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OBJECTIVE: This study investigates neuropsychological and psychosocial outcomes in patients with traumatic brain injury (TBI) and post-traumatic epilepsy (PTE) compared to a healthy control group. METHOD: Utilizing a quasi-experimental cross-sectional design, the research involved patients with TBI and PTE referred from a Taiwanese medical center. An age- and education-matched control group of healthy adults without traumatic injuries was also recruited. The study involved analyzing retrospective medical records and applying a comprehensive suite of neuropsychological tests and psychosocial questionnaires. RESULTS: Executive function measures revealed significantly reduced performance in both the TBI and PTE groups compared to controls. Specifically, the MoCA scores were lowest in the PTE group, followed by the TBI group, and highest in the controls. Measures of subjective symptomatology showed comparably elevated levels in both the TBI and PTE groups relative to controls. CONCLUSION: The research suggests that PTE may intensify the difficulties faced by individuals with TBI, but its impact on overall recovery might not be significant, considering the trajectory of the brain injury itself. Notably, the MoCA results indicate that cognitive deficits are more pronounced in PTE patients compared to those with TBI, underscoring the necessity for targeted neuropsychological assessments. Further investigation is essential to explore PTE's broader neuropsychological and psychosocial impacts. These findings advocate for tailored care strategies that address both neuropsychological and psychosocial needs, ensuring comprehensive management of TBI and PTE.
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Widespread wastewater pollution is one of the biggest challenges threatening the ecological health of rivers. It is crucial to identify the toxic changes of effluents after entering urban rivers as well as the toxic substances in the complex chemical mixtures found in these urban rivers. This study used HepG2 cell line for cytotoxicity test to evaluate the ecological impact of effluents on urban rivers. Water samples were collected from the Xingwu River and Yunliang River in Nanjing, China. The bacterial communities in the lower reaches of urban rivers were altered due to the differences in total nitrogen and nitrate nitrogen. The complex chemical mixtures collected in the urban rivers were divided into 10 fractions, >100 chemicals were screened in each fraction. The substances with LC50 < 1000 mg/L were listed as toxic substances, and the number of toxic substances dominated the toxicity of urban rivers. Our study highlights toxicity as a comprehensive indicator for assessing river pollutants and reveals relationship between the number of toxic substance and river toxicity. These findings have direct implications for the monitoring and management of environmental stressors and the protection of aquatic organisms and human health.
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Prenatal diagnosis of congenital heart disease (CHD) relies primarily on fetal echocardiography conducted at mid-gestational age-the sensitivity of which varies among centers and practitioners. An objective method for early diagnosis is needed. Here, we conducted a case-control study recruiting 103 pregnant women with healthy offspring and 104 cases with CHD offspring, including VSD (42/104), ASD (20/104), and other CHD phenotypes. Plasma was collected during the first trimester and proteomic analysis was performed. Principal component analysis revealed considerable differences between the controls and the CHDs. Among the significantly altered proteins, 25 upregulated proteins in CHDs were enriched in amino acid metabolism, extracellular matrix receptor, and actin skeleton regulation, whereas 49 downregulated proteins were enriched in carbohydrate metabolism, cardiac muscle contraction, and cardiomyopathy. The machine learning model reached an area under the curve of 0.964 and was highly accurate in recognizing CHDs. This study provides a highly valuable proteomics resource to better recognize the cause of CHD and has developed a reliable objective method for the early recognition of CHD, facilitating early intervention and better prognosis.
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Cardiopatias Congênitas , Proteoma , Gravidez , Humanos , Feminino , Estudos de Casos e Controles , Proteômica , Cardiopatias Congênitas/diagnóstico , Biomarcadores , Cisplatino , CiclofosfamidaRESUMO
INTRODUCTION: This study aimed to investigate the impact of neuropsychological functions on self-care/self-management in middle-aged individuals with type 2 diabetes (T2DM). AREAS COVERED: A comprehensive literature search was conducted from January 2012 to April 2023 across multiple databases. Ten articles were included in the scoping review, and 3 articles were included in the meta-analysis. The findings consistently indicated an association between reduced neuropsychological functions and poor self-care/self-management in this population. Memory functions, executive functions, and other domains were found to be significantly related to self-care/self-management, including diet management, exercise, blood glucose monitoring, and foot care. EXPERT OPINION: This study highlights the importance of considering neuropsychological factors in understanding and improving diabetes management outcomes. The findings underscore the need for comprehensive neuropsychological assessments and the development of targeted interventions to address specific vulnerable domains. Future research should focus on elucidating underlying mechanisms, addressing methodological inconsistencies, and exploring the effectiveness of interventions targeting neuropsychological impairments. Incorporating technology and personalized approaches into diabetes management can enhance self-care/self-management and clinical outcomes in individuals with T2DM.
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Diabetes Mellitus Tipo 2 , Autogestão , Pessoa de Meia-Idade , Humanos , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/psicologia , Automonitorização da Glicemia , Autocuidado , GlicemiaRESUMO
Executive functions (EF) were the critical neuropsychological functions linked to long-term adaptation. Given the heterogeneous prognosis trajectories of mild traumatic brain jury (mTBI), the mildest TBI may not always be benign in the chronic stage. The present study explored the long-term EF in patients with chronic complicated mTBI and a Glasgow Coma Scale (GCS) score of 15. Fifty patients with complicated mTBI and GCS scores of 15 and 35 control participants were recruited in this study. Medical records were retrospectively analyzed, and neuropsychological assessments and subjective measures examined the neuropsychological functions. Compared with healthy controls, complicated mTBI patients with a GCS score of 15 performed significantly worse on most EF assessments, including longer reaction time (RT) and poor cognitive flexibility and abstract reasoning performances. Patients also reported more EF problems and lower quality of life (QoL) than healthy controls. Females and those with subdural hematoma (SDH) had significantly longer reaction times (RT) on executive attention tests. This study found that complicated mTBI with a GCS score of 15 had incomplete recovery of EF, even in the chronic stage. We suggest that early neuropsychological assessment and rehabilitation should be arranged for such patients.
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BACKGROUND: Because nurses often work in medical environments characterized by high workloads and high levels of stress and pressure, they are particularly vulnerable to workplace burnout and their well-being may suffer. Related studies on burnout, resilience, and well-being have focused primarily on teachers, social workers, and students, with few studies addressing the situation faced by nursing staff. It is important to understand the factors affecting the well-being of nursing staff. PURPOSE: This study explores the status quo and correlations among nursing-staff demographic characteristics, workplace burnout, well-being-related resilience, and the predictive factors of well-being in nurses. METHODS: A cross-sectional, descriptive, correlational research design and purposive sampling were used in this study. Nursing staff who had worked for more than 6 months at a medical center in central Taiwan were recruited as participants, with data from 289 participants collected. A structured questionnaire was used to collect data on demographic characteristics, workplace burnout, resilience, and well-being. RESULTS: The average scores for workplace burnout, resilience, and well-being were 40.40/(0- to 100-point scale), 26.79/(10- to 50-point scale), and 43.25/(24- to 96-point scale), respectively. The result of the regression analysis explained about 51.6% of the variance in well-being. Furthermore, resilience (28.4%), self-perceived health (14.3%), workplace burnout (4.5%), exercise frequency (1.8%), job title (1.2%), interpersonal pressure relief resilience (0.9%), and marital status (0.5%) were other important predictive factors of well-being in the participants. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: Medical institutions should provide appropriate resilience-enhancing countermeasures to reduce workplace burnout as well as pay greater attention to the exercise frequency, self-perceived health, job title, and marital status of their nurses to help them achieve physical, mental, and overall well-being.
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Wastewater discharge is considered to be one of the anthropogenic factors affecting the water quality of urban rivers. The source and composition of wastewater are complex and diverse, and it is difficult to evaluate its effect on water quality and ecological health of receiving waters. Environmental DNA method can determine all species living in waters by examining DNA sequences, reflecting the impact of water quality changes on aquatic systems. In this study, water samples from two urban rivers were collected in dry and wet seasons, and the composition of pollutants was investigated by nontarget screening. Based on the pollutant composition, compound toxicity prediction and concentration addition model were used to predict the toxicity changes of pollutants in the urban rivers. More than 1500 suspect organic pollutants were nontarget screened, and silafluofen was found to be a major toxicity contributor. Environmental DNA analysis was combined with water quality measure and pollutant toxicity prediction to reveal the effects of pollutants from different sources on aquatic ecosystems. Fish diversity was negatively correlated with the mixed toxicity of organic pollutants, suggesting potential ecological risk in these two urban rivers. Our study developed a water quality assessment method based on pollutant composition and toxicity, and the potential risk of nonpoint source pollutants on aquatic ecosystems should not be neglected.
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DNA Ambiental , Poluentes Ambientais , Poluição Difusa , Animais , Ecossistema , Rios , Águas ResiduáriasRESUMO
BACKGROUND: Phthalates exposure might affect children's intelligence development. This study aimed to determine (1) whether sex and age affect cognitive function and (2) whether sex differences in cognitive performance are wider with higher phthalate concentrations. METHODS: Data were collected from PubMed (1998-2022), PROQUEST (1997-2022), and SpringerLink (1995-2022). The study followed the PRISMA process. The included articles were followed by PECO framework. The GRADE applied to assess the certainty of evidence. Of 2422 articles obtained, nine were selected using inclusion criteria. The random-effects model was used to estimate the pooled effects. RESULTS: Our meta-regression indicated a significant difference between sex differences with age at phthalate concentration assessment (ß = -0.25; 95% CI = -0.47, -0.03) and MEHP concentration (ß = -0.20; 95% CI = -0.37, -0.03). CONCLUSIONS: The limitation of the current article is it only provides information on intelligence level rather than other aspects of cognitive function. Thus, the sequelae of phthalate exposure on attention and executive function are still unclear. Our analysis shows significant difference between sex differences in cognitive function scores associated with age at phthalate concentration assessment. Girls might be more resilient in cognitive function at a younger age or during lower concentrations of phthalates metabolites. IMPACT: This is the first meta-analysis to evaluate the pooled estimates of sex differences in objective cognitive functions among children with phthalate exposure. The female might be a protective factor when exposed to toxic plasticizers while the concentration is low. This study captures the possible role of sex in cognitive functioning and plasticizer exposure through a meta-analysis of children's sex, cognitive scores, and plasticizer exposure.
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Poluentes Ambientais , Ácidos Ftálicos , Humanos , Criança , Masculino , Feminino , Plastificantes/análise , Caracteres Sexuais , Cognição , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/análise , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidadeRESUMO
OBJECTIVES: To date, the research on the prognosis of the neuropsychological function of patients with post-traumatic seizure (PTE) is sparse. This study aimed to systematically map the literature's extent, range, and characteristics regarding PTE and neuropsychological impairments. METHODS: A systematic literature search was conducted in CINAHL, Cochrane, Embase, Medline, PubMed, Scopus, Web of Science, and ScienceDirect databases. The search terms were related to PTE and neuropsychological impairments. RESULTS: This scoping review included seven studies, two of which examined the impact of PTE on neuropsychological outcomes. Among the three studies that used neuropsychological assessments, attention/concentration, and memory were the most frequently assessed domains. Only one study reported a significant difference between PTE and non-PTE patients. The cognitive rating scale findings in the other four studies were similar, indicating that patients with PTE performed worse than those without PTE. CONCLUSIONS: The results of this review suggest that patients with PTE may have neuropsychological function impairments. More attention needs to be paid to older patients and those with higher brain injury and seizure severity. Additional investigation is necessary to determine the clinical characteristics of TBI and PTE and elucidate the relations between PTE and specific neuropsychological domains.
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Lesões Encefálicas Traumáticas , Lesões Encefálicas , Epilepsia Pós-Traumática , Humanos , Convulsões , PacientesRESUMO
Utilisation of dissolved organic phosphorus (DOP) by marine microbes as an alternative phosphorus (P) source when phosphate is scarce can help sustain non-Redfieldian carbon:nitrogen:phosphorus ratios and efficient ocean carbon export. However, global spatial patterns and rates of microbial DOP utilisation are poorly investigated. Alkaline phosphatase (AP) is an important enzyme group that facilitates the remineralisation of DOP to phosphate and thus its activity is a good proxy for DOP-utilisation, particularly in P-stressed regions. We present a Global Alkaline Phosphatase Activity Dataset (GAPAD) with 4083 measurements collected from 79 published manuscripts and one database. Measurements are organised into four groups based on substrate and further subdivided into seven size fractions based on filtration pore size. The dataset is globally distributed and covers major oceanic regions, with most measurements collected in the upper 20 m of low-latitude oceanic regions during summer since 1997. This dataset can help support future studies assessing global ocean P supply from DOP utilisation and provide a useful data reference for both field investigations and modelling activities.
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OBJECTIVES: Daam1 (Dishevelled-associated activator of morphogenesis 1) is a Wnt/PCP signaling protein that engages in cytoskeleton reorganization and is abnormally activated in certain tumors. Daam1 is closely related to cancer metastasis, which is expected to become a target for cancer treatment. However, the natural small molecules targeting Daam1 have not been identified. MATERIALS AND METHODS: We screened several natural small molecules that may bind to Daam1 by Sybyl molecular simulation docking technique. As a first-line drug for the treatment of small cell lung cancer, etoposide was chosen for further investigation. Next, we used Micro Scale Thermophoresis (MST) to verify the interaction of etoposide and Daam1. Small cell lung cancer H446 cells and breast cancer MCF-7 cells were treated with etoposide and subjected to Western blotting to measure the Daam1 expression. The effect of etoposide on cell proliferation was determined by CCK-8 assay in vitro and by a tumor-bearing mouse model in vivo. Wound healing assay and Boyden chamber assay were used to evaluate the role of etoposide in the migration and invasion ability of tumor cells. The effect of etoposide on the microfilament assembly was visualized by immunofluorescence staining with phalloidine. Finally, the possible mechanism of down-regulation of Daam1 expression after etoposide-induced small cell lung cancer cells was detected by a half-life experiment and immunofluorescence staining with lysosomal marker LAMP1. RESULTS: Sybyl molecular modeling docking technique was performed to screen a natural chemical library for molecules that bound to the FH2 domain of Daam1 and found etoposide was virtually interacted with Daam1. MST validated etoposide directly bound to the FH2 domain of Daam1. Etoposide significantly down-regulated the expression of Daam1 in small cell lung cancer H446 cells and breast cancer MCF-7 cells. Moreover, 270 µmol/L etoposide largely inhibited the proliferation, migration, and invasion of H446 cells and MCF-7 cells. Immunofluorescence staining experiments revealed that etoposide induced the disassembly of microfilaments in H446 cells and MCF-7 cells, which were rescued by Daam1 overexpression. In nude mice transplanted with H446 cells, 5, 10, 20 mg/kg etoposide (drug/weight) injected via tail vein largely retarded the proliferation of subcutaneous tumors. Etoposide induced Daam1 to shorten its half-life and enter the lysosome degradation pathway, and eventually leading to the downregulation of Daam1 expression. CONCLUSIONS: Etoposide is a novel natural small molecule targeting Daam1. Etoposide inhibits the proliferation, migration and invasion of small cell lung cancer cells and breast cancer cells, and also suppresses tumor proliferation of small cell lung cancer in vivo.
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Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Camundongos , Proteínas dos Microfilamentos/metabolismo , Etoposídeo/farmacologia , Etoposídeo/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Proteínas rho de Ligação ao GTP/metabolismo , Camundongos Nus , Proteínas Wnt/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Proliferação de Células , Movimento Celular , Linhagem Celular TumoralRESUMO
BACKGROUND: Most diabetic patients suffer from chronic diseases affecting their self-management status. This study aims to explore the relationship between the CoC and the self-management of patients with Type 2 Diabetes Mellitus (T2DM) and analyze the predictive factors affecting their self-management. METHODS: Structured questionnaires were used for data collection. Convenient sampling was adopted to recruit inpatients diagnosed with T2DM in the endocrine ward of a medical hospital in central Taiwan. RESULTS: A total of 160 patients were recruited. The average age of the patients is 66.60 ± 14.57 years old. Among the four dimensions of the self-management scale, the average score of the problem-solving dimension was the highest, and that of the self-monitoring of blood glucose was the lowest. The analysis results showed that the overall regression model could explain 20.7% of the total variance in self-management. CONCLUSIONS: Healthcare providers should attach importance to the CoC of T2DM patients and encourage patients to maintain good interaction with healthcare providers during their hospitalization. It is recommended to strengthen CoC for patients with diabetes who are single or with low educational levels in clinical practice to enhance their blood glucose control and improve diabetes self-management.
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Objective. Neurofeedback can reduce ADHD symptoms; however, current programs are relatively long, with fewer concerns about executive function (EF). The present study aimed to investigate a 20-hour combined computerized training neurofeedback program. Methods. Fifty ADHD children were randomly assigned to either the experimental group (EXP) or the wait-list control group (CON), who took training after the post-tests. The EF measures were the Tower of London (ToL), Wisconsin Card Sorting Test (WCST), and Comprehensive Nonverbal Attention Test (CNAT). SNAP-IV and questionnaires reported by parents constituted the behavioral measures. Two-way repeated-measures ANOVA and bootstrapping dependent t-tests were also used. Results. The F-tests revealed the interaction effects on ADHD symptoms and math scores. The EXP had increased the ToL scores, decreased the error and perseverative error rates on WCST, as well as the dysexecutive index on CNAT in the t-test. Conclusions. The training effects were related to behavioral symptoms and functions, EFs, and generalized achievement performances. We suggest that future studies could apply to different patients and examine the maintenance of the program.
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Transtorno do Deficit de Atenção com Hiperatividade , Neurorretroalimentação , Atenção , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Criança , Eletroencefalografia , Função Executiva , Humanos , Neurorretroalimentação/métodosRESUMO
Persistent infections caused by Staphylococcus aureus biofilms pose a major threat to global public health. 10-Hydroxy-2-decenoic acid (10-HDA), a main fatty acid in royal jelly, has been shown to possess various biological activities. The purpose of this study was to explore the effects of 10-HDA on the biofilms and virulence of S. aureus and its potential molecular mechanism. Quantitative crystal violet staining indicated that 10-HDA significantly reduced the biofilm biomass at sub-minimum inhibitory concentration (MIC) levels (1/32MIC to 1/2MIC). Scanning electron microscope (SEM) observations demonstrated that 10-HDA inhibited the secretion of extracellular polymeric substances, decreased bacterial adhesion and aggregation, and disrupted biofilm architecture. Moreover, 10-HDA could significantly decrease the biofilm viability and effectively eradicated the mature biofilms. It was also found that the hemolytic activity of S. aureus was significantly inhibited by 10-HDA. qRT-PCR analyses revealed that the expressions of global regulators sarA, agrA, and α-hemolysin gene hla were downregulated by 10-HDA. These results indicate that 10-HDA could be used as a potential natural antimicrobial agent to control the biofilm formation and virulence of S. aureus.
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Staphylococcus aureusRESUMO
Bacterioplankton community is the major engine that drives the biogeochemical cycling of various nutrient and essential elements in the coastal ecosystem. Unraveling the mechanisms governing the succession of such complex bacterioplankton communities in dynamic environment is a challenging issue in environmental science. In this study, we investigated the diversity patterns and succession mechanisms of both free-living and particle-attached bacterioplankton communities that have been exposed to low oxygen and typhoon Lekima. The community evenness was the lowest in August when the temperature was high and dissolved oxygen was low. Similar patterns in community succession were observed for free-living and particle-attached bacterioplankton community after the passing through of typhoon Lekima. Both the free-living and particle-attached bacterioplankton communities in the surface and bottom water columns were strongly affected by geo-environmental factors, among which temperature was the common factor, suggesting that the metabolic theory of ecology also underlie the dynamic patterns of bacterioplankton communities. Although the surface and bottom bacterioplankton compositions were initially different taxonomically and shaped by different environmental conditions, they followed a similar succession pattern over the sampling months. Temperature, dissolved inorganic carbon and dissolved inorganic phosphorus were the major factors associated with the variations of surface bacterioplankton ASVs. Time-decay relationship, in which community similarity decreases with increasing time interval, was clearly observed. Such pattern shall be attributed to the combined effects of time and the changing environmental factors over the sampling months, rather than time alone. Integrating multiple lines of evidences, we demonstrated that determinism governed the succession of both free-living and particle-attached bacterioplankton communities in the coastal maricultural ecosystem, with higher stochastic ratio in habitable months (i.e. fall). This study is expected to provide valuable mechanistic insights into the succession of disturbed complex bacterioplankton communities.
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Organismos Aquáticos , Ecossistema , OxigênioRESUMO
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases in wheat worldwide. Planting resistant varieties is the most economical, effective, and environment-friendly measure to control wheat stripe rust. Changfeng 75, a Chinese winter wheat variety, shows high stripe rust resistance in both seedling and adult-plant stages. The seedling tests of F1, F2, and F2:3 populations derived from Mingxian 169/Changfeng 75 inoculated with Chinese predominant Pst race CYR34 showed that the stripe rust resistance of Changfeng 75 was controlled by a single recessive gene. The locus was temporarily designated as YrCf75. Bulked segregant analysis (BSA) combined with the wheat 660K single-nucleotide polymorphism (SNP) array and bulked segregant RNA-sequencing indicated that the proportion of polymorphic SNPs on wheat chromosome 2A was the highest, which suggested that YrCf75 was likely located on chromosome 2A. Two hundred and twenty-five Kompetitive allele-specific PCR (KASP) and 75 simple sequence repeat (SSR) markers on chromosome 2A were used to map YrCf75 using the BSA approach. Linkage analysis indicated that 31 KASP markers and one SSR marker were linked to YrCf75, and the genetic distances of the two closest flanking KASP markers, AX-1110060462 and AX-111004763, were 1.2 and 2.7 cM, respectively. YrCf75 was located on wheat chromosome 2AL. The molecular detection, resistance specificity, and chromosome location showed that YrCf75 is likely a new gene that is different from the known stripe rust resistance genes (Yr1 and Yr32) on wheat chromosome 2AL.
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Basidiomycota , Resistência à Doença , Basidiomycota/genética , Mapeamento Cromossômico , Resistência à Doença/genética , Genes de Plantas , Genes Recessivos , Genótipo , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único/genética , RNA , Triticum/genéticaRESUMO
Arsenic (As) and disinfection by-products are important health risk factors in the water environment. However, their combined effects on different cell populations in the liver are not well known. Here, zebrafish were exposed to 100 µg/L As, 300 µg/L 2,2-dichloroacetamide (DCAcAm), and their combination for 23 days. Then transcriptome profiles of cell populations in zebrafish liver were analyzed by single-cell RNA sequencing (scRNA-seq). A total of 13,563 cells were obtained, which were identified as hepatocytes, hepatic duct cells, endothelial cells and macrophages. Hepatocytes were the main target cell subtype of As and DCAcAm exposures. DCAcAm exposure induced higher toxicity in male hepatocytes, which specifically changed amino acid metabolism, response to hormone and cofactor metabolism. However, As exposure caused higher toxicity in female hepatocytes, which altered lipid metabolism, carbon metabolism, and peroxisome. Combined exposure to As and DCAcAm decreased toxicities in hepatocytes compared to each one alone. Female hepatocytes had higher tolerance to co-exposure of As and DCAcAm than male hepatocytes. Further, combined exposure to As and DCAcAm induced functional changes in macrophages similar to As alone groups, which mainly altered the transfer of sterol and cholesterol. Hepatic duct cells and endothelial cells were not influenced by exposures to As and DCAcAm. This study for the first time highlights the cell-specific combined responses of As and DCAcAm in zebrafish liver, which provide useful information for their health risk assessment in a co-exposure environment.
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Acetamidas/toxicidade , Arsênio , Poluentes Químicos da Água/toxicidade , Animais , Arsênio/toxicidade , Células Endoteliais , Feminino , Fígado , Masculino , Peixe-ZebraRESUMO
Children with attention deficit hyperactivity disorder (ADHD) have high theta and low beta activity in the frontal lobe. The higher the theta/beta ratio, the lower the level of central nervous system (CNS) cortical arousal. However, there is seldom evidence between electroencephalograms (EEGs) and the patient's intentionality to regulate the cortical activity of executive attention tasks. We investigated whether children with ADHD intended to improve their performance in executive attention tasks and whether that increased their brain activity. Fifty-one children with ADHD (ADHD) and 51 typical developing (TD) children were investigated using focused attention (FA) and search attention (SA) tasks and a simultaneous EEG. The children were then regrouped as faster (ADHD-F, TD-F) and slower (ADHD-S, TD-S) depending on reaction time (RT). Quantitative EEGs of frontal lobe theta and beta activity at frontal F3, F4, and Fz were used. Twenty-eight (54.9%) ADHD children were regrouped as ADHD-S and 14 (27.5%) as TD-S. The ADHD-S group, however, had poorer FA and SA performance than the other 3 groups did: fewer correct answers, more frequent impulsive and missing errors, and higher RT variations. There were no significant differences in theta activity, but the TD-S group had higher beta activity than the ADHD-S group did. We conclude that the ADHD-F and ADHD-S groups had different attention processes. beta activity did not increase in the ADHD-S group, and their executive attention performance in the FA and SA tests was poor. It seems ADHD-S had poor meta-intention function. The frontal beta activity might be a feasible training target of neurofeedback in ADHD-S patients.
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Transtorno do Deficit de Atenção com Hiperatividade , Neurorretroalimentação , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Eletroencefalografia , Humanos , Intenção , Tempo de ReaçãoRESUMO
To improve the foaming behavior of a common linear polypropylene (PP) resin, polycarbonate (PC) was blended with PP, and three different grafted polymers were used as the compatibilizers. The solid and foamed samples of the PP/PC 3:1 blend with different compatibilizers were first fabricated by melt extrusion followed by injection molding (IM) with and without a blowing agent. The mechanical properties, thermal features, morphological structure, and relative rheological characterizations of these samples were studied using a tensile test, dynamic mechanical analyzer (DMA), scanning electron microscope (SEM), and torque rheometer. It can be found from the experimental results that the influence of the compatibility between the PP and PC phases on the foaming behavior of PP/PC blends is substantial. The results suggest that PC coupling with an appropriate compatibilizer is a potential method to improve the foamability of PP resin. The comprehensive effect of PC and a suitable compatibilizer on the foamability of PP can be attributed to two possible mechanisms, i.e., the partial compatibility between phases that facilitates cell nucleation and the improved gas-melt viscosity that helps to form a fine foaming structure.
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Poly(cyclohexylene dimethylene cyclohexanedicarboxylate) (PCCE) is a kind of copolyester polymer with excellent toughness and outstanding flexibility. However, the opacity caused by crystallization limits the widespread application of PCCE in products that have transparency requirements. The effects of 1,3:2,4-Di-p-methylbenzylidene sorbitol (MDBS) on the crystallization behavior, transparency, and mechanical properties of a PCCE melt were investigated via differential scanning calorimetry (DSC), spectrophotometry, and tensile testing. The results suggest that the transparency and mechanical properties of PCCE drastically improve and that its crystallization behaviors are obviously influenced by the addition of MDBS. PCCE with 0.6 wt% MDBS was then selected as a representative sample, and its thermal behavior and crystal morphology were further investigated by DSC, hot-staged polarizing microscopy (HSPLM), and scanning electron microscopy (SEM). The quantitative results suggest that, compared to neat PCCE resin, PCCE/MDBS has a lower isothermal and nonisothermal crystallization activation energy, which indicates a rapid crystallization process. The results also show that, compared to the pure PCCE melt, the PCCE/MDBS melt experiences a greater increase in the number of crystals and a greater decrease in the crystal size during cooling. The acceleration of the crystallization process and reduction in crystal size can be both attributed to the nucleation effect of the MDBS. In conclusion, because the addition of the nucleating agent improves the transparency and tensile properties of PCCE by adjusting and controlling its thermal and crystallization behaviors, the proposed technique of using a compounding nucleating agent to control crystallization is therefore suitable for PCCE.