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High proportion of wind power generation weakens the power system inertia, causing concerns over frequency stability. The direct-drive permanent magnet synchronous generators-based wind turbine system (WTS) usually uses virtual inertia control (VIC) to support frequency. However, the related controller parameters are difficult to design, and the deep participation in frequency regulation (FR) will reduce the economic benefits of WTS. To this end, this paper breaks out of the VIC framework, and proposes a transient FR strategy based on frequency trajectory planning (FTP). The basic idea is to actively plan a frequency trajectory with a safety margin according to the grid frequency threshold when the system is disturbed, so that the FR power provided by the WTS can be controlled according to the planned frequency trajectory and achieve rapid support for the system transient frequency, ensuring the safe and stable operation of the grid while achieving the economy of wind power generation. Simulation and hardware-in-loop experimental results demonstrate that the proposed FTP-based transient FR strategy for WTS is effective and economical.

Although it has been reported that superoxide dismutase (SOD) is related to obstructive sleep apnea (OSA), the results are controversial. In addition, the effects of the continuous positive airway pressure (CPAP) treatment on SOD levels are also inconsistent. The primary purpose of the present meta-analysis is to determine the relationship between the circulating SOD levels and OSA. The studies included in this meta-analysis were selected from the PubMed, Embase, Cochrane Library, and Scopus databases. Two researchers independently reviewed the studies. Data analysis was performed using Stata 15.1. The overall effects were measured using the standardized mean difference (SMD) with a 95% confidence interval (CI). A random-effects model or a fixed-effects model was used, depending on the heterogeneity of the studies. A total of 14 studies were included, comprising 1240 patients and 457 controls. The results showed that the circulating SOD levels of the patients with OSA were significantly lower than that of the control group (SMD = − 1.645, 95% CI = − 2.279 to − 1.011, P

Rice breeders are now developing new varieties with semi-high or even high plant height to further increase the grain yield, and the problem of lodging has re-appeared. We identified a major quantitative trait locus (QTL)

The interrelationship between regional water, energy, food, and land systems is extremely complex. Hence, accurately assessing the coupling coordination relationship and identifying the influential factors of the water-energy-food-land nexus (WEFL nexus) are of utmost importance. This study proposes a novel analytical framework and evaluation index system for exploring interactions across the WEFL nexus. The comprehensive benefit evaluation index (CBEI), coupling coordination degree (CCD) model, and obstacle factor diagnosis model are integrated to assess and analyze the coupling coordination relationship and spatiotemporal dynamic evolution of the WEFL nexus in the Yangtze River Economic Belt (YREB) from 2006 to 2020. The results indicated that (1) the CBEI and CCD generally increased from 0.23 to 0.79 and 0.45 to 0.88, respectively, revealing the upward trend of the coordination development levels of the WEFL nexus in the YREB. (2) The lower reaches achieved a relatively higher coordination development degree than the upper and middle reaches of the YREB. (3) The findings of obstacle factors reveal that agricultural non-point source pollution control, waterlogging disaster prevention, industrial solid waste efficient treatment, and urban water-saving are the essential fields that need to be improved in YREB's future development. This study helps to understand the complex interrelation of the WEFL nexus at different spatial-temporal scales and provides a novel framework that can be used as an evaluation system and policy insights for a region's integrated resources, environmental management, and green sustainable development.

Recent studies indicate that Alzheimer's disease- (AD) related biomarkers, including amyloid β (Aβ40 and Aβ42) and tau proteins (P-tau and T-tau), in blood and cerebrospinal fluid (CSF) are associated with obstructive sleep apnea (OSA). However, the results have been inconsistent. Therefore, the primary purpose of this meta-analysis was to determine the relationship between blood and CSF AD-related biomarkers and OSA.We searched the Embase, PubMed, Scopus, and Cochrane Library databases for relevant articles till February 2022.Eight articles were finally included after the literature screening, including 446 patients with OSA and 286 controls. Pooled analysis showed that CSF Aβ42 (SMD = -0.220, P = 0.136), T-tau (SMD = 0.012, P = 0.89), and P-tau (SMD = 0.099, P = 0.274) levels were not different between patients with OSA and controls. In patients with moderate to severe OSA, CSF Aβ42 (SMD = -0.482, P = 0.031) were significantly lower than in controls. Blood T-tau (SMD = 0.560, P = 0.026), P-tau (SMD = 0.621, P 0.001), and Aβ40 (SMD = 0.656, P 0.001) levels were significantly higher in patients with OSA than in controls. Blood Aβ42 (SMD = 0.241, P = 0.232) were not different between patients with OSA and controls.OSA is associated with changes in AD-related markers. Higher OSA severity may be associated with the development of AD. AD-related biomarkers, especially in the blood, are clinically efficient, less invasively assessed and monitored, and may be useful for detecting OSA and related cognitive impairments. Further studies are needed to confirm these results.

Fast and accurate acquisition of voltage components is the basic requirement for grid-tied inverters to realize various control under unbalanced grids. In view of this situation, a delay sampling period filter, which rapidly separates each voltage component by delaying two sampling periods in dq frame, is proposed in this article. In view of the noise interference, a delay operation period filter (DOPF) is proposed to scale the operation period and limit the noise to an acceptable range. The complete positive sequence components (PSC) extraction method based on the developed DOPF+ moving average filter (MAF) algorithm is presented, combing the advantages of DOPF and MAF for eliminating the double-frequency ac components and high-frequency noise, respectively. Finally, the feasibility and priority of the DOPF+MAF algorithm and PSC extraction method have been verified by the physical experimental results.

Sensoryneuronal hearing loss (SNHL) is one type of hearing impairment. The incidence of hearing loss (HL) is 1–3 per 1000 births. Complementary therapies may be effective in addressing the maladies of infants with HL. The aim of this study was to assess the efficacy of foot reflexotherapy in an infant with SNHL. The patient was a 3-month-old infant with SNHL. Pretest and post-test for HL were conducted using an audiologic method (auditory brainstem responses) combined with behavioral audiometry. The subject was treated with foot reflexotherapy for 30 min per session four times per week for a period of 24 weeks. Foot reflexotherapy was effective in auditory recuperation of an infant with SNHL. The results of this novel study suggest that foot reflexotherapy can be an effective complementary treatment for infants with SNHL, especially for those 3 to 9 months of age.

For physically understanding the dynamic response of the photovoltaic (PV) integrated power system for electromechanical oscillations damping, firstly, this paper develops the linear mathematical model of a single machine infinite bus system integrated by the PV grid-tied inverter under the electromechanical time scale. Then, based on the electric torque analysis method, and the functional route of the PV grid-tied inverter variable active power control (P-control) and reactive power control (Q-control) with the power angle or grid frequency feedback as the input control signal, the key factors and influence laws of the integrated system inertia, damping level and synchronization capability are investigated. The developed model shows that enlarging the proportional-integral-derivative (PID) controller parameters of P and/or Q-control loop can effectively change electromagnetic power distribution to suppress the imbalance power, and equivalently improve the system damping level, synchronization capability and inertial effect, respectively, contributing to actively adjust the grid frequency oscillation amplitude, period and recovery speed to maintain the system control stability according to the grid code demand. Besides, under the same inverter capacity constraint, P-control mode is proved more advantageous than Q-control mode to damp electromechanical oscillations. Finally, the correctness of the physical mechanism analysis is verified by MATLAB simulations and RT-LAB experiments.

Rice breeders are now developing new varieties with semi-high or even high plant height to further increase the grain yield, and the problem of lodging has re-appeared. We identified a major quantitative trait locus (QTL), qSCM4, for resistance to lodging by using an F2 segregant population and a recombinant self-incompatible line population from the cross between Shennong265 (SN265) and Lijiangxintuanheigu (LTH) after multiple years and multiple environments. Then, the residual heterozygous derived segregant population which consisted of 1781 individual plants, and the BC3F2 segregant population which consisted of 3216 individual plants, were used to shorten the physical interval of qSCM4 to 58.5 kb including 11 genes. DNA sequencing revealed the most likely candidate gene for qSCM4 was Os04g0615000, which encoded a functional protein with structural domains of serine and cysteine. There were 13 DNA sequence changes in LTH compared to SN265 in this gene, including a fragment deletion, two base changes in the 3′ UTR region, six base changes in the exons, and four base changes in the introns. A near-isogenic line carrying qSCM4 showed that it improved the lodging resistance through increasing stem thickness by 25.3% and increasing stem folding resistance by 20.3%. Furthermore, it was also discovered that qSCM4 enhanced the primary branch per panicle by 16.7%, secondary branch by per panicle 9.9%, and grain number per panicle by 14.7%. All the above results will give us a valuable genetic resource for concurrently boosting culm strength and lodging resistance, and they will also provide a basis for further research on the lodging resistance mechanism of rice.

Background In aminoglycoside-induced hearing loss, damage to spiral ganglion neurons (SGNs) accelerates gradually after the acute outer hair cell death, accompanied by macrophage infiltration and cytokine release. Pyroptosis plays a critical role in neurodegenerative diseases. Here, we explored the potential role of pyroptosis in SGN degeneration. Methods C57BL/6J mice were randomly divided into a kanamycin plus furosemide group and saline control group. Auditory functions were evaluated by auditory brainstem response tests conducted before treatment and at 1, 5, 15, and 30 days after treatment. HCs and SGNs were assessed for morphological alterations. SGNs were subjected to RNA sequencing and mRNA and protein analyses of NLRP3 inflammasome-related molecules. Macrophage activation was evaluated based on morphological and mRNA alterations. The effect of NLRP3 inhibition on SGN survival after kanamycin treatment was evaluated in organ explant cultures treated with Mcc950, a specific inhibitor of the NLRP3 inflammasome. Results Kanamycin and furosemide administration led to irreversible deterioration of the auditory brainstem response threshold, accompanied by acute loss of outer hair cells and gradually progressive loss of inner hair cells. SGNs showed a progressive decrease in quantity, as well as swelling and membrane rupture, at 15 and 30 days. RNA sequencing of SGNs showed that inflammation and immune-related responses were significantly upregulated, as was the expression of the inflammasome-related gene NLRP3. During 30 days of kanamycin exposure, the canonical pyroptosis pathway was constantly activated in SGNs. Activation and infiltration of microglia-like cells/macrophages, and increased production of cytokines, hallmarks of neuroinflammation, were also observed. Mcc950 significantly ameliorated SGN degeneration by inhibiting NLRP3 expression and promoting release of interleukins 1β and 18. Conclusions Pyroptosis causes cell death during aminoglycoside-induced SGN degeneration. Activation of the NLRP3 inflammasome leads to a cascade of inflammatory events in SGNs. Inhibition of the NLRP3 inflammasome significantly alleviates SGN damage, suggesting that it could serve as a new molecular target for the treatment of aminoglycoside-induced SGN degeneration.

This paper uses Chinese firm-level data from 2001 to 2007 and applies a propensity score matching method combined with a difference-in-differences approach to examine the direct causal link between inward foreign direct investment (FDI) and various aspects of Chinese firms’ performance. We divide China into four economic regions and subdivide the origin of foreign investment into HMT investment (within the Greater China Area) and other foreign investment (outside the Greater China Area). The results indicate that the progress of the IFDI market in China is not evenly balanced within the four economic regions, while the different origins of foreign investment produce different effects.

As delayed diagnosis and treatment of cerebrospinal fluid (CSF) leakage are common in current practice, this study was performed to determine associated factors and discuss appropriate strategies to deal with these problems. A retrospective analysis of all cases of CSF leakage in our hospital from 2007 to 2018, including 41 patients with CSF rhinorrhea and 5 with CSF otorhinorrhea, was performed. Symptoms, associated diseases, misdiagnoses, history of skull base repair surgical, previous medical costs, and number of hospital visits before visiting our institution were reviewed. The diagnoses, surgical reconstruction methods, and prognoses of the patients were analyzed. In 18 patients, CSF leakage was spontaneous, in 14 the cause was trauma, and in the remaining 14 the origin was iatrogenic. Twelve patients had been misdiagnosed with allergic rhinitis, rhinosinusitis, or otitis media. Twelve cases had intracranial infection and 14 suffered airway infection. Six had undergone unsuccessful craniotomy, endonasal endoscopic surgery, or ear surgery for treatment of CSF leakage before visiting our institute. This resulted in an average of 5.13 ± 1.32 referrals and medical costs of up to 20,795.7 ± 4553.80 RMB. The success rate was 97.83% after repairing CSF fistulae in our hospital. The septal floor flap (SFF) method (based on ethmoidal arteries) to treat CSF rhinorrhea showed a success rate of 100% in 12 patients. Therefore, early localization, clinical diagnosis, and appropriate repair surgery can avoid the occurrence of delayed events. Pedicled flaps, including SFF, are recommended to manage challenging CSF rhinorrhea.

To solve the frequency problem caused by high wind power penetration, control strategies such as rapid power compensation (RPC) have been adopted to release the frequency regulation capability of new energy sources quickly. However, when the wind turbine (WT) adopts the RPC strategy to participate in the system frequency regulation, it cannot adapt to the random disturbance. In this paper, a disturbance adaptive RPC (ARPC) strategy is proposed. When the system is disturbed, the signal excitation method is used to estimate the external disturbance. According to the estimated disturbance, the WT rotational inertia is quickly used to compensate for the grid's unbalanced power. When the system frequency deviation and the rate of change of frequency (RoCoF) evaluation indexes meet the threshold requirements, the control strategy switches from ARPC to droop control, which can ensure the WT exit frequency regulation smoothly, and further reduce the frequency deviation and improve the frequency quality. Finally, analyzing the operation mode and determining the relevant switching logic, the proposed ARPC strategy's detailed implementation is developed. Simulation results proved the effectiveness and advancement of the ARPC based strategy.

To reveal the inertia and damping characteristics of the electric vehicle system considering Phase Locked Loop (PLL), the research object of this paper is the two-stage electric vehicle system based on DC droop control. Based on the static synchronous generator model, the main parameters which affect the inertia level and damping effect of the electric vehicle system are analyzed. The results show that the frequency control loop, power control loop and constant voltage control loop are the main sources of inertia effect and damping effect of the system. The inertia and damping characteristics of the system can be changed by optimizing the control parameters. Adjusting the parameters of PLL in the strong power network can change the inertia and damping characteristics of the disturbance on the grid side, but it cannot change the dynamic characteristics of the energy side oscillation. The simulation results prove the correctness of the research conclusions. The conclusions of this paper are beneficial to the design of control strategy for electric vehicle system, and can also help to improve the inertia level and damping capacity of power grids.

Transportation infrastructure, which has always been regarded as an important element to promote regional innovation, accelerates factor flows and productivity spillovers. In February 2021, the State Council of China issued the outline of national integrated multidimensional transportation network planning (2021–2050), which proposed that during the 14th Five-Year Plan period, the Yangtze River Delta would speed up the construction of an integrated transport network to serve the dual circulation development pattern in China. However, few studies have systematically investigated the development of integrated transport in the Yangtze River Delta, especially the relationship between transport operating efficiency and regional innovation based on the theory of flow space. This study aims to calculate the integrated transport efficiency of 26 cities in the Yangtze River Delta and analyse the spillover effect of efficiency improvement on urban innovation. The results reveal that integrated transport efficiency is relatively stable at approximately 0.92. We find that the local innovation value would increase by 0.119% with every 1% increase in transport efficiency, and it would exceed 0.26% after introducing spatial factors. The spillover effect on the surrounding cities is significantly higher than that in the cities themselves, and the result is 0.292 under the economic spatial distance weight matrix. These findings will support the construction of the integrated transport network and provide useful references for government decision makers in the Yangtze River Delta.

A variety of inflammatory cells are infiltrated histologically in sinonasal mucosa of chronic rhinosinusitis with nasal polyps (CRSwNP), especially CRSwNP with asthma. Acid-sensing ion channel 1a (ASIC1a) is essential in the process of sensing acidification and triggering inflammation. Whereas, its role and mechanism in CRSwNP remain uncertain. The present study aimed to explore the roles and mechanism of ASIC1a in the pathogenesis of CRSwNP. Nasal secretions from control subjects, patients with CRSwNP with or without asthma were collected for measuring pH values. Western blotting, real-time PCR and immunohistochemistry (IHC) were employed to assess ASIC1a expression in nasal tissue samples from included subjects. The co-localization of ASIC1a with inflammatory cells was evaluated by immunofluorescence staining. Then, dispersed nasal polyp cells (DNPCs) were cultured under acidified condition (pH 6.0), with or without ASIC1a inhibitor amiloride. Western blotting, real-time PCR, LDH activity kit, and ELISA were performed to assess the effects and mechanisms of stimulators on the cells. The pH values were significantly lower in the nasal secretions from patients with CRSwNP with asthma. Significant upregulation of ASIC1a protein, mRNA levels, and positive cells was found in CRSwNP with asthma. ASIC1a was detected in a variety of inflammatory cells. In cultured DNPCs, significant alterations of ASIC1a levels, LDH activity, HIF-1α levels, and inflammatory cytokines were found under acidified condition (pH 6.0), but were prevented by amiloride. Upregulation of ASIC1a might be essential in the process of sensing acidification and triggering inflammatory response via enhancing HIF-1α expression and LDH activity to activate inflammatory cells in the pathogenesis of CRSwNP, especially in CRSwNP with asthma.

Background Oxidative stress plays crucial roles in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). Thioredoxin-interacting protein (TXNIP) is essential in the process of triggering oxidative stress. However, its role and mechanism in CRSwNP remain unclear. The present study sought to explore the role and mechanism of TXNIP in the pathogenesis of CRSwNP. Methods Western blotting, real-time PCR and immunohistochemistry (IHC) were employed to assess TXNIP, thioredoxin (TRX) expression in nasal tissue samples from patients with CRSwNP and control subjects. MDA level and SOD activity in nasal tissue homogenates were measured using MDA and SOD Assay Kit. To evaluate the role and mechanism of TXNIP in CRSwNP, human nasal epithelial cells (HNECs) were cultured and stimulated using TXNIP siRNA, with or without N-acetylcysteine (NAC, an ROS scavenger). Western blotting, real-time PCR, ROS detecting dye DCFH-DA, MDA and SOD Assay Kit were performed to assess the effects and mechanisms of stimulators on the cells. Results We found significantly increased levels of TXNIP and decreased levels of TRX protein, mRNA, positive cells, increased MDA level and decreased SOD activity in CRSwNP patients compared with control subjects. In vitro study, significantly altered levels of TXNIP, TRX, MDA, SOD and ROS in HNECs were found following treatment of TXNIP siRNA with or without NAC on HNECs. Conclusion TXNIP expression was increased and TRX expression was decreased in CRSwNP at both protein and mRNA levels. MDA levels were increased and SOD activities were decreased in CRSwNP. TXNIP may have negative association with TRX, and then decrease SOD activities and increase MDA levels, resulting in the upregulation of ROS and oxidative stress in HNECs, which may play a pivotal role in the pathogenesis of CRSwNP. Future studies are expected to further explore the role and mechanism of TXNIP in CRSwNP.

By modulating the active power output of the grid-tied inverter, the photovoltaic (PV) generation system can effectively damp the electromechanical oscillation of the power grid. To analyze the influence of different PD controller gains on its output power for the typical droop and inertia control strategies, this paper takes the conventional application scenarios of PV damping electromechanical oscillation as the research example. Studies show that when the PD controller gain is amplified to the limit condition, the PV generation system will operate in the rapid power compensation (RPC) mode: based on the speed deviation polarity, the active power modulation limit (Pmppt or 0) will be used as the basis for alternate output to damp the system imbalanced power. The comparison of speed indicators shows that the RPC mode is significantly stronger than the conventional droop and inertia control for grid electromechanical oscillation damping. In view of this, this paper proposes a novel grid electromechanical oscillation damping strategy based on RPC mode, and sets the switching thresholds and corresponding active current commands for 4 operating conditions to quickly and effectively suppress the generator rotor speed oscillation phenomenon. The simulation results show that the proposed control strategy in this paper does not require a complicated control parameter tuning process, and can significantly suppress the system electromechanical oscillation, which is beneficial to ensure the power system stable operation.

The grid connection of large-scale wind power will reduce the equivalent inertia and damping of the system, resulting in a decrease in system frequency stability. The directly-driven permanent magnet synchronous generators (D-PMSG)-based wind turbine (WT) usually uses conventional PD control to support frequency, however, the related controller parameters are difficult to design, reducing economic benefits of WT power generation and slowing speed recovery. To this end, based on the analysis of the dynamic response of D-PMSG grid-tied system, this paper studies the dynamic influence and variation law of controller parameters on system frequency. A WT control strategy based on frequency trajectory planning (FTP) is proposed. The frequency fixed value determined by the power grid regulation is directly taken as the control target to carry out the FTP, and the WT auxiliary power output is controlled according to the planned frequency trajectory. The system frequency is supported quickly in the transient process, ensuring the safe and stable operation of the grid while realizing the economy of WT power generation. The effectiveness and economy of the proposed control strategy is verified by RT-LAB experiment.

Background Allergic rhinitis (AR) is a type I hypersensitivity mediated by IgE in the nose. Thioredoxin-interacting protein (TXNIP) plays a pivotal role in the process of producing reactive oxygen species (ROS). Resveratrol is a TXNIP inhibitor. Nonetheless, its role and mechanism in AR are still undetermined. The present study aimed to explore the effect and mechanism of resveratrol on an ovalbumin (OVA) induced mouse model of AR. Methods AR murine model was established using OVA and administrated intranasally with resveratrol or N-acetylcysteine (NAC). Hematoxylin and eosin (HE) stain was used for evaluating eosinophils. Immunohistochemistry (IHC) staining and real-time PCR were employed to evaluate immunolabeling and mRNA expression of TXNIP in nasal mucosas of mice. Malondialdehyde (MDA) level and superoxide dismutase (SOD) activity in nasal tissue homogenates were measured using MDA and SOD Assay Kit. Concentrations of OVA-specific IgE and histamines in serum, and OVA-specific IgE, PGD2, LTC4, ECP, IL-4, IL-5, IL-6, IL-33 and TNF-α in nasal lavage fluid (NLF) were assayed by ELISA. In vitro studies, western blotting, real-time PCR, ELISA, ROS detecting dye DCFH-DA, MDA, and SOD Assay Kit were performed to evaluate the effects and mechanisms of OVA, resveratrol or NAC on spleen mononuclear cells. Results We found significant alternations of sneezing, nasal rubbing, inflammatory cytokines, eosinophil numbers, TXNIP, MDA, and SOD levels in resveratrol or NAC treated mice compared with untreated AR mice. In cultured spleen mononuclear cells, TXNIP, MDA, SOD, ROS and inflammatory cytokines levels were altered by OVA but reversed by resveratrol or NAC. Conclusions Resveratrol could effectively alleviate murine AR by inhibiting TXNIP-oxidative stress pathway.

BACKGROUND: Follicular dendritic cell (FDC) sarcoma is a neoplastic proliferation of spindled to ovoid cells showing morphological and immunophenotypic features of FDCs. Inflammatory pseudotumor-like follicular dendritic cell sarcoma（IPT-FDCS）involves almost exclusively in the liver and spleen and are consistently associated with Epstein-Barr virus (EBV).Rarely, it selectively involves the gastrointestinal tract in the form of a polypoid lesion.CASE SUMMARY: We report two cases of IPT-FDCS mimicking a colonic polyp that received high frequency electrocoagulation separately.The patients’main concern were whether to have chemotherapy or radiation after removal.After many consultations and literature review,The patients were treated by surgical resection, without adjuvant chemotherapy or radiation. Follow-up for 32 months showed no recurrence or metastasis.RESULTS: The neoplasms usually had well—defined borders，composed of the neoplastic spindled cells are dispersed within a prominent lymphoplasmacytic infiltrate. The nuclei usually show a vesicular chromatin pattern and small but distinct nucleoli. Immunohistochemically，tumor cells showed the expression of at least one of the FDC markers，including CD21,CD35, CD23 and D2-40，with scattered positive EBER in situ hybridization.CONCLUSION: IPT-FDCS could rarelly occur in the intestine with a polypoid appearance. Recognization of this disease could avoid being misdiagnosed as other common types of colonic polyposis. EBV-encoded mRNA (EBER) by in situ hybridization and FDC-related immunohistochemical markers plays an important role in differential diagnosis.

The measurement accuracy and rapidity of phase detection block are the crucial factors for the higher performance control of grid-connected converters under high-frequency noise condition. Open-loop phase detection (OPD) in the dq frame is characterized by fast grid synchronization, but its noise immunity has been unevaluated quantitatively, including interference principle and influence law of phase accuracy. To remedy this problem, a detailed noise immunity analysis model is developed in this paper, which shows that the OPD behaves different noise immunity when the dq frame is in different positions. In case of the voltage coincides with the d-axis, the noise has the smallest interference on the phase accuracy, and OPD has the strongest noise immunity. On the contrary, when the angle between voltage vector and d axis is close to $\pi$/4, the phase error is the largest. Inspired from this, a novel OPD to improve the phase-measuring accuracy is proposed. By fine-tuning the rotation angle of dq frame, the angle between voltage vector and the d axis is always close to 0, which can enable the phase error to be acceptable. In addition, the enhanced algorithm can reduce the bandwidth requirement of the filter and shorten the dynamic response time in the phase-detecting process. The correctness of the noise immunity analysis and the effectiveness of the improved algorithm are verified by the real-time simulation.

Fast and accurate acquisition of voltage components are the basic requirement for grid-connected inverters to realize various control under unbalanced grids. In view of this situation, a delay sampling period filter (DSPF) algorithm, which rapidly separates each voltage component by delaying two sampling periods of voltage components under dq frame, is proposed. Besides, in view of the noise interference in the grid voltage, a delay operation period filter (DOPF) algorithm is proposed to scale the operation period and limit the noise level to an acceptable range. Finally, the corresponding model is built in MATLAB and physics experiment platform to verify the feasibility and priority of this method.

Patients affected by pulmonary tuberculosis (PTB) manifest deficiencies in innate cellular immunity. The Tim3/Galectin-9 axis is an important regulator of Th1 cell immunity, leading to Th1 cell apoptosis. Herein, this study aims to clarify the underlying roles of the Tim-3/Galectin-9 axis in T-cell immunity in PTB. Peripheral blood mononuclear cells (PBMCs) were extracted from subjects with and without PTB to examine the expression of CD4, CD8, CD25, and Tim-3 under the stimulation of Mycobacterium tuberculosis (MTB) and purified protein derivative (PPD). In addition, the expression of Tim-3 and Galectin-9 in PBMCs was determined. The Tim-3/Galectin-9 axis in the PBMCs was activated or blocked to detect the secreted levels of IFN-γ, TNF-α, IL-2, and IL-22. MTB stimulation increased the expression of CD4, CD8, CD25, Tim-3, and Galectin-9 in PBMCs. The blockade of Tim-3/Galectin-9 axis resulted in reduced secretion of IFN-γ, TNF-α, IL-2, and IL-22 from T-cells. Moreover, Tim-3+CD4+T, Tim-3+CD8+, and Tim-3+CD25+T cells exhibited a greater ability to inhibit the replication of MTB in macrophages. Taken conjointly, the blockade of Tim-3/ Galectin-9 axis inhibits the secretion of inflammatory cytokines in T-cells to regulate the T-cell immunity in PTB.

To improve the noise immunity of a dq frame based open-loop phase detection (OPD) under high-frequency noise grid conditions, this paper develops a detailed model to quantitatively evaluate the phase detection error and noise immunity. It is found that the OPD behaves differently in terms of noise immunity when the dq frame is in different angle positions with the grid voltage. When the grid voltage coincides with the d axis, the high-frequency noise has the smallest impact on the phase detection accuracy, and the OPD thus has the strongest noise immunity. Inspired by this conclusion, an improved OPD algorithm is proposed in this paper, which can effectively reduce the phase detection error by fine-tuning the rotation angle of the dq frame to ensure that the angle between the voltage vector and d axis is always close to 0. The improved OPD algorithm has a fast and precise character to detect the phase information with less error and is flexible for application. Under heavy noise grid conditions, it can also effectively shorten the dynamic response time in the phase-detecting process using a low-pass filter (LPF) with a higher cut-off frequency. The correctness of the noise immunity analysis and the effectiveness of the improved OPD algorithm are verified by the simulations and experimental results in MATLAB and RT-LAB.

Supplemental material, sj-pdf-1-ajr-10.1177_1945892420982411 for Increased Expression of TXNIP Facilitates Oxidative Stress in Nasal Epithelial Cells of Patients With Chronic Rhinosinusitis With Nasal Polyps by Hai Lin MD, PhD, Guangyi Ba MD, Ru Tang MD, Mingxian Li MD, Zhipeng Li MD, PhD, Dawei Li MD, PhD, Haibo Ye MD, PhD, Weitian Zhang MD, PhD in American Journal of Rhinology & Allergy

Background The pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) has not been fully elucidated. This study sought to explore the role and mechanism of transient receptor potential canonical channel 6 (TRPC6) in the pathogenesis of CRSwNP. Methods Immunohistochemistry (IHC) was employed to evaluate TRPC6 immunolabeling. Real-time polymerase chain reaction (PCR) was conducted to assay TRPC6, stromal interaction molecule 1 (STIM1), and calcium release-activated calcium channel protein 1 (Orai1) messenger RNA (mRNA) levels in 70 patients with CRSwNP, including eosinophilic CRSwNP (ECRSwNP) or non-eosinophilic CRSwNP (nECRSwNP), and 28 control subjects. The concentrations of inflammatory mediators, including interleukin (IL)-1β, IL-5, and IL-25, were assayed by enzyme-linked immunosorbent assay (ELISA). In experiments on human nasal epithelial cell (HNEC) culture and stimulation, the mean fluorescence intensity (MFI) of intracellular Ca2+ was assayed by flow cytometry. Western blotting, real-time PCR, and ELISA were also conducted to assess the effects and mechanisms of TRPC6 activator 1-oleoyl-2-acetyl-glycerol (OAG) and TRPC6 inhibitor 1-[2-(4-methoxyphenyl)-2-[3-(4-methoxyphenyl) propoxy]ethyl-1H-imidazole (SKF-96365) on HNECs. Results Upregulation of TRPC6, STIM1, and Orai1 levels was found in CRSwNP patients, particularly in those with ECRSwNP. TRPC6-positive cells correlated positively with the numbers of eosinophils and neutrophils, respectively. Moreover, TRPC6 mRNA was positively correlated with STIM1 and Orai1 mRNA levels. The concentrations of inflammatory mediators, including IL-1β, IL-5, and IL-25, were elevated in CRSwNP, especially in ECRSwNP. In cultured HNECs, TRPC6, STIM1, Orai1, Ca2+ MFI levels, and inflammatory mediators were upregulated by lipopolysaccharide (LPS) and OAG but were inhibited by SKF-96365. Conclusion TRPC6 plays a pro-inflammatory role in the pathogenesis of CRSwNP via regulating Ca2+ flow.

Allergic rhinitis (AR) is a complex IgE-mediated nasal allergic and inflammatory disease. Nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) is essential in the process of allergic and inflammatory responses. MCC950 is a selective NLRP3 inhibitor. However, its role and mechanism in AR remains undetermined. The present study aimed to explore the effect and mechanism of MCC950 on an ovalbumin (OVA) induced mouse model of AR. The AR BALB/c mice were constructed using OVA and administrated intranasally with MCC950. Concentrations of OVA-specific IgE, histamines and leukotrienes C4 (LTC4) in serum, and OVA-specific IgE, ECP, IFN-γ, IL-4, IL-5, IL-13, IL-1β and IL-18 in nasal lavage fluid (NLF) were assayed by enzyme-linked immunosorbent assay (ELISA). Inflammatory cells were counted in NLF. HE and PAS staing were used for evaluating eosinophils and goblet cells. Immunohistochemistry (IHC) staining were employed to evaluate immunolabeling of NLRP3, Caspase-1, ASC, IL-1β and IL-18 in nasal mucosas of mice. Real-time PCR was conducted to assay NLRP3, Caspase-1, ASC, IL-1β and IL-18 mRNA levels. In vitro studies, western blotting, real-time PCR and ELISA were performed to evaluate the effects and mechanisms of OVA and NLRP3 inhibitor MCC950 on spleen mononuclear cells. We found significant downregulation of sneezing, nasal rubbing, inflammatory cytokines, inflammatory cells and NLRP3, Caspase-1, ASC, IL-1β and IL-18 expression in MCC950 treated mice compared with untreated AR mice. In spleen mononuclear cells culture and stimulation experiment, NLRP3, Caspase-1, ASC, IL-1β and IL-18 levels were upregulated by OVA but inhibited by MCC950. In conclusion, MCC950 could effectively exert its ameliorative effect in murine AR by inhibiting NLRP3 and leads to reduction of Caspase-1, ASC, IL-1β and IL-18, resulting in the attenuation of the allergic and inflammatory responses.

4-Nitrobenzaldehyde is the synthetic raw material and an important photodegradation product of chloramphenicol. With a structural “alert” of human genotoxic potential and reported mutagenicity, this compound should be controlled in drug substances as a potential genotoxic impurity. However, current analysis methods require complex pre-treatment processes and/or lack sufficient specificity and sensitivity. Nitrophenylhydrazine is a common carbonyl derivatization reagent used to determine the residual aromatic aldehydes in drug samples. In the present study, we report an unexpected advantage of 3-nitrophenylhydrazine hydrochloride as a derivatization reagent in the derivatization high-performance liquid chromatography-ultraviolet detection method to determine 4-nitrobenzaldehyde in chloramphenicol samples. Compared with other nitro-substituted phenylhydrazines, 3-nitrophenylhydrazine hydrochloride can minimize drug matrix and derivatization reagent interferences, since the maximum absorption wavelength of its derivative is significantly red-shifted to 397 nm. The derivatization conditions have been optimized in terms of reaction efficiency, including reaction temperature, time, and diluting solvent, through a design of experiments. As a result, after reaction with 500 μg mL −1 of 3-nitrophenylhydrazine hydrochloride in acetonitrile-water (70:30, v/v) at 60 °C for 30 min, the developed HPLC method could be used to determine 4-nitrobenzaldehyde with a limit of detection of 0.009 μg mL −1 . The method was then validated and applied for the determination of residual 4-nitrobenzaldehyde in chloramphenicol and its eye-drop samples.