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INTRODUCTION: Patients frequently suffer from debilitating chronic postsurgical pain (CPSP) subsequent to thoracoscopic surgery. The impact of postoperative dexmedetomidine infusion on CPSP remains elusive. This study aimed to scrutinize the effect of dexmedetomidine on both 1-year incidence of CPSP and the quality of recovery after thoracoscopic pulmonary nodule surgery. METHODS: This retrospective analysis encompassed clinical and follow-up data from 1148 patients undergoing thoracoscopic pulmonary nodule surgery at our institution between September 2021 and August 2022. Depending on whether dexmedetomidine was infused intravenously or not on the first night after surgery, patients were stratified into the dexmedetomidine group or the control group, with propensity score matching applied to harmonize baseline characteristics. Comparative analysis sought to delineate distinctions of CPSP and recovery quality 1 year after surgery. RESULTS: Following propensity score matching, a cohort of 258 patients in each group underwent analysis. Comparisons after matching revealed no statistically significant disparities in 1-year CPSP incidence [76/258 (29.5%) versus 78/258 (30.2%), P = 0.847], moderate-to-severe pain occurrence [17/76 (22.4%) versus 22/78 (28.2%), P = 0.405], neuropathic pain occurrence [11/76 (14.5%) versus 11/78 (14.1%), P = 0.948], and postoperative recovery quality assessed by 12-Item Short Form Health Survey (SF-12) score (113.1 [107.2, 116.0] versus 113.0 [107.4, 116.0], P = 0.328). Multivariate logistic regression analysis encompassing the entire cohort identified being female [odds ratio (OR) 2.10, 95% confidence interval (CI) 1.59-2.79, P < 0.001) and postoperative rescue analgesia (OR 1.47, 95% CI 1.09-1.96, P = 0.010) as risk factors for CPSP, while intraoperative fentanyl dosage (OR 0.92, 95% CI 0.87-0.98, P = 0.006) emerged as a protective factor. CONCLUSION: The prolonged administration of dexmedetomidine did not yield discernible amelioration in either 1-year CPSP or the recovery quality after thoracoscopic surgery. Noteworthy risk factors for CPSP encompassed female sex, postoperative rescue analgesia, and diminished fentanyl dosage intraoperatively.
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BACKGROUND: Tooth-supported surgical guides have demonstrated superior accuracy compared with bone-supported guides. This study aimed to modify the fabrication of tooth-supported guides for compatibility with tumor resection procedures and investigate their accuracy. METHODS: Patients with tumors who underwent osteotomy with the assistance of modified tooth- or bone-supported surgical guides were included. Virtual surgical planning (VSP) was employed to align three dimensional (3D) models extracted from intraoperative computed tomography (CT) images. The distances and angular deviations between the actual osteotomy plane and preoperative plane were recorded. A comparative analysis of osteotomy discrepancies between tooth-supported and bone-supported guides, as well as among tooth-supported guides based on CT, cone-beam CT (CBCT), or intraoral scanner (IOS) was conducted. The factors influencing the precision of the guides were analyzed. RESULTS: Sixty patients with 81 resection planes were included in this study. In the tooth-supported group, the mean deviations in the osteotomy plane and angle were 1.39 mm and 4.30°, respectively, whereas those of the bone-supported group were 2.16 mm and 4.95°. In the tooth-supported isotype guide groups, the mean deviations of the osteotomy plane were 1.39 mm, 1.47 mm, 1.23 mm across CT, CBCT, and IOS, respectively. The accuracy of the modified tooth-supported guides remained consistent regardless of number and position of the teeth supporting the guide and location of the osteotomy lines. CONCLUSIONS: The findings indicate that the modified tooth-supported surgical guides demonstrated high accuracy in the maxillofacial region, contributing to a reduction in the amount of surgically detached soft tissue.
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Objective: The purpose of this retrospective study was to describe the clinicopathological characteristics of primary adenoid cystic carcinoma (ACC) of the palate and to identify the factors affecting prognosis. Methods: The medical records of 85 patients with primary ACC of the palate treated with surgery, with or without adjuvant radiotherapy/chemotherapy, from 2009 to 2019 were reviewed. The relationship of different clinical parameters with locoregional recurrence (LR), distant metastasis (DM), and overall survival (OS) were analyzed. Results: Median follow-up time was 44.6 months. LR and DM rates were 24.7% and 25.9%, respectively, and the 5-year OS and disease-free survival (DFS) rates were 85.9% and 55.1%, respectively. Multivariate analysis showed that positive margins were independently associated with the risk of LR (p < .001). Positive margins (p = .001) and high histological grade (p = .031) were significantly associated with shorter OS. Conclusion: Positive surgical margins are a strong adverse prognostic factor affecting LR and OS in patients with ACC; apart from that, high histopathological grade is an independent predictor of poor OS. Level of Evidence: Level 3 (Prognosis - Cohort study).
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BACKGROUND AND PURPOSE: Salivary gland cancers (SGCs) are hard to treat when inoperable, and sole brachytherapy appears to be a promising therapeutic strategy. This study aimed to evaluate the effectiveness, safety, and capability of pain palliation using sole brachytherapy for inoperable, recurrent, and irradiated SGCs. MATERIALS AND METHODS: Patients with inoperable SGCs treated using sole brachytherapy at Peking University School and Hospital of Stomatology were retrospectively included. Patients were divided into primary and recurrent groups and irradiated and non-irradiated groups. Local control (LC), overall survival (OS), radiation-relevant toxicities, and Visual Analogue Scale (VAS) score for pain, were recorded and evaluated. RESULTS: A total of 176 patients from 2006 to 2020 were included. The 5-year LC rate was 48.6 %; for the primary, recurrent, non-irradiated and irradiated groups, the rates were 72.6 %, 39.5 %, 56.8 %, and 34.5 %, respectively. The 5-year OS rates was 52.6 %; for the primary, recurrent, non-irradiated, and irradiated groups, the rates were 62.9 %, 48.6 %, 58.9 %, and 42.3 %, respectively. The mean ± standard deviation of posttreatment VAS score of pain was 2.154 ± 2.989, which was significantly decreased from the score of 6.923 ± 2.280 prior to brachytherapy. Skin hyperpigmentation, mucositis, and dysphagia were the most frequently reported adverse events. CONCLUSIONS: Brachytherapy as a sole modality, was retrospectively proven effective and safe in the management of inoperable SGCs and was beneficial in multiple irradiation and pain control.
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Braquiterapia , Neoplasias das Glândulas Salivares , Humanos , Braquiterapia/efeitos adversos , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/radioterapia , Dosagem Radioterapêutica , Dor/etiologia , Recidiva Local de NeoplasiaRESUMO
In this work, one-step synthesis of high-performance C-A-S-H (calcium alumina silicate hydrate) seeds from low-calcium fly ash (FA) and carbide slag (CS) by 7 days of mechanochemical mixing was proposed and used to activate lithium slag (LS) cement. The results showed that the seeding effect of C-A-S-H seeds was increased with the increasing Ca/Si (i.e. from 1.0 to 1.5), i.e. the mortar compressive strength of 1 day and 28 days were increased by 67% and 29% with the addition of 1.0% C-A-S-H nano-seeds at Ca/Si = 1.5 in the presence of polycarboxylate superplasticizer (PCE), respectively. Moreover, the chloride resistance of lithium slag cement was improved significantly, i.e. the electric flux was decreased by more than 30% than that of plain lithium slag cement mortar. The performance difference of various C-A-S-H seeds is mainly attributed to their high proportion and polymerization degree, more stretch and three-dimensional foil-like morphology at high Ca/Si. This study provides guidance for obtaining low-cost and high-performance C-A-S-H seeds from wastes and the highly efficient utilization of LS as supplementary cementitious materials (SCMs) in the future.
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Cinza de Carvão , Lítio , Carbono , Cálcio , Materiais de ConstruçãoRESUMO
Chronic hepatitis B infection remains a significant worldwide health burden, placing persons at risk for hepatocellular cancer and hepatic fibrosis. Chronic hepatitis B virus (CHB) infection is characterized by elevated levels of immunosuppressive regulatory T cells (Tregs), which can inhibit the function of effector T cells and lead to an insufficient immune clearance response against HBV. Theoretically, suppression of Treg cell functionality and percentage could increase anti-HBV reactivity in CHB-infected patients, although this has not yet been explored. We attempted to enhance our previously established anti-CHB protocol utilizing the GM-CSF+IFN-α+rHBVvac regimen (GMI-HBVac) by incorporating mafosfamide (MAF), which has been utilized in anticancer therapy in the past. Intravenous administration of MAF to rAAV8-1.3HBV-infected mice resulted in a dose-dependent reduction of Tregs in the blood, rebounding to pretreatment levels 10 days later. To assess the potential benefit of adding MAF to the anti-CHB protocol, 2 µg/mL MAF was combined with the GMI-HBVac as an anti-Treg treatment in an HBV-infected animal model. When rAAV8-1.3HBV-infected mice were immunized with MAF+GMI-HBVac, peripheral blood Tregs decreased significantly, leading to dendritic cell activation, HBV-specific T cell proliferation, and the upregulation of IFN-gamma-producing CD8+T cells. In addition, MAF+GMI-HBVac vaccination stimulated T cell infiltration in HBV-infected livers. These effects may contribute to an enhanced immune response and the clearance of HBV-associated antigens, including serum HBsAg, serum HBcAg, and HBcAg+ hepatocytes. Overall, this is the first indication that MAF can act as an adjuvant with GMI-HBVac to deplete Tregs in mice with an established CHB infection. This unique therapeutic vaccine regimen produced a functional cure, as revealed by the remarkable clearance of HBsAg.
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The purpose of this study was to investigate the relationship between cognitive function and depressive symptoms among Chinese adults aged 40 years and above, as well as the series of multiple mediating effects of Instrument Activities of Daily Living disability and life satisfaction on this relationship. The data was obtained from the China Health and Retirement Longitudinal Study (CHARLS, 2013-2018), including 6466 adults aged 40 years and above. The mean age of the adults was 57.7 ± 8.5. The SPSS PROCESS macro program was conducted to examine the mediating effects. The results indicated that there was a significant association between cognitive function and depressive symptoms five years later (B = -0.1500, 95%CI: -0.1839, -0.1161), which could also be demonstrated through three mediation pathways: (1) the mediating pathway through IADL disability (B = -0.0247, 95%CI: -0.0332, -0.0171); (2) the mediating pathway through life satisfaction (B = 0.0046, 95%CI: 0.0000, 0.0094); and (3) the chain mediation pathway through IADL disability and life satisfaction (B = -0.0012, 95%CI: -0.0020, -0.0003). Both IADL disability and life satisfaction have been proven to be crucial mediators for the relationship between cognitive function and depressive symptoms five years later. It is necessary to improve individuals' cognitive function and reduce the negative impact of disability on them, which is important to enhance their life satisfaction and prevent depressive symptoms.
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Atividades Cotidianas , Depressão , Adulto , Humanos , Atividades Cotidianas/psicologia , China , Cognição , Depressão/psicologia , População do Leste Asiático , Estudos Longitudinais , Satisfação Pessoal , Pessoa de Meia-Idade , IdosoRESUMO
Asthma poses a significant threat to public health, with an estimated burden of over 334 million people worldwide. Available treatments are often inadequate. We developed a thermo-sensitive hydrogel vaccine containing allergen and FK506 that induced immune tolerance via intranasal administration to treat experimental allergic asthma. The hydrogel delivery system was formulated based on Poloxamer 407 (P407), Carbopol 974P NF, and Polyoxyl 15 hydroxystearate (Kolliphor HS15, HS15). It flowed freely at room temperature and rapidly formed a hydrogel in the nasal cavity once the temperature rose over 33 °C. Ovalbumin and FK506 were slowly released from the hydrogel form and their mucosal residence time was significantly prolonged compared to the liquid formulation. In both an OVA-induced asthma model and an HDM-induced asthma model, the vaccines formulated in hydrogel gave lower levels of eosinophilic inflammation, and airway remodeling. The reduction of lung function was ameliorated, and Foxp3-expressing CD4 + Treg cells were significantly higher. The frequency of Foxp3 + Tregs in lung-draining lymph nodes (dLNs) was correlated with the amelioration. Depletion of Foxp3 + Treg cells abolished the beneficial effects of the allergen/FK506 hydrogel vaccinations. Thus, the allergen/FK506 hydrogel formulation has the potential to be a delivery system for therapeutic allergy vaccines to induce immune tolerance.
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Asma , Vacinas , Humanos , Alérgenos , Asma/tratamento farmacológico , Modelos Animais de Doenças , Fatores de Transcrição Forkhead , Hidrogéis/uso terapêutico , Imunoterapia , Ovalbumina , Linfócitos T Reguladores , Tacrolimo/uso terapêuticoRESUMO
The purpose of this study was to assess the serial multiple mediating effects of subjective well-being and life satisfaction between job satisfaction and depressive symptoms among Chinese adults aged 35-60 years. According to the 2018 China Family Panel Study (CFPS), we finally selected 10,609 respondents (5202 females, and 5407 males) aged 35-60 years old as samples for the study. Correlation analysis was carried out to examine the relationship among job satisfaction, subjective well-being, life satisfaction, and depressive symptoms. Linear regression models were established to analyze the relationship between job satisfaction and depressive symptoms. Serial multiple mediation analysis was conducted by the SPSS macro PROCESS program. The results suggested that job satisfaction was negatively correlated with depressive symptoms among Chinese adults aged 35-60 years. Subjective well-being and life satisfaction mediated the relationships between them, respectively. Furthermore, job satisfaction also had indirect impacts on depressive symptoms through the serial mediating effects of subjective well-being and life satisfaction. The findings revealed that increasing job satisfaction could decrease depressive symptoms through promoting subjective well-being and life satisfaction. The study may offer some meaningful implications for improving the mental health and reducing the risk of depressive symptoms among Chinese adults aged 35-60 years.
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Depressão , Satisfação no Emprego , Masculino , Feminino , Adulto , Humanos , Pessoa de Meia-Idade , Depressão/epidemiologia , Depressão/psicologia , Inquéritos e Questionários , População do Leste Asiático , Estudos Transversais , China/epidemiologia , Satisfação PessoalRESUMO
BACKGROUND: Desmoid tumor (DT) is rare and challenging, often affects the head and neck (HN) region in children, and its appropriate treatments are under-discussed. This study aimed to retrospectively evaluate the long-term effectiveness and safety of 125 I seed brachytherapy for pediatric DT in HN. PROCEDURE: Seven pediatric patients with a median age of three years who suffered from DT in HN treated with 125 I brachytherapy from January 2008 to June 2018 were included. Among these, five underwent sole brachytherapy and the others combined with surgery under prescription doses ranging from 10,000 to 12,000 cGy. The rate of local control (LC), complete response (CR), and partial response (PR) was calculated after evaluation by radiological and pathological means. Radiation-associated toxicities were also evaluated. RESULTS: The LC rate was 7/7 during the follow-up time ranging from 43 to 135 months and with a mean of 57 months. No recurrent lesion was found in the patients receiving surgery combined with brachytherapy. In patients treated with sole brachytherapy, the radiological PR rate and CR rate were 4/5 and 1/5, respectively. In those reaching radiological PR, 3/4 were pathological CR. Slight acute radiation-associated toxicities were observed in all patients, and no late or severe acute toxicity was observed. CONCLUSION: 125 I brachytherapy is effective and safe in the management of pediatric DT in HN as the sole modality or combined with surgery in the long term.
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Braquiterapia , Fibromatose Agressiva , Neoplasias de Cabeça e Pescoço , Humanos , Criança , Pré-Escolar , Braquiterapia/efeitos adversos , Fibromatose Agressiva/radioterapia , Estudos Retrospectivos , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/etiologiaRESUMO
Anodic passivation is a key problem to impair the efficiency of in the electrocoagulation (EC) process. Process intensification of EC has attracted increasingly greater attention. In this work, a novel centrifugal electrode reactor was designed and applied in EC process to enhance the treatment of simulated heavy metal wastewater using aluminum anode. Results showed that the removal efficiency of heavy metals was significantly improved by the centrifugal electrodes, compared with the stationary electrodes. Electrochemical behavior of centrifugal electrodes was analyzed by an improved rotating disk electrode system. Anodic polarization behavior of aluminium showed a typical characteristic of dissolution in centrifugal electrodes, rather than passivation in static condition. Anode dissolution was controlled by the diffusion of Cl- ion that was enhanced by centrifugal electrodes. Thus, anode passivation was reduced. In addition, the kinetics analysis indicated that the removal of heavy metals in EC by centrifugal electrodes conformed to Variable-Order-Kinetic (VOK) model based on the Langmuir adsorption.
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Metais Pesados , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias/análise , Cinética , Eletrodos , Metais Pesados/análise , Eletrocoagulação/métodos , Alumínio/análise , Purificação da Água/métodos , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos/métodosRESUMO
Objectives: The efficacy of treatments targeting recurrent or metastatic head and neck squamous cell carcinoma are unsatisfactory in practice for patients with a ECOG PS score ≥ 2. Thus, this study retrospectively evaluated the safety and efficacy of a programmed cell death 1 inhibitor (tislelizumab) combined with an epidermal growth factor receptor inhibitor (nimotuzumab) in treating patients with a PS score ≥ 2 who suffer from recurrent or metastatic oral squamous cell carcinoma (OSCC). Materials and methods: Fifteen patients were treated with tislelizumab (200 mg IV Q3W) and nimotuzumab (200 mg IV Q3W). Programmed cell death-ligand 1 (PD-L1) expression in tumor biopsies was assessed with immunohistochemistry. Whole-exome sequencing was used to evaluate treatment efficacy based on PD-L1 expression and gene mutation. Results: At a median follow-up of 9.6 months, median overall survival was 10.1 months, and median progression-free survival was 4.0 months. Overall response rate was 40%, with 6/15 patients achieving partial response. Eight patients exhibited nine adverse events, eight out of nine being grade 2 and the remaining being grade 3. Whole-exome sequencing showed that DYNC1I2, THSD7A, and FAT1 mutations were associated with patient prognosis. Conclusion: Combination therapy involving tislelizumab plus nimotuzumab is a promising, low-toxicity treatment for recurrent or metastatic OSCC in patients with a PS score ≥ 2.
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Respiratory syncytial virus (RSV) infection in children is the most common viral respiratory infection and can cause severe lung damage or death. There is no licensed vaccine for preventing RSV infection. Previously we demonstrated that an RSV vaccine, BARS13, consisting of recombinant G protein from E. coli plus cyclosporine A (CsA) as an immune-modulator, can protect animals from RSV challenge without inducing vaccine-enhanced disease (VED). To maximize the efficacy of such a vaccine, we introduced RSV pre-fusion F protein (pre-F) to form a new vaccine comprised of the pre-F and G proteins with the CsA. Two intramuscular immunizations with the vaccine induced a higher level of neutralizing antibodies against RSV and protected mice from RSV challenge without incurring VED. Interestingly, the addition of the pre-F to the vaccine facilitated anti-G antibody production and protection from RSV infection mainly via induction of antibodies against the central conserved domain (CCD) of the G protein which correlated with blocking the CX3C-CX3CR1 interaction. A 15 amino acid sequence (FP4) within the F2 region of pre-F served as a CD4+ Th epitope to facilitate the anti-G antibody response. Collectively, such a combination of the FP4 peptide with the G protein and CsA provides a novel strategy for developing a safe and maximally effective recombinant G protein-containing RSV vaccine.
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BACKGROUND AND PURPOSE: To determine the neck management of tongue cancer, this study attempted to construct an artificial neural network (ANN)-assisted model based on computed tomography (CT) radiomics of primary tumors to predict neck lymph node (LN) status in patients with tongue squamous cell carcinoma (SCC). MATERIALS AND METHODS: Three hundred thirteen patients with tongue SCC were retrospectively included and randomly divided into training (60%), validation (20%) and internally independent test (20%) sets. In total, 1673 feature values were extracted after the semiautomatic segmentation of primary tumors and set as input layers of a classical 3-layer ANN incorporated with or without clinical LN (cN) status after dimension reduction. The receiver operating characteristic (ROC) curve, accuracy (ACC), sensitivity (SEN), specificity (SPE), area under curve (AUC) and Net Reclassification Index (NRI), were used to evaluate and compare the models. RESULTS: Four models with different settings were constructed. The ACC, SEN, SPE and AUC reached 84.1%, 93.1%, 76.5% and 0.943 (95% confidence interval: 0.891-0.996, p<.001), respectively, in the test set. The NRI of models compared with radiologists reached 40% (p<.001). The occult nodal metastasis rate was reduced from 30.9% to a minimum of 12.7% in the T1-2 group. CONCLUSION: ANN-based models that incorporated CT radiomics of primary tumors with traditional LN evaluation were constructed and validated to more precisely predict neck LN metastasis in patients with tongue SCC than with naked eyes, especially in early-stage cancer.
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Carcinoma de Células Escamosas , Neoplasias da Língua , Carcinoma de Células Escamosas/diagnóstico por imagem , Humanos , Metástase Linfática/diagnóstico por imagem , Redes Neurais de Computação , Estudos Retrospectivos , Neoplasias da Língua/diagnóstico por imagemRESUMO
Anodic passivation is a key problem to reduce the efficiency of electrocoagulation (EC) process. Super-gravity technology was introduced into EC process to enhance the treatment of heavy metal wastewater using pure aluminum electrode. The results showed that the removal ratio of Cu increased, and the cell voltage decreased with the increase of gravity coefficient, suggesting a promoting effect of super-gravity field on electrocoagulation process. Electrochemical behavior of aluminium anode in super-gravity field was analyzed by potentiodynamic polarization, cyclic voltammetry and electrochemical impedance spectroscopy. It was found that anodic polarization behavior of aluminium showed a typical characteristic of dissolution in super-gravity, rather than passivation in normal gravity. The type of anode dissolution changed from pitting corrosion to uniform corrosion in super-gravity field. The outer oxidized film of anode was thinning, and more Al3+ ions were released by anode dissolution, which was attributed to the super-gravity enhancement of the mass transfer process of Cl- ions. In addition, X-ray diffraction and Fourier transform infrared spectroscopy indicated that the flocs generated in super-gravity field had amorphous and looser Al-O framework structure. As a result, the efficiency of EC process was improved by super-gravity.
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Alumínio , Águas Residuárias , Cobre , Eletrocoagulação , Eletrodos , Eliminação de Resíduos LíquidosRESUMO
This study explored the relations between children's intergenerational emotional support and subjective well-being (SWB) among Chinese middle-aged (45-60 years old) and elderly people (over 60 years old) and the mediation effect of the sense of social fairness between such associations. Using the 2017 Chinese General Social Survey dataset, a nationally representative survey, we selected 2413 middle-aged and elderly people who are 45 years and older, who suited the study requirements with 1097 males and 1316 females, which accounts for 45.5% and 54.5%, respectively. The average of age was 61.62 years old (SD = 10.45). The mediation analyses were conducted by multivariate regression and the SPSS macro PROCESS program. The results indicated that there was a significant association between children's intergenerational emotional support and subjective well-being of middle-aged and elderly people (ß = 0.0819, p < 0.001). Children's intergenerational emotional support also had an indirect impact on subjective well-being through one path: the mediating role of the sense of social fairness (0.012). Direct effect (0.0699) and mediation effect (0.012) accounting for the total effect proportion was 85.35% and 14.65%, respectively. The findings may offer some meaningful implications for improving subjective well-being of middle-aged and elderly people. Future research should pay attention to the aforementioned factors with more detailed and comprehensive studies.
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Aconselhamento , Emoções , Idoso , Criança , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apoio Social , Inquéritos e QuestionáriosRESUMO
The recycling of packaging plastics is hindered by the various plastic mixtures and their similar surface properties. Plastic separation is a key step to improve recycling efficiency of waste plastics. We proposed a simple and efficient protocol to separate polyethylene terephthalate (PET) from polycarbonate (PC), acrylonitrile-butadienestyrene copolymer (ABS), and polyvinyl chloride (PVC) by converting PET surface from hydrophobicity to hydrophilicity. PET surface was modified by potassiumhydroxide (KOH)and ethylene glycol ((CH2OH)2) with the aid of sonication. Contact angle, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) were used to research the reactions on PET surface. It can be confirmed that the reaction of base-catalyzed transesterification occurs, leading to a hydrophilic PET plastic. We investigated the effects of ultrasonic power, ultrasonic time, (CH2OH)2 dosage, KOH dosage, flotation time, and frother concentration on the flotation separation. The flotation recovery and purity of PET are 98.8% and 100%, respectively when (CH2OH)2 dosage is 10 mL, KOH dosage is 2 g, ultrasonic time is 5 min, ultrasonic intensity is 160 W, flotation time is 4 min, and frother concentration is 52.7 mg/L. This study provided a novel surface modification with reliable mechanisms for the flotation of PET from plastic mixtures.
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Plásticos , Eliminação de Resíduos , Etilenoglicol , Polietilenotereftalatos , Cloreto de Polivinila , Reciclagem , SonicaçãoRESUMO
Although respiratory syncytial virus (RSV) infection in infants and young children is a global public health issue, development of a safe RSV vaccine has been impeded by formalin-inactivated RSV-enhanced respiratory disease (ERD). In developing a safer yet effective RSV vaccine for children, a strategy to decrease over-reactive T cells and increase neutralizing anti-RSV antibodies should be considered. We previously demonstrated that adult mice immunized with RSV recombinant G protein plus low-dose Cyclosporine A (G+ CsA) could, upon subsequent RSV challenge, produce increased levels of antigen-specific T regulatory cells in lungs that overcame the ERD. Neutralizing anti-RSV antibodies that prevented viral infection were also elicited. In this study, we investigated if such a G+ CsA vaccine could provide infant mice with the same protection from RSV infection without ERD. The results showed that the G+ CsA vaccine could prevent RSV infection with only a mild loss of body weight. Importantly, there was nearly normal morphology and no mucus appearance in lung tissues after RSV challenge. These results demonstrate that the G+ CsA vaccine strategy achieved similar benefits in the neonatal prime and infancy boost model as in the adult mouse model. The G+ CsA immunization strategy is potentially safe and effective in neonates and infants because it suppresses the devastating ERD.
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Infecções por Vírus Respiratório Sincicial , Vacinas contra Vírus Sincicial Respiratório , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunidade , Pulmão , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sinciciais RespiratóriosRESUMO
This study developed a novel method, surface pretreatment using sodium hypochlorite along with flotation, to facilitate separation of waste polycarbonate from plastic mixtures for recycling. Surface pretreatment was observed that has an obviously negative effect on the floating ratio of polycarbonate and the floating ratio of poly-methyl-methacrylate, polystyrene, and polyvinylchloride was not affected in flotation, and this difference in floating ratio can be expected to separate polycarbonate from plastic mixtures. The optimum conditions obtained included sodium hypochlorite concentration of 0.05â¯M, pretreatment temperature of 70.0⯰C, pretreatment time of 60.0â¯min, frother dosage of 10.8â¯mg/L, and flotation time of 4.0â¯min. Under optimum conditions, polycarbonate was separated effectively from multiple plastic mixtures, and the purity and recovery were 99.8% and 100.0%, respectively. The major mechanism of surface pretreatment was ascertained by the aid of Fourier transform infrared, scanning electron microscope, energy dispersive spectrometer, and X-ray photoelectron spectroscopy, and the hydrophilic groups, pitting, and protuberances introduced on polycarbonate surface caused the reduced floating ratio of polycarbonate. Accordingly, this method can be expected to improve the recycling quality of waste plastics, and provides technological insights in the environmentally friendly disposal of waste plastics.
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Plásticos , Eliminação de Resíduos , Cimento de Policarboxilato , Reciclagem , Hipoclorito de SódioRESUMO
A novel advanced oxidation process by a combination of Fe(III) and sulfite for surface treatment of waste plastic mixtures is proposed. The Fe(III)/sulfite system has been found to enhance hydrophilicity of the mixed waste plastics, including acrylonitrile butadiene styrene (ABS), polystyrene (PS) and polycarbonate (PC), while it has little effect on hazardous polyvinyl chloride (PVC), thus promoting separation of PVC from the mixed waste plastics by flotation. Radical scavenging experiments indicate that sulfate radicals are the main reactive species. Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) results imply the formation of CO or CO groups on the treated plastics surface except for PVC and a plausible mechanism for oxidizing plastics with sulfate radicals is proposed. PVC with 100.00% recovery and 99.84% purity is achieved under optimum surface treatment conditions of sodium sulfite concentration 10 mM, ferric sulfate concentration 0.4 mM, pH 6.0, temperature 25 °C and treatment time 15 min. Consequently, surface treatment by the Fe(III)/sulfite system is an effective technology for separating hazardous PVC from the mixed waste plastics by flotation.