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Pollen development is critical to plant reproduction, but the underlying regulatory molecular mechanisms have not been fully elucidated. The Arabidopsis (Arabidopsis thaliana) EFR3 OF PLANT 3 (EFOP3) and EFR3 OF PLANT 4 (EFOP4) genes encode members of the Armadillo (ARM) repeat superfamily that play key roles in pollen development. Herein, we demonstrate that EFOP3 and EFOP4 are co-expressed in pollen at anther stages 10-12, but loss-of-function of both EFOP3 and EFOP4 leads to male gametophyte sterility, irregular intine, and shriveled pollen grains at anther stage 12. We further established that full-length EFOP3 and EFOP4 specifically localize to the plasma membrane, and the integrity of these proteins is essential for pollen development. We observed uneven intine, less organized cellulose and reduced pectin content in mutant pollen compared with the wild-type. These, together with the misexpression of several genes related to cell wall metabolism in efop3-/- efop4+/- mutants, suggest that EFOP3 and EFOP4 may indirectly regulate the expression of these genes to affect intine formation, thus controlling Arabidopsis pollen fertility in a functionally redundant manner. Moreover, transcriptome analysis showed that the absence of EFOP3 and EFOP4 function affects multiple pollen development pathways. These results enhance our understanding of EFOPs proteins and their role in pollen development.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Polen , Fertilidad , Reproducción/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
Inflammatory pathways represented by TLR4/NF-κB (Toll-like receptor 4/Nuclear factor-κB) axis signaling are activated in the pathogenesis of endotoxin-induced myocardial dysfunction (EIMD). However, the underlying mechanism by which NF-κB coordinates with other transcriptional coactivators/corepressors to regulate the expression of proinflammatory cytokine genes remains unclear. We established an EIMD-mouse model by intraperitoneal injection of lipopolysaccharides (LPS), and we discovered that NCOA1 (nuclear receptor coactivator 1) assembled with CBP (CREB binding protein) and NF-κB subunits to form a transcriptional complex that specifically bound to promoters of proinflammatory cytokine genes to activate their expression. LPS treatment also inhibited DNMT1 (DNA methyltransferase 1) expression, thereby decreasing DNA methylation of a CpG island located on the promoter of NCOA1 and causing NCOA1 overexpression. Screening small molecules that abolished NCOA1-CBP interaction in a yeast system identified a compound PSSM2126 that effectively blocked the NCOA1-CBP interaction in vitro and in vivo. Administration of PSSM2126 to EIMD mice significantly alleviated the inflammation response and improved cardiac function. Collectively, our results reveal that an NCOA1-dependent transactivation mechanism can regulate proinflammatory cytokine expression, thereby improving our understanding of the activation of NF-κB targets. The promising inhibition of the NCOA1-CBP interaction by PSSM2126 may provide a new therapeutic option for EIMD.
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Proteína de Unión a CREB , Corazón , Inflamación , FN-kappa B , Coactivador 1 de Receptor Nuclear , Animales , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Citocinas/metabolismo , Endotoxinas , Corazón/fisiopatología , Inflamación/inducido químicamente , Inflamación/genética , Lipopolisacáridos/farmacología , Ratones , FN-kappa B/genética , FN-kappa B/metabolismo , Coactivador 1 de Receptor Nuclear/genética , Coactivador 1 de Receptor Nuclear/metabolismoRESUMEN
BACKGROUND: The relationship of fibrin(ogen) degradation products (FDPs) and potassium with the functional outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) is still uncertain. This study aims to evaluate the predictive value of a novel combination biomarker, the FDP-to-potassium ratio (FPR), for poor functional outcomes in patients with aSAH. METHODS: A total of 425 consecutive patients with aSAH at a single center were retrospectively enrolled in our study. An unfavorable outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 3 months after discharge. Univariate analysis and multivariable logistic regression were performed for baseline information and laboratory parameters recorded at admission. In addition, the receiver operating characteristic curve was plotted, and propensity score matching was performed based on the FPR. RESULTS: On the basis of mRS grade, 301 patients were classified as having favorable outcomes, and 124 patients were assessed as having unfavorable outcomes. FPR levels were significantly correlated with mRS grade (r[Spearman] = 0.410; P < 0.001). Multivariate logistic regression analysis showed that age (odds ratio [OR] 1.043, 95% confidence interval [CI] 1.016-1.071; P = 0.002), white blood cell count (OR 1.150, 95% CI 1.044-1.267; P = 0.005), potassium (OR 0.526, 95% CI 0.291-0.949; P = 0.033), World Federation of Neurosurgical Societies grade (OR 1.276, 95% CI 1.055-1.544; P = 0.012), and FPR (OR 1.219, 95% CI 1.102-1.349; P < 0.001) at admission were independently associated with poor functional outcomes. The DeLong test showed that the area under the receiver operating characteristic curve of FPR was higher than that of age, white blood cell count, potassium, World Federation of Neurosurgical Societies grade, or FDP alone, indicating that FPR had better predictive potential than these other variables. After 1:1 propensity score matching (FPR ≥ 1.45 vs. FPR < 1.45), the rate of poor prognosis was still significantly increased in the high-FPR group (48/121 [39.7%] vs. 16/121 [13.2%], P < 0.001). CONCLUSIONS: Fibrin(ogen) degradation product-to-potassium ratio is an independent predictor of poor outcomes for patients with aSAH and may be a promising tool for clinicians to evaluate patients' functional prognosis.
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OBJECTIVE: The aim of this study was to determine whether cognitive function is associated with future falls in older patients with diabetes mellitus (DM) compared with those without DM. Cognitive function was divided into several domains to further analyze. METHODS: A total of 678 individuals met the inclusion criteria and comprised the final study population. The mean age was 74.35 ± 5.35 years, and 58.9% of the participants were female (n = 400). At the baseline, cognitive function was measured by the Mini Mental State Examination (MMSE), and DM diagnoses were determined by medical records. The self-reported any falls data were obtained via face-to-face questioning at the 1-year follow-up. RESULTS: At baseline, 15.6% of participants (n = 106) were diagnosed with DM. According to whether they had any falls during 1-year follow-up, there was a significant difference between the two group in fasting plasma glucose (p = 0.012) and DM (p = 0.036) at baseline. Among the older adults with DM, those who had experienced any falls had poorer cognitive function (p = 0.014). After adjusting for various covariates, we found that MMSE (95% CI 0.790-0.991, p = 0.034), orientation to place (95% CI 0.307-0.911, p = 0.022) and registration (95% CI 0.162-0.768, p = 0.009) were significantly associated with falls in the follow-up. CONCLUSION: Our study found that in patients with DM, cognitive function is related to future falls. Not only overall cognitive function, but also orientation to place and registration were all associated with future falls in older adults with DM. When completing the fall risk assessment of elderly patients with DM, clinicians should give more attention to the testing of cognitive function.
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Diabetes Mellitus , Vida Independiente , Anciano , Femenino , Humanos , Masculino , Accidentes por Caídas , Cognición , Diabetes Mellitus/epidemiología , Pueblos del Este de AsiaRESUMEN
The exocyst is a key factor in vesicle transport and is involved in cell secretion, cell growth, cell division and other cytological processes in eukaryotes. EXO70 is the key exocyst subunit. We obtained a gene, SHORT-ROOT 1 (SR1), through map-based cloning and genetic complementation. SR1 is a conserved protein with an EXO70 domain in plants. SR1 mutation affected the whole root-development process: producing shorter radicles, adventitious roots and lateral roots, and demonstrating abnormal xylem development, resulting in dwarfing and reduced water potential and moisture content. SR1 was largely expressed in the roots, but only in developing root meristems and tracheary elements. The shortness of the sr1 mutant roots was caused by the presence of fewer meristem cells. The in situ histone H4 expression patterns confirmed that cell proliferation during root development was impaired. Tracheary element dysplasia was caused by marked decreases in the inner diameters of and distances between the perforations of adjacent tracheary elements. The membrane transport of sr1 mutants was blocked, affecting cell division in the root apical region and the development of root tracheary elements. The study of SR1 will deepen our understanding of the function of EXO70 genes in Oryza sativa (rice) and guide future studies on the molecular mechanisms involved in plant root development.
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Oryza/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Oryza/genética , Proteínas de Plantas/genética , Raíces de Plantas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismoRESUMEN
Compared with ex situ measurement, the in situ measurement is more suitable for inspecting complex electrochemical reactions and improving the intelligent energy storage management. However, most of the in situ investigation instruments are bulky and expensive. Here we demonstrate a miniaturized, portable, and low-cost fiber-optic sensing system for in situ monitoring the capacitance and temperature. It can help evaluate the self-discharge rate in supercapacitors (SCs). The fiber-optic sensing system with two probes are implanted inside the SCs to monitor the capacitance and temperature, respectively. The dual fiber-optic probes can work independently and avoid cross-interference through structure design. The fiber-optic localized surface plasmon resonance (LSPR) probe near the electrode surface can detect the capacitance in real-time by monitoring ion aggregation on the opposite electrode. The fiber-optic surface plasmon resonance (SPR) probe encapsulated in the thermosensitive liquid can independently detect the temperature change. The measurement uncertainties of the two sensing probes are 5.6 mF and 0.08 â, respectively. The proposed tiny and flexible fiber-optic sensing system provides a promising method for in situ monitoring the critical parameters. It is also a powerful tool for investigating electrochemical reactions in various energy storage devices.
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Due to the highly acidic and high-salinity nature of the high-level radioactive waste liquid (HLLW), selective extraction of TcO4- from HLLW remains to be a challenging task. Traditional anion exchangers show low selectivity and unsatisfactory extraction performance due to the lack of functional groups that can interact strongly with TcO4-. In this work, a tailor-made binding site was constructed by decorating two acetamide functional groups on imidazolium cation to fabricate a new Tc separation material, which exhibits high selectivity. Unlike most reported Tc separation materials, which can only perform well under low acidic, neutral, or alkaline conditions, this material still has good extraction performance in highly acidic solutions. In the simulated high-level waste liquid of 3 M nitric acid, the extraction efficiency of 0.5 mol/L organic phase for Tc can reach 96.5% through the first-stage extraction. Our theoretical simulations suggest that ReO4-/TcO4- anions were adsorbed on the top of the imidazolium ring during the extraction process, with p-π and p-p interactions acting as the driving forces.
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Sepsis-induced myocardial dysfunction (SIMD), a deadly symptom in sepsis patients, is mainly caused by cardiovascular inflammation. However, it remains unclear how systemic inflammation triggers and aggravates cardiovascular inflammation in the pathogenesis of SIMD. This study found that proinflammatory cytokines and H2 O2 concentrations were significantly induced in SIMD-mice. In particular, a microarray analysis of CD63+ exosomes isolated from sham- and SIMD-monocytes revealed a significant induction of thioredoxin-interacting protein (TXNIP) and NLR family pyrin domain-containing 3 (NLRP3). We proved that oxidative stress caused the disassociation of the TXNIP-TRX2 (thioredoxin 2) complex and the assembly of the TXNIP-NLRP3 complex. In addition, this finding showed that the latter complex could be embedded into CD63+ exosomes and traffic from monocytes to the resident heart macrophages, where it activated caspase-1 and cleaved inactive interleukin 1ß (IL-1ß) and IL-18. Furthermore, using an amplified luminescent proximity homogeneous assay (Alpha) with GST-TXNIP and His-NLRP3, we obtained a small molecule named PSSM1443 that could disrupt the TXNIP-NLRP3 interaction in vitro, impairing NLRP3 downstream events. Of note, after administering PSSM1443 to the SIMD-mice, we found the small molecule could significantly suppress the activation of caspase-1 and the cleavage of pro-IL-1ß and pro-IL-18, reducing inflammation in the SIMD-mice. Collectively, our results reveal that monocyte-derived exosomes harbor the overexpressed TXNIP-NLRP3 complex, which traffics from circulating monocytes to local macrophages and promotes the cleavage of inactive IL-1ß and IL-18 in the macrophages, aggravating cardiovascular inflammation. PSSM1443 functions as an inhibitor of the TXNIP-NLRP3 complex and its administration can decrease inflammation in SIMD-mice.
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Antiinflamatorios/farmacología , Proteínas Portadoras/metabolismo , Exosomas/efectos de los fármacos , Cardiopatías/prevención & control , Inflamasomas/metabolismo , Mediadores de Inflamación/metabolismo , Inflamación/prevención & control , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Sepsis/tratamiento farmacológico , Tiorredoxinas/metabolismo , Animales , Proteínas Portadoras/genética , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Exosomas/genética , Exosomas/inmunología , Exosomas/metabolismo , Cardiopatías/etiología , Cardiopatías/inmunología , Cardiopatías/metabolismo , Inflamasomas/genética , Inflamación/etiología , Inflamación/inmunología , Inflamación/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Activación de Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Monocitos/inmunología , Monocitos/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Estrés Oxidativo , Células RAW 264.7 , Sepsis/complicaciones , Sepsis/inmunología , Sepsis/metabolismo , Tetraspanina 30/metabolismo , Tiorredoxinas/genéticaRESUMEN
Lung cancer is the most common cause of cancer-related death in the world. Long non-coding RNAs (lncRNAs) are longer than 200 nucleotide transcripts, and are not translated into protein. The lncRNA linc00662 is overexpressed in lung cancer; however, its role in lung cancer is still unknown. In our study, by analyzing the TCGA data, we found that linc00662 was overexpressed in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). We knocked-down the expression of linc00662 using siRNA, and found that silencing linc00662 significantly inhibited the proliferation and colony formation of the lung cancer cell lines A549 and H460. We also found that knockdown of linc00662 increased the expression of the microRNA miR-145-5p and decreased the expression of the platelet-activating factor acetylhydrolase IB subunit beta (PAFAH1B2) gene. We further show that linc00662 binds with miR-145-5p, and that miR-145-5p binds to the 3'UTR of PAFAH1B2. miR-145-5p negatively regulates PAFAH1B2 both at the mRNA and the protein level. Loss of miR-145-5p abolished the inhibitory effects of silencing linc00662 on the proliferation and colony formation of A549 and H460 cells. These findings indicate that linc00662 functions as an oncogene by acting as a competing endogenous RNA (ceRNA) and sponges and regulates miR-145-5p in lung cancer, and thus may provide a potential target for treating lung cancer.
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1-Alquil-2-acetilglicerofosfocolina Esterasa/metabolismo , Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , MicroARNs/genética , Proteínas Asociadas a Microtúbulos/metabolismo , ARN Largo no Codificante/genética , 1-Alquil-2-acetilglicerofosfocolina Esterasa/genética , Anciano , Apoptosis , Biomarcadores de Tumor/genética , Proliferación Celular , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/genética , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Células Tumorales CultivadasRESUMEN
Nucleotide-binding site-leucine-rich repeat (NB-LRR) resistance proteins are critical for plant resistance to pathogens; however, their mechanism of activation and signal transduction is still not well understood. We identified a mutation in an as yet uncharacterized rice coiled-coil (CC)-NB-LRR, Oryza sativa RPM1-like resistance gene 1 (OsRLR1), which leads to hypersensitive response (HR)-like lesions on the leaf blade and broad-range resistance to the fungal pathogen Pyricularia oryzae (syn. Magnaporthe oryzae) and the bacterial pathogen Xanthomonas oryzae pv. oryzae, together with strong growth reduction. Consistently, OsRLR1-overexpression lines showed enhanced resistance to both pathogens. Moreover, we found that OsRLR1 mediates the defence response through direct interaction in the nucleus with the transcription factor OsWRKY19. Down-regulation of OsWRKY19 in the rlr1 mutant compromised the HR-like phenotype and resistance response, and largely restored plant growth. OsWRKY19 binds to the promoter of OsPR10 to activate the defence response. Taken together, our data highlight the role of a new residue involved in the NB-LRR activation mechanism, allowing identification of a new NB-LRR downstream signalling pathway.
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Oryza , Xanthomonas , Ascomicetos , Sitios de Unión , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Nucleótidos , Oryza/genética , Oryza/metabolismo , Enfermedades de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
BACKGROUND: The shortage of benzathine penicillin G (BPG) worldwide presents a major challenge in the treatment of syphilis. Its availability for syphilis treatment has not been adequately evaluated in China. METHODS: Two surveys were conducted among hospitals providing sexually transmitted infection clinical services in Shandong Province in 2012 and 2018. Data on the basic information and BPG availability of the surveyed hospitals and related factors were collected and analyzed using SPSS 17.0. RESULTS: A total of 433 and 515 hospitals were surveyed in 2012 and 2018, respectively. A significant difference in BPG availability was observed among different levels and types of hospitals both in 2012 (X2 = 9.747, p = 0.008; X2 = 37.167, p = 0.000) and 2018 (X2 = 11.775, p = 0.003; X2 = 28.331, p = 0.000). The BPG availability among surveyed hospitals increased from 45.0% in 2012 to 56.4% in 2018 (X2 = 11.131, p = 0.001). The BPG availability was higher in 2018 than in 2012 among county-level hospitals (52.0% vs. 40.8%, X2 = 7.783, p = 0.005), general western medicine hospitals (62.1% vs. 50.0%, X2 = 6.742, p = 0.009), maternal and child health hospitals (57.1% vs. 26.9%, X2 = 13.906, p = 0.000), and public hospitals (56.8% vs. 45.0%, X2 = 11.361, p = 0.001). However, the county-level availability of BPG (at least one hospital has BPG in a county-level unit) has not improved between 2012 and 2018 (65.93% vs. 70.34%; X2 = 0.563, p = 0.453). The absences of clinical needs, restriction of clinical antibacterial drugs, and lack of qualifications for providing syphilis treatment were the major reasons for the low BPG availability of hospitals. CONCLUSIONS: BPG availability for syphilis treatment in Shandong Province remains low and presents disparities among different levels and types of hospitals, although it has been improved in recent years. The low availability of BPG for syphilis treatment in China is related to its clinical use by doctors rather than the market supply. Health care reforms should further improve the availability and accessibility of health services.
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Antibacterianos/provisión & distribución , Hospitales , Penicilina G Benzatina/provisión & distribución , Sífilis/tratamiento farmacológico , Antibacterianos/uso terapéutico , China , Humanos , Penicilina G Benzatina/uso terapéutico , Encuestas y CuestionariosRESUMEN
Calcium-dependent protein kinases are involved in various biological processes, including hormone response, growth and development, abiotic stress response, disease resistance, and nitrogen metabolism. We identified a novel mutant of a calcium-dependent protein-kinase-encoding gene, esl4, by performing map cloning. The esl4 mutant was nitrogen deficient, and expression and enzyme activities of genes related to nitrogen metabolism were down-regulated. ESL4 was mainly expressed in the vascular bundles of roots, stems, leaves, and sheaths. The ESL4 protein was localized in the cell membranes. Enzyme activity and physiological index analyzes and analysis of the expression of nitrogen metabolism and senescence-related genes indicated that ESL4 was involved in nitrogen metabolism. ESL4 overexpression in transgenic homozygous T2 plants increased nitrogen-use efficiency, improving yields when little nitrogen was available. The seed-set rates, yields per plant, numbers of grains per plant, grain nitrogen content ratios, and total nitrogen content per plant were significantly or very significantly higher for two ESL4 overexpression lines than for the control plants. These results suggest that ESL4 may function upstream of nitrogen-metabolism genes. The results will allow ESL4 to be used to breed novel cultivars for growing in low-nitrogen conditions.
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Genes de Plantas , Mutación/genética , Nitrógeno/deficiencia , Nitrógeno/metabolismo , Oryza/genética , Proteínas de Plantas/genética , Proteínas Quinasas/genética , Membrana Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Fenotipo , Floema/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Recombinantes/metabolismo , Fracciones Subcelulares/metabolismoRESUMEN
At present, most of the existing practical ultraviolet (UV) solar-blind detectors are based on Te-Cs photocathode image intensifiers. However, limited by their photoemission characteristics, it is difficult for the Te-Cs-based photocathodes to achieve both high quantum efficiency in the application band and high cutoff ratio in the non-applied band simultaneously. In this paper, a high-quantum-efficiency UV solar-blind detector based on AlGaN photocathodes with a sharp spectral sensitivity threshold at 300 nm is reported. The proposed AlGaN photocathode has extremely high quantum efficiency (i.e., 20%) in the 210-275 nm band, while the efficiency curve steeply reduces to 2% at 300 nm, showing obviously superior performance than the existing Te-Cs photocathodes.
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In order to understand the photoemission mechanism of the reflection-mode InGaAs photocathode with a thin emission layer, the formula describing reflection-mode quantum efficiency is revised by solving the one-dimensional continuity equation, in which the electrons generated in the GaAs buffer layer are considered. Compared with the conventional formula, the revised formula is proved to be more suitable for the reflection-mode InGaAs photocathode with a thin emission layer. In experiment, the InGaAs sample goes through two-step surface preparation including a wet chemical cleaning process and a heat treatment process. Then the sample is activated by Cs/O and the experimental quantum efficiency curves are measured simultaneously every other hour. The measured results show that the shapes of the quantum efficiency curves degrade with time because of the contamination of residual gases in the vacuum system. All the quantum efficiency curves are well fitted by the revised formula.
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Photocathode surface treatment aims to obtain high sensitivity, where the key point is to acquire an atomically clean surface. Various surface cleaning methods for removing contamination from InGaAs photocathode surfaces were investigated. The atomic compositions of InGaAs photocathode structures and surfaces were measured by x-ray photoelectron spectroscopy and Ar ion sputtering. After surface cleaning, the InGaAs surface is arsenoxide-free, however, a small amount of Ga2O3 and In2O3 still can be found. The 1:1 mixed solution of hydrochloric acid to deionized water followed by thermal annealing at 525°C has been demonstrated to be the best choice in dealing with the surface oxides. After the Cs/O activation, a surface model was proposed where the oxides on the surface will lead to a positive electron affinity, adversely affecting low-energy electrons escaping to the vacuum, which is reflected by the photocurrent curves and the spectral response curves.
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The effect of Cs adsorption on the photoemission performance of a reflection-mode GaAlAs photocathode in an ultrahigh vacuum chamber has been investigated. The experiments for Cs/O activation, multiple recaesiation, and degradation are performed on a GaAlAs photocathode. Meanwhile, the Cs/O activated and recaesiated photocurrent curves, degraded photocurrent curves, and spectral response curves are measured and analyzed. Besides, the performance parameters of the photocathodes are obtained by using the formula to fit with the experimental quantum efficiency curves. The results show that the Cs atoms not only make the atomically clean surface form the negative electron affinity, but also make the degraded photocathode recover to a good level. The quantum efficiency and the lifetime of GaAlAs photocathode become lower with increasing the recaesiation times.
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To research the photoemission performance of a transmission-mode Al(1-x)Ga(x)N photocathode, Al0.24Ga0.76N and GaN photocathodes with the same structure were activated, their spectral responses were measured using a multi-information measurement system at room temperature, and the photocathode parameters were obtained by fitting quantum efficiency curves. The results showed that both the reflective-mode and transmission-mode spectral responses of the AlGaN photocathode were lower than those of the GaN photocathode. Compared with the GaN photocathode, the short-wavelength spectral response of the Al0.24Ga0.76N photocathode was less seriously affected by lattice defects between the buffer and emission layers. The Al atom at the AlGaN photocathode surface could affect the optimal Cs adsorption position, which mainly affects the surface electron escape probability of the photocathode.
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Venomous toxins hold immense value as tools in elucidating the intricate structure and underlying mechanisms of ion channels. In this article, we identified of two novel toxins, Hainantoxin-XXI (HNTX-XXI) and Hainantoxin-XXII (HNTX-XXII), derived from the venom of the Chinese spider Ornithoctonus hainana. HNTX-XXI, boasting a molecular weight of 6869.095 Da, comprises 64 amino acid residues and contains 8 cysteines. Meanwhile, HNTX-XXII, with a molecular weight of 8623.732 Da, comprises 77 amino acid residues and contains 12 cysteines. Remarkably, we discovered that both HNTX-XXI and HNTX-XXII possess the ability to activate TRPV1. They activated TRPV1 with EC50 values of 3.6 ± 0.19 µM and 862 ± 56 nM, respectively. Furthermore, the current generated by the activation of TRPV1 by these toxins can be rapidly blocked by ruthenium red. Intriguingly, our analysis revealed that the interaction between HNTX-XXI and TRPV1 is mediated by three key amino acid residues: L465, V469, and D471. Similarly, the interaction between HNTX-XXII and TRPV1 is facilitated by four key amino acid residues: A657, F659, E600, and R601. These findings provide profound insights into the molecular basis of toxin-TRPV1 interactions and pave the way for future research exploring the therapeutic potential of these toxic peptides.
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Venenos de Araña , Canales Catiónicos TRPV , Animales , Humanos , Secuencia de Aminoácidos , Células HEK293 , Unión Proteica , Venenos de Araña/química , Venenos de Araña/farmacología , Arañas/metabolismo , Canales Catiónicos TRPV/metabolismo , Canales Catiónicos TRPV/química , Canales Catiónicos TRPV/genéticaRESUMEN
Industrial activities pose a significant ecological risk to water resources as they pollute surrounding waters with vanadium (V). Although the contribution of plants and substrates to V removal in constructed wetlands (CWs) has been reported, the role of arbuscular mycorrhizal fungi (AMF) is unclear. The aim of the present study was to investigate the role of AMF in V removal in CWs and to elucidate the underlying mechanisms. Reed plants (Phragmites australis) were inoculated with an AMF strain (Rhizophagus irregularis) in CW columns, creating AMF-inoculated (+AMF) and non-inoculated (-AMF) treatments. Three levels of influent V concentrations (low: 0.50 mg L-1, medium: 1.14 mg L-1 and high: 1.52 mg L-1) were examined. The + AMF treatment showed higher V removal (60%-98%) than the control (40%-82%) in all three conditions, although the difference was not significant in some cases. The mean mycorrhizal effects were 75%, 19%, and 28% for low, moderate, and high influent V concentrations, respectively. The +AMF treatment showed a higher GRSP-bonded V concentration (5.5 mg g-1) than the -AMF treatment (4.0 mg g-1). Furthermore, +AMF treatment showed larger plants with higher V concentrations in their tissues, accompanied by increased biological concentration factors and biological accumulation factors. Given the remarkable positive effect of AMF on V removal, our study suggests that treating AMF in CWs is a worthwhile approach.
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Micorrizas , Humedales , Vanadio , Ríos , Hongos , Plantas , Agua , Raíces de Plantas/microbiologíaRESUMEN
Graph Neural Networks (GNNs) have demonstrated great potential in achieving outstanding performance in various graph-related tasks, e.g., graph classification and link prediction. However, most of them suffer from the following issue: shallow networks capture very limited knowledge. Prior works design deep GNNs with more layers to solve the issue, which however introduces a new challenge, i.e., the infamous over-smoothness. Graph representation over emphasizes node features but only considers the static graph structure with a uniform weight are the key reasons for the over-smoothness issue. To alleviate the issue, this paper proposes a Dynamic Weighting Strategy (DWS) for addressing over-smoothness. We first employ Fuzzy C-Means (FCM) to cluster all nodes into several groups and get each node's fuzzy assignment, based on which a novel metric function is devised for dynamically adjusting the aggregation weights. This dynamic weighting strategy not only enables the intra-cluster interactions, but also inter-cluster aggregations, which well addresses undifferentiated aggregation caused by uniform weights. Based on DWS, we further design a Structure Augmentation (SA) step for addressing the issue of underutilizing the graph structure, where some potentially meaningful connections (i.e., edges) are added to the original graph structure via a parallelable KNN algorithm. In general, the optimized Dynamic Weighting Strategy with Structure Augmentation (DWSSA) alleviates over-smoothness by reducing noisy aggregations and utilizing topological knowledge. Extensive experiments on eleven homophilous or heterophilous graph benchmarks demonstrate the effectiveness of our proposed method DWSSA in alleviating over-smoothness and enhancing deep GNNs performance.