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1.
Front Psychiatry ; 12: 695678, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594246

RESUMO

Background: Minimal research has examined utility of PC-PTSD-5 in family members of frontline medical workers. The aims of our study were to develop and elucidate the psychometric properties of the Chinese version of the PC-PTSD-5 and to determine its usefulness in screening for possible PTSD in relatives of Chinese healthcare workers during the COVID-19. Methods: We conducted a cross-sectional research in the relatives of medical staffs working in a general hospital during the COVID-19. Descriptive analysis was used to characterize demographic information of family members to find factors associated with PTSD symptoms. For reliability test, the internal consistency of PC-PTSD-5 was accessed using Cronbach's alpha coefficient. A validity test was assessed by Pearson's correlation between scales. A receiver operating characteristic (ROC) curve was used to evaluate the optimal cutoff score with the maximum Youden Index in this study. Results: The result of demographic information indicated that gender and the type of work undertaken by medical staff in the family have a potential impact on the PTSD symptoms of medical staff's family members. Cronbach's alpha coefficient of PC-PTSD-5 was 0.83, indicating the high reliability. Good validity was also demonstrated by Pearson coefficient. By calculating the Youden index, a cutoff score of 2 was found to be optimal in our study, with sensitivity of 80.74% and specificity of 88.43%. Conclusions: Our study has demonstrated the robust psychometric strengths of the PC-PTSD-5, introducing a reliable tool for screening PTSD among vulnerable and neglected families of these medical workers.

2.
Nat Commun ; 12(1): 5768, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599179

RESUMO

Selective separation of propyne/propadiene mixture to obtain pure propadiene (allene), an essential feedstock for organic synthesis, remains an unsolved challenge in the petrochemical industry, thanks mainly to their similar physicochemical properties. We herein introduce a convenient and energy-efficient physisorptive approach to achieve propyne/propadiene separation using microporous metal-organic frameworks (MOFs). Specifically, HKUST-1, one of the most widely studied high surface area MOFs that is available commercially, is found to exhibit benchmark performance (propadiene production up to 69.6 cm3/g, purity > 99.5%) as verified by dynamic breakthrough experiments. Experimental and modeling studies provide insight into the performance of HKUST-1 and indicate that it can be attributed to a synergy between thermodynamics and kinetics that arises from abundant open metal sites and cage-based molecular traps in HKUST-1.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34639480

RESUMO

Urban green spaces (UGSs) provide numerous irreplaceable environmental and social benefits to humankind, but the lack of baseline information makes it difficult to propose a reasonable greening strategy so as to achieve an equitable allocation of community green spaces. This paper divides UGSs into three classes using the spatial design network analysis (sDNA) and quantifies the UGS accessibility of communities in central Wuhan. Based on these results and the Gini coefficient, we analyze the UGS equity of the spatial distribution at the community level, then propose future greening strategies both at the city and community levels. The results show that the railway station and old Wuhan city are the core areas of traffic network strength (TNS). UGSs are evenly distributed in the core areas of TNS, but the number of UGSs in non-core areas is small, and their distribution is relatively uneven, and the number of communities with medium UGS accessibility is the largest, carrying the densest residential population. Most communities perform well in terms of UGS equity, but the UGS equity of 163 communities, covering a population of more than one million, remains to be improved. The method and conclusions of this study will contribute to the future greening policy making of 965 communities in central Wuhan, thus promoting the orderly planning and high-quality construction of community living circles.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21265032

RESUMO

SARS-CoV-2 infection causes most cases of severe illness and fatality in older age groups. In China, over 85% of individuals aged [>=]12 years have been vaccinated against COVID-19 (albeit with vaccines developed against historical lineages), while children aged 0-11 years are currently not eligible for vaccination (as of September 2021). The aim of this work is to assess whether the importation of Delta variant infections will shift the COVID-19 burden from adults to children. We developed an age-structured susceptible-infectious-removed model of SARS-CoV-2 transmission dynamics to simulate the epidemics triggered by the importation of Delta variant infections and project the age-specific incidence of SARS-CoV-2 infections, cases, hospitalisations, intensive care unit (ICU) admissions, and deaths. In the context of the vaccination programme targeting individuals aged [≥]12 years (as of September 2021), and in the absence of non-pharmaceutical interventions, the importation of Delta variant infections could lead to widespread transmission and substantial disease burden in mainland China, even with vaccination coverage as high as 97% across the currently eligible age groups. The symptomatic SARS-CoV-2 infections and hospitalisation are projected to shift towards children and young adolescents, with 13% of symptomatic infections and 30% of hospitalisations occurring in those aged 0-11 years. Extending the vaccination roll-out to include children aged 3-11 years is estimated to dramatically decrease the burden of symptomatic infections and hospitalisations within this age group (54% and 81%, respectively), but would have a low impact on protecting infants (aged 0-2 years). Our findings highlight the need to strengthen vaccination efforts by simultaneously extending the target population and elevating vaccine effectiveness. Author summaryOlder age groups have the highest risk of severe illness and fatality from SARS-CoV-2 infection. While the vaccination coverage in China is highly skewed towards older age groups. No study has quantified to what extent the spread of Delta variant infections and lack of vaccination in younger age groups will shift the COVID-19 burden towards younger age groups and how this will affect the return to normal. To this end, we developed an age-structured transmission model to mimic the epidemics triggered by imported Delta variant infections in China. In the context of the vaccination programme targeting individuals aged [≥]12 years as of September 2021, and in the absence of non-pharmaceutical interventions, the importation of Delta variant infections would lead to substantial disease burden, which will shift towards the 0-11-year age group. Extending the vaccination to children aged 3-11 years, for whom the currently available vaccines have been licensed, is projected to dramatically decrease symptomatic infections and hospitalisations within this age group but would have a low impact in protecting infants aged 0-2 years. This study highlights the value of extending vaccination to children aged 3-11 years and protecting infants 0-2 years by vaccinating their contacts.

5.
J Org Chem ; 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641679

RESUMO

A desymmetrization-based approach for the synthesis of piperidinyl acetic acid γ-secretase modulators has been developed. The synthetic sequence features the use of N-tert-butanesulfinyl imine reduction and a diastereoselective lactam formation to set up the chiral centers. The synthetic utility is demonstrated by the concise asymmetric synthesis of γ-secretase modulator GSM-1.

6.
Chemistry ; 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34608690

RESUMO

Entacapone (ENT) is a powerful catechol- O -methyl transferase inhibitor that is used for the diagnosis and treatment of Parkinson's syndrome, but the amount used must be well controlled to avoid overtreatment and side effect. Fast and selective detection of ENT needs well-matched energy levels and well-designed sensor-ENT interaction which is highly challenging. In this work, a water stable europium-based metal-organic framework ( Eu-TDA ) was synthesized to detect ENT by luminescence with excellent reusability and selectivity in the presence of main coexisting and interference species of plasma with a limit of detection of 5.01 µM. The experimental results showed that the luminescence of Eu-TDA can be effectively quenched by ENT via well-designed photoinduced electron transfer mechanism and internal filtration effect mechanism in the system.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34682720

RESUMO

The increasing amount of waste in cities poses a great challenge for sustainable development. Promoting waste sorting is one of the priorities for various levels of public authorities in the context of the rapid growth of waste generation all around China. To achieve this goal, waste-sorting policies should be precisely designed to ensure successful waste reduction at all stages. Previous studies have neglected the spillover effects of different regulatory policies, which may affect the overall goal of reducing waste by influencing different waste production stages. This paper fills this gap by comparing the spillover effects of two typical waste-sorting policies on sustainable consumption behaviours through a survey conducted in Shanghai and Beijing (control group). By combining quasi-natural experiment and questionnaire methods, this paper analyses data through a mediation test to explore the spillover effects between different regulatory policy groups and the effects of the mediation psychological factors. Results show that a penalty policy significantly decreases people's sustainable consumption behaviours through a negative spillover effect, while a voluntary participation policy significantly increases sustainable consumption behaviours through a positive spillover effect. Results can provide implications for policymaking in waste management and other pro-environmental fields to help cities become more sustainable by shifting multiple behaviours.

8.
Fitoterapia ; 155: 105054, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34626737

RESUMO

ß-Carboline alkaloid harmaline (HA) is a candidate drug molecule that has been proven to have broad and significant biological activity. Herein, the effects of HA on the riboflavin (RF)-sensitized photooxidation under aerobic conditions were studied for the first time. The photooxidation reaction of HA catalyzed by RF is triggered by UV light at 365 nm and shows a time-dependent stepwise reaction process. Seven transformed products, including five undescribed compounds, oxoharmalines A-E (1-4 and 7), and two known compounds, N-(2-(6-Methoxy-2-oxoindolin-3-yl)ethyl)acetamide (5) and harmine (6), were isolated and identified from the reaction system, following as the gradual oxidation mechanisms. The rare polymerization and dehydrogenation processes in radical-mediated photocatalytic reactions were involved in the process. The transformed products 2-7 exhibited significant neuroprotective activity in a model of H2O2-introduced injury in SH-SY5Y cells, which suggested that the products of the interaction between HA and vitamins may be beneficial to health.

9.
Phytochemistry ; 193: 112974, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34653908

RESUMO

Intestinal commensal fungi are vital to human health, and their metabolites play a key role in the reciprocal relationship. In the present work, eighteen alkaloids and seven monoterpenoids were isolated from the fermentation of the human intestinal fungus Penicillium oxalicum SL2, including seven undescribed alkaloids (penicilloxalines A-G), three undescribed monoterpenoids (penicilloxalines H-J), and fifteen reported compounds. The structures of the isolated compounds were identified by HRESIMS, 1D and 2D NMR, electronic circular dichroism spectra and quantum chemical calculations. Some metabolites displayed moderate agonistic effects against the pregnane X receptor (PXR), whereas (6R)3,7-dimethyl-6,7-dihydroxy-2(Z)-octenoic acid displayed a significant agonistic effect against the farnesoid X receptor (FXR) with an EC50 value of 0.43 µM, which was verified by investigating FXR downstream target genes and proteins, such as small heterodimer partner 1 (SHP1), fibroblast growth factor (FGF), and bile salt export pump (BSEP).

10.
IEEE Trans Cybern ; PP2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587111

RESUMO

In this article, the problem of the asynchronous fault detection (FD) observer design is discussed for 2-D Markov jump systems (MJSs) expressed by a Roesser model. In general, the FD observer cannot work synchronously with the system, that is, the mode of the observer varies with the mode of the system in line with some conditional transitional probabilities. For dealing with this difficult point, a hidden Markov model (HMM) is employed. Then, combining the attenuation index and H increscent index, a multiobjective solution to the FD problem is formed. In terms of linear matrix inequality technology, sufficient conditions are gained to guarantee the existence of the asynchronous FD. Simultaneously, an asynchronous FD algorithm is generated to acquire the optimal performance indices. Finally, a numerical example concerned with the Darboux equation is demonstrated to exhibit the soundness of the developed approach.

11.
Micron ; 150: 103147, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34534920

RESUMO

The wide application of multi-frequency atomic force microscopy (AFM) places higher demands on the higher-order modes response of the cantilever. The response of the higher modes however is generally weaker than that of the fundamental mode in air. Researchers have proposed many methods, most of which involve cantilever modification, to enhance higher-order eigenmodes response. These previous results are proved to be effective, but the microfabrication is expensive. In this article, we propose a novel model based on bridge/cantilever coupled system to enhance the higher-order modes response of AFM cantilever. The segmented beam model provides a new thinking to explain the appearance of undesired peaks in mode analysis of cantilever. Through theoretical analysis and simulation, we find that higher resonance modes are enhanced by tuning the bridge to match the high resonances of the single clamped cantilever. The length, thickness of the coupled system and the location of excitation can affect the enhancement. In summary, this model provides a new way to improve higher mode response for multi-frequency and other high bandwidth applications of AFM.

12.
Dalton Trans ; 50(37): 13124-13137, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581367

RESUMO

Photo-induced variation of magnetism from ligand-based electron transfer has been extensively studied because of its potential applications in magneto-optical memory devices, light-responsive switches, and high-density information storage materials. In this review, we discussed the progress in the photo-induced variation of magnetism in coordination polymers with ligand-to-metal charge transfer (LMCT), ligand-to-ligand charge transfer (LLCT) and internal ligand charge transfer (ILCT), which provides fundamentals for the rational design of multi-functional materials. We also discussed the design and synthetic strategy of such molecule-based materials and gave views on the current challenges and growth trends in this field.

13.
Front Cell Dev Biol ; 9: 626045, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568308

RESUMO

The role of gut microbiota in the development of various tumors has been a rising topic of public interest, and in recent years, many studies have reported a close relationship between microbial groups and tumor development. Gut microbiota play a role in host metabolism, and the positive and negative alterations of these microbiota have an effect on tumor treatment. The microbiota directly promote, eliminate, and coordinate the efficacy of chemotherapy drugs and the toxicity of adjuvant drugs, and enhance the ability of patients to respond to tumors in adjuvant immunotherapy. In this review, we outline the significance of gut microbiota in tumor development, reveal its impacts on chemotherapy and immunotherapy, and discover various potential mechanisms whereby they influence tumor treatment. This review demonstrates the importance of intestinal microbiota-related research for clinical tumor treatment and provides additional strategy for clinical assistance in cancer treatment.

15.
Virus Res ; 305: 198553, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34487767

RESUMO

COVID-19 is seriously threatening human health all over the world. A comprehensive understanding of the genetic mechanisms driving the rapid evolution of its pathogen (SARS-CoV-2) is the key to controlling this pandemic. In this study, by comparing the entire genome sequences of SARS-CoV-2 isolates from Asia, Europe and America, and analyzing their phylogenetic histories, we found a lineage derived from a recombination event that likely occurred before March 2020. More importantly, the recombinant offspring has become the dominant strain responsible for more than one-third of the global cases in the pandemic. These results indicated that the recombination might have played a key role in the pandemic of the virus.


Assuntos
COVID-19/epidemiologia , Evolução Molecular , Genoma Viral , Recombinação Homóloga , Mosaicismo , SARS-CoV-2/genética , América/epidemiologia , Ásia/epidemiologia , Sequência de Bases , COVID-19/história , COVID-19/transmissão , COVID-19/virologia , Europa (Continente)/epidemiologia , Genômica/métodos , História do Século XXI , Humanos , Mutação , Filogenia , SARS-CoV-2/classificação , SARS-CoV-2/patogenicidade
16.
Bioorg Chem ; 116: 105356, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34560562

RESUMO

Two undescribed ent-abietane-type diterpenoid dimers with nonacyclic backbone formed by intermolecular [4 + 2] cycloaddition into a spirocyclic skeleton, bisfischoids A (1) and B (2), along with a known one fischdiabietane A (3), were identified from Euphorbia fischeriana Steud. Their structures were elucidated by extensive spectroscopic analysis, ECD and NMR calculation combined with DP4+ probability analysis, as well as X-ray diffraction. The anti-inflammatory potential of dimers 1-3 were examined using their inhibitory effects on soluble epoxide hydrolase (sEH), which revealed that 1 and 2 exhibited promising activities with inhibition constant (Ki) of 3.20 and 1.95 µM, respectively. Further studies of molecular docking and molecular dynamics indicated that amino acid residue Tyr343 in the catalytic cavity of sEH was the key site for their inhibitory function.

17.
Org Lett ; 23(20): 7865-7872, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34582193

RESUMO

A palladium-catalyzed enantioselective Heck cyclization/dearomatization cascade via capturing the cyclized Heck π-allylpalladium intermediate by ß-naphthols is reported, which provides a new strategy for the construction of chiral indole-terpenoid frameworks. This method affords indole-functionalized ß-naphthalenone compounds bearing an all-carbon-substituted quaternary chiral center in excellent yields (up to 92%) and enantioselectivities (up to 94% ee). In addition, the utility of this method is showcased by the gram-scale syntheses and diverse transformations of the dearomatized products.

18.
Am J Transl Res ; 13(8): 8977-8987, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540009

RESUMO

OBJECTIVE: To explore the effects of early comprehensive and specific behavioral interventions on improving social communication and attenuating anxiety in autism patients. METHODS: This study was based on the modular comprehensive analysis method and explored the neurotransmitter conduction mechanism in the pathogenesis of autism. We downloaded autism-related data from the Gene Expression Omnibus (GEO) database and performed a differential analysis, a co-expression Network Analysis (WGCNA) analysis, a GO function, and a KEGG pathway enrichment analysis. Finally, we predicted the non-coding RNAs (ncRNAs) and transcription factors (TFs) that regulate the module on the basis of hypergeometric testing. RESULTS: We obtained five co-expression modules, in which the active regulatory effects of the MTA3, PHB2, TNXB, DCTN2, and RBM23 genes in the dysfunction modules were obtained. The module genes were predominantly involved in biological processes and significantly regulated the mRNA monitoring and calcium signaling pathways. In addition, we identified a prominent regulation effect of the ncRNA and TF pivots on the dysfunction modules. CONCLUSIONS: This study deciphered a comprehensive network of key genes involved in autism, and it reveals the main dysfunction modules, the latent regulatory factors, and the driver genes for autism, contributing to our further understanding of the mechanisms of autism neuronal conduction disorders.

19.
Sci Total Environ ; 805: 150240, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34536869

RESUMO

Good knowledge on the stable carbon isotopic composition (δ13C) of fossil fuels is critical for the estimation of atmospheric CO2 sources. Here, we complied a comprehensive δ13C database including 336 coal, 580 oil, and 1160 natural gas data based on the extensive literature search, and conducted field measurements in two megacities, to characterize the δ13C signatures of Chinese fossil fuels. Results show that coal exhibits a narrow range and the most enriched in δ13C signature, oil displays intermediate variations both in the distribution and value of δ13C. By contrast, natural gas is strongly depleted but became more enriched in δ13C signature due to the shift in production from isotopically light oil-type gas to isotopically heavy coal-type gas. We found an obvious overlap between the δ13C distributions of oil and natural gas, and the carbon isotopic difference between oil and natural gas is minimized in Ordos Basin. Therefore, we suggested that the geographic origin is a certain factor that must be considered when δ13C of fossil fuels is used to estimate CO2 source contributions, and the measurement of δ13CO2 signatures of local end members is a better alternative in the absence of detailed information about the geographical origins of fossil fuels. This work is helpful in improving the ability to quantify CO2 sources of fossil fuel emissions in China, and also make a contribute to the global carbon isotope database.

20.
Eur Phys J C Part Fields ; 81(9): 789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512143

RESUMO

We clarify the problem in which occasions can gravitational force be regarded emergent from thermodynamics, by proposing an entropic mechanism that can extract the entropic gradient existing in spacetime, due to the variation of the Casini-Bekenstein bound in specific quasi-static processes with the heat flux δ Q into the whole casual wedge. We explicitly formulate the derivation of inertial force as the emergent gravitational attraction from the Entanglement First Law. We find the saturation of the bound along with the vanishing relative entropy corresponds to the variation of minimal surface. To covariant meaning, it is the Bousso bound. Besides, this understanding is connected to recent Pennington's work on Black Hole Information Paradox, suggesting a Page-Curve function origins from removing attraction by the external heat bath. Our theory from entanglement now overcomes several criticism towards Verlinde's original entropic force proposal, and is able to co-exist with Susskind's Complexity Tendency. This entropic mechanism reproduces the Newton's Second Law in Rindler space and the gravitational force (together with derivation of the Einstein equation) beyond the near-horizon region, and can be adapted into AdS/CFT and other generic situations.

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