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Introducing dynamic behavior into periodic frameworks has borne fruit in the form of flexible porous crystals. The detailed molecular design of frameworks in order to control their collective dynamics is of particular interest, for example, to achieve stimulus-induced behavior. Herein, by varying the degree of rigidity of ditopic pillar linkers, two isostructural flexible metal-organic frameworks (MOFs) with common rigid supermolecular building bilayers were constructed. The subtle substitution of single (in bibenzyl-4,4'-dicarboxylic acid; H2BBDC) with double (in 4,4'-stilbenedicarboxylic acid; H2SDC) C-C bonds in pillared linkers led to markedly different flexible behavior of these two MOFs. Upon the removal of guest molecules, both frameworks clearly show reversible single-crystal-to-single-crystal transformations involving the cis-trans conformation change and a resulting swing of the corresponding pillar linkers, which gives rise to Flex-Cd-MOF-1a and Flex-Cd-MOF-2a, respectively. Strikingly, a more favorable gas-induced dynamic behavior in Flex-Cd-MOF-2a was verified in detail by stepwise C3H6/C3H8 sorption isotherms and the corresponding in situ powder X-ray diffraction experiments. These insights are strongly supported by molecular modeling studies on the sorption mechanism that explores the sorption landscape. Furthermore, a consistency between the macroscopic elasticity and microscopic flexibility of Flex-Cd-MOF-2 was observed. This work fuels a growing interest in developing MOFs with desired chemomechanical functions and presents detailed insights into the origins of flexible MOFs.
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Metal-organic frameworks (MOFs) have been recognized as a potential platform for the development of tunable luminophores owing to their highly modulable structures and components. Herein, two MOF luminophores based on Cd(II) ions, 1,3,5-tri(4-pyridinyl)benzene (TPB), and 1,4-dicarboxybenzene (H2BDC) were constructed. The directed assembly of the metal ions and organic linkers results in [Cd2(BDC)2(TPB)(H2O)]·x(solvent) (MOF-1) featuring TPB-based blue fluorescence centered at 425 nm. By introducing anthracene as the structure directing agent (SDA) for assembly regulation, [Cd2(BDC)(TPB)2(NO3)2]·x(solvent) (MOF-2) was obtained, which reveals anthracene feeding-dependent high tunable emission in the 517-650 nm range. Detailed components, photophysical properties, and structural characteristics investigations of MOF-2 indicate the TPB and NO3- interactions as the origin of its redshifted emission compared with that of MOF-1. Furthermore, the fluorescence of MOF-2 was found to be regulatable by the anthracene feeding based on the SDA-determined crystallinity of the crystalline sample. All these results provided a unique example of the structural and fluorescence regulation of MOF luminophores.
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The hierarchical porous metal-organic framework (HP-MOF) has emerged as a hot topic in porous materials in consideration of their advantages in storage capacity and catalysis performance. Herein, we report the construction and property investigation of a series of HP-MOFs. A series of isoreticular microporous MOFs featuring the pacs topology network based on 2,4,6-tris(4-pyridyl)-1,3,5-triazine and different carboxylic acid ligands are found to be potential precursors to construct HP-MOFs. Through the decarboxylation of carboxylate ligands at high temperatures, a hierarchical porous structure could be obtained with the reservation of a crystalline framework. The formation of hierarchical pores is highly dependent on the structural and component nature (carboxylate ligands and metal centers) of the pristine MOF and the pyrolysis conditions (temperature and treatment time), indicating the highly tunable hierarchical pore characteristic of the HP-MOFs. By taking advantage of the increased pore volume and more exposed activation sites, the HP-MOFs reveal enhanced anionic dye adsorption capacity (800 mg·g-1 for Congo red and 140 mg·g-1 for methyl blue) and catalytic activity toward electrocatalytic oxygen reduction reaction (overpotential of 0.302 V at a current density of 10 mA·cm-2, 51 mV lower than that of the pristine MOF).
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AIM: The aim of this study was to use a metabonomics approach to identify potential biomarkers of exhaled breath condensate (EBC) for predicting the prognosis of acute-on-chronic liver failure (ACLF). METHODS: Using liquid chromatography mass spectrometry, EBC metabolites of ACLF patients surviving without liver transplantation (n = 57) and those with worse outcomes (n = 45), and controls (n = 15) were profiled from a specialized liver disease center in Beijing. The metabolites were used to identify candidate biomarkers, and the predicted performance of potential biomarkers was tested. RESULTS: Forty-one metabolites, involving glycerophospholipid metabolism, sphingolipid metabolism, arachidonic acid metabolism, and amino acid metabolism, as candidate biomarkers for discriminating the different outcomes of ACLF were selected. A prognostic model was constructed by a panel of four metabolites including phosphatidylinositol [20:4(5Z,8Z,11Z,14Z)/13:0], phosphatidyl ethanolamine (12:0/22:0), L-metanephrine and ethylbenzene, which could predict the worse prognosis in ACLF patients with sensitivity (84.4%) and specificity (89.5%) (area under the receiver operating characteristic curve [AUC] = 0.859, 95% confidence interval [CI] = 0.787-0.931). Compared with Model for End-Stage Liver Disease (MELD) score (AUC = 0.639, 95% CI = 0.526-0.753) and MELD-sodium (MELD-Na) score (AUC = 0.692, 95% CI = 0.582-0.803), EBC-associated metabolite signature model could better predict worse outcomes in patients with ACLF (p < 0.05). Using the MELD-Na score and EBC metabolite signatures, a decision tree model was built for predicting the prognosis of ACLF identified on logistic regression analyses (AUC = 0.906, 95% CI = 0.846-0.965). CONCLUSION: EBC metabolic signatures show promise as potential biomarkers for predicting worse prognosis of ACLF.
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OBJECTIVE: To study the risk factors for the first ventilator weaning failure and the relationship between the weaning failure and prognosis in preterm infants receiving invasive mechanical ventilation. METHODS: A retrospective analysis was performed for the preterm infants who were admitted to the Neonatal Intensive Care Unit of Peking University Third Hospital and received mechanical ventilation within 72 hours after birth. According to whether reintubation was required within 72 hours after the first weaning, the infants were divided into a successful weaning group and a failed weaning group. RESULTS: A total of 282 preterm infants were enrolled, and there were 43 infants (15.2%) in the failed weaning group. Compared with the successful weaning group, the failed weaning group had significantly lower gestational age and birth weight (P < 0.05), a significantly higher rate of intubation in the delivery room (P < 0.05), and a significantly higher proportion of infants with patent ductus arteriosus (PDA; diameter ≥ 2.5 mm) (P < 0.05). Use of ≥ 2 vasoactive agents before ventilator weaning (OR=2.48, 95%CI:1.22-5.03, P < 0.05) and PDA (≥ 2.5 mm) (OR=4.54, 95%CI:2.02-10.24, P < 0.05) were risk factors for ventilator weaning failure. Compared with the successful weaning group, the failed weaning group had significantly higher incidence rates of ventilator-associated pneumonia, moderate-to-severe bronchopulmonary dysplasia, and sepsis (P < 0.05). The oxygen inhalation time and hospital stay in the failed weaning group were significantly longer than those in the successful weaning group (P < 0.05). CONCLUSIONS: Use of ≥ 2 vasoactive agents before ventilator weaning and PDA (≥ 2.5 mm) are risk factors for ventilator weaning failure, and ventilator weaning failure may be associated with adverse outcomes in hospitalized preterm infants.
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Permeabilidade do Canal Arterial , Síndrome do Desconforto Respiratório do Recém-Nascido , Permeabilidade do Canal Arterial/terapia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Respiração Artificial , Estudos Retrospectivos , Fatores de Risco , Desmame do RespiradorRESUMO
BACKGROUND: Cry8-like from Bacillus thuringiensis (Bt) encodes an insecticidal crystal (Cry) protein. Holotrichia parallela (Coleoptera: Scarabaeoidae), commonly known as the dark black chafer, is a troublesome pest of soybean (Glycine max). To test whether cry8-like can confer resistance against H. parallela to soybean, we introduced cry8-like from the Bt strain HBF-18 into soybean cultivar Jinong 28. RESULTS: Quantitative reverse transcription-PCR analysis demonstrated that cry8-like was expressed most highly in soybean leaves. In addition, Southern blot assays revealed that one copy of the integrated fragment was present in the transformed plants. Eight independent cry8-like transgenic lines were subsequently fed on by H. parallela. Under H. parallela feeding stress, the survival rates of the non-transgenic plants were 92% lower than those of the transgenic plants. The mortality rate of H. parallela increased when the larvae fed on the roots of T1 transgenic soybean plants. Moreover, the surviving larvae were deformed, and their growth was inhibited. CONCLUSIONS: Collectively, our data suggest that transgenic soybean plants expressing the cry8-like gene are more resistant to H. parallela than non-transgenic plants and that transgenic expression of the cry8-like gene may represent a promising strategy for engineering pest tolerance. The events generated in this study could thus be utilized in soybean breeding programs.
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Bacillus thuringiensis/metabolismo , Toxinas Bacterianas/metabolismo , Besouros/microbiologia , Besouros/patogenicidade , Glycine max/parasitologia , Proteínas Hemolisinas/metabolismo , Plantas Geneticamente Modificadas/parasitologia , Animais , Toxinas Bacterianas/genética , Proteínas Hemolisinas/genética , Controle Biológico de VetoresRESUMO
BACKGROUND: Toxoplasma gondii, an intracellular apicomplexan protozoan parasite, can infect almost all warm-blooded animals. The aim of the present study was to investigate T. gondii oocyst-driven infection in pigs, chickens and humans in Jilin province, northeastern China. RESULTS: The serum samples of pigs, chickens and humans were sampled and tested by indirect enzyme-linked immunosorbent assays (ELISAs) using dense granule antigen GRA7, oocyst-specific protein OWP8, and sporozoite-specific protein CCp5A, respectively. Results showed a prevalence of 16.7% by GRA7-ELISA, and 12.2% by OWP8- and CCp5A-ELISA in pigs; 10.4% by GRA7-ELISA, 13.5% by OWP8-ELISA, and 9.4% by CCp5A-ELISA in chickens; and 14.2% by GRA7-ELISA, 3.6% by OWP8-ELISA, and 3.0% by CCp5A-ELISA in humans. No significant differences were observed between T. gondii seroprevalence in pigs and chickens among the three antigens-based ELISAs (P > 0.05). However, there were significant differences between T. gondii seroprevalence rates in humans (P < 0.05). These findings demonstrated a low prevalence of T. gondii oocyst-driven infection in humans, a medium prevalence in pigs, and a high prevalence in chickens. CONCLUSIONS: The present study demonstrated that different oocyst-driven infection rates in different animal species, which would help to design effective strategies to prevent T. gondii transmission. To our knowledge, this is the first study to differentiate T. gondii infective forms in pigs, chickens and humans in China.
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Doenças das Aves Domésticas/parasitologia , Doenças dos Suínos/parasitologia , Toxoplasmose/epidemiologia , Animais , Antígenos de Protozoários/sangue , Galinhas , China/epidemiologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Oocistos , Doenças das Aves Domésticas/epidemiologia , Proteínas de Protozoários/sangue , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologiaRESUMO
Evidence has demonstrated that sleep-related memory consolidation declines in ageing. However, little is known about age-related changes to sleep-related emotional memory consolidation, especially when considering the positivity effect observed in older adults. In the present study, we sought to explore whether there is a positive emotional bias in sleep-related memory consolidation among healthy older adults. Young and older adults were randomly assigned either into a sleep or wake condition. All participants encoded positive, negative, and neutral stimuli and underwent recognition tests immediately (test 1), after a 12-hour sleep/wake interval (test 2), and 3 days after test 2 (test 3). Results showed that age-related differences of sleep beneficial effect were modulated by emotion valence. In particular, sleep selectively enhanced positive memory in older adults, while in young adults sleep beneficial effect was manifested in neutral memory. Moreover, the sleep beneficial effect can be maintained at least 3 days in both young and older adults. These findings suggest that older adults had preserved but positive bias of sleep-related memory consolidation, which could be one of the underlying mechanisms for their generally better emotional well-being in daily life. These findings highlight the dynamic interplay among sleep and emotional memory in older adults.
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Envelhecimento , Emoções , Consolidação da Memória/fisiologia , Sono/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Psicológico , Adulto JovemRESUMO
OBJECTIVE: To investigate the quality of life of children with atopic dermatitis (AD) and their families, and to assess the changes in quality of life after treatment. METHODS: The Infants' Dermatitis Quality of Life Index (IDQOL), Children's Dermatology Life Quality Index (CDLQI), and Dermatitis Family Impact (DFI) questionnaires were used to evaluate quality of life in 109 children with AD and 55 normal children. The Severity Scoring of Atopic Dermatitis (SCORAD) was used to evaluate disease severity. The children were given external application of glucocorticoids according to the SCORAD index, and the clinical outcome and changes in quality of life were observed after 3 months of treatment. RESULTS: The three items in both IDQOL and CDLQI questionnaires with higher scores were itching/scratching, mood problems, and sleeping disturbance in the AD patients. Sleeping disturbance, fatigue and mood problems were the three items in the DFI questionnaire with higher scores. There was a positive correlation between IDQOL/CDLQI score and SCORAD index (r=0.358, 0.386 respectively; P<0.05). In the younger group (1-4 years), there was a positive correlation between DFI score and SCORAD index (r=0.297; P<0.05). After treatment the severity of AD and quality of life in the children and their families (P<0.05) were significantly improved. CONCLUSIONS: AD has an adverse effect on quality of life in children with AD and their families. Topical glucocorticoids may control the symptoms of AD and improve the quality of life in children and their families.
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Dermatite Atópica/psicologia , Qualidade de Vida , Criança , Pré-Escolar , Dermatite Atópica/terapia , Feminino , Humanos , Lactente , Masculino , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
Background: The primary aim of this study is to investigate the correlation between serum levels of fibrinogen-to-prealbumin ratio (FPR) and C-reactive protein-to-prealbumin ratio (CPR) and prognostic outcomes among patients with severe fever with thrombocytopenia syndrome (SFTS). SFTS, characterized by elevated mortality rates, represents a substantial public health challenge as an emerging infectious disease. Methods: The study included 159 patients with SFTS. Clinical and laboratory data were compared between the survival and death groups. Univariate and multivariate logistic regression analysis were utilized to identify independent risk factors for mortality. The predictive efficacy of FPR and CPR was evaluated using receiver operating characteristic (ROC) curve. Survival analysis was conducted using the Kaplan-Meier curve and the log-rank test was employed for comparison. Results: The death group exhibited significantly elevated levels of FPR and CPR compared to the survival group (P < 0.05). Multivariate logistic regression analysis confirmed that both FPR and CPR independently correlated with a poorer prognosis among patients with SFTS. The ROC curve analysis indicated that FPR and CPR had superior predictive capabilities compared to C-reactive protein and fibrinogen. Kaplan-Meier survival analysis demonstrated that patients with SFTS who have FPR > 0.045 (log-rank test; χ2 = 17.370, P < 0.001) or CPR > 0.05 (log-rank test; χ2 = 19.442, P < 0.001) experienced significantly lower survival rates within a 30-day follow-up period. Conclusion: Elevated levels of FPR and CPR serve as distinct risk factors for mortality among patients with SFTS, indicating their potential to predict an unfavorable prognosis in these patients.
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Proteína C-Reativa , Fibrinogênio , Pré-Albumina , Curva ROC , Febre Grave com Síndrome de Trombocitopenia , Humanos , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Masculino , Feminino , Fibrinogênio/análise , Fibrinogênio/metabolismo , Prognóstico , Pessoa de Meia-Idade , Idoso , Febre Grave com Síndrome de Trombocitopenia/sangue , Febre Grave com Síndrome de Trombocitopenia/mortalidade , Pré-Albumina/análise , Pré-Albumina/metabolismo , Biomarcadores/sangue , Fatores de Risco , Adulto , Phlebovirus , Estimativa de Kaplan-Meier , Estudos RetrospectivosRESUMO
OBJECTIVES: Understanding the influence of cognitive activity on subsequent sleep has both theoretical and applied implications. This study aims to investigate the effect of pre-sleep cognitive activity, in the context of avoiding emotional interference, on macro-sleep and sleep spindles. METHODS: In a within-subjects design, participants' sleep electroencephalography was collected in both the with and without pre-sleep cognitive activity conditions. Subsequent macro-sleep (i.e., sleep stage distribution and sleep parameters) and spindle characteristics (i.e., density, amplitude, duration, and frequency) were analyzed. In addition, a novel machine learning framework (i.e., deep neural network, DNN) was used to discriminate between cognitive activity and control conditions. RESULTS: There were no significant differences in macro-sleep and sleep spindles between the cognitive activity and control conditions. Spindles-based DNN models achieved over 96% accuracy in differentiating between the two conditions, with fast spindles performing better than full-range and slow spindles. CONCLUSIONS: These results suggest a weak but positive effect of pre-sleep cognitive activity on subsequent sleep. It sheds light on a possible low-cost and easily accessible sleep intervention strategy for clinical and educational purposes.
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Transtornos do Sono-Vigília , Sono , Humanos , Fases do Sono , Eletroencefalografia , Redes Neurais de Computação , CogniçãoRESUMO
The self-trapped state (STS) of the interlayer exciton (IX) has aroused enormous interest owing to its significant impact on the fundamental properties of the van der Waals heterostructures (vdWHs). Nevertheless, the microscopic mechanisms of STS are still controversial. Herein, we study the corrections of the binding energies of the IXs stemming from the exciton-interface optical phonon coupling in four kinds of vdWHs and find that these IXs are in the STS for the appropriate ratio of the electron and hole effective masses. We show that these self-trapped IXs could be classified into type I with the increasing binding energy in the tens of millielectronvolts range, which are very agreement with the red-shift of the IX spectra in experiments, and type II with the decreasing binding energy, which provides a possible explanation for the blue-shift and broad line width of the IX's spectra at low temperatures. Moreover, these two types of exciton states could be transformed into each other by adjusting the structural parameters of vdWHs. These results not only provide an in-depth understanding for the self-trapped mechanism but also shed light on the modulations of IXs in vdWHs.
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BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with a rising incidence worldwide. The prognosis of HCC patients after radical resection remains poor. Radiomics is a novel machine learning method that extracts quantitative features from medical images and provides predictive information of cancer, which can assist with cancer diagnosis, therapeutic decision-making and prognosis improvement. AIM: To develop and validate a contrast-enhanced computed tomography-based radiomics model for predicting the overall survival (OS) of HCC patients after radical hepatectomy. METHODS: A total of 150 HCC patients were randomly divided into a training cohort (n = 107) and a validation cohort (n = 43). Radiomics features were extracted from the entire tumour lesion. The least absolute shrinkage and selection operator algorithm was applied for the selection of radiomics features and the construction of the radiomics signature. Univariate and multivariate Cox regression analyses were used to identify the independent prognostic factors and develop the predictive nomogram, incorporating clinicopathological characteristics and the radiomics signature. The accuracy of the nomogram was assessed with the concordance index, receiver operating characteristic (ROC) curve and calibration curve. The clinical utility was evaluated by decision curve analysis (DCA). Kaplan-Meier methodology was used to compare the survival between the low- and high-risk subgroups. RESULTS: In total, seven radiomics features were selected to construct the radiomics signature. According to the results of univariate and multivariate Cox regression analyses, alpha-fetoprotein (AFP), neutrophil-to-lymphocyte ratio (NLR) and radiomics signature were included to build the nomogram. The C-indices of the nomogram in the training and validation cohorts were 0.736 and 0.774, respectively. ROC curve analysis for predicting 1-, 3-, and 5-year OS confirmed satisfactory accuracy [training cohort, area under the curve (AUC) = 0.850, 0.791 and 0.823, respectively; validation cohort, AUC = 0.905, 0.884 and 0.911, respectively]. The calibration curve analysis indicated a good agreement between the nomogram-prediction and actual survival. DCA curves suggested that the nomogram had more benefit than traditional staging system models. Kaplan-Meier survival analysis indicated that patients in the low-risk group had longer OS and disease-free survival (all P < 0.0001). CONCLUSION: The nomogram containing the radiomics signature, NLR and AFP is a reliable tool for predicting the OS of HCC patients.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Nomogramas , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , alfa-FetoproteínasRESUMO
Metal halide perovskites quantum dots (MHPQDs) have aroused enormous interest in the photovoltaic and photoelectric disciplines because of their marvelous properties and size characteristics. However, one of the key problems of how to systematically analyze charge carriers trapped by defects is still a challenging task. Here, we study multiphonon processes of the charge carrier trapping by various defects in MHPQDs based on the well-known Huang-Rhys model, in which a method of a full-configuration defect, including different defect species with variable depth and lattice relaxation strength, is developed by introducing a localization parameter in the quantum defect model. With the help of this method, these fast trapping channels for charge carriers transferring from the quantum dot ground state to different defects are found. Furthermore, the dependence of the trapping time on the radius of quantum dot, the defect depth, and temperature is given. These results not only enrich the knowledge of charge carrier trapping processes by defects, but also bring light to the designs of MHPQDs-based photovoltaic and photoelectric devices.
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Long-term exposure to ultraviolet light induces photoaging and may eventually increase the risk of skin carcinogenesis. Rare minor ginsenosides isolating from traditional medicine Panax (ginseng) have shown biomedical efficacy as antioxidation and antiphotodamage agents. However, due to the difficulty of component extraction and wide variety of ginsenoside, the identification of active antiphotoaging ginsenoside remains a huge challenge. In this study, we proposed a novel in silico approach to identify potential compound against photoaging from 82 ginsenosides. Specifically, we calculated the shortest distance between unknown and known antiphotoaging ginsenoside set in the chemical space and applied chemical structure similarity assessment, drug-likeness screening, and ADMET evaluation for the candidates. We highlighted three rare minor ginsenosides (C-Mc, Mx, and F2) that possess high potential as antiphotoaging agents. Among them, C-Mc deriving from American ginseng (Panax quinquefolius L.) was validated by wet-lab experimental assays and showed significant antioxidant and cytoprotective activity against UVB-induced photodamage in human dermal fibroblasts. Furthermore, system pharmacology analysis was conducted to explore the therapeutic targets and molecular mechanisms through integrating global drug-target network, high quality photoaging-related gene profile from multiomics data, and skin tissue-specific expression protein network. In combination with in vitro assays, we found that C-Mc suppressed MMP production through regulating the MAPK/AP-1/NF-κB pathway and expedited collagen synthesis via the TGF-ß/Smad pathway, as well as enhanced the expression of Nrf2/ARE to hold a balance of endogenous oxidation. Overall, this study offers an effective drug discovery framework combining in silico prediction and in vitro validation, uncovering that ginsenoside C-Mc has potential antiphotoaging properties and might be a novel natural agent for use in oral drug, skincare products, or functional food.
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Ginsenosídeos/uso terapêutico , Panax/química , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Ginsenosídeos/farmacologia , HumanosRESUMO
Quantum defects have been shown to play an essential role in nonradiative recombination in metal halide perovskites (MHPs). Nonetheless, the processes of charge transfer assisted by defects are still ambiguous. Herein, we theoretically study the nonradiative multiphonon processes among different types of quantum defects in MHPs using Markvart's model for the induced mechanisms of electron-electron and electron-phonon interactions. We find that the charge carrier can transfer between the neighboring levels of the same type of shallow defects by multiphonon processes, but it will be distinctly suppressed with an increase in the defect depth. For the nonradiation multiphonon transitions between donor- and acceptor-like defects, the processes are very fast and not sensitive to the defect depth, which provides a possible explanation for the phenomenon of blinking of photoluminescence spectra. We also discuss the temperature dependence of these multiphonon processes and find that their variational trends depend on the comparison of the Huang-Rhys factor with the emitted phonon number. These theoretical results not only fill some of the gaps in defect-assisted nonradiative processes in the perovskite materials but also provide deeper physical insights into producing higher-performance perovskite-based devices.
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We propose a theoretical model for studying the effective velocities of polaron spin states in monolayer transition metal dichalcogenides (TMDS) on the substrate. It is found that the effective velocity of polaron shows the splitting with different magnitudes due to the Rashba spin-orbit coupling, which results in the reversed distribution of the effective velocities of polaron spin states. Moreover, the reversed points depend on the truncated wave-vector of optical phonon and can be modulated by the polarity of substrate and the internal distance between monolayer TMDS and substrate. These theoretical results enlighten some simple ways to distinguish and modulate the polaron spin states in two-dimensional heterostructures.
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BACKGROUND: The hospital-acquired influenza (HAI) were usually contributed to severe outcomes among the inpatients. Here, we performed a meta-analysis to summarize and quantify the epidemiological and clinical characteristics of HAI. METHODS: We performed a literature search thorough PubMed, Web of Science, Cochrane Library, Embase, Scopus and China National Knowledge Infrastructure (CNKI), and Wanfang databases for observational studies. Random/fix-effects models were used to obtain pooled proportion, odds ratio (OR), and weighted mean difference (WMD). RESULTS: A total of 14 studies involving 1483 HAI and 71849 non-hospital-acquired influenza infections (NHAI) cases were included.The proportion of the HAI among the influenza cases was 11.38% (95% confidence interval [CI]: 5.19%-19.55%) and it was increased after 2012 (6.15% vs 12.72%). The HAI cases were significantly older (WMDâ=â9.51, 95% CI: 0.04-18.98) and the patients with chronic medical diseases were at increased risk of HAI (ORâ=â1.85, 95% CI: 1.57-2.19). Among them, metabolic disorders (ORâ=â8.10, 95% CI: 2.46-26.64) ranked the highest danger, followed by malignancy (ORâ=â3.18, 95% CI: 2.12-4.76), any chronic diseases (ORâ=â2.81, 95% CI: 1.08-9.31), immunosuppression (ORâ=â2.13, 95% CI: 1.25-3.64), renal diseases (ORâ=â1.72, 95% CI:1.40-2.10), heart diseases (ORâ=â1.52, 95% CI: 1.03-1.44), and diabetes (ORâ=â1.22, 95% CI: 1.03-1.44). The HAI cases were more likely to experience longer hospital stay (WMDâ=â10.23, 95% CI: 4.60-15.85) and longer intensive care unit (ICU) stay (WMDâ=â2.99, 95% CI: 1.50-4.48). In the outcomes within 30 days, those population was still more likely to receive hospitalization (ORâ=â6.55, 95% CI: 5.19-8.27), death in hospital (ORâ=â1.99, 95% CI: 1.65-2.40) but less likely to discharged (ORâ=â0.20, 95% CI: 0.16-0.24). CONCLUSION: The proportion of the HAI among the influenza cases was relatively high. Reinforcement of the surveillance systems and vaccination of the high-risk patients and their contacts are necessary for the HAI control.
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Infecção Hospitalar/epidemiologia , Hospitalização/estatística & dados numéricos , Vírus da Influenza A , Influenza Humana/epidemiologia , Vigilância da População , Estudos de Casos e Controles , Infecção Hospitalar/virologia , Estudos Transversais , Feminino , Humanos , Incidência , Influenza Humana/etiologia , Masculino , Razão de ChancesRESUMO
OBJECTIVES: This study was aimed to explore the mechanism of Aconiti Lateralis Radix Praeparata (ALRP) and Zingiberis Rhizoma (ZR) on doxorubicin (DOX)-induced chronic heart failure (CHF) in rats by integrated approaches. METHODS: Effects of ALRP and ZR on cardiac function, serum biochemical indicators and histopathology in rats were analysed. Moreover, UHPLC-Q-TOF/MS was performed to identify the potential metabolites affecting the pathological process of CHF. Metabolomics and network pharmacology analyses were conducted to illustrate the possible pathways and network in CHF treatment. The predicted gene expression levels in heart tissue were verified and assessed by RT-PCR. KEY FINDINGS: ALRP-ZR demonstrated remarkable promotion of hemodynamic indices and alleviated histological damage of heart tissue. Metabolomics analyses showed that the therapeutic effect of ALRP and ZR is mainly associated with the regulation of eight metabolites and ten pathways, which may be responsible for the therapeutic efficacy of ALRP-ZR. Moreover, the results of RT-PCR showed that ALRP-ZR could substantially increase the expression level of energy metabolism-related genes, including PPARδ, PPARγ, Lpl, Scd, Fasn and Pla2g2e. CONCLUSIONS: The results highlighted the role of ALRP-ZR in the treatment of CHF by influencing the metabolites related to energy metabolism pathway via metabolomics and network pharmacology analyses.