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Most of the current holographic waveguide display systems are designed based on the center beam. When the incident beam consists of rays with different angles, the field of view and optical efficiency would greatly reduce. The heavy angular dependence of the volume holographic grating (VHG) and the back-coupling loss are two main reasons. This paper proposes a design method of the waveguide display system with multiplexed VHG, which is based on a genetic algorithm to optimize and calculate the parameters both of the VHG and the waveguide. The simulation results show that the diagonal field of view of the holographic waveguide system is increased to 28°, and its optical efficiency is improved by 30%. The design method of the waveguide system with the multiplexed grating proposed in this paper can effectively expand the field of view and improve the optical efficiency.
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Piperazic acid (Piz) is a nonproteinogenic amino acid possessing a rare nitrogen-nitrogen bond. However, little is known about how Piz is incorporated into nonribosomal peptides, including whether adenylation domains specific to Piz exist. In this study, we show that free piperazic acid is directly adenylated and then incorporated into the incarnatapeptin nonribosomal peptides through isotopic incorporation studies. We also use in vitro reconstitution to demonstrate adenylation of free piperazic acid with a three-domain nonribosomal peptide synthetase from the incarnatapeptin gene cluster. We furthermore use bioinformatics and site-directed mutagenesis to outline consensus sequences for the adenylation of piperazic acid, which can now be used for the prediction of gene clusters linked to piperazic-acid-containing peptides. Finally, we discover a fusion protein of a piperazate synthase and an adenylation domain, highlighting the close biosynthetic relationship of piperazic acid formation and its adenylation. Altogether, our work demonstrates the evolution of biosynthetic systems for the activation of free piperazic acid through adenylation, a pathway we suggest is likely to be employed in the majority of pathways to piperazic-acid-containing peptides.
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Peptídeo Sintases , Piridazinas , Nitrogênio , Peptídeo Sintases/metabolismo , Peptídeos/química , Piridazinas/química , Especificidade por SubstratoRESUMO
Semantic-rich speech emotion recognition has a high degree of popularity in a range of areas. Speech emotion recognition aims to recognize human emotional states from utterances containing both acoustic and linguistic information. Since both textual and audio patterns play essential roles in speech emotion recognition (SER) tasks, various works have proposed novel modality fusing methods to exploit text and audio signals effectively. However, most of the high performance of existing models is dependent on a great number of learnable parameters, and they can only work well on data with fixed length. Therefore, minimizing computational overhead and improving generalization to unseen data with various lengths while maintaining a certain level of recognition accuracy is an urgent application problem. In this paper, we propose LGCCT, a light gated and crossed complementation transformer for multimodal speech emotion recognition. First, our model is capable of fusing modality information efficiently. Specifically, the acoustic features are extracted by CNN-BiLSTM while the textual features are extracted by BiLSTM. The modality-fused representation is then generated by the cross-attention module. We apply the gate-control mechanism to achieve the balanced integration of the original modality representation and the modality-fused representation. Second, the degree of attention focus can be considered, as the uncertainty and the entropy of the same token should converge to the same value independent of the length. To improve the generalization of the model to various testing-sequence lengths, we adopt the length-scaled dot product to calculate the attention score, which can be interpreted from a theoretical view of entropy. The operation of the length-scaled dot product is cheap but effective. Experiments are conducted on the benchmark dataset CMU-MOSEI. Compared to the baseline models, our model achieves an 81.0% F1 score with only 0.432 M parameters, showing an improvement in the balance between performance and the number of parameters. Moreover, the ablation study signifies the effectiveness of our model and its scalability to various input-sequence lengths, wherein the relative improvement is almost 20% of the baseline without a length-scaled dot product.
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In order to discuss the "entropy weight method" for weighting various indicators in the comprehensive evaluation of Angelicae Sinensis Radix slices(ASR), the quality of ASR was comprehensively evaluated by entropy weight-based gray systematic theory and cluster analysis. In this study, the contents of ferulic acid, volatile oil, polysaccharide, alcohol extract, water extract, moisture, total ash and acid-insoluble ash in 44 batches of ASR from different sources were determined. The entropy weight method was used for objective weighting. With relative correlation(r_i) as a measure, a multi-index comprehensive evaluation model was constructed for the quality of ASR. The results showed that the relative correlation value of 44 batches of ASR ranged from 0.301 9 to 0.662 9. There were certain differences in the quality of ASR from different sources. The ASR S1-S8, traceable and standardized in processing techno-logy, showed a high relative correlation degree and high quality ranking, indicating that the implementation of systemic management of the production chain of Chinese herbal pieces was beneficial to the quality control of ASR. The quality evaluation results of 44 batches of ASR were consistent with those of traditional geo-authentic habitats for ASR and the mainstream varieties of ASR on market, and basically consistent with the results of cluster analysis. This study suggests that the gray systematic theory based on the entropy weighting method can be used for the quality evaluation of ASR. The objective weighting of the entropy weight method improves the reliability of the gray correlation method and the scientificity of ASR quality evaluation.
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Angelica sinensis , Medicamentos de Ervas Chinesas , Óleos Voláteis , Entropia , Raízes de Plantas , Reprodutibilidade dos TestesRESUMO
Hypoxia-inducible factors(HIFs)are the key transcription factors that sense and regulate cellular oxygen concentration in vivo. HIF-1 is composed of 2 subunits,α and ß,in which,the molecular regulatory mechanism of HIF-1α involves the main processes of its degradation and activation. The degradation of HIF-1α is regulated by oxygen-dependent pathways,including "von hippel-lindau protein(pVHL)-dependent pathway" and "pVHL-independent pathway". The activation of HIF-1α is regulated by oxygen-independent pathways,including mammalian target of rapamycin(mTOR)/eukaryotic initiation factor 4 E-binding protein 1(4 EBP1)/HIF-1α pathway,phosphatidylinositol 3-kinase(PI3 K)/proteirrserinc-threonine kinases(Akt)/HIF-1α pathway and silent information regulator1(Sirt1)/HIF-1α pathway. In recent years,based on the molecular regulatory mechanism of HIFs,Roxadustat,a new drug for the treatment of renal anemia has been developed. Besides, some macromolecular substances with similar pharmacological effect to HIFs have been found in the extracts from Chinese herbal medicine(CHM),such as emodin,notoginseng triterpenes,honokiol and clematichinenoside. These natural macromolecular substances play the regulatory roles in inflammatory response,epigenetic modification and auto-phagy. It is worth noting that,for common hypoxic-related diseases including diabetic kidney disease,HIFs-mediated "pyroptosis" may be a new target of CHMs for clearing dampness and heat and its representative classical prescriptions(Ermiao Pills)in treating inflammatory injury in cells and tissues.
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Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/farmacologia , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Proteínas Serina-Treonina Quinases , Fatores de TranscriçãoRESUMO
Childhood community-acquired pneumonia (CAP) is a common illness; however, comprehensive studies of hospitalizations for CAP among children in China based on prospective and multicenter data collection are limited. The aim of this investigation was to determine the respiratory pathogens responsible for CAP in hospitalized children. From January to December 2015, oropharyngeal swabs and blood serum were collected from hospitalized children with CAP symptoms ranging in age from 6 months to 14 years at 10 hospitals across China. We used immunofluorescence to detect antibodies for eight respiratory viruses and passive agglutination to detect specific IgM against Mycoplasma pneumoniae (M. pneumoniae). Of 1500 children presenting with CAP, 691 (46.1%) tested positive for at least one pathogen (virus or M. pneumoniae). M. pneumoniae (32.4%) was detected most frequently, followed by respiratory syncytial virus (11.5%), adenovirus (5.0%), influenza A virus (4.1 %), influenza B virus (3.4%), parainfluenza virus types 2 and 3 type (3.1 %), parainfluenza virus type 1 (2.9%), and human metapneumovirus (0.3%). Co-infections were identified in 128 (18.5%) of the 691 cases. These data provide a better understanding of viral etiology and M. pneumoniae in CAP in children between 6 months and 14 years in China. More study of the etiologic investigations that would further aid the management of pneumonia is required. With effective immunization for RSV, ADV, and M. pneumoniae infections, more than one-half of the pneumonia cases in this study could have been prevented.
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Infecções Comunitárias Adquiridas/epidemiologia , Hospitalização/estatística & dados numéricos , Pneumonia por Mycoplasma/epidemiologia , Pneumonia Viral/epidemiologia , Infecções Respiratórias/epidemiologia , Infecções por Adenoviridae/epidemiologia , Adolescente , Criança , Pré-Escolar , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/virologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Lactente , Masculino , Mycoplasma pneumoniae , Nasofaringe/virologia , Estudos Prospectivos , Vírus Sincicial Respiratório Humano , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologiaRESUMO
BACKGROUND: Postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG) is one of the most common complications that can contribute to an increased risk of mortality, particularly in older patients. The identification of predictors of POAF after CABG could impact patient care. This study aims to determine the risk factors of POAF in patients ≥60 years old who underwent isolated on-pump coronary artery bypass grafting (ONCAB) in order to provide a basis for the prevention and treatment of POAF after ONCAB. METHODS: Between October 2011 and November 2015, a total of 304 patients ≥60 years old underwent isolated ONCAB in our department. The patients were divided into 2 groups, the AF group and the non-AF group, according to the occurrence of POAF. A retrospective analysis was performed on the general characteristics and perioperative data of the patients. Logistic regression analysis was used to identify the predictors of POAF after ONCAB in patients ≥60 years old. RESULTS: The incidence of POAF after ONCAB in patients ≥60 years old was 23.36% (71/304). Statistically significant differences were observed in patients' age, history of hypertension, left atrium diameter, European System for Cardiac Operative Risk Evaluation (EuroSCORE) I and II, and the highest level of serum creatinine after operation (all P < .05). Logistic regression analyses showed that a history of hypertension (OR = 2.575, CI 1.208-5.488, P = .014), left atrium diameter (OR = 1.105, CI 1.047-1.167, P = .000) and EuroSCORE I score (OR = 1.132, CI 1.001-1.279, P = .048) were independent risk factors for POAF after ONCAB in patients ≥60 years old. CONCLUSION: The occurrence of POAF after isolated ONCAB in patients ≥60 years old was affected by many risk factors; a history of hypertension, the left atrium diameter and the EuroSCORE I score were all predictors of POAF.
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Fibrilação Atrial/epidemiologia , Ponte de Artéria Coronária/efeitos adversos , Doença da Artéria Coronariana/cirurgia , Complicações Pós-Operatórias , Medição de Risco , Idoso , Fibrilação Atrial/etiologia , China/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de TempoRESUMO
OBJECTIVE: To evaluate the safety and efficacy of cryoablation (CYA) and microwave ablation (MWA) in the treatment of patients with perivascular hepatocellular carcinoma (HCC). METHODS: Patients with perivascular HCC who underwent computed tomography (CT)-guided percutaneous CYA or MVA treatment in our hospital from August 2009 to March 2019 were included. Propensity score matching (PSM) was performed to adjust for potential baseline differences in the two groups. The technical success rate (TS), complications, and visual analog scale (VAS) were analyzed. The overall survival (OS) was evaluated using Kaplan-Meier curves and Cox proportional hazards models. RESULTS: After PSM, 32 patients from each group were selected. The technical success rate was 94 % for CYA and 91 % for MWA, and 13 patients developed recurrence (CYA, n = 5, 2 local, 3 distant; MWA, n = 8, 6 local, 2 distant). There were no significant differences in OS (36-months OS: CYA 53.1 % vs, MWA 40.6 %; P = 0.191). No intraoperative deaths or complication-related deaths were observed, and 19 patients (CYA, n = 8; MWA, n = 11) experienced complications (P = 0.435). The VAS in the MWA group (5.38 ± 1.21) was significantly higher than that in the CYA group (2.22 ± 0.87; P < 0.001). CONCLUSIONS: While CYA has equal safety and high primary efficacy as MWA in the treatment of perivascular HCC, it is associated with less periprocedural pain.
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Carcinoma Hepatocelular , Ablação por Cateter , Criocirurgia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Micro-Ondas/uso terapêutico , Pontuação de Propensão , Resultado do Tratamento , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ablação por Cateter/métodosRESUMO
Azaserine (1) is a natural product and nonproteinogenic amino acid containing a diazo group. Here we report the biosynthetic gene cluster for 1 from Glycomyces harbinensis. We then use isotopic feeding, gene deletion, and biochemical experiments to support a pathway whereby hydrazinoacetic acid (2) and a peptidyl carrier protein-loaded serine (3) are intermediates on route to the final natural product 1.
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Azasserina , Produtos Biológicos , Serina , Família Multigênica , HidrazinasRESUMO
OBJECTIVE: To evaluate the clinical efficacy and safety of external application of Chinese herbal medicine (ex-CHM) for psoriasis vulgaris (PV). METHODS: Different search portals, including the China National Knowledge Infrastructure Database, China Science and Technology Journal Database, Wanfang, SinoMed, clinicaltrials, PubMed, Cochrane Library, and Cochrane Central Register of Controlled Trials, were searched for randomized controlled trials (RCTs) that compared the ex-CHM intervention with other treatment protocols for PV, with available data as of November 25, 2020. The Review Manager 5.3 software was used for analysis. RESULTS: Nineteen RCTs involving 1988 participants were included, of which twelve RCTs qualified for the Meta-analysis. The results showed that the addition of CHM bath to narrow-band ultraviolet B (NB-UVB) had a higher response rate [RR = 1.29; 95% CI (1.19, 1.40); P < 0.000 01]; lower psoriasis area severity index (PASI) [MD = -3.15; 95% CI (-4.79, -1.52); P = 0.000 2)], adverse reactions rate [RR = 0.32; 95% CI (0.15, 0.66); P = 0.002], and recurrence rate [RR = 0.48; 95% CI (0.30, 0.79); P=0.004] than NB-UVB alone. The addition of CHM fumigation to NB-UVB also showed a higher response rate [RR = 1.29; 95% CI (1.11, 1.49); P = 0.000 7] and lower adverse reactions rate [RR = 0.44; 95% CI (0.24, 0.79); P=0.006]. In addition, CHM bath could reduce the adverse reactions induced by 308 nm excimer laser and improve patients' quality of life better than phototherapy. CHM fumigation could improve the efficacy of calcipotriol ointment and reduce the adverse reactions. CHM fumigation combined with external washing plus acitretin showed better results than using acitretin alone. No statistical difference was observed between CHM external washing and calcipotriol ointment or CHM ointment and retinoic acids. CONCLUSIONS: Current evidence showed that CHM bath and fumigation appeared to be efficient and safe for PV treatment. However, no definite conclusion could be drawn due to the low quality of included studies and thus more well-designed studies are needed for further assessment.
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Medicamentos de Ervas Chinesas , Psoríase , Acitretina/uso terapêutico , Medicamentos de Ervas Chinesas/efeitos adversos , Humanos , Pomadas/uso terapêutico , Psoríase/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
OBJECTIVE: To collect visualized proof of Tianmagouteng particles (TMGTP) in alleviating cognitive dysfunction and to explore its effects on brain activity in spontaneously hypertensive rats (SHRs) with hyperactivity of liver-yang (Gan Yang Shang Kang, GYSK). METHODS: Sixteen SHRs were randomized into treatment group and non-treatment. The SHR with GYSK was induced by gavaging aconite decoction (10mL/kg at 0.2g/mL). After the SHR models were prepared, the rats in the treatment group were administered TMGTP (10mL/kg) once a day for 14days.The rats in the non-treatment group or normal rats (control group) received an equivalent volume of saline. Morris water maze test was conducted before and after the treatment to observe cognitive function. Fluorine 18-deoxy glucose [F-18]FDG micro-PET brain imaging scans was performed after treatment. Data were analyzed with two-sample t-test (P<0. 001) using SPM2 image analysis software. RESULTS: Compared with the non-treatment group, the escape latency significantly decreased but the frequency of entrance into the target zone significantly increased in the treatment group. Consistent with the alteration of cognitive functions, TMGTP induced strong brain activity in the following sites: right dorsolateral nucleus and ventrolateral nucleus of thalamus, amygdala, left met thalamus, cerebellum leaflets, original crack, front cone crack, loop-shaped leaflets; but deactivation of right medial frontal gyrus, bilateral corpus callosum, hippocampus, and left dentate gyrus. CONCLUSION: TMGTP could alleviate cognitive dysfunction in SHRs with GYSK, which was possibly by inducing alteration of glucose metabolism in different brain regions with corresponding functions.
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Cognição/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Hipertensão/tratamento farmacológico , Fígado/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Fluordesoxiglucose F18 , Glucose/metabolismo , Fígado/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Tomografia por Emissão de Pósitrons , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-DawleyRESUMO
The dicistrovirus Cricket Paralysis virus contains a unique dicistronic RNA genome arrangement, encoding two main open reading frames that are driven by distinct internal ribosome entry sites (IRES). The intergenic region (IGR) IRES adopts an unusual structure that directly recruits the ribosome and drives translation of viral structural proteins in a factor-independent manner. While structural, biochemical, and biophysical approaches have provided mechanistic details into IGR IRES translation, these studies have been limited to in vitro systems and little is known about the behavior of these IRESs during infection. Here, we examined the role of previously characterized IGR IRES mutations on viral yield and translation in CrPV-infected Drosophila S2 cells. Using a recently generated infectious CrPV clone, introduction of a subset of mutations that are known to disrupt IRES activity failed to produce virus, demonstrating the physiological relevance of specific structural elements within the IRES for virus infection. However, a subset of mutations still led to virus production, thus revealing the key IRES-ribosome interactions for IGR IRES translation in infected cells, which highlights the importance of examining IRES activity in its physiological context. This is the first study to examine IGR IRES translation in its native context during virus infection.
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Dicistroviridae/genética , RNA Viral/genética , Animais , Sequência de Bases , Linhagem Celular , Drosophila melanogaster , Genoma Viral , Sítios Internos de Entrada Ribossomal , Mutação , Biossíntese de Proteínas , Proteínas Estruturais Virais/biossíntese , Proteínas Estruturais Virais/genética , Replicação ViralRESUMO
Qili qiangxin (QL) capsule is a traditional Chinese medicine that is widely used for the treatment of patients with chronic heart failure (CHF) of all etiologies, although the exact mechanisms of action remain unclear. CHF leads to pulmonary vascular remodelling and thickening of the alveolar-capillary barrier that may be important mechanisms in the poor clinical outcome in patients with end-stage heart failure. We examined whether QL could improve lung injury in ischemic CHF by reducing lung remodeling. Rats with myocardial infarct received QL (1.0 g/kg/day) for 4 weeks. Echocardiographic and morphometric measurements were obtained followed by echocardiography, histological staining, and immunohistochemical analysis of lung sections. CHF caused significant lung structural remodeling evidenced by collagen deposition and thickening of the alveolar septa after myocardial infarct that were greatly improved by QL. Lung weight increased after infarct with no evidence of pulmonary edema and was normalized by QL. QL also reduced lung transforming growth factor-ß1 (TGF-ß1), p-Smad3, tumor necrosis factor-α (TNF-α), and Toll-like receptor-4 (TLR4) expression. Thus, QL reduces lung remodeling associated with CHF, mainly by suppressing the TGF-ß1/Smad3 signaling pathway. The mechanism may also involve inhibition of TLR4 intracellular signaling.