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In this paper, a novel concurrent design of integrated PIN-diode based limiter and low noise amplifier (LNA) is presented for Ka-band MMICs fabricated using a combined PIN/0.15-μm-pHEMT technology. To improve the small-signal performance and the power-handling capability of the limiter-LNA, the improvement of the PIN-limiter circuit structure and the survivability of the LNA network are proposed. In addition, the total chip area is 2.5 mm × 1.2 mm with an equalizer integrated on chip behind the limiter-LNA to improve the bandwidth with a minimum impact on overall NF. The measurements show that the proposed limiter-LNA with only two-stage limiter structure tolerates up to 38 dBm continuous wave (CW) input power without failure, and the average gain and the noise figure for the limiter-LNA are 17 dB and 2.2 - 2.6 dB, respectively, on the 30 - 38 GHz frequency bandwidth.

As the dominant spoilage bacterium in meat, Pseudomonas poses a significant threat to meat quality and safety. The biofilm of Pseudomonas not only enhances stress resistance but also provides bio-protection, thereby making the decontamination of Pseudomonas more challenging. In recent years, many studies have been conducted on the mechanism of Pseudomonas biofilm formation, with particular emphasis on the regulatory effect of quorum sensing (QS) and cyclic di-guanosine monophosphate (c-di-GMP) on the mechanism of Pseudomonas biofilm formation. There may be a complex interaction between QS and c-di-GMP. In addition, compared with traditional biofilm inhibition strategies, the development of new inhibition strategies based on the QS system, c-di-GMP and their relationship, which can be more targeted, has more practical significance. Therefore, this article describes the synthesis process of the QS system and c-di-GMP signal molecules and reviews the mechanism of Pseudomonas biofilm formation from the perspectives of the QS system, c-di-GMP and their relationship. Besides, it summarizes the inhibition strategies targeting the QS system and c-di-GMP. This review aims to provide a theoretical foundation for effectively controlling Pseudomonas biofilm in the food industry.

Hydroclimate over the Tibetan Plateau (TP) notably influences the eco-environment of the Northern Hemisphere. Given its high elevation and complex topography, the climate in the TP shows a high sensitivity to anthropogenic warming and volcanic-induced cooling. The mechanism by which a future volcanic or similar radiative perturbation affects precipitation in the TP under an anthropogenic warming climate must be addressed not only to enable regional adaptation but deepen our understanding of how a climate system evolves under such a dual force. Here, based on the Community Earth System Model version 1.2 and ensemble simulations under pre-industrial and RCP8.5 scenarios, we showed that a Tambora-sized volcanic perturbation led to severe rainfall reduction over the south TP in the following summer (June–August). Evaporation response accounted for a minor and relatively constant share of precipitation reduction following the Clausius–Clapeyron scaling, whereas dynamic processes triggered an El Niño-like response in the eastern equatorial Pacific, which suppressed the Walker and Hadley circulation and contributed to drying anomalies. Global warming renders the post-Tambora hydroclimate responses with 30% higher severity as a result of the increased climatological moisture content and intensified El Niño response, which enhanced hydroclimate sensitivity and attenuated monsoon circulation. The results illustrate the amplification effect of global warming on the plateau's hydroclimate responses to external forcings, which may add another layer of uncertainty on climate adaptation in this already complex region.

In this paper, we propose a novel gallium nitride-based multi-two-dimensional-electron-gas (2DEG)-channel self-parallel Gunn diode (SPD) for the first time. In the SPD, a trench anode is etched through at least the bottommost 2DEG channels, which splits all 2DEG channels into two shorter channels with lengths of L1 and L2. Therefore, one SPD is just equal to several shorter diodes in parallel; as a result, we call it a self-parallel Gunn diode. In the symmetrical SPD, the component of fundamental frequency is nearly multiplied as compared with the regular Gunn diode. In the asymmetrical SPD (L2 = nL1, n is a positive integer), the harmonic components are greatly enhanced, specially the nth harmonic. Our work demonstrates that the GaN-based terahertz SPD not only offers an easy transfer between two different frequencies, but also realizes the simultaneous enhancement of oscillation power and frequency.

Objective To evaluate the clinical application value of transforaminal endoscope-guided module in the treatment of lumbar disc herniation by transforaminal endoscopic. Methods Sixty patients with L5 / S1 lumbar disc herniation were randomly divided into the module group and control group， with 30 cases in each group. In the module group， self-designed transforaminal endoscope-guided module was utilized to assist puncture， and conventional manual puncture was adopted to place the working channel in control group. The success rate of one-time puncture， positioning puncture time and intraoperative X-ray fluoroscopy times were compared between two groups， and the incidence of complications was observed. The Visual Analogue Scale （VAS） score and Oswestry Disability Index （ODI） score of the hip and lower limbs at postoperative 3 months were compared between two groups. Postoperative modified Mac Nab score was employed to evaluate clinical efficacy between two groups. Results All patients successfully completed the operation. Compared with the control group， the success rate of one-time puncture was higher， positioning puncture time was shorter and the times of intraoperative X-ray fluoroscopy was less in the module group （all P <0.05）. There was no statistical significance in the incidence of intraoperative complications between two groups （P >0.05）， and no severe postoperative complications were noted in two groups. In two groups， the VAS score and ODI score at postoperative 3 months were less compared with preoperative levels （both P <0.05）， and there was no statistical significance between two groups （both P >0.05），however， the difference of VAS between preoperative and postoperative values was statistically significant（P <0.05）. There was no statistical significance in the excellent rate of modified Mac Nab score between the module （83.3% （25/30））and control groups （80.0% （24/30）， P >0.05）. Conclusions Transforaminal endoscope-guided module is safe and convenient. This module can effectively shorten puncture time， enhance puncture efficiency and minimize iatrogenic injuries， which is worthy of clinical application.

Salicylic acid (SA) is widely used in food storage, preservatives, additives, healthcare, and the pharmaceutical industry. However, various poisoning symptoms are frequently reported upon ingestion of a large amount of SA. Therefore, discovering new tools for sensing SA with fast, simple, and portable performance is imperative. Herein, five rhodamine-based fluorescent sensors were constructed, and investigated their SA detection profiles. Probe 1 was excellent selective with a rapid response, highly sensitive (LOD = 2.5 μM), good interference resistance, and unaided eye recognition. The spray experiment and paper-based test strips indicating that probe 1 enables to the on-site and quantitatively detect SA on actual food surfaces by using a smartphone identifying the RGB values. The sensing performance was validated in soil samples, water, and various agricultural food samples. Overall, the constructed SA sensor can function as a promising, convenient, and affordable tool for point-of-care detection of SA in diversiform environmental samples.

In this study, we describe and illustrate a new species, Primula weiliei L.S.Yang, Z.K.Wu & G.W.Hu, from the Shennongjia Forestry District, Hubei Province in Central China. It is morphologically assigned to Primula sect. Aleuritia based on its dwarf and hairless habit, long petiole, fruits longer than calyx and covered by farina on the scape. This new species is similar to P. gemmifera and P. munroi subsp. yargongensis in the same section, but it can be distinguished by its smaller calyxes, homostylous flowers, corolla tube throat without annular appendage and only 1–2 flowers in each inflorescence. Based on the assessment conducted according to the IUCN Red List criteria, we propose that P. weiliei be classified as a Critically Endangered (CR) species.

Abstract Seven undescribed compounds, including three flavones (1–3), one phenylpropanoid (19), three monoaromatic hydrocarbons (27–29), were isolated from the twigs of Mosla chinensis Maxim together with twenty-eight known compounds. The structures were characterized by HRESIMS, 1D and 2D NMR, and ECD spectroscopic techniques. Compound 20 displayed the most significant activity against A/WSN/33/2009 (H1N1) virus (IC50 = 20.47 μM) compared to the positive control oseltamivir (IC50 = 6.85 µM). Further research on the anti-influenza mechanism showed that compound 20 could bind to H1N1 virus surface antigen HA1 and inhibit the early attachment stage of the virus. Furthermore, compounds 9, 22, 23, and 25 displayed moderate inhibitory effects on the NO expression in LPS inducing Raw 264.7 cells with IC50 values of 22.78, 20.47, 27.66, and 30.14 µM, respectively. Graphical Abstract

The high recurrence rate of cervical cancer is a leading cause of cancer deaths in women. 5-Fluorouracil (5-FU) is an antitumor drug used to treat many types of cancer, but its diminishing effectiveness and side effects limit its use. Norcantharidin (NCTD), a demethylated derivative of cantharidin, exhibits various biological activities. Here, we investigated whether NCTD could potentiate 5-FU to induce cervical cancer cell death. To assess the cell viability and synergistic effects of the drugs, cell counting kit-8 and colony formation assays were performed using HR-HPV-positive cervical cancer cell lines. Annexin V-FITC/PI staining and TUNEL assays were performed to confirm the induction of apoptosis. The synergistic effect of NCTD on the antitumor activity of 5-FU was analyzed using network pharmacology, molecular docking, and molecular dynamics simulations. Apoptosis-related proteins were examined using immunoblotting. The combination of NCTD and 5-FU was synergistic in cervical cancer cell lines. Network pharmacological analysis identified 10 common targets of NCTD and 5-FU for cervical cancer treatment. Molecular docking showed the strong binding affinity of both compounds with CA12, CASP9, and PTGS1. Molecular dynamics simulations showed that the complex system of both drugs with caspase-9 could be in a stable state. NCTD enhanced 5-FU-mediated cytotoxicity by activating apoptosis-related proteins. NCTD acts synergistically with 5-FU to inhibit cervical cancer cell proliferation. NCTD enhances 5-FU-induced apoptosis in cervical cancer cell lines via the caspase-dependent pathway.

The contribution of plant hormones and energy-rich compounds and their metabolites (ECMs) in alleviating aluminum (Al) toxicity by elevated pH remains to be clarified. For the first time, a targeted metabolome was applied to identify Al-pH-interaction-responsive hormones and ECMs in Citrus sinensis leaves. More Al-toxicity-responsive hormones and ECMs were identified at pH 4.0 [4 (10) upregulated and 7 (17) downregulated hormones (ECMs)] than those at pH 3.0 [1 (9) upregulated and 4 (14) downregulated hormones (ECMs)], suggesting that the elevated pH improved the adaptation of hormones and ECMs to Al toxicity in leaves. The roles of hormones and ECMs in reducing leaf Al toxicity mediated by elevated pH might include the following aspects: (a) improved leaf growth by upregulating the levels of jasmonoyl-L-isoleucine (JA-ILE), 6-benzyladenosine (BAPR), N6-isopentenyladenosine (IPR), cis-zeatin-O-glucoside riboside (cZROG), and auxins (AUXs), preventing Al toxicity-induced reduction of gibberellin (GA) biosynthesis, and avoiding jasmonic acid (JA)-mediated defense; (b) enhanced biosynthesis and accumulation of tryptophan (TRP), as well as the resulting increase in biosynthesis of auxin, melatonin and secondary metabolites (SMs); (c) improved ability to maintain the homeostasis of ATP and other phosphorus (P)-containing ECMs; and (d) enhanced internal detoxification of Al due to increased organic acid (OA) and SM accumulation and elevated ability to detoxify reactive oxygen species (ROS) due to enhanced SM accumulation. To conclude, the current results corroborate the hypotheses that elevated pH reduces Al toxicity by upregulating the ability to maintain the homeostasis of ATP and other P-containing ECMs in leaves under Al toxicity and (b) hormones participate in the elevated pH-mediated alleviation of Al toxicity by positively regulating growth, the ability to detoxify ROS, and the internal detoxification of Al in leaves under Al toxicity. Our findings provide novel insights into the roles of hormones and ECMs in mitigating Al toxicity mediated by the elevated pH.

Isoprenoid metabolism and its derivatives took part in photosynthesis, growth regulation, signal transduction, and plant defense to biotic and abiotic stresses. However, how aluminum (Al) stress affects the isoprenoid metabolism and whether isoprenoid metabolism plays a vital role in the Citrus plants in coping with Al stress remain unclear. In this study, we reported that Al–treatment–induced alternation in the volatilization rate of monoterpenes (α–pinene, β–pinene, limonene, α–terpinene, γ–terpinene and 3–carene) and isoprene were different between Citrus sinensis (Al-tolerant) and C. grandis (Al-sensitive) leaves. The Al-induced decrease of CO2 assimilation, maximum quantum yield of primary PSII photochemistry (Fv/Fm), the lower contents of glucose and starch, and the lowered activities of enzymes involved in the mevalonic acid (MVA) pathway and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway might account for the different volatilization rate of isoprenoids. Furthermore, the altered transcript levels of genes related to isoprenoid precursors and/or derivatives metabolism, such as geranyl diphosphate (GPP) synthase (GPPS) in GPP biosynthesis, geranylgeranyl diphosphate synthase (GGPPS), chlorophyll synthase (CHS) and GGPP reductase (GGPPR) in chlorophyll biosynthesis, limonene synthase (LS) and α-pinene synthase (APS) in limonene and α–pinene synthesis, respectively, might be responsible for the different contents of corresponding products in C. grandis and C. sinensis. Our data suggested that isoprenoid metabolism was involved in Al tolerance response in Citrus, and the alternation of some branches of isoprenoid metabolism could confer different Al-tolerance to Citrus species.

Abstract The bottom-up molecular science research paradigm has greatly propelled the advancement of materials science. However, some organic molecules can exhibit markedly different properties upon aggregation. Understanding the emergence of these properties and structure-property relationship has become a new research hotspot. In this work, by taking the unique closed-form rhodamines-based aggregation-induced emission (AIE) system as model compounds, we investigated their luminescent properties and the underlying mechanism deeply from a top-down viewpoint. Interestingly, the closed-form rhodamine-based AIE system did not display the expected emission behavior under high-viscosity or low-temperature conditions. Alternatively, we finally found that the molecular conformation change upon aggregation induced intramolecular charge transfer emission and played a significant role for the AIE phenomenon of these closed-form rhodamine derivatives. The application of these closed-form rhodamine-based AIE probe in food spoilage detection was also explored.

Limited data are available on copper (Cu)–pH interaction-responsive genes and/or metabolites in plant roots. Citrus sinensis seedlings were treated with 300 μM (Cu toxicity) or 0.5 μM (control) CuCl2 at pH 3.0 or 4.8 for 17 weeks. Thereafter, gene expression and metabolite profiles were obtained using RNA-Seq and widely targeted metabolome, respectively. Additionally, several related physiological parameters were measured in roots. The results indicated that elevating the pH decreased the toxic effects of Cu on the abundances of secondary metabolites and primary metabolites in roots. This difference was related to the following several factors: (a) elevating the pH increased the capacity of Cu-toxic roots to maintain Cu homeostasis by reducing Cu uptake and Cu translocation to young leaves; (b) elevating the pH alleviated Cu toxicity-triggered oxidative damage by decreasing reactive oxygen species (ROS) formation and free fatty acid abundances and increasing the ability to detoxify ROS and maintain cell redox homeostasis in roots; and (c) increasing the pH prevented root senescence and cell wall (CW) metabolism impairments caused by Cu toxicity by lowering Cu levels in roots and root CWs, thus improving root growth. There were some differences and similarities in Cu–pH interaction-responsive genes and metabolites between leaves and roots.

BackgroundWith increasing gaps between the rich and poor, potential risk factors for class conflict have attracted increasing attention from researchers. Although cognitive factors are known to be significant predictors of class-conflict behavior, limited attention has been paid to competence stereotypes of the upper class. When considering economic inequality, people pay more attention to competence stereotypes of the upper class, which may have adverse effects. This study aimed to investigate the relationship between competence stereotypes held by the lower class about the upper class and class conflict, and to test the mediating role of intergroup envy in this relationship and the moderating role of upward social mobility belief.MethodsData were collected from a convenience sample from a comprehensive university in China. Based on scores on subjective and objective class scales, 284 lower-class college students (103 males and 181 females) aged 18–24 were selected to participate (both their subjective and objective scores were lower than 3 points). Their endorsement of upper-class competence stereotypes, intergroup envy, upward social mobility beliefs, and class conflict were measured using a well-validated self-report questionnaire.ResultsThe main data were analyzed using correlation analysis, the SPSS macro PROCESS (Model 7), and simple slope analysis. The results show a significant positive correlation between competence stereotypes held by lower-class college students toward the higher class and class conflict, and this connection was mediated by intergroup envy. Moreover, the indirect effect of intergroup envy on this link was moderated by upward social mobility beliefs; this effect was stronger for college students with lower upward social mobility beliefs.ConclusionThis study broadens our understanding of how and when competence stereotypes among the lower class concerning the upper class are related to class conflict. Researchers and policymakers should pay special attention to competence stereotypes of the upper class, especially intergroup envy and class conflict among lower-class individuals with lower levels of upward social mobility beliefs.

Background Bell’s palsy is an idiopathic peripheral nerve palsy involving the facial nerve. Pregnancy, diabetes mellitus and hypertension are the risk factors for Bell’s palsy. However, the association between hypertensive disorders and Bell’s palsy during pregnancy or the puerperium remains unclear. This systematic review will comprehensively summarise the literature and evaluate the association between Bell’s palsy and hypertensive disorders during pregnancy or the puerperium.Methods and analysis Systematic searches of PubMed, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials will be undertaken using prespecified search strategies. Observational studies (cross-sectional studies, cohort studies, case reports and series case reports) written in English that investigate the association between hypertensive disorders of late pregnancy and Bell’s palsy during pregnancy or the puerperium will be included. Different authors will independently conduct the eligible study selection, perform data extraction and appraise the quality of included studies. Subgroup analysis will be carried out based on the age of pregnant women (≤35 years old, >35 years old), parity (primipara, multipara) and fetus number (singleton or multiple-gestation pregnancy).Ethics and dissemination This review will be based on published literature, and thus there is no requirement for ethics approval. The results of this study will aid in the knowledge of the relationship between Bell’s palsy during pregnancy or the puerperium and hypertensive disorders of late pregnancy. The results of this systematic review will be shared through publication in a peer-reviewed journal with good visibility for the field of obstetrics and presentations at academic conferences.PROSPERO registration number CRD42023422902.

Abstract Background The association between muscle defects and hypertension is well-established. However, the absence of pertinent and uncomplicated clinical indicators presents a challenge. Relative muscle strength (RMS) may offer a viable indicator. This study aimed to explore the association between RMS and hypertension. Methods A total of 12,720 individuals aged ≥ 45 years from the 2011 wave of the China Health and Retirement Longitudinal Study (CHARLS) were included. Grip strength was recorded and appendicular skeletal muscle mass (ASM) was estimated using a validated mathematical formula. The RMS was calculated as the ratio of grip strength to ASM. Hypertension was determined based on previous diagnosis, history of hypertension medication use, and current blood pressure. Logistic regression models were employed to investigate the relationship between RMS and hypertension. Results The prevalence of hypertension was 41.7% (5,307/12,720 patients). RMS was negatively correlated with hypertension with an OR (95% CI) of 0.68 (0.59–0.79) for males, 0.81 (0.73–0.90) for females, and 0.78 (0.72–0.85) for the entire population after adjusting for related covariates including age, education, marital history, smoking history, drinking history, diabetes, hyperlipidemia, and obesity. The trend test showed a linear association among males, females, or the entire population. Stratified analysis showed a consistent negative correlation between RMS and hypertension. Conclusions Higher RMS is an independent protective factor against hypertension and efforts to promote RMS may be beneficial for the prevention and management of hypertension.

Some citrus orchards in China often experience nitrogen (N) deficiency. For the first time, targeted metabolomics was used to examine N-deficient effects on hormones in sweet orange (Citrus sinensis (L.) Osbeck cv. Xuegan) leaves and roots. The purpose was to validate the hypothesis that hormones play a role in N deficiency tolerance by regulating root/shoot dry weight ratio (R/S), root system architecture (RSA), and leaf and root senescence. N deficiency-induced decreases in gibberellins and indole-3-acetic acid (IAA) levels and increases in cis(+)-12-oxophytodienoic acid (OPDA) levels, ethylene production, and salicylic acid (SA) biosynthesis might contribute to reduced growth and accelerated senescence in leaves. The increased ethylene formation in N-deficient leaves might be caused by increased 1-aminocyclopropanecarboxylic acid and OPDA and decreased abscisic acid (ABA). N deficiency increased R/S, altered RSA, and delayed root senescence by lowering cytokinins, jasmonic acid, OPDA, and ABA levels and ethylene and SA biosynthesis, increasing 5-deoxystrigol levels, and maintaining IAA and gibberellin homeostasis. The unchanged IAA concentration in N-deficient roots involved increased leaf-to-root IAA transport. The different responses of leaf and root hormones to N deficiency might be involved in the regulation of R/S, RSA, and leaf and root senescence, thus improving N use efficiency, N remobilization efficiency, and the ability to acquire N, and hence conferring N deficiency tolerance.