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1.
Front Cardiovasc Med ; 9: 940615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093170

RESUMO

Korotkoff sounds (K-sounds) have been around for over 100 years and are considered the gold standard for blood pressure (BP) measurement. K-sounds are also unique for the diagnosis and treatment of cardiovascular diseases; however, their efficacy is limited. The incidences of heart failure (HF) are increasing, which necessitate the development of a rapid and convenient pre-hospital screening method. In this review, we propose a deep learning (DL) method and the possibility of using K-methods to predict cardiac function changes for the detection of cardiac dysfunctions.

2.
Carbohydr Polym ; 296: 119975, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36088013

RESUMO

The temperature-sensitive hydrogel (H/D) composed of hydroxybutyl chitosan (HBC) and diatom biosilica (DB) was prepared by physically mixing HBC solution with DB at low temperature. The rheological measurements confirmed that the incorporation of DB to hydroxybutyl chitosan could significantly enhance the mechanical strength of the hydrogels without disrupting its reversible phase transition behavior. The hierarchical porous structure of DB and its rich negatively charged surface provided penetration anchor points for HBC molecular chains, which significantly enhanced the mechanical properties of H/D. The gelation temperature, gelation time and mechanical strength could be easily regulated by change of the ratio of DB in composite hydrogel. The maximum storage modulus of HBC hydrogel was increased to 17 times after adding DB. H/D exhibited favorable blood compatibility (hemolysis rate < 5 %) and no cytotoxicity to L929 cells which are promising for the applications as tissue regeneration materials and wound dressing in biomedical fields.


Assuntos
Quitosana , Diatomáceas , Quitosana/análogos & derivados , Quitosana/química , Hidrogéis/química , Hidrogéis/farmacologia , Temperatura
3.
Ultrason Sonochem ; 89: 106143, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36058140

RESUMO

The effect of compressive stress on cavitation erosion-corrosion behavior of nickel-aluminum bronze alloy was investigated, and the results showed that the alloy exhibited selective phase corrosion of eutectoid "α + κiii" and its destruction was aggravated with more cavitation mass loss up to 1.74 times of the specimen without stress. It was mainly owing to the enhanced corrosion-induced erosion caused by compressive stress, which led to lattice distortion of the alloy and the resulting accelerated selective phase corrosion with increasing surface roughness, and then intensified the synergistic effect of electrochemical corrosion and mechanical erosion.

4.
Sensors (Basel) ; 22(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36146257

RESUMO

This technical note proposes a clapping vibration energy harvesting system (CVEH system) installed in a rotating system. This device includes a rotating wheel, a drive shaft that rotates the wheel, and a double elastic steel sheet fixed on the drive shaft. One of the free ends of the steel is fixed with a magnet, and the free end of the other elastic steel is fixed with a PZT patch. We also install an array of magnets on the periphery (rim) of the wheel. The rim magnets repulse the magnet on the elastic steel sheet of the transmission shaft, causing the elastic steel to oscillate periodically, and slap the piezoelectric patch installed on the other elastic steel sheet to generate electricity. In this study, the authors' previous study on the voltage output was improved, and the accurate nonlinear natural frequency of the elastic steel was obtained by the dimensional analysis method. By adjusting the rotation speed of the wheel, the precise frequency was controlled to accurately excite the energy harvesting system and obtain the best output voltage. A simple experiment was also performed to correlate with the theoretical model. The voltage and power output efficiencies of the nonlinear frequency to linear frequency excitation of the CVEH system can reach 15.7% and 33.5%, respectively. This study confirms that the clapping VEH system has practical power generation benefits, and verifies that nonlinear frequencies are more effective than linear frequencies to excite the CVEH system to generate electricity.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36078323

RESUMO

A community is the basic unit of a city. Scientific and effective evaluations of the construction effect of safe communities can improve the construction capacity of community disaster prevention and mitigation; it is also the basis for improving urban public safety and realizing stable and sustainable urban operation. First, following the development framework of a safe community and taking two typical communities in Xi'an, China, as examples, based on the literature and expert opinions, the initial indicators of a safe community are determined. Second, based on existing data, the literature and expert opinions, a questionnaire is designed, and the reliability and validity of the questionnaire are tested by exploratory factor analysis. Third, the indicators for evaluating the construction ability of a safe community are selected. Finally, an evaluation model of the construction ability of safe communities is constructed by using the comprehensive weighting technique for order of preference by similarity to the ideal solution (TOPSIS), which is applied to the actual evaluation of eighteen representative communities in Xi'an. The main findings are as follows. (1) The sense of community security is the collective consciousness of community residents. It includes not only the security and feelings of community residents themselves, but also the cognition of the impact of social policies at the macro and micro-levels on community residents, their families, and even the whole community. (2) From the three levels of consciousness, technology, and policy as the starting points for the construction of the theoretical model of a safe community, organizational resilience, accessibility resilience, social environmental resilience, and capital resilience are found to be the main influencing factors in the construction of a safe community. (3) Using questionnaires and expert interviews to preliminarily screen evaluation indicators and using the comprehensive weighting TOPSIS method to build an evaluation model can effectively avoid the defects of traditional empirical research on the validity and reliability of methods. (4) The ranking of the eighteen representative communities in the empirical analysis is basically consistent with the selection results of the national comprehensive disaster reduction demonstration community, which indicates the effectiveness and accuracy of the indicators and algorithms.


Assuntos
Política Pública , China , Cidades , Análise Fatorial , Humanos , Reprodutibilidade dos Testes
6.
Artigo em Inglês | MEDLINE | ID: mdl-36078791

RESUMO

Mitigating climate change requires long-term global efforts. The aim of this study is to simulate the possible paths of CO2 emissions in G20 countries and the world from 2020 to 2050, by using the STIRPAT model and SSP scenarios with different constraints (SSP baseline, SSP-3.4). The results show that: (1) the world's CO2 emissions cannot peak in the SSP baseline scenarios, but can peak in the SSP-3.4 scenarios through four paths other than the high fossil energy consumption path; (2) for G20 countries, in the SSP baseline scenarios, 13 countries such as China, the United States, and the United Kingdom can achieve the peak, while six countries such as Argentina, India, and Saudi Arabia cannot. In the SSP-3.4 scenarios, Saudi Arabia cannot achieve the peak, while other countries can achieve the peak, and most of them are likely to achieve significant CO2 emission reductions by 2050; (3) climate goals have a crowding-out effect on other sustainable development goals, with less impact on developed countries and a greater impact on developing countries; and (4) the optimization of the energy structure and a low energy intensity can greatly advance the peak time of CO2 emissions.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Dióxido de Carbono/análise , China , Mudança Climática , Fatores Socioeconômicos
7.
Colloids Surf B Biointerfaces ; 219: 112809, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36067680

RESUMO

The development of fast, safe and effective hemostatic materials is crucial for pre-hospital first aid. In this study, diatomite hemostatic granules (Dhp) were developed by rotating granulation method using silica sol as binder. During rotating granulation process, the Pre-Dhp were prepared by rolling snowball effect, in which nano-silica in silica sol uniformly distributed on the surface of diatomite and polymerized through hydrogen bond to produce strong adhesion. After high-temperature calcination, the hydrogen bond transformed to silica oxygen bond and the three-dimensional gel network formed by silica sol was destroyed to exposed the pores of diatomite. Dhp retained the porous structure of diatomite with hierarchical porous structure (from nano to micro scale). Dhp could quickly adsorb the tangible components in the blood, exhibited rapid hemostatic ability (clotting time was shortened by 43 % than that of control group), and good biocompatibility (hemolysis rate < 7 %, no cytotoxicity). Dhp residue was not found in the wound of rat tail amputation model, indicating that the adhesion of silica sol and high-temperature curing treatment enhanced the stability of Dhp and reduced the hidden danger of micro thrombosis caused by residual substances entering blood vessels. Our study proved that Dhp prepared by silica sol bonding and rotary granulation was excellent hemostatic material with non-toxic side effects and rapid coagulation promotion.

8.
Foods ; 11(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36140925

RESUMO

The pH values of sausages stuffed in natural hog casings with different modifications (soy lecithin, soy oil, orange extracts (OE) from waste orange peels, lactic acid in slush salt, and treatment time) after 16-day 4 °C storage were evaluated for the first time by hyperspectral imaging (350-1100 nm) coupled with response surface methodology (RSM). A partial least squares regression (PLSR) model was developed to relate the spectra to the pH of sausages. Spectral pretreatment, including first derivative, second derivative, multiplicative scatter correction (MSC), standard normal variate (SNV), normalization, and normalization, with different combinations was employed to improve model performance. RSM showed that only soy lecithin and OE interactively affected the pH of sausages (p < 0.05). The pH value decreased when the casing was treated with a higher concentration of soy lecithin with 0.26% OE. As the first and second derivatives are commonly used to eliminate the baseline shift, the PLSR model derived from absorbance pretreated by the first derivative in the full wavelengths showed a calibration coefficient of determination (R2) of 0.73 with a root mean square error of calibration of 0.4283. Twelve feature wavelengths were selected with a comparable R2 value compared with the full wavelengths. The prediction map enables the visualization of the pH evolution of sausages stuffed in the modified casings added with OE.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36169831

RESUMO

The exponential random graph model (ERGM) is an effective approach for testing the dynamic and local processes of a network. This paper explores the structure of stakeholders' partnerships in a tourism waste management network using high-order dependency ERGMs based on relational data obtained from a field survey in Motuo County, China. The results reveal that (1) the network has many edges, indicating a tight network; (2) the geometrically weighted edge distribution shows a high transitive effect of the network; (3) the structural effect is more significant than the attribute effect; (4) there is a good agreement between the simulation results and observations, suggesting a tourism waste network with close connections and collaborative division of labor. These findings indicate that different groups of stakeholders have been extensively involved in tourism waste management in Motuo County. The edgewise shared partners formed by stakeholders of different groups increase the information transmission efficiency of the network. The results have implications for tourism waste management, specifically for promoting sustainability transitions via network governance.

10.
Front Public Health ; 10: 963620, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983362

RESUMO

The COVID-19 outbreak has greatly impacted the stability of the global financial markets. In the post-COVID-19 pandemic era, the risk contagion patterns of the global financial markets may change. This paper utilizes the conditional value-at-risk (ΔCoVaR) model to measure the risk level of the financial markets in various economies and uses the TVP-VAR-CONNECTEDNESS approach to construct a time-varying spillover index. Based on the dimensions of time and space, we explored the contagion path, contagion status, and contagion structure characteristics of global financial market risk before and during the COVID-19 pandemic. The results entail several conclusions. (i) The COVID-19 pandemic increased the spillover level of global financial market risk and the risk connectedness of financial markets in different countries. In addition, during the concentrated outbreak period of COVID-19, the risk spillover level in developing countries rose rapidly, while the financial risk spillover level in developed countries decreased significantly. (ii) The impact of the COVID-19 pandemic on the spillover of the global financial market risk is time-varying, and there is a strong correlation between the risk spillover level of the financial markets of the world and the severity of the COVID-19 pandemic. (iii) Due to the impact of the COVID-19 pandemic, Brazil, Canada, and Russia have become new risk spillover centers; in the post-COVID-19 pandemic era, China's spillover to developed countries has increased, and the financial influence of China has also gradually increased. In addition, the risk contagion capacity of financial markets among European countries is gradually converging. (iv) During the concentrated outbreak of the COVID-19 pandemic, the Americas were the main exporter of global financial market risk, while Europe played a role in risk absorption.


Assuntos
COVID-19 , Brasil , COVID-19/epidemiologia , China/epidemiologia , Europa (Continente)/epidemiologia , Humanos , Pandemias , Estados Unidos
11.
Mol Genet Genomic Med ; : e2025, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35985664

RESUMO

BACKGROUND: Recent research found that biallelic HPDL variants can cause neurodevelopmental disorder with progressive spasticity and brain white matter abnormalities (NEDSWMA), with only a few reports. Clinical phenotypic information on individuals with damaging HPDL variants may also be incomplete. The phenotype of NEDSWMA is characterized by severe neurodevelopmental delay, brain atrophy, and spasticity in infancy. METHODS: Exome sequencing was used in the proband and his parents to identify the underlying genetic cause. Candidate mutations were validated by classic Sanger sequencing. The clinical presentation of the infant who carried HPDL variants was summarized. RESULTS: We identified a novel compound heterozygous variants in HPDL, c.995delC (p.T332Mfs) and c.1051C>T (p.Q351*) in the patient a 6-month-old boy presenting with global developmental delay, seizures, hypertonia, and limb spasticity. Brain magnetic resonance imaging (MRI) showed thin corpus callosum, ventriculomegaly, white matter volume reduction, bilateral frontotemporal subarachnoid widening, and sulcus deeping. CONCLUSION: Our results provided important information for the associations of variants in HPDL with the neurodevelopmental disorder in infants, and broaden the genetic spectrum of HPDL-related disease. This is the second report of the HPDL mutation causing infant neurodevelopmental disorders in a Chinese population.

12.
Clinics (Sao Paulo) ; 77: 100095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36027756

RESUMO

OBJECTIVES: Depression is common after both lacunar stroke and non-lacunar stroke and might be associated with lesion locations as proven by some studies. This study aimed to identify whether lesion location was critical for depression after both lacunar and non-lacunar strokes. METHODS: A cohort of ischemic stroke patients was assigned to either a lacunar stroke group or a non-lacunar stroke group after a brain MRI scan. Neurological deficits and treatment response was evaluated during hospitalization. The occurrence of depression was evaluated 3 months later. Logistic regressions were used to identify the independent risk factors for depression after lacunar and non-lacunar stroke respectively. RESULTS: 83 of 246 patients with lacunar stroke and 71 of 185 patients with non-lacunar stroke developed depression. Infarctions in the frontal cortex, severe neurological deficits, and a high degree of handicap were identified as the independent risk factors for depression after non-lacunar stroke, while lesion location was not associated with depression after lacunar stroke. CONCLUSION: The main determinants for depression after lacunar and non-lacunar stroke were different. Lesion location was critical only for depression after non-lacunar stroke.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral Lacunar , Acidente Vascular Cerebral , Estudos de Coortes , Depressão , Humanos , Fatores de Risco
13.
Artigo em Inglês | MEDLINE | ID: mdl-35969342

RESUMO

Little research has been conducted on the multiple possible future environmental effects of different types of information and communication technology (ICT) investment. This paper innovatively calculates the ICT productive capital stock (PCS) in China from 2007 to 2018 and explores the multiple effects of ICT PCS on carbon emissions. The results show that (1) ICT PCS is conducive to carbon emission reduction; furthermore, ICT software PCS has a significant carbon emission reduction effect, while ICT hardware PCS has the opposite outcome. (2) The spatial effect demonstrates that ICT and its hardware and software PCS can significantly reduce carbon emissions in surrounding areas. (3) The ICT PCS indirectly affects carbon emissions through the digital economy and energy efficiency, but the role of the influence mechanism varies according to the type of ICT PCS. (4) There is a nonlinear relationship between all ICT PCS and carbon emissions due to differences in green productivity and ICT PCS levels. Finally, this study provides valuable references for optimizing ICT investment and promoting low-carbon development.

14.
Curr Psychol ; : 1-11, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35891892

RESUMO

During the COVID-19 pandemic, the mental health state of adolescents had caused widespread concern, especially the various problems caused by the relationship between adolescents and their parents in the long isolation at home. Based on the mindfulness reperceiving model and Rogers's Self-theory, this study aimed to explore the roles of adolescents' self-concept clarity and mindfulness level in the relationship between parental psychological control and adolescent depression. A total of 1,100 junior high school students from China completed the questionnaires regarding parental psychological control, depression, self-concept clarity, and mindfulness. Moderated mediation analyses suggest that parental psychological control affects adolescent depression via self-concept clarity. The association between parental psychological control and depression is moderated by self-concept clarity. The effect was stronger among adolescents with high mindfulness levels than those with low. This study suggests that it is necessary to consider both parental factors and adolescents' factors in the future. The interventions on self-concept or mindfulness may ameliorate adolescent mental problems more effectively.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35886116

RESUMO

Affordable and warm housing is a basic household living need, which is closely related to human health and well-being. This study attempts to establish the link between household housing conditions and energy poverty in China from the perspective of energy self-restriction using logit and mediation models based on microdata. The results report that: (1) households are more likely to be exposed to energy poverty if they live in larger, older, poorly insulated houses, without basic energy service equipment, and in rental housing; (2) the area of residence and energy installations are the main characteristics that distinguish energy poverty from non-energy poverty; (3) the link between housing conditions and energy poverty is reinforced by the psychology and behavior of households, with those living in poor conditions tending to restrain their energy consumption, thus worsening their energy poverty situation.


Assuntos
Qualidade Habitacional , Pobreza , China , Características da Família , Habitação , Humanos
16.
Materials (Basel) ; 15(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35888293

RESUMO

In this paper, cement based on fused silica powder @ polyurethane urea (FSP@PUU) with a micro constrained damping structure was studied. Firstly, FSP@PUU core-shell particles were prepared by heterogeneous stepwise addition polymerization method and added into cement paste as damping filler to form a micro-constrained damping structure inside cement paste. The mechanical property and damping performance of cement-based composites were characterized by compressive strength, dynamic mechanical analysis (DMA) test and modal vibration test. The results showed that the damping performance of FSP @ PUU cement-based composites was affected by temperature, and the loss tangent of cement with 6wt% FSP@PUU increased to about 0.057 at -35 °C to 35 °C, which was 1.5 times cement paste within the glass transition temperature. With 6 wt% FSP@PUU, the damping ratio of cement-based composites increased by 58% compared with cement paste in the frequency range of 175-300 Hz, while the compressive strength decreased by only 5%. The cement with suitable FSP@PUU possesses excellent damping performance.

17.
Front Microbiol ; 13: 898961, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903472

RESUMO

Phage therapy is an alternative approach to overcome the problem of multidrug resistance in bacteria. In this study, a bacteriophage named PZL-Ah152, which infects Aeromonas hydrophila, was isolated from sewage, and its biological characteristics and genome were studied. The genome contained 54 putative coding sequences and lacked known putative virulence factors, so it could be applied to phage therapy. Therefore, we performed a study to (i) investigate the efficacy of PZL-Ah152 in reducing the abundance of pathogenic A. hydrophila strain 152 in experimentally infected crucian carps, (ii) evaluate the safety of 12 consecutive days of intraperitoneal phage injection in crucian carps, and (iii) determine how bacteriophages impact the normal gut microbiota. The in vivo and in vitro results indicated that the phage could effectively eliminate A. hydrophila. Administering PZL-Ah152 (2 × 109 PFU) could effectively protect the fish (2 × 108 CFU/carp). Furthermore, a 12-day consecutive injection of PZL-Ah152 did not cause significant adverse effects in the main organs of the treated animals. We also found that members of the genus Aeromonas could enter and colonize the gut. The phage PZL-Ah152 reduced the number of colonies of the genus Aeromonas. However, no significant changes were observed in α-diversity and ß-diversity parameters, which suggested that the consumed phage had little effect on the gut microbiota. All the results illustrated that PZL-Ah152 could be a new therapeutic method for infections caused by A. hydrophila.

18.
Comput Intell Neurosci ; 2022: 4965908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795766

RESUMO

During the last two or three decades where innovations in technology have been dominant, especially the rapid development of electronic information technology, various types of electronic devices have been developed for different application areas. It is this technological-assisted equipment that has drastic effects on the lifestyle of every creature in general and human beings in particular. In addition to the other activities or services, technology has enabled human beings to write on electronic devices, which is due to the fact that these devices will generate electronic signature handwriting that is extremely useful for human beings. They may effectively cope with the electronization of traditional signature handwriting and ease the difficulties of authenticating the identification information of the signatory of electronic documents when used in conjunction with electronic documents. This method is frequently utilized in e-government, e-commerce, banking and insurance, medical care, and other industries. This study uses the current mainstream computer vision technology to compare and analyze the handwriting dynamic characteristics of electronic signature and conventional signature. It uses the electronic signature God and software to collect and extract the original characteristic data of user's electronic signature and then extracts the characteristics of average writing speed, duration, and average pressure on the basis of these data for analysis. Among these techniques, the writing time of electronic signature is longer than that of conventional signature, and the average speed of conventional signature notes is higher than that of electronic signature, and when analyzing the average pressure characteristics, the conventional signature pressure is greater than the electronic signature pressure.


Assuntos
Computadores , Software , Eletrônica , Escrita Manual , Humanos , Tecnologia
19.
J Org Chem ; 87(16): 11226-11230, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35901265

RESUMO

Herein, we report a strategically novel method for the efficient construction of indole skeletons using 2-phenylisoxazol-5-ones as the starting material. This reaction proceeds via Brønsted acid-promoted α-iminyl cation generation by N-O bond cleavage and a subsequent intramolecular cyclization to afford 1H-indole-3-carboxylic acid, which further undergoes decarboxylation to yield the final product. Control experiments show that N-O bond cleavage and intramolecular cyclization proceed so fast that the 1H-indole-3-carboxylic acid could be isolated in high yields even after 5-10 min. The substrate scope of this transformation is broad, and the desired products are obtained in moderate to good yields. The transition-metal-free reaction condition, CO2 as the sole byproduct, and good practicability add to the synthetic potential of this transformation in the pharmaceutical and flavor industries.


Assuntos
Androstenóis , Indóis , Ácidos/química , Cátions , Ciclização , Indóis/química
20.
Chem Sci ; 13(21): 6283-6290, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35733884

RESUMO

It is highly desirable to reduce the environmental pollution related to the disposal of end-of-life plastics. Polycarbonates derived from the copolymerization of CO2 and epoxides have attracted much attention since they can enable CO2-fixation and furnish biorenewable and degradable polymeric materials. So far, only linear CO2-based polycarbonates have been reported and typically degraded to cyclic carbonates. Here we synthesize a homogeneous dinuclear methyl zinc catalyst ((BDI-ZnMe)2, 1) to rapidly copolymerize meso-CHO and CO2 into poly(cyclohexene carbonate) (PCHC) with an unprecedentedly cyclic structure. Moreover, in the presence of trace amounts of water, a heterogeneous multi-nuclear zinc catalyst ((BDI-(ZnMe2·xH2O)) n , 2) is prepared and shows up to 99% selectivity towards the degradation of PCHC back to meso-CHO and CO2. This strategy not only achieves the first case of cyclic CO2-based polycarbonate but also realizes the complete chemical recycling of PCHC back to its monomers, representing closed-loop recycling of CO2-based polycarbonates.

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