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1.
Acta Psychol (Amst) ; 226: 103573, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35338832

RESUMO

BACKGROUND: There are limited studies on the associations among parenting style, postpartum depression, and mother-infant bonding. OBJECTIVE: The aims of this study are investigating how the parenting style of maternal grandparents predicted the mothers' bonding with their infants. The mediating roles of postpartum depression were also explored. PARTICIPANTS AND SETTING: A community sample of 227 postpartum women participated in this study. The participants primarily consisted of women who gave birth within six months (89.9%). METHODS: A cross-sectional and convenient sampling strategy was applied. Instruments were Parental Bonding Instrument, Edinburgh Postnatal Depression Scale, Postpartum Bonding Questionnaire, and Background Form. RESULTS: In the young infant group (i.e. mothers with infants not older than three months), the results indicated that maternal protection could predict "impaired bonding" (ß = 0.20, p < .05). This prediction was mediated by postpartum depression (ß = 0.32, p < .001). In the older infant group, paternal and maternal care could directly predict "rejection and anger" (ß = -0.20, -0.22 respectively, p < .05). Maternal protection could predict three bonding factors (ß = 0.25-0.29, p < .05, 0.01). Postpartum depression acted as total mediator for "impaired bonding"(ß = 0.45, p <. 001), and acted as partial mediators in "rejection and anger" and "anxiety about care" (ß = 0.45, 0.28, ps < .001, .01). CONCLUSIONS: Perceived parenting style (especially maternal protection) has impacts on adverse mother-infant bonding. Furthermore, the impact is more prominent on mothers of older infants. "Rejection and anger" could be the most vulnerable bonding factor affected by parenting style. Since postpartum depression mediates the predictions, interventions could concurrently address maternal parenting style and postpartum depression.


Assuntos
Depressão Pós-Parto , Mães , Estudos Transversais , Feminino , Humanos , Lactente , Relações Mãe-Filho , Apego ao Objeto , Poder Familiar , Inquéritos e Questionários
2.
Ann Otol Rhinol Laryngol ; 119(5): 336-41, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20524580

RESUMO

OBJECTIVES: Nasopharyngeal branchial cysts (NBCs) are derived from a remnant of the branchial apparatus and originate from the lateral wall of the nasopharynx. Total excision of these cysts was the standard treatment in the past. We present a simpler and less invasive approach for NBC treatment, involving marsupialization, and report on its effectiveness and advantages. METHODS: The surgical approach was transoral. A circular incision 2 to 3 cm in diameter was made directly through the inferior wall of the cyst. After the NBC was drained, its opening was widened with scissors. A disk of oropharyngeal mucosa and the connecting inferior wall of the cyst were excised together. The cut edges of the inner lining of the cyst and the oropharyngeal mucosa were approximated with sutures. RESULTS: All 4 patients were female. One patient was observed because of poor cardiovascular health. The 3 patients who were managed surgically underwent successful transoral cyst marsupialization. The mean follow-up period was 21 months (range, 8 to 40 months). No obvious postoperative complication or recurrence was noted. CONCLUSIONS: Transoral marsupialization is a simple, effective, and less invasive method for treatment of NBCs.


Assuntos
Branquioma/cirurgia , Nasofaringe/anormalidades , Adulto , Idoso , Branquioma/diagnóstico , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos
3.
Nanotechnology ; 20(30): 305303, 2009 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-19581689

RESUMO

A new method for the fabrication of periodic CNT arrays was developed in this study, which involves the use of the inverse nano-sphere lithography (INSL) process. Mo of a honeycomb pattern, acting as a catalyst-poisoning layer, was produced by the nano-sphere lithography (NSL) process; the Mo poisoned the catalyst and prevented CNT growth where deposited, and as a result, a periodic CNT pattern was obtained. Using this method, the uniformity of the CNT array can be improved by preventing the negative effect of arrangement defects in self-assembled monolayers. The size and the period of the CNT array can be adjusted by careful selection of the polystyrene (PS) sphere diameter. X-ray photoelectron spectroscope (XPS) analysis revealed that the Co catalyst was ineffective on the areas of Mo deposition due to the diffusion of Co into the Mo layer.


Assuntos
Nanotecnologia/métodos , Nanotubos de Carbono/química , Catálise , Cobalto/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Molibdênio/química , Propriedades de Superfície , Titânio/química
4.
Nanoscale Res Lett ; 13(1): 351, 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30392105

RESUMO

A C60-PEI-rGO hybrid was prepared by incorporating the fullerene (C60) on the surface of PEI-modified reduced graphene oxide (rGO) and then used to modify the epoxy (EP) resin. Subsequently, the structure of GO and C60-PEI-rGO hybrid were well characterized, showing that the C60 was homogenously anchored on the surface of PEI-rGO. The flame retardancy, mechanical properties, and thermal stability of as-prepared C60-PEI-rGO/EP nanocomposites were systematically investigated. Results show that the C60-PEI-rGO hybrid exhibits high flame retarding efficiency for EP. Specifically, the time to ignition of epoxy increases from 68 to 89 s with the addition of 1.0 wt% C60-PEI-rGO, which are unusual in polymer nanocomposites. In the meantime, the peaks of the heat release rate and total heat release of the modified epoxy reduce by 40.0% and 15.6%, respectively. The synergistic flame retardant mechanism of C60-PEI-rGO to EP is attributed to its unique structure combining both the high efficiency in capturing free radicals by C60, the barrier effect of layered of rGO and increase of crosslinking density of epoxy. It is shown that the thermal stability and mechanical properties of epoxy are simultaneously improved with the addition of C60-PEI-rGO. This work may pioneer a new and efficient method to fabricate fire retardant thermosetting resins with simultaneously other improved properties.

5.
Materials (Basel) ; 10(6)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28772961

RESUMO

In this study, a 3-µm-thick AlGaN film with an Al mole fraction of 10% was grown on a nanoscale-patterned sapphire substrate (NPSS) using hydride vapor phase epitaxy (HVPE). The growth mechanism, crystallization, and surface morphology of the epilayers were examined using X-ray diffraction, transmission electron microscopy (TEM), and scanning electron microscopy at various times in the growth process. The screw threading dislocation (TD) density of AlGaN-on-NPSS can improve to 1-2 × 108 cm-2, which is significantly lower than that of the sample grown on a conventional planar sapphire substrate (7 × 108 cm-2). TEM analysis indicated that these TDs do not subsequently propagate to the surface of the overgrown AlGaN layer, but bend or change directions in the region above the voids within the side faces of the patterned substrates, possibly because of the internal stress-relaxed morphologies of the AlGaN film. Hence, the laterally overgrown AlGaN films were obtained by HVPE, which can serve as a template for the growth of ultraviolet III-nitride optoelectronic devices.

6.
Opt Express ; 13(6): 2058-63, 2005 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-19495090

RESUMO

The orientational photorefractive effect was observed in an organic-inorganic nanocomposite of nematic liquid crystal hybridized with montmorillonite clay. Both the self-diffraction and beam-coupling effects were evaluated in a two-wave-mixing experiment in conjunction with an externally applied dc field. The experimental results indicate that photoinduced generation was enhanced by the addition of smectite clay with adequate concentration. Physically, the drifting ion charges were trapped by clay layers and separated by interlayer cations, creating an internal, spatially modulated space-charge field, which led to nematic molecular orientation and, then, refractive-index modulation via the electro-optical response. The diffraction efficiency as well as the beam-coupling ratio of the phase gratings recorded in the cells of the nematic liquid crystal hybridized with montmorillonite clay was found to be two to three times higher than that in the pristine nematic cell.

7.
Chem Commun (Camb) ; (7): 886-7, 2003 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-12739661

RESUMO

The solvothermal reaction of elemental zinc with sulfur in ethylenediamine (en) as solvent yields [ZnS-0.5(NH2CH2CH2NH2)], 1, an unprecedented ethylenediamine pillared ZnS layered compound, containing two dimensional (2-D) boat-type 6-membered rings, which was characterized by ab initio structure solution from powder diffraction data (SDPD).

8.
ACS Nano ; 5(8): 6500-6, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21780845

RESUMO

This work demonstrates the processing and characterization of the transparent and highly electrically conductive film using few-walled carbon nanotubes (FWCNTs) decorated with Pd nanoparticles as fillers. The approach included functionalizing the FWCNTs, immersing them in an aqueous solution of palladate salts, and subsequently subjecting them to a reduction reaction in H(2). Field-emission scanning electron microscopy and transmission electron microscopy images showed that the functionalized FWCNTs (f-FWCNTs) were decorated with uniform and homogeneous Pd nanoparticles with an average diameter of 5 nm. A shift of the G-band to a higher frequency in the Raman spectra of the Pd-decorated f-FWCNTs (Pd@f-FWCNTs) illustrates that the p-type doping effect was enhanced. X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy showed that PdCl(2) was the primary decoration compound on the f-FWCNTs prior to the reduction reaction and that Pd nanoparticles were the only decorated nanoparticles after H(2) reduction. The contact resistance between the metallic materials and the semiconducting CNTs in FWCNTs, controlled by the Schottky barrier, was significantly decreased compared to the pristine FWCNTs. The decrease in contact resistance is attributed to the 0.26 eV increase of the work function of the Pd@f-FWCNTs. Extremely low sheet resistance of 274 ohm/sq of the poly(ethylene terephthalate) substrates coated with Pd@f-FWCNTs was attained, which was 1/25 the resistance exhibited by those coated with FWCNTs, whereas the same optical transmittance of 81.65% at a wavelength of 550 nm was maintained.

9.
ACS Nano ; 4(3): 1327-36, 2010 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-20184384

RESUMO

In this study, we prepared carbon nanotube (CNT) forests exhibiting two types of optical properties: so-called "darkest materials" and films displaying iridescence phenomena. The darkest materials, comprising vertically aligned CNT (VA-CNT) forests, displayed extremely low reflections as a result of the rough surface and the trapping of light in the CNT forests. The lengths of the CNTs in the CNT forests had a strong influence on whether the light transmitted through the CNT forest or reflected from the substrate. From an investigation of the limitations of the darkest materials of CNT forests, we prepared CNT surfaces running the gamut from dark materials to iridescent. To study iridescence phenomena, we prepared two kinds of patterns of CNT forests on flexible polycarbonate substrates: CNTs arrayed in hexagonal-hole patterns and broccoli-like CNTs, the latter formed through a combination of inverse nanosphere lithography (INSL) and a poisoned-catalyst mechanism. In the patterned CNT forests, even though the refractive index difference between the CNT film and air was extremely low and even though the CNTs could trap the incident light, the iridescence phenomenon remained, inducing colorful images from the CNT films.

10.
Bioresour Technol ; 101(13): 4889-94, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20022241

RESUMO

This work studied the concentration of hydrolyzates obtained from dilute acid hydrolysis of rice straw using nanofiltration (NF). In order to minimize the Donnan exclusion effect of the membrane, the hydrolyzate solution was controlled at low pH value. Negative retentions of both furans and carboxylic acids were observed. The maximum separation factor of acetic acid over xylose was 49, while the maximum separation factor of acetic acid over arabinose was 52, when the system was operated at pH 2.9 and an applied pressure of 24.5-34.3 bar. The separation factors of inhibitors over glucose became infinity due to the complete retention of glucose. The separation performance decreased when the operating temperature was increased from 25 to 40 degrees C. The flux deterioration was recovered by flushing with 0.01 N of NaOH and water.


Assuntos
Biotecnologia/métodos , Ácidos Carboxílicos/isolamento & purificação , Furanos/isolamento & purificação , Oryza/metabolismo , Arabinose/química , Carboidratos/química , Ácidos Carboxílicos/química , Filtração , Furanos/química , Glucose/química , Concentração de Íons de Hidrogênio , Hidrólise , Pressão , Hidróxido de Sódio/química , Temperatura , Água/química , Xilose/química
11.
Biomaterials ; 31(21): 5575-87, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20427083

RESUMO

The interaction of ultra-nanocrystalline diamond (UNCD) with neural stem cells (NSCs) has been studied in order to evaluate its potential as a biomaterial. Hydrogen-terminated UNCD (H-UNCD) films were compared with standard grade polystyrene in terms of their impact on the differentiation of NSCs. When NSCs were cultured on these substrates in medium supplemented with low concentration of serum and without any differentiating factors, H-UNCD films spontaneously induced neuronal differentiation on NSCs. By direct suppression of mitogen-activated protein kinase/extracellular signaling-regulated kinase1/2 (MAPK/Erk1/2) signaling pathway in NSCs using U0126, known to inhibit the activation of Erk1/2, we demonstrated that the enhancement of Erk1/2 pathway is one of the effects of H-UNCD-induced NSCs differentiation. Moreover, functional-blocking antibody directed against integrin beta1 subunit inhibited neuronal differentiation on H-UNCD films. This result demonstrated the involvement of integrin beta1 in H-UNCD-mediated neuronal differentiation. Mechanistic studies revealed the cell adhesion to H-UNCD films associated with focal adhesion kinase (Fak) and initiated MAPK/Erk1/2 signaling. Our study demonstrated that H-UNCD films-mediated NSCs differentiation involves fibronectin-integrin beta1 and Fak-MAPK/Erk signaling pathways in the absence of differentiation factors. These observations raise the potential for the use of UNCD as a biomaterial for central nervous system transplantation and tissue engineering.


Assuntos
Diferenciação Celular/fisiologia , Diamante/química , Nanopartículas/química , Neurônios/fisiologia , Células-Tronco/fisiologia , Animais , Biomarcadores/metabolismo , Butadienos/metabolismo , Adesão Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Inibidores Enzimáticos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibronectinas/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Integrina beta1/metabolismo , Teste de Materiais , Camundongos , Neurônios/citologia , Nitrilas/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco/citologia , Propriedades de Superfície
12.
Nanotechnology ; 19(46): 465303, 2008 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21836241

RESUMO

The unique heating property of microwave irradiation on carbon nanotubes (CNTs) was applied in fabrication of a new architecture of two-dimensional metallic nanobowl array on a thermoplastic substrate. Vertically aligned CNT film was grown on a metal coated polystyrene (PS) submicron sphere array and then transferred onto a polycarbonate (PC) substrate by microwave heating. The back diffracted light spectra of this structure were measured and discrepancies between the spectra and that predicted from a diffraction relationship were studied. It is suggested that the discrepancies were related to the shape and the refractive indices of the materials.

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