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A high resolution inverse synthetic aperture radar (ISAR) technique is presented using modified Doppler history based motion compensation. To this purpose, a novel wideband ISAR system is developed that accommodates parametric processing over extended aperture length. The proposed method is derived from an ISAR-to-SAR approach that makes use of high resolution spotlight SAR and sub-aperture recombination. It is dedicated to wide aperture ISAR imaging and exhibits robust performance against unstable targets having non-linear motions. We demonstrate that the Doppler histories of the full aperture ISAR echoes from disturbed targets are efficiently retrieved with good fitting models. Experiments have been conducted on real aircraft targets and the feasibility of the full aperture ISAR processing is verified through the acquisition of high resolution ISAR imagery.
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We assessed empathy in medical residents, including factors modifying empathy and the relationship between empathy and burnout. Participants (n = 317 residents, response rate = 42%) from 4 university hospitals completed a socio-demographic questionnaire, the Jefferson Scale of Empathy (Health Professional version, Korean edition), and the Maslach Burnout Inventory (MBI). Participants were classified by medical specialty: "people-oriented specialty" (POS group) or "technology-oriented specialty" (TOS group), with more women in the POS than in the TOS group, χ(2) = 14.12, P < 0.001. Being female, married, and having children were factors related to higher empathy (gender, t = -2.129, P = 0.034; marriage, t = -2.078, P = 0.038; children, t = 2.86, P = 0.005). Within specialty group, POS residents showed higher empathy scores in the fourth as compared to the first year, F = 3.166, P = 0.026. Comparing POS and TOS groups by year, fourth year POS residents had significantly higher scores than did fourth year TOS residents, t = 3.349, P = 0.002. There were negative correlations between empathy scores and 2 MBI subscales, emotional exhaustion (EE) and depersonalization (DP). Additionally, first year POS residents had higher DP scores than did first year TOS residents, t = 2.183, P = 0.031. We suggest that factors important for empathy are type of medical specialty, marriage, siblings, and children. Burnout state may be related to decreasing empathy.
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Esgotamento Profissional , Empatia , Médicos/psicologia , Adulto , Criança , Educação Infantil , Demografia , Despersonalização , Feminino , Hospitais Universitários , Humanos , Internato e Residência , Masculino , Casamento , Fatores Sexuais , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: The aim of the current study was to investigate the effect of methylphenidate-osmotic release oral delivery system (MPH-OROS) treatment on parenting stress in parents of children and adolescents with attention-deficit/hyperactivity disorder (ADHD). METHODS: Four hundred and ninety-five children and adolescents (391 boys and 104 girls), aged 7 to 18 years who met the Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria for ADHD, were recruited at 48 psychiatric outpatient clinics across South Korea. Children's symptoms, parenting stress, and parental depression were assessed at baseline, week 4, and week 8 of MPH-OROS treatment using the Korean version of the DuPaul's ADHD Rating Scale (ARS), the Beck's Depression Inventory (BDI), and the Parenting Stress Index, Short Form (PSI-SF). RESULTS: We found significantly decreased scores of ARS, parental BDI, and PSI-SF from baseline to week 4 and from week 4 to week 8. Also, there were positive correlations among baseline PSI-SF, ARS, and BDI scores. The changes in BDI and ARS scores were significantly associated with the PSI score changes, accounting for 20.1% and 10.0%, respectively. CONCLUSIONS: We suggest that the increased parenting stress and depression in parents of children and adolescents with ADHD can be improved following the treatment with MPH-OROS.
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Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Estimulantes do Sistema Nervoso Central/uso terapêutico , Metilfenidato/uso terapêutico , Poder Familiar/psicologia , Adolescente , Estimulantes do Sistema Nervoso Central/administração & dosagem , Criança , Preparações de Ação Retardada , Feminino , Seguimentos , Humanos , Masculino , Metilfenidato/administração & dosagem , Pais , República da Coreia , Estresse Psicológico/etiologia , Estresse Psicológico/psicologiaRESUMO
12CaO x 7Al2O3, insulator (C12A7) doped indium tin oxide (ITO) (ITO:C12A7) films were fabricated using a radio frequency magnetron co-sputtering system with ITO and C12A7 targets. The qualitative and quantitative properties of ITO:C12A7 films, as a function of C12A7 concentration, were examined via X-ray photoemission spectroscopy and synchrotron X-ray scattering as well as by conducting atomic force microscopy. The work function of ITO:C12A7 (1.3%) films of approximately 2.8 eV obtained by high resolution photoemission spectroscopy measurements make them a reasonable cathode for top-emission organic light-emitting diodes.
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Óxido de Alumínio/química , Eletrodos , Iluminação/instrumentação , Nanoestruturas/química , Compostos Orgânicos/química , Semicondutores , Compostos de Estanho/química , Compostos de Cálcio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Nanoestruturas/ultraestrutura , Óxidos/química , Tamanho da Partícula , RefratometriaRESUMO
Silicon (Si) is considered to be one of the most promising anode candidates for next-generation lithium-ion batteries because of its high theoretical specific capacity and low discharge potential. However, its poor cyclability, caused by tremendous volume change during cycling, prevents commercial use of the Si anode. Herein, we demonstrate a high-performance Si anode produced via covalent bond formation between a commercially available Si nanopowder and a linear polymeric binder through an esterification reaction. For efficient ester bonding, polyacrylic acid, composed of -COOH groups, is selected as the binder, Si is treated with piranha solution to produce abundant -OH groups on its surface, and sodium hypophosphite is employed as a catalyst. The as-fabricated electrode exhibits excellent high rate capability and long cycle stability, delivering a high capacity of 1500 mA h g-1 after 500 cycles at a high current density of 1000 mA g-1 by effectively restraining the susceptible sliding of the binder, stabilizing the solid electrolyte interface layer, preventing the electrode delamination, and suppressing the Si aggregation. Furthermore, a full cell is fabricated with as-fabricated Si as an anode and commercially available LiNi0.6Mn0.2Co0.2O2 as a cathode, and its electrochemical properties are investigated for the possibility of practical use.
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A new P2-type Na0.7(Ni0.6Co0.2Mn0.2)O2 was prepared via co-precipitation and its electrochemical properties as a cathode for sodium ion batteries were compared with those of O3-type Na(Ni0.6Co0.2Mn0.2)O2, focusing on phase stability and cycling performance. The P2-type delivered a high capacity of 108 mA h g-1 after 300 cycles at 2C.
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Neurofeedback (NF) has been identified as a "possibly efficacious" treatment in current evidence-based reviews; therefore, more research is needed to determine its effects. The current study examined the potential additive effect of NF for children diagnosed with ADHD beginning a medication trial first. Thirty-six children (6-12 years) with a DSM-IV-TR diagnosis of ADHD were randomly assigned to an NF with medication (NF condition) or a medication only condition. Children in the NF group attended 20 twice-weekly sessions. Outcome measures included individual cognitive performance scores (ADS, K-WISC-III), ADHD rating scores completed by their parents (ARS, CRS) and brainwave indices of left and right hemispheres before and after NF treatment. Significant additive treatment effect in any of the symptom variables was found and a reduction of theta waves in both the right and left hemispheres was recorded in NF condition participants. However our randomized controlled study could not demonstrate superior effects of combined NF on intelligent functioning compared to the medication treatment only. This study suggested any possible evidence of positive and additive treatment effects of NF on brainwaves and ADHD symptomatology.
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Transtorno do Deficit de Atenção com Hiperatividade/terapia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Neurorretroalimentação/métodos , Avaliação de Resultados em Cuidados de Saúde , Ritmo Teta/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Terapia Combinada , Feminino , Humanos , MasculinoRESUMO
Constitutive activation of the telomerase is a key step in the development of human cancers. Interferon-gamma (IFN-gamma) signaling induces growth arrest in many tumors through multiple regulatory mechanisms. In this study, we show that IFN-gamma signaling represses telomerase activity and human telomerase reverse transcriptase (hTERT) transcription, and suggest that this signaling is mediated by IRF-1. Ectopic expression of IRF-1 attenuated hTERT promoter activity. Murine embryonic fibroblasts (MEFs) genetically deficient in IRF-1 (IRF-1(-/-)) showed an elevated level (>15 times) of hTERT promoter activity as compared to the hTERT promoter activity of wild-type MEFs. The telomerase activity and hTERT expression in IRF-1(-/-) MEFs were downregulated by IRF-1 transfection. Interestingly, less extent of telomerase repression was observed in HPV E6 and E7 negative, p53 mutant HT-3 cells than in HPV 18 E6 and E7 positive HeLa cells (intact p53). These findings provide evidence that IRF-1 is a potential mediator of IFN-gamma-induced attenuation of telomerase activity and hTERT expression.
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Proteínas de Ligação a DNA/metabolismo , Interferon gama/metabolismo , Fosfoproteínas/metabolismo , Telomerase/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Feminino , Fibroblastos , Fase G1/genética , Células HeLa/efeitos dos fármacos , Humanos , Fator Regulador 1 de Interferon , Interferon gama/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Fosfoproteínas/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais , Telomerase/genética , Transcrição Gênica , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/genéticaRESUMO
The production of nanofibrous PLA/HA composite scaffolds is described. The morphological, mechanical, surface, and thermal properties of the composites were extensively investigated. The results show that the mixture of PLA and HA formed smooth nanofibers without lumps. The incorporation of HA increased the mechanical strength of the nanofibers and changed the morphology, increasing the mean fiber diameter and pore size. Surface and internal properties confirmed that HA was homogeneously distributed inside the nanofibers and oriented towards their surface. The nanofiber composites allowed the adhesion and proliferation of pre-osteoblasts for up to 3 weeks.
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Biomimética , Biotecnologia/métodos , Técnicas de Cultura de Células/instrumentação , Durapatita/química , Nanopartículas/química , Osteoblastos/citologia , Osteoblastos/metabolismo , Regeneração , Engenharia Tecidual/métodos , Células 3T3 , Animais , Técnicas de Cultura de Células/métodos , Camundongos , Modelos Biológicos , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Difração de Raios XRESUMO
The treatment of pathologic aerophagia has rarely been discussed in the literature. In this retrospective study, the authors investigated the effects of clonazepam on the management of pathologic childhood aerophagia (PCA) with psychological stresses (PS), but not with mental retardation. Data from 22 consecutive PCA patients with PS (aged 2 to 10 yr), who had been followed up for over 1 yr, were reviewed. On the basis of videolaryngoscopic views, the authors observed that the pathology of aerophagia was the result of reflex-induced swallowing with paroxysmal openings of the upper esophageal sphincter due to unknown factors and also observed that these reflex-induced openings were subsided after intravenous low dose benzodiazepine administration. Hence, clonazepam was administered to treat paroxysmal openings in these PCA patients with PS. Remission positivity was defined as symptom-free for a consecutive 1 month within 6 months of treatment. The results of treatment in 22 PCA patients with PS were analyzed. A remission positive state was documented in 14.3% of PCA patients managed by reassurance, and in 66.7% of PCA patients treated with clonazepam (p=0.032). Thus, clonazepam may produce positive results in PCA with PS. Future studies by randomized and placebo-controlled trials are needed to confirm the favorable effect of clonazepam in PCA.
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Aerofagia/complicações , Aerofagia/prevenção & controle , Clonazepam/administração & dosagem , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico , Anticonvulsivantes/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Injeções Intravenosas , Masculino , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Within a polymer film, free-volume elements such as pores and channels typically have a wide range of sizes and topologies. This broad range of free-volume element sizes compromises a polymer's ability to perform molecular separations. We demonstrated free-volume structures in dense vitreous polymers that enable outstanding molecular and ionic transport and separation performance that surpasses the limits of conventional polymers. The unusual microstructure in these materials can be systematically tailored by thermally driven segment rearrangement. Free-volume topologies can be tailored by controlling the degree of rearrangement, flexibility of the original chain, and judicious inclusion of small templating molecules. This rational tailoring of free-volume element architecture provides a route for preparing high-performance polymers for molecular-scale separations.
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OBJECTIVE: This study investigated the early recognition and diagnosis of pathologic childhood aerophagia to avoid unnecessary diagnostic approaches and serious complications. METHODS: Between 1995 and 2003, data from 42 consecutive patients with pathologic childhood aerophagia, aged 2 to 16 years, were reviewed. An esophageal air sign was defined as an abnormal air shadow on the proximal esophagus adjacent to the trachea on a full-inflated chest radiograph. RESULTS: Of the 42 patients, the chief complaints were abdominal distention (52.4%), recurrent abdominal pain syndrome (21.4%), chronic diarrhea (11.9%), acute abdominal pain (7.1%) and others (7.2%). Mean symptom duration before diagnosis was 10.6 months (range, 1 to 60 months), and it exceeded 12 months for 16 (38.1%) patients. The clinical features common to all patients were abdominal distention that increased progressively during the day, increased flatus on sleep, increased bowel sound on auscultation and an air-distended stomach with increased gas in the small and large bowel by radiography. Visible or audible air swallowing (26.2%) and repetitive belching (9.5%) were also noted. Esophageal air sign was observed in 76.2% of the patients and in 9.7% of the controls (P=0.0001). The subgroups of pathologic childhood aerophagia divided by underlying associations were pathologic childhood aerophagia without severe mental retardation (76.2%), which consisted of psychological stresses and uncertain condition, and pathologic childhood aerophagia with severe mental retardation (23.8%). CONCLUSIONS: The common manifestations of pathologic childhood aerophagia may be its essential diagnostic criteria, and esophageal air sign may be useful for the early recognition of pathologic childhood aerophagia. Our observations show that the diagnostic clinical profiles suggested by Rome II criteria should be detailed and made clearer if they are to serve as diagnostic criteria for pathologic childhood aerophagia.
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Aerofagia/diagnóstico , Aerofagia/patologia , Dor Abdominal/etiologia , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Eructação/etiologia , Feminino , Flatulência/etiologia , Fluoroscopia , Humanos , Masculino , Radiografia Abdominal , Estudos RetrospectivosRESUMO
1. The effects of (-)-epigallocatechin gallate (EGCG), a green tea polyphenol, on glutamate-induced increases in intracellular Ca2+ concentrations ([Ca2+]i) and cytotoxicity in PC12 cells were investigated. 2. Changes in [Ca2+]i were measured using Fura-2/AM calcium indicator dye and cellular viabilities were determined by a viable cell count and a 3-(4,4-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assay. 3. Glutamate increased [Ca2+]i in PC12 cells in a dose-dependent manner. (-)-Epigallocatechin gallate attenuated this glutamate (30 mmol/L)-induced [Ca2+]i increase and EGCG (50 micromol/L) increased the viability of PC12 cells against glutamate-induced cytotoxicity. The EGCG effect was also found to be independent of its general anti-oxidant mechanism. In contrast, EGCG directly suppressed both N-methyl-D-aspartate (50 mmol/L)- and kainate (20 mmol/L)-mediated Ca2+ influx, but not metabotropic receptor-mediated Ca2+ release. 4. These results suggest that EGCG reduces the glutamate-induced [Ca2+]i increase by attenuating ionotropic Ca2+ influx and that this promotes the viability of PC12 cells.