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1.
Clin Transl Sci ; 16(11): 2299-2309, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775976

RESUMO

This study measured serum high mobility group box 1 (HMGB1) levels in patients with acute myocardial infarction (AMI) and/or heart failure (HF) and evaluated their relationship with peripheral inflammatory biomarkers and cardiac biomarkers, which have not been reported before. Of the patients, 55 had AMI without HF (AMI-HF ), 42 had AMI with HF (AMI+HF ), and 60 had HF without AMI (HF-AMI ) compared with 50 healthy controls. Blood samples were collected to assess serum HMGB1 levels and blood test-related inflammatory biomarkers (e.g., erythrocyte sedimentation rate [ESR], hs-CRP, uric acid, and white blood cell count) and cardiac biomarkers (e.g., MYO, cTnI, CKMB, CK, NT-proBNP, LDH, aspartate aminotransferase [AST], and alanine aminotransferase [ALT]). Compared to healthy controls, three groups of patients, especially those with AMI+HF , had significantly higher levels of serum HMGB1. All tested inflammatory biomarkers (except uric acid) were significantly positively correlated with HMGB1 in patients with AMI patients but not in patients with non-AMI. In addition, all tested cardiac biomarkers (except NT-proBNP in AMI-HF ) were significantly higher in patients with AMI than in control individuals. The levels of MYO, cTnI, CKMB, CK, AST, and ALT were not significantly changed in patients with HF-AMI compared to control individuals, but were still much lower than those in patients with AMI (except ALT). In all patients, the levels of NT-proBNP, and cTnI were significantly correlated with HMGB1 levels. Except for MYO, LDH, AST, and ALT, all cardiac biomarkers in AMI-HF and AMI+HF showed a significant correlation with HMGB1. Among risk factors, hypertension, diabetes, previous heart disease, and reduced left ventricular ejection fraction showed a significant correlation with HMGB1 in all disease groups.


Assuntos
Proteína HMGB1 , Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Biomarcadores , Insuficiência Cardíaca/diagnóstico , Infarto do Miocárdio/diagnóstico , Volume Sistólico , Ácido Úrico , Função Ventricular Esquerda
2.
Int J Hypertens ; 2023: 9497716, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521117

RESUMO

It has been shown that miR-145 is involved in the differentiation of vascular smooth muscle cells (VSMCs) and may regulate vascular remodeling. However, the molecular mechanisms behind these pathological processes in hypertension are not fully elucidated. The present study was to examine whether miR-145 modulates phenotypic transformation of VSMCs under normal state and synthetic state and to explore the possible role of ADAM17-mediated ACE2 shedding and ACE2-Ang-(1-7)-Mas receptor axis. Wistar rats were fed with high-sucrose/high-fat diet for 30 weeks to establish a metabolic hypertension animal model. VSMCs were cultured and treated with Ang II with or without miR-145 mimics or miR-145 inhibitor. Results showed the expression of contractile markers α-SMA and SM22α, miR-145, ACE2, and Mas receptor reduced in the thoracic aorta of metabolic hypertensive rats (MHRs), while that of synthetic marker OPN increased as compared to the control group. In in vitro study, miR-145 inhibitor inhibited the expression of α-SMA, SM22α, ACE2, Mas receptor, and the Ang-(1-7) excretion and induced the expression of synthetic markers OPN, EREG, and MMP2. However, miR-145 mimic produced opposite effects on the VSMCs. In addition, in the synthetic VSMC induced by Ang II, miR-145 inhibitor partially reversed the induced expression of OPN, EREG, and MMP2 by Ang II, while further decreasing the expression of α-SMA and SM22α and ACE2-Ang-(1-7)-Mas receptor. Cotreatment with ADAM17 siRNA partially reversed the inducible effect of miR-145 inhibitor on the EREG and MMP2, induced Ang-(1-7) excretion, and upregulated ACE2 and Mas receptor expression. In conclusion, miR-145 alleviates phenotype transition from contractile to synthetic type via ADAM17-mediated ACE2 shedding in VSMCs and retains the activation of ACE2-Ang-(1-7)-Mas axis, which may benefit the vascular structural remodeling in the metabolic hypertension.

3.
Ultraschall Med ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37402406

RESUMO

PURPOSE: To collect validity evidence for a simulator-based obstetric ultrasound competency assessment tool (OUCAT). METHODS: 89 sonographers from three centers (XY, MC, DT), including novices (n=21), experienced trainees (n=44), and experts (n=24), participated in the competency assessment. Validity evidence of OUCAT was collected according to Standards for Educational and Psychological Testing. Content validity was ensured by reviewing guidelines and reaching expert consensus. The response process was ensured via training raters. Internal structure was explored through internal consistency, inter-rater reliability, and test-retest reliability. Relations to other variables were explored by comparing OUCAT scores of sonographers with different experience. Evidence for consequences was collected by determining the pass/fail level. RESULTS: OUCAT included 123 items, of which 117 items could effectively distinguish novices from experts (P<0.05). The internal consistency was represented by the Cronbach's α coefficient (0.978). The inter-rater reliability was high, with XY being 0.868, MC being 0.877, and DT being 0.937 (P<0.001). Test-retest reliability was 0.732 (P=0.001). The performance of experts was significantly better than experienced trainees, and the performance of experienced trainees was significantly better than novices (70.3±10.7 vs. 39.8±15.0 vs. 20.5±10.6, P<0.001). The pass/fail level determined by contrast group method was 45 points. The passing rate of novices, experienced trainees and experts was 0% (0/21), 31.8% (14/44), and 100% (24/24), respectively. CONCLUSION: Simulator-based OUCAT exhibits good reliability and validity in assessing obstetric ultrasound skills.

4.
Am Heart J ; 264: 10-19, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37276913

RESUMO

BACKGROUND: Combined antihypertensive therapy has obvious advantages over single drug therapy. Hypertension guidelines fully affirm the efficacy of dual combination in initial antihypertensive therapy. Recent studies have also pointed out that the quadruple combination of very low-dose antihypertensive drugs is superior to single drugs. However, whether low-dose quadruple therapy is better than dual combination is unknown. OBJECTIVE: To evaluate and compare the efficacy and safety of half-dose quadruple therapy vs standard-dose dual therapy in the initial treatment of hypertensive patients with systolic/diastolic blood pressure 140-179/90-109 mm Hg. METHODS: A randomized double-blind crossover clinical trial will be conducted to compare the efficacy and safety of low-dose quadruple antihypertensives (irbesartan 75 mg + metoprolol 23.75 mg + amlodipine 2.5 mg + indapamide 1.25 mg) with standard-dose dual antihypertensives (irbesartan 150 mg + amlodipine 5 mg) in the initial treatment of patients with mild to moderate hypertension (140-179/90-109 mm Hg). Ninety patients are required and will be recruited and randomly assigned in a 1:1 ratio to 2 crossover groups. Two groups will receive a different combination therapy for 4 weeks, then switch to the other combination therapy for 4 weeks, with a 2-week wash-out. The patients will be followed up for 4 weeks to compare the antihypertensive effects and related adverse effects of the 2 antihypertensive combination treatments. CONCLUSIONS: We present the rationale for the design of the QUADUAL trial. The trial started in July 2022 and is expected to be completed by August 2023. The study aims to evaluate if an initial treatment regimen of quadruple combination of half-dose blood pressure medications will result in greater reduction in blood pressure and fewer side effects compared to standard dose dual therapy. REGISTRATION: www. CLINICALTRIALS: gov (NCT05377203).


Assuntos
Anti-Hipertensivos , Hipertensão , Humanos , Anti-Hipertensivos/uso terapêutico , Irbesartana , Estudos Cross-Over , Tetrazóis/uso terapêutico , Hipertensão/tratamento farmacológico , Anlodipino/uso terapêutico , Pressão Sanguínea , Método Duplo-Cego , Resultado do Tratamento , Quimioterapia Combinada , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Food Sci Biotechnol ; 32(7): 969-977, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37123070

RESUMO

Microwave-vacuum drying performance and energy consumption of Camellia oleifera seeds were studied in this paper. The effects of microwave power, vacuum pressure and loading quantity were evaluated and discussed. Orthogonal experiments were also conducted to optimize the drying process. A new drying model based on the weibull distribution model was developed. Results showed that the microwave-vacuum drying process was dominated by internal water diffusion and surface water evaporation. As the microwave power and vacuum pressure increased and the loading quantity decreased, the drying time and energy consumption both decreased. However, too low or too high microwave power would increase the energy consumption. The optimal microwave-vacuum drying conditions were found to be a loading quantity of 150 g, a microwave power of 350 W and a vacuum pressure of 0.09 MPa. The developed drying model and the calculated scale and shape parameter were all consistent with experimental results.

6.
ACS Appl Mater Interfaces ; 15(19): 23286-23298, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37139664

RESUMO

Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has attracted widespread attention in solar generation due to its unique all-in-one photothermoelectric effect. However, the poor photothermal conversion, low conductivity, and unsatisfied mechanical properties limit its practical application. Herein, ionic liquids (IL) were first used to improve the conductivity of PEDOT:PSS through ion exchange, then surface-charged nanoparticles SiO2-NH2 (SiO2+) were added to promote the dispersion of IL and as a thermal insulator to decrease thermal conductivity. It resulted in a largely enhanced electrical conductivity and decreased thermal conductivity of PEDOT:PSS simultaneously. The obtained PEDOT:PSS/Ionic Liquid/SiO2+ (P_IL_SiO2+) film generated an excellent photothermal conversion of 46.15 °C, which improved ∼134 and ∼82.3% compared with PEDOT:PSS and PEDOT:PSS/Ionic Liquid (P_IL) composites, respectively. In addition, the thermoelectric performance increased by ∼270% more than P_IL films. As a result, the photothermoelectric effect for the self-supported three-arm devices produced an enormous output current and power of ∼50 µA and 13.57 nW, respectively, which showed significant improvement compared with other PEDOT:PSS films reported in the literature. Furthermore, the devices demonstrated outstanding stability with an internal resistance variation of less than 5% after 2000 cycles of bending. Our research offered significant insights into the flexible, high-performance, all-in-one photothermoelectric integration.

7.
Neurochem Res ; 48(2): 591-603, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36222959

RESUMO

2-(2-benzofu-ranyl)-2-imidazoline (2-BFI) is a drug that has attracted much attention in recent years. It has a therapeutic effect on brain diseases in animal models such as Alzheimer's disease and cerebral infarction. However, whether 2-BFI affords neuroprotection against the toxicity of fluoride, which can cross the blood-brain barrier and cause neurological dysfunction is not known. We investigated the cell viability and apoptosis of SH-SY5Y cells and primary cultures of cortical neurons exposed to fluoride, and 2-BFI was used to protect both two kinds of cells against the effects of fluoride. We found that 2-BFI can provide neuroprotection on SH-SY5Y cells and primary cultures of cortical neurons upon fluorosis by maintaining the stability of endoplasmic reticulum-mitochondria contact sites and inhibiting activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome. This study may provide a new method for protecting against the neurotoxicity induced by fluoride exposure.


Assuntos
Inflamassomos , Neuroblastoma , Animais , Humanos , Neuroproteção , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fluoretos/toxicidade , Mitocôndrias , Retículo Endoplasmático
8.
J Surg Educ ; 80(3): 407-419, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36333171

RESUMO

OBJECTIVE: Our object was to comprehensively analyze the existing body of evidence to evaluate the Stop the Bleed (STB) course effectiveness and satisfaction and find the direction of improvement for the future. STUDY DESIGN: A literature search with the term "Stop the Bleed" in the electronic databases PubMed, Web of Science, EMBASE, Cochrane Library was performed, retrieving records from January 1, 2013 to April 13, 2022 based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram. In addition, all selected papers' references were examined for qualified studies that were missed during the first search. Original publications were included that reported on (1) clinical studies of the STB course implementation; and (2) studies comparing students' hemostasis ability and attitude (comfort, confidence, and willingness) before and after the STB course. The literature search and data extraction were done independently by 2 writers. To establish consensus, disagreements will be handled with the help of a third reviewer. For data synthesis, the most inclusive data from studies with repeated data were abstracted. Changes in hemostasis questionnaire scoring and operation evaluation after the STB course were the main outcomes. RESULTS: This systematic review and meta-analysis includes 36 trials with a total of 11,561 trainees. Thirty-one of them were undertaken in the USA, while the other 5, accounting for 13.9%, were conducted in other regions. Among various evaluation methods, 3 trials with 927 trainees indicated that scores of correct uses of tourniquet significantly increased after the STB course (mean difference of post versus pre groups, 44.28; 95% CI 41.24-47.32; p < 0.001). Significant difference was also observed in the willingness to apply a hemostatic dressing in a real-world situation (risk ratio for post versus pre groups, 1.28; 95% CI 1.08-1.52; p = 0.004) (7 studies and 2360 participants). The results indicate that hemostasis knowledge and skills after the STB course had improved, but statistics indicated that STB courses implemented in the USA were more effective than other regions. CONCLUSIONS AND RELEVANCE: Meta-analysis showed that comparison before and after the STB course were significantly different. However, the outcome measures in each study were different and could not, therefore, be compiled in all cases. The effectiveness and worth of implementation of STB in different countries should be continuously evaluated in the future.


Assuntos
Hemorragia , Estudantes , Humanos , Hemorragia/terapia , Processos Mentais , Inquéritos e Questionários , Satisfação Pessoal
9.
Journal of Preventive Medicine ; (12): 444-447, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-973457

RESUMO

Objective@#To investigate the status and influencing factors of disease uncertainty among caregivers of colorectal cancer patients receiving chemotherapy, so as to provide insights into psychological interventions among caregivers. @*Methods@#Caregivers of colorectal cancer patients hospitalized in Hunan Cancer Hospital, the Third Xiangya Hospital and the Second Xiangya Hospital for chemotherapy from March 2020 to December 2021 were recruited. Caregivers' demographics, health status, medical and nursing support and social support, as well as patients' demographics, frequency of chemotherapy and disease stage were collected using questionnaire surveys. Caregivers' disease uncertainty was evaluated using Chinese version of the Uncertainty in Illness Scale for Family Members, and factors affecting caregivers' disease uncertainty were identified using a multivariable linear regression model.@*Results@#A total of 318 caregivers were enrolled, including 115 men (36.16%) and 203 women (63.84%), with a mean age of (45.89±6.57) years, and there were 186 caregivers as patients' spouses (58.49%). The mean score of disease uncertainty was (86.65±10.82) points, and the scores of the unpredictability dimension, uncertainty dimension, complexity, and lack of information dimension were (3.21±0.35), (2.98±0.48), (2.84±0.49) and (2.36±0.59) points, respectively. There were 285 participants with a high level of disease uncertainty (89.62%), and multivariable linear regression analysis identified social support (β′=-0.199), medical and nursing support (β′=-0.118), patient's age (β′=-0.155) and stage Ⅲ and Ⅳ of colorectal cancer (β′=0.151) as factors affecting caregiver's disease uncertainty.@*Conclusion@#Caregivers of colorectal cancer patients with chemotherapy have a high level of disease uncertainty, which is affected by social support, medical and nursing support, patient's age and duration of disease.

10.
Front Cardiovasc Med ; 9: 1061240, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36568551

RESUMO

Background: To examine the association of hypertension (HBP) and its control with atrial fibrillation (AF) and how patient sex affects this association. Materials and methods: A case control study of patients admitted to our hospital from 2015 to 2019 was conducted. Patients were divided into subgroups according to their blood pressure (BP) levels and control status, in which odd ratios (OR) by sex for AF was estimated using a logistic regression model and restrictive cubic splines before and after propensity score matching. Results: A total of 3,212 patients with AF and 8,307 without AF were investigated. Compared to patients with normal BP, patients with HBP had more AF [OR = 1.75 (1.52-2.02), OR = 2.66 (2.24-3.15), and OR = 4.30 (3.40-5.44) in patients with grade 1, 2, and 3 HBP, respectively]. In HBP patients with grade 3, the OR of AF was much higher in women than in men (OR = 7.15, 95% CI: 4.43-11.50 vs. OR = 2.48, 95% CI: 1.66-3.72). BP over 133.1/79.9 mmHg in men or 127.1/75.1 mmHg in women was positively associated with AF. In patients with HBP, uncontrolled BP was more associated with AF (OR = 3.00, 95% CI: 2.53-3.56), especially in women (OR = 3.09, 95% CI: 2.27-4.19). BP and prevalence of AF correlated with each other positively in patients admitted to a cardiology ward. Lowering BP to 145.1/85.8 mmHg in men or 140.5/82.5 mmHg in women led to less AF. Conclusion: There is more significant relationship between HBP and AF in female patients. A lower and individualized BP target may be formulated to prevent AF in women.

11.
BMC Neurol ; 22(1): 482, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517761

RESUMO

BACKGROUND AND AIMS: Cerebral microbleeds (CMBs) increase the risk of stroke occurrence and recurrence,and affect the prognosis of stroke patients. Therefore, identifying biological markers that predict CMBs after stroke is urgently needed. This study explored whether high levels of lipoprotein-associated phospholipase A2(Lp-PLA2) are associated with an increased risk of CMBs in patients with acute ischaemic stroke (AIS). METHODS: From April 2020 to October 2021, we enrolled 242 patients with AIS. At admission, the plasma levels of Lp-PLA2 were measured in all patients as well as the number of CMBs and white matter lesions. According to the results of the Susceptibility Weighted Imaging (SWI), the patients were divided into a CMB group and a no-CMB group. The groups were compared with univariate and multivariate analyses to clarify the correlation between Lp-PLA2 levels and CMBs, and the optimal cut-off value of Lp-PLA2 that predicted CMBs was determined from the receiver-operating characteristic curve. RESULTS: CMBs were detected in 71 (29.3%) of the 242 AIS patients. The median Lp-PLA2 level was 182.79 ng/ml. Using the 1st quartile of Lp-PLA2 levels (the lowest levels) as the reference group, univariate logistic regression analysis showed that individuals in the 4th quartile (the highest levels) had a higher risk of CMBs (odds ratio [OR] = 1.460, 95% confidence interval [CI]: 1.188-1.795, P = 0.000). This correlation persisted after adjusting for relevant risk factors (OR = 1.370, 95% CI: 1.096-1.713, P = 0.006). The optimal cut-off value of Lp-PLA2 that predicted the occurrence of CMBs was 184.36 ng/ml; at this threshold, the sensitivity was 69.0%, and the specificity was 60.2%. CONCLUSIONS: Our data suggest that a high level of Lp-PLA2 in patients with AIS is a potential risk factor for CMBs.


Assuntos
Isquemia Encefálica , Hemorragia Cerebral , AVC Isquêmico , Humanos , 1-Alquil-2-acetilglicerofosfocolina Esterase , Biomarcadores , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia
12.
Fish Shellfish Immunol ; 131: 264-273, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35940542

RESUMO

A 24-h hypoxia exposure experiment was conducted to determine how hypoxia exposure induce liver angiogenesis in largemouth bass. Nitrogen (N2) was pumped into water to exclude dissolved oxygen into 1.2 ± 0.2 mg/L, and liver tissues were sampled during hypoxia exposure of 0 h, 4 h, 8 h, 12 h, 24 h and re-oxygenation for 12 h. Firstly, the results showed that hypoxia exposure promoted the angiogenesis occurrence by immunohistochemical analysis of vascular endothelial growth factor receptor 2 (VEGFR2). Secondly, the concentration of vasodilation factor increased and it's activity was elevated during 8 h exposure, such as nitric oxide (NO) and nitric oxide synthase (NOS) (p < 0.05). Thirdly, hypoxia exposure promoted angiogenesis through up-regulation the expression of matrix metalloproteinase 2 (MMP-2), jagged, protein kinase B (AKT), phosphoinositide-3-kinase (PI3K), mitogen-activated protein kinase (MAPK) at 4 h; contrarily, the expression of inhibiting angiogenesis genes presented up-regulated at 8 h (p < 0.05), such as matrix metalloproteinase inhibitor-2 (TIMP-2), matrix metalloproteinase inhibitor-3 (TIMP-3). Finally, the genes and proteins that regulate angiogenesis presented obvious chronological order. Parts of them promoted the budding and extension of blood vessels were up-regulated during 4 h-8 h (p < 0.05), such as vascular endothelial growth factor a (VEGFA), VEGFR2, monocarboxylic acid transporter 1 (MCT1), CD147, prolyl hydroxylase (PHD), nuclear factor kappa-B (NF-κB); other part of them promoted blood vessel maturation were highly expressed during 12 h-24 h (p < 0.05), such as angiogenin-1 (Ang-1) and angiogenin-2 (Ang-2). In short, acute hypoxia can promote the liver angiogenesis of largemouth bass by HIF - dependent pathway.


Assuntos
Bass , Animais , Bass/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Metaloproteinase 2 da Matriz , Inibidores de Metaloproteinases de Matriz/metabolismo , Hipóxia , Fígado/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
13.
J Cardiovasc Transl Res ; 15(6): 1283-1296, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35648358

RESUMO

Atherosclerosis is a chronic inflammatory disease that poses a huge economic burden due to its extremely poor prognosis. Therefore, it is necessary to explore potential mechanisms to improve the prevention and treatment of atherosclerosis. A disintegrin and metalloprotease 17 (ADAM17) is a cell membrane-bound protein that performs a range of functions through membrane protein shedding and intracellular signaling. ADAM17-mediated inflammation has been identified to be an important contributor to atherosclerosis; however, the specific relationship between its multiple regulatory roles and the pathogenesis of atherosclerosis remains unclear. Here, we reviewed the activation, function, and regulation of ADAM17, described in detail the role of ADAM17-mediated inflammatory damage in atherosclerosis, and discussed several controversial points. We hope that these insights into ADAM17 biology will lead to rational management of atherosclerosis. ADAM17 promotes vascular inflammation in endothelial cells, smooth muscle cells, and macrophages, and regulates the occurrence and development of atherosclerosis.


Assuntos
Aterosclerose , Células Endoteliais , Humanos , Células Endoteliais/metabolismo , Proteína ADAM17/metabolismo , Aterosclerose/metabolismo , Miócitos de Músculo Liso/metabolismo , Inflamação/metabolismo , Transdução de Sinais , Proteínas de Membrana
14.
Micromachines (Basel) ; 13(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35630260

RESUMO

The monolithic microwave integrated circuit (MMIC) power amplifiers serve an essential and critical role in RF transmit/receive (T/R) modules of phased array radar systems, mobile communication systems and satellite systems. Over recent years, there has been an increasing requirement to develop wideband high-efficiency MMIC high power amplifiers (HPAs) to accommodate wideband operation and reduce power consumption. This paper presents a wideband high efficiency MMIC HPA for Sub-6-GHz applications using a 0.25-µm gate-length D-mode GaN/SiC high electron mobility transistor (HEMT) process. The amplifier consists of two stages with two HEMT cells for the driver stage and eight HEMT cells for the power stage. To obtain a flat gain while maintaining the wideband characteristic, a gain equalization technique is employed in the inter-stage matching circuit. Meanwhile, a low-loss output matching network is utilized to ensure high efficiency. The fabricated HPA occupies a compact chip area of 14.35 mm2 including testing pads. Over the frequency range of 2-6 GHz, measured results of this HPA show a saturated continuous wave (CW) output power of 44.4-45.2 dBm, a power added efficiency (PAE) of 35.8-51.3%, a small signal gain of 24-25.5 dB, and maximum input and output return losses of 14.5 and 10 dB, respectively.

15.
Artigo em Inglês | MEDLINE | ID: mdl-35564423

RESUMO

BACKGROUND: The world faces vast health challenges, and urban residents living in high-density areas have even greater demand for healthy lifestyles. METHODS: Based on the data of points of interest, a field survey, and an interview, we explored the healthy community-life circle in the downtown area of Chengdu, China from two perspectives: objective measurement and subjective perception of residents. We evaluated the coverage rate and convenience in accessing eight types of health service facilities within a 15-min walk using linear and logistics regression models to explore the degree of resident satisfaction with facilities and influencing factors. RESULTS: Results showed significant differences in coverage rates between different districts. The overall convenience in accessing health service facilities decreased gradually from the city center to the outskirts. The social environment, the layout of health service facilities, and residents' travel habits were related to health service facility satisfaction. Results also showed significant differences in various facilities' accessibility satisfaction between objective measurement and residents' perception measurement. Compared with subjective measurement, the objective measurements of accessibility for sports venues (objectively measured average minus perceived average: -1.310), sports zones (-0.740), and specialized hospitals (-1.081) were lower; those for community hospitals (0.095), clinics (1.025), and pharmacies (0.765) were higher; and facility accessibility measured by subjective perception had a more significant impact on health facility satisfaction. Pharmacies (OR: 1.932) and community hospitals (OR: 1.751) had the largest impact among the eight types of facilities. CONCLUSION: This study proposed to construct a healthy community-life circle with a category and hierarchy system.


Assuntos
Nível de Saúde , Satisfação Pessoal , China , Cidades , Pesquisa Empírica
16.
BMC Nurs ; 21(1): 88, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428288

RESUMO

BACKGROUND: The high prevalence of burnout among nurses produces huge health service losses. Existing literature found that occupational stressors and low levels of job satisfaction were related to burnout, whilst personality traits such as type A personality and neuroticism influenced occupational stressors, job satisfaction, and burnout. The purpose of this study was to investigate the mediating effect of job satisfaction on the relationship between occupational stressors and burnout among Chinese older nurses, and explore the moderating effects of type A personality and neuroticism on the relationships among occupational stressors, job satisfaction and burnout. METHODS: A cross-sectional study was conducted in five provinces and municipalities (mainly in Shandong) in China. A total of 527 female older nurses (age≧40) were included in this study. Structural equation modelling (SEM) approach was employed to investigate the mediating effect of job satisfaction on the relationship between occupational stressors and burnout. Multi-group analysis was conducted to explore the moderating effects of type A personality and neuroticism on the relationships among occupational stressors, job satisfaction and burnout. RESULTS: Both nurses with high type A personality and high neuroticism had higher occupational stressors, higher burnout and lower job satisfaction. Occupational stressors had direct effect (ß = 0.29, P = 0.001) and indirect effect mediated by low levels of job satisfaction (ß = 0.25, P = 0.001) on burnout. Type A personality had significant moderated effect (P = 0.007) on the relationships among occupational stressors, job satisfaction and burnout, whereas the moderated effect of neuroticism was not significant. CONCLUSIONS: Low levels of job satisfaction mediated the relationship between occupational stressors and burnout among Chinese older nurses, and both the direct and indirect effect of occupational stressors on burnout were moderated by type A personality. Hospital administrators should take specific measures such as transferring older nurses to easier positions to reduce their occupational stress, thereby increasing their job satisfaction and reducing their burnout, which is especially important for the older nurses with high type A personality.

17.
BMC Med Educ ; 22(1): 281, 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35421954

RESUMO

BACKGROUND: The "Stop the Bleed" (STB) campaign has achieved remarkable results since it was launched in 2016, but there is no report on the teaching of an STB course combined with a trauma patient simulator. This study proposes the "problem-, team-, and evidence-based learning" (PTEBL) teaching method combined with Caesar (a trauma patient simulator) based on the STB course and compares its effect to that of the traditional teaching method among outstanding doctoral candidates training in haemostasis skills. METHOD: Seventy-eight outstanding doctoral candidate program students in five and eight-year programs were selected as the research subjects and were randomly divided into a control group (traditional teaching method, n = 34) and an experimental group (PTEBL teaching method combined with Caesar, n = 44). Their confidence in their haemostasis skills and willingness to rescue injured victims were investigated before and after the course in both groups. RESULT: Students' self-confidence in their STB skills and the willingness to rescue improved after the class in both groups. Compared with the control group, students in the experimental group were more confident in compressing with bandages and compressing with a tourniquet after a class (compressing with bandages: control group 3.9 ± 0.8 vs. experimental group 4.3 ± 0.7, P = 0.014; compressing with a tourniquet: control group 3.9 ± 0.4 vs. experimental group 4.5 ± 0.8, P = 0.001) More students in the experimental group than the control group thought that the use of Caesar for scenario simulation could improve learning (control group 55.9% vs. experimental group 81.8%, P = 0.024), and using this mannequin led to higher teacher-student interaction (control group 85.3% vs. experimental group 97.7%, P = 0.042). The overall effectiveness of the teaching was better in the experimental group than in the control group (control group 85.3% vs. experimental group 97.7%, P = 0.042). There was a significant positive correlation between teacher-student interactions and the overall effectiveness of teaching (R = 1.000; 95% CI, 1.000-1.000; P < 0.001). CONCLUSION: The PTEBL teaching method combined with Caesar can effectively improve student mastery of STB skills and overcome the shortcomings of traditional teaching methods, which has some promotional value in the training of outstanding doctoral candidates in STB skills.


Assuntos
Hemorragia , Aprendizagem , Simulação por Computador , Hemorragia/prevenção & controle , Humanos , Estudantes , Ensino
18.
ChemSusChem ; 15(8): e202102189, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35289479

RESUMO

While extensive research has driven the rapid efficiency trajectory noted to date for organic-inorganic perovskite solar cells (PSCs), their thermal stability remains one of the key issues hindering their commercialization. Herein, a significant reduction in surface defects (a precursor to perovskite instability) could be attained by introducing triphenylphosphine (TPP), an effective Lewis base passivator, to the vulnerable perovskite/spiro-OMeTAD interface. Not only did TPP passivation enable a high power conversion efficiency (PCE) of 20.22 % to be achieved, these devices also exhibited superior ambient and thermal stability. Unlike the pristine device, which exhibited a sharp descend to 16 % of its initial PCE on storing in relative humidity of 10 %, at 85 °C for more than 720 h, the TPP-passivated devices retained 71 % of its initial PCE. Hence, this study presents a facile yet excellent approach to attain high-performing yet thermally stable PSCs.

19.
Transl Pediatr ; 11(2): 239-248, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35282024

RESUMO

Background: Epilepsy is a chronic disease that can reduce the quality of life in children because it can cause memory loss, learning difficulties, mental and behavioral abnormalities, and social disorders. The purpose of this study was to explore the effect of the hospital-community-family linkage continuous nursing model in the nursing of children with epilepsy. Methods: Data for 136 children with epilepsy who were hospitalized in the neurology clinic or neurology ward of Wuxi Children's Hospital from January 2018 to January 2021 were retrospectively analyzed. According to the nursing mode after discharge, the children were divided into 65 cases in the observation group (hospital-community-family linkage continuous nursing model) and 71 cases in the control group (routine nursing model). The compliance with nursing, cognitive function, resilience, and quality of life of the two groups were compared before and after intervention, and the influencing factors of children's quality of life were analyzed. Results: The follow-up visit 6 months after discharge found that the scores for compliance, resilience, and quality of life in the observation group were significantly higher than those in the control group (P<0.05). The correlation analysis between quality of life, each child's general data, and the nursing model found that the total score of quality of life was correlated with incidence frequency, family per capita income, and the nursing model. Conclusions: The adoption of a hospital-community-family linkage continuous nursing model can improve the compliance, resilience, and quality of life of children with epilepsy.

20.
Sci Total Environ ; 821: 153388, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35085633

RESUMO

Parks have become important spaces for supplying cultural ecosystem services (CESs) in cities, and satisfying various needs of different age groups in parks has become a critical issue. Many studies focused on the environmental preferences and behaviours of different age groups in parks. However, results revealing the differences in value demand and acquisition between elderly and youth from a landscape spatial environmental perspective are limited. In this study, the same number of youth and elderly volunteers were recruited, according to the value-labelled photo fed back after their self-driven tour in the Huanhuaxi Urban Forest Park in Chengdu, China. In addition, this study explored the relationship between the perceived CES needs of the youth and elderly and the landscape spatial environment in the urban park ecosystem with the help of the Social Values for Ecosystem Services model. Results showed that, in comparison, to obtain recreation value, playgrounds, pavilions and squares were more important for the elderly, whereas topography, rivers, landscape sketches and trails were more important for the youth. Moreover, in terms of the sense of place, lakes and wetlands were more important for the elderly, whereas landscape sketches and playgrounds were more important for the youth. Furthermore, for the delivery of therapeutic value, squares were more important for the elderly. Spatially, the areas of lakes or wetlands with geographical combinations of landscape sketches and flowers were the high-value spots for supplying multiple CESs in urban parks. Then, squares, rivers, playgrounds and forests were the focus areas where the value identification of the two age groups diverges. This study emphasises the differences in demand and acquisition of cultural added value provided by the environment between the young and the old. The study provides a basis for more targeted land management and landscape planning of urban parks.


Assuntos
Ecossistema , Parques Recreativos , Adolescente , Idoso , China , Cidades , Florestas , Humanos
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