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The loss of synchronization (LOS) is a main issue for dynamic behavior of grid-following converter (GFC) under inductive power grid. This letter reveals the underlying mechanism of insufficient damping or even negative damping during grid disturbance, and analyzes how the initial speed of angle-difference between PLL output and grid voltage affects the synchronization stability. Then a synchronization stability enhancement scheme to add a positive damping and a reverse angular frequency during transient process is proposed in this letter.

Fine calculation of bridge temperature fields is significant for accurately evaluating thermal actions in bridge structures. Determining thermal loads on bridge surfaces caused by solar radiation is the most challenging part of the numerical thermal analysis because the sunlit and shaded areas on bridge surfaces change continuously with the sun’s rotation. Existing methods have low accuracy in determining thermal loads and cannot be applied to complex bridges. This study presents a new method for calculating temperature fields based on the advantages of building information modeling (BIM) technology in solar radiation analysis (SRA) and information sharing. This method starts with obtaining an accurate hourly insolation distribution on bridge surfaces through SRA implemented in a BIM system. Then, a Python script seamlessly maps the insolation information to finite element surfaces as thermal loads. This paper details the new method’s implementation steps and technical details, and a practical application on a concrete box girder demonstrates its applicability and effectiveness. Compared with previous methods, the proposed method has significant advantages, such as a more accurate calculation for solar radiation, a lower technical threshold, a higher degree of automation, less computational time, and easier finite element modeling.

Allergic rhinitis (AR) is a common atopic problem in which immune response to the envi-ronmental factors leads to clinical symptoms. Helicobacter pylori neutrophil-activating protein (HP-NAP) as a peptide attenuates Th2 response and stimulates Th1 activation and mucus adhesion promoting protein (MapA) as a cell-surface protein binds to mucus. This study evaluated the effect of HP-NAP and MapA conjugated with alumina nanoparticle on AR. HP-NAP and HP-NAP with MapA were conjugated to alumina nanoparticle and two separate nanopar-ticles were produced. The AR mice were treated with these and HP-NAP in peptide form. The AR symptoms, gene expression of mucus, levels of IL-33 and IL-4, and total and ovalbumin (OVA)-specific IgE levels were evaluated. Nasal rubbing, sneezing, gene expression of mucus, and IL-33 and IL-4 levels, and OVA-specific and total IgE were decreased in three treated groups compared to AR, and there was a significant decrease in the symptoms in AR-H-M-A group (P < 0.05) when compared to the other treated groups. HP-NAP has a controlling effect on AR, and in nanoparticle-conjugated form it can strongly attach to the airway’s mucus via MapA. Therefore, cooperation of HP-NAP-alumina with MapA can produce an effective and applicable treatment for AR.

The dynamic response characteristics of the tunnel and the stability of the surrounding rock are crucial to its safety of the tunnel. Combining the numerical simulation software and field measurement results, the change of peak particle vibration (PPV) and stress were analyzed, based on the longitudinal wave data from the acoustic tests, the blasting damage effects under the action of different blasting counts, including different locations in the deep part of the surrounding rock, were investigated. The results show that: (1) in the vertical direction of the tunnel, the PPV of the tunnel floor and tunnel sidewall is larger, the PPV of the tunnel top is the second, and the tunnel arch shoulder and arch foot is the smallest; (2) under the action of blasting, the stress concentration at the tunnel bottom and arch foot is easier, and the stress monitoring should be strengthened; (3) The depth of damage at different distances was 1.5 m and 3.0 m, respectively, and the depth of damage to the surrounding rock increased from 2.5 m to 4.0 m when the number of blasts was 10 and the number of blasts was 10.

The properties of the combustion and deflagration to detonation transition (DDT) of Al/Fe2O3/RDX hybrid nanocomposites, a type of potentially novel lead-free primary explosives, were tested in weakly confined conditions, and the interaction of Al/Fe2O3 nanothermite and RDX in the DDT process was studied in detail. Results show that the amount of the Al/Fe2O3 nanothermite has a great effect on the DDT properties of Al/Fe2O3/RDX nanocomposites. The addition of Al/Fe2O3 nanothermite to RDX apparently improves the firing properties of RDX. A small amount of Al/Fe2O3 nanothermite greatly increases the initial combustion velocity of Al/Fe2O3/RDX nanocomposites, accelerating their DDT process. When the contents of Al/Fe2O3 nanothermite are less than 20 wt%, the DDT mechanisms of Al/Fe2O3/RDX nanocomposites follow the distinct abrupt mode, and are consistent with that of RDX, though their DDT processes are different. The RDX added into the Al/Fe2O3 nanothermite increases the latter's peak combustion velocity and makes it generate the DDT when the RDX content is at least 10 wt%. RDX plays a key role in the shock compressive combustion, the formation and the properties of the DDT in the flame propagation of nanocomposites. Compared with RDX, the fast DDT of Al/Fe2O3/RDX nanocomposites could be obtained by adjusting the chemical constituents of nanocomposites.

Previously 47 genera of the subfamily Phaneropterinae were recorded from China, not including the genus Himertula Uvarov, 1940. Here, Himertula Uvarov, 1940 is reported in China for the first time, adding a new species H. gyirongensis sp. nov., specimens of which were collected in Tibet, China. Illustrations and habitat images are provided. The distribution of Himertula species is also discussed and mapped. The types are deposited in Insect Collection of Institute of Zoology, Chinese Academy of Sciences, Beijing, China (IZCAS).

We are in a golden age of progress in artificial intelligence (AI). Radiotherapy, due to its technology-intensive nature as well as direct human-machine interactions, is perfectly suited for benefitting from AI to enhance accuracy and efficiency. Over the past few years, a vast majority of AI research have already been published in the field of photon therapy, while the applications of AI specifically targeted for particle therapy remain scarcely investigated. There are two distinct differences between photon therapy and particle therapy: beam interaction physics (photons vs. charged particles) and beam delivery mode (e.g. IMRT/VMAT vs. pencil beam scanning). As a result, different strategies of AI deployment are required between these two radiotherapy modalities. In this article, we aim to present a comprehensive survey of recent literatures exclusively focusing on AI-powered particle therapy. Six major aspects are included: treatment planning, dose calculation, range and dose verification, image guidance, quality assurance and adaptive replanning. A number of perspectives as well as potential challenges and common pitfalls, are also discussed.

Breast cancer is one of the most common and disastrous neoplasm for women worldwide, especially triple-negative breast cancer (TNBC). Emerging evidences have demonstrated that RNase subunits are closely related to the occurrence and development of malignant tumors. However, the functions and underlying molecular mechanisms of Processing of Precursor 1 (POP1), a core component of RNase subunits, in breast cancer development have not been fully defined. Our study identified the POP1was upregulated in breast cancer cell lines and tissues and patients with higher POP1 expression were associated with poor outcomes. Overexpression of POP1 promoted cell progression in breast cancer cells, whereas silencing of POP1 induced cell cycle arrest. Moreover, Xenograft model reproduced its growth regulatory roles in breast cancer in vivo. Mechanistically, POP1 interacted and activated the telomerase complex by stabilizing the telomerase RNA component (TERC), thus protecting telomeres from shortening during division. Collectively, our findings demonstrate POP1 may as a novel prognostic marker and a therapeutic target for the management of breast cancer.

In this paper, we focus on the need for measuring the intelligibility of English pronunciation using an automated speech system, and the system proceeded in this feasibility study was tested with 18 speakers coming from six countries representing six types of English (China, Vietnam, Egypt, India, South Africa and the Philippines). Those test candidates were selected carefully to stand for a series of intelligibility, two different approaches, transcription and nonsense, were utilized to test and measure their intelligibility. An automated computer pattern developed for speaking proficiency scoring based on suprasegmental measures was set to predict intelligibility scores. The Pearson’s correlation was 0.743 for transcription construct and 0.819 for the nonsense construct between the human assessed and computer predicted scores. The reliable inter-rater Cronbach’s alpha for the transcription scores was 0.943 and 0.945 for the nonsense intelligibility scores. Basing on the type of intelligibility measure, the computer utilized different suprasegmental measures to predict the score. The computer used 11 measures for the nonsense intelligibility score and eight for the transcription score. Only two features were common to both constructs. These analyses and results of this computer experimental pattern can provide researchers of L2 different perspectives of measuring intelligibility in research afterwards.

This study aimed to evaluate the effects of exercise cognitive combined training (ECCT) compared with non-ECCT on physical function in cognitively healthy older adults. Databases were searched for randomized controlled trials from inception to December 2, 2021, and 22 studies (1,091 participants, Mage = 74.90) were included in the meta-review. The Cochrane Risk of Bias and Grading of Recommendations Assessment, Development, and Evaluation tools were used for quality assessments. ECCT improved gait speed (mean difference: 0.06 m/s, 95% CI [confidence interval] [0.02, 0.11]; 446 participants, 11 studies) and balance (standardized mean difference: 0.38, 95% CI [0.14, 0.61]; 292 participants, seven studies). Simultaneous ECCT, but not nonsimultaneous ECCT, improved gait speed (mean difference: 0.11 m/s, 95% CI [0.07, 0.15]), balance (standardized mean difference: 0.40, 95% CI [0.16, 0.64]), and functional mobility (mean difference: −0.85 s, 95% CI [−1.63, −0.07]; 327 participants, nine studies). Future research should focus on the duration and form of ECCT intervention optimal for improving the functional activities of older individuals.

The SARS-CoV-2 Omicron variant has demonstrated enhanced transmissibility and escape of vaccine-derived immunity. Although first-generation vaccines remain effective against severe disease and death, robust evidence on vaccine effectiveness (VE) against all Omicron infections, irrespective of symptoms, remains sparse. We used a community-wide serosurvey with 5,310 subjects to estimate how vaccination histories modulated risk of infection in infection-naive Hong Kong during a large wave of Omicron BA.2 epidemic in January–July 2022. We estimated that Omicron infected 45% (41–48%) of the local population. Three and four doses of BNT162b2 or CoronaVac were effective against Omicron infection 7 days after vaccination (VE of 48% (95% credible interval 34–64%) and 69% (46–98%) for three and four doses of BNT162b2, respectively; VE of 30% (1–66%) and 56% (6–97%) for three and four doses of CoronaVac, respectively). At 100 days after immunization, VE waned to 26% (7–41%) and 35% (10–71%) for three and four doses of BNT162b2, and to 6% (0–29%) and 11% (0–54%) for three and four doses of CoronaVac. The rapid waning of VE against infection conferred by first-generation vaccines and an increasingly complex viral evolutionary landscape highlight the necessity for rapidly deploying updated vaccines followed by vigilant monitoring of VE.