease activity and DMT availability. In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country. Plain language summary: Treatment algorithms of relapsing multiple sclerosis in China In this review paper, more than 20 Chinese experts in MS have reviewed the therapeutic progress of MS in China and worldwide and discussed algorithms for treating relapsing MS (RMS) based on the available DMTs in China, providing insights for establishing the standardized RMS treatment algorithms in this country: 1) CIS and RRMS account for more than 90% of the MS patients and most of them are mild to moderate; 2) MS patients should initiate DMT treatments as soon as the disease has been diagnosed in order to reduce the risk of disease progression; 3) Patients who have been diagnosed with MS should start treatment with fundamental DMTs unless the disease course has been highly active; 4) MAGNIMS score may be a suitable and simplified assessment tool for measuring treatment response to DMTs; 5) Patients treated with corticosteroids and NSIS should be switched to the standardized DMT treatment during remission in accordance with disease activity. [ABSTRACT FROM AUTHOR]

Wind turbine blades, being flexible, are susceptible to damage during typhoons. Studying the aeroelastic response of these blades in typhoon conditions is crucial for providing a theoretical foundation for their optimization and design. This research focuses on the NREL 5 MW flexible blade, employing the B-L stall model for dynamic inflow and geometrically exact beam theory to develop an aeroelastic model capable of predicting the blade's flutter limit. Through quantitative analysis, we assess the stability of the wind turbine's flexible blade under typhoon conditions and examine the blade tip's transient response. The findings indicate that the model's flutter speed is 21.5 rpm, marked by a significant increase in tip deflection's mean square error of over 80% and a coupling of flapwise and torsional modes at 4.81 Hz. The blade tip's transient response under typhoon conditions does not satisfy the flutter criterion, thus preventing instability. Under typhoon conditions, the deflection in the flapwise, edgewise, and twist directions of the blade shows an increase of 12.1%, 10.5%, and 119.2%, respectively, compared to standard operating conditions. [ABSTRACT FROM AUTHOR]

The ability of the floating offshore wind turbine foundation to withstand harsh wind and wave conditions is intrinsically linked to the meticulousness employed in the design of the mooring system. Therefore, it is vital to conduct research to reveal the variations in sensitivity of new mooring materials parameters and the response characteristics of the foundation in the presence of intricate operational circumstances. A fully coupled time-domain dynamic analysis is performed via the commercial software AQWA to examine the VolturnUS-S semi-submersible foundation, specifically engineered to support the IEA 15 MW offshore reference wind turbine. The numerical simulation results indicate that synthetic fibers, specifically Aramid and high-modulus polyethylene, can replace the steel wire as mooring materials. At the same time, the mooring arrangement, length, diameter, and fairlead position influence foundation motions and mooring tensions, bringing valuable insight into the fluctuation patterns of these responses. [ABSTRACT FROM AUTHOR]

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy of the central nervous system, mediated by antibodies against aquaporin-4 water channel protein (AQP4-Abs), resulting in damage of astrocytes with subsequent demyelination and axonal damage. Extracellular communication through astrocyte-derived extracellular vesicles (ADEVs) has received growing interest in association with astrocytopathies. However, to what extent ADEVs contribute to NMOSD pathogenesis remains unclear. Here, through proteomic screening of patient-derived ADEVs, we observed an increase in apolipoprotein E (APOE)–rich ADEVs in patients with AQP4-Abs–positive NMOSD. Intracerebral injection of the APOE-mimetic peptide APOE130–149 attenuated microglial reactivity, neuroinflammation, and brain lesions in a mouse model of NMOSD. The protective effect of APOE in NMOSD pathogenesis was further established by the exacerbated lesion volume in APOE-deficient mice, which could be rescued by exogenous APOE administration. Genetic knockdown of the APOE receptor lipoprotein receptor–related protein 1 (LRP1) could block the restorative effects of APOE130–149 administration. The transfusion ADEVs derived from patients with NMOSD and healthy controls also alleviated astrocyte loss, reactive microgliosis, and demyelination in NMOSD mice. The slightly larger beneficial effect of patient-derived ADEVs as compared to ADEVs from healthy controls was further augmented in APOE−/− mice. These results indicate that APOE from astrocyte-derived extracellular vesicles could mediate disease-modifying astrocyte-microglia cross-talk in NMOSD. Editor's summary: Neuromyelitis optica spectrum disorder (NMOSD) is a demyelinating central nervous system disorder initiated by an astrocyte-targeted autoimmune response. Here, Jiang et al. investigated how signaling by astrocytic extracellular vesicles (ADEVs) affects NMOSD pathogenesis. The researchers found increased expression of apolipoprotein E in patient-derived ADEVs and showed that administration of ADEVs or an APOE-mimicking peptide decreased neuroinflammation and brain lesions in a mouse model of NMOSD. The protective effects of APOE were blocked by genetic deletion of low-density lipoprotein receptor–related protein 1 (LRP1). These results suggest that signaling by ADEVs might keep neuroinflammation and progression of NMOSD in check. —Daniela Neuhofer [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical potential and safety of Moluodan to reverse gastric precancerous lesions. Methods: Patients aged 18–70 years diagnosed with moderate‐to‐severe atrophy and/or moderate‐to‐severe intestinal metaplasia, with or without low‐grade dysplasia, and negative for Helicobacter pylori were recruited in this randomized, double‐blind, parallel‐controlled trial. The primary outcome was the improvement of global histological diagnosis at 1‐year follow‐up endoscopy using the operative link for gastritis assessment, the operative link for gastric intestinal metaplasia assessment, and the disappearance rate of dysplasia. Results: Between November 3, 2017 and January 27, 2021, 166 subjects were randomly assigned to the Moluodan group, 168 to the folic acid group, 84 to the combination group, and 84 to the high‐dose Moluodan group. The improvement in global histological diagnosis was achieved in 60 (39.5%) subjects receiving Moluodan, 59 (37.8%) receiving folic acid, 26 (32.1%) receiving the combined drugs, and 36 (47.4%) receiving high‐dose Moluodan. Moluodan was non‐inferior to folic acid (95% confidence interval: −9.2 to 12.5; P = 0.02). High‐dose Moluodan had a trend for better protective efficacy, though there was no statistical significance. The disappearance rate of dysplasia was 82.8% in the Moluodan group, which was superior to folic acid (53.9%; P = 0.006). No drug‐related serious adverse events were observed. Conclusions: One pack of Moluodan three times daily for 1 year was safe and effective in reversing gastric precancerous lesions, especially dysplasia. Doubling its dose showed a better efficacy trend. [ABSTRACT FROM AUTHOR]

Objective: This pilot study aimed to evaluate the efficacy and safety of domperidone for the treatment of Chinese patients with functional dyspepsia (FD) who were diagnosed according to the Rome IV criteria and to identify the FD subtypes that potentially responded better to domperidone. Methods: This multicenter prospective study was conducted in China from August 2018 to July 2020, consisting of a 1‐week screening phase and a 2‐week double‐blind treatment phase. Participants were randomized to receive domperidone 10 mg or matching placebo tablets thrice daily for 14 days. The primary end‐point was the overall treatment effect (OTE) response rate after 2‐week therapy. Results: Altogether 160 patients were included, with 80 patients in each group. The OTE response rate after 2‐week therapy was significantly higher for domperidone compared with placebo (60.7% vs 46.0%; relative risk [RR] 1.318, 95% confidence interval [CI] 0.972–1.787). Moreover, the OTE response rate after 2‐week domperidone or placebo treatment was 60.3% versus 54.9% for postprandial distress syndrome (PDS) (RR 1.098, 95% CI 0.750–1.607) and 60.6% versus 35.2% for overlapping PDS–epigastric pain syndrome (EPS) (RR 1.722, 95% CI 0.995–2.980). Adverse events were reported by seven patients in the domperidone group and 12 patients in the placebo group. None of the adverse events in the domperidone group were serious. Conclusion: Domperidone showed a positive pattern regarding OTE response rates after 2‐week therapy compared to placebo in patients with FD, as well as in subtypes of PDS and overlapping PDS–EPS. No new safety issue was observed. [ABSTRACT FROM AUTHOR]

Flutter is an instability phenomenon that can occur in wind turbine blades due to fluid–structure interaction, particularly for longer and more flexible blades. Aeroelastic tailoring through bend–twist coupling is an effective method to enhance the aeroelastic performance of blades. In this study, we investigate the impact of bend–twist coupling on the structural performance and flutter limit of the IEA 15 MW blade, which is currently the longest reference wind turbine blade, and determine the optimal layup configuration that maximizes the flutter speed. The blade is modeled by NuMAD and iVABS, and the cross-section properties are obtained by PreComb and VABS. The accuracy of the blade model is verified in terms of stiffness and frequency. The bend–twist coupling is implemented by changing the fiber angle of the skin and spar cap considering symmetric and asymmetric layups. The flutter limits of both the baseline and the bend–twist coupled blade are evaluated based on HAWC2. The results show that the angle of spar cap carbon fiber has a greater effect on the blade's structural properties and flutter speed than the skin fiber. Varying the spar cap carbon fiber angle increases the flutter speed, with the effect being more significant for the symmetric layup, up to 9.66% at a fiber angle of 25 degrees. In contrast, the variation in skin fiber angle has a relatively small impact on flutter speed—within ±3%. [ABSTRACT FROM AUTHOR]

Wind power, as an eco-friendly renewable energy, has been widely integrated into modern power systems. The prediction accuracy of wind power is crucial to the secure operation of power systems. To improve the prediction accuracy, a hybrid hour-ahead wind power prediction method is presented in this paper. First, the variational mode decomposition (VMD) is used to decompose the original wind power sequences into a set of intrinsic mode functions (IMFs) with different frequencies. Then, the prediction model is formulated by using the long short-term memory (LSTM) network for each IMF. To enhance the LSTM, a bio-inspired algorithm named Harris Hawks optimization (HHO) is blended to optimize the parameters of each LSTM prediction model. The final prediction output power is thus obtained by integrating all prediction results from these individual IMFs, so that the novel VMD–HHO–LSTM prediction strategy is developed. Finally, case studies based on the real historical dataset are performed, demonstrating that the proposed hybrid hour-ahead wind power prediction model named VMD–HHO–LSTM has better prediction performance and higher applicability to multiple dataset scenarios. [ABSTRACT FROM AUTHOR]