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1.
Child Adolesc Psychiatry Ment Health ; 16(1): 66, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35962396

RESUMO

BACKGROUND: The International Trauma Questionnaire-Child and Adolescent version (ITQ-CA) is a self-report measure that assesses posttraumatic stress disorder (PTSD) and complex PTSD (CPTSD) based on the diagnostic formulation of the 11th version of the International Classification of Diseases (ICD-11). This study aimed to provide a Chinese translation and psychometric evaluation of the ITQ-CA using a sample of mental-health service seeking adolescents in Mainland China. METHODS: The ITQ-CA was translated and back-translated from English to simplified Chinese and finalized with consensus from an expert panel. Adolescents ages 12-17 were recruited via convenience sampling from an outpatient psychiatric clinic in Mainland China. Participants completed the ITQ-CA; measures of four criterion variables (depression, anxiety, stress, adverse childhood experiences); and the PTSD Checklist for DSM-5 (PCL-5). Construct validity, concurrent validity, and comparison of PTSD caseness between ICD-11 and DSM-5 measures were assessed. RESULTS: The final sample consisted of 111 Chinese adolescents (78% female; mean age of 15.23), all diagnosed with a major depressive disorder. Confirmatory factor analysis indicated the two-factor second-order model provided optimal fit. All criterion variables were positively and significant correlated with the six ITQ-CA symptom cluster summed scores. In the present sample, 69 participants (62.16%) met symptom criteria for ICD-PTSD or CPTSD using the ITQ-CA, and 73 participants (65.77%) met caseness for DSM-5 PTSD using the PCL-5. Rates of PTSD symptom cluster endorsement and caseness deriving from both diagnostic systems were comparable. CONCLUSIONS: The Chinese ITQ-CA has acceptable psychometric properties and confers additional benefits in identifying complex presentations of trauma-related responses in younger people seeking mental health services.

2.
Psychiatry Res ; 315: 114700, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35803168

RESUMO

This study compares the psychological profile of Internally Displaced Persons (IDPs) and individuals living in host communities in the war-affected setting. We conducted a cross-sectional survey from October-November 2019. Subjects were recruited from six IDPs camps and the surrounding host communities within the metropolis of Maiduguri, Nigeria by convenience sampling. Data were collected using the Hausa version of Depression Anxiety Stress Scale-21, and analysed by logistic regression using adjusted odds ratio (AOR) at 95% Confidence Interval (CI). A total of 562 subjects were recruited. Living in IDP camp was the most significantly predictor of depression, anxiety, and stress. The common predictors were living in an IDP camp, and marital status (separated). Aged 18-29years was a protective factor compared to those ≥50years. Living in IDP camps, separated from partners, lack of education and pre-conflict employment were significant predictors of depression, anxiety and stress.


Assuntos
Ansiedade , Depressão , Refugiados , Humanos , Ansiedade/epidemiologia , Conflitos Armados , Estudos Transversais , Depressão/epidemiologia , Nigéria , Refugiados/psicologia
3.
Nanotechnology ; 22(23): 235701, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21474867

RESUMO

A facile large-scale synthesis approach for producing intrinsically p-type nanowires with uniform coverage of nanocrystals to form a highly interconnected porous nanowire network is of great demand for p-type sensing. Here, we have demonstrated synthesis of a very high aspect ratio (10(2)-10(5)) open network of interconnected hybrid nanocrystals-nanowire copper and copper oxide nanomaterials. The copper nanowire scaffold is employed to realize a porous and highly interconnected network of hybrid metal-metal oxide nanocrystal-nanowire structures. The structural and composition tunability of the hybrid nanomaterials is demonstrated. The hybrid copper-copper oxide nanowires exhibit enhanced gas/light sensing properties without any operating temperature. This may be attributed to enhanced medium diffusion due to the porous network of highly interconnected nanocrystal-nanowire structures.

4.
J Interpers Violence ; 36(19-20): NP10345-NP10370, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-31524036

RESUMO

Resilience is a key health protective factor for those with adverse childhood experiences (ACEs), but little research has explored how it manifests in early adulthood or across cultures. The purpose of this study was to generate a fuller understanding of resilience and its contribution to the relationships between mental health problems and ACEs among Chinese young adults in Hong Kong. Using a sequential explanatory mixed-methods design, 433 Chinese young adults aged 18 to 24 years were surveyed online to examine the relationships between ACEs, resilience, and mental health problems (depression, anxiety, maladjustment, and posttraumatic stress symptoms). Among them, 34 participants with ACEs were purposively selected and interviewed to explore cultural factors that influenced their resilience. Quantitative data were analyzed using multiple hierarchical regression analyses; qualitative data were analyzed using a qualitative descriptive approach. Higher cumulative ACE exposure was associated with higher severity of adjustment disorder and odds for screening positive for posttraumatic stress disorders, but not for symptoms of depression or anxiety. Resilience significantly contributed to explaining variances across all mental health outcomes over and beyond ACEs and in a protective fashion. Four themes emerged from qualitative interviews: (a) Privacy, emotional restraint, and "saving face"; (b) Conforming to preserve harmony; (c) A will to excel; and (d) Viewing adversity as a matter of luck. These findings suggest Chinese young adults' resilience was influenced by cultural norms of restraint, conformity, competition, and superstition. The present study provides a model for future studies using a mixed-methods design to deeply examine resilience among younger people exposed to early adversities within sociocultural, historical, or geographical contexts.


Assuntos
Experiências Adversas da Infância , Transtornos de Estresse Pós-Traumáticos , Adulto , Ansiedade/epidemiologia , China , Humanos , Saúde Mental , Adulto Jovem
5.
Nanotechnology ; 21(31): 315602, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20634568

RESUMO

A maskless method of employing polymer growth inhibitor layers is used to modulate the conflicting parameters of density and alignment of multi-junction nanowires via large-scale low temperature chemical route. This low temperature chemical route is shown to synthesize multi-junction nanostructures without compromising the crystal quality at the interfaces. The final morphology of optimized multi-junctions nanowire arrays can be demonstrated on various substrates due to substrate independence and low temperature processing. Here, we also fabricated devices based on density modulated multi-junction nanowires tuned to infiltrate nanoparticles. The fabrication of hierarchically structured nanowire/nanoparticles composites presents an advantageous structure, one that allows nanoparticles to provide large surface areas for dye adsorption, whilst the nanowires can enhance the light harvesting, electron transport rate, and also the mechanical properties of the films. This work can be of great scientific and commercial interest since the technique employed is of low temperature (<90 degrees C) and economical for large-scale solution processing, much valued in today's flexible display and photovoltaic industries.

6.
Sci Adv ; 6(42)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33067237

RESUMO

The atmosphere contains an abundance of fresh water, but this resource has yet to be harvested efficiently. To date, passive atmospheric water sorbents have required a desorption step that relies on steady solar irradiation. Since the availability and intensity of solar radiation vary, these limit on-demand desorption and hence the amount of harvestable water. Here, we report a polymer-metal-organic framework that provides simultaneous and uninterrupted sorption and release of atmospheric water. The adaptable nature of the hydro-active polymer, and its hybridization with a metal-organic framework, enables enhanced sorption kinetics, water uptake, and spontaneous water oozing. We demonstrate continuous water delivery for 1440 hours, producing 6 g of fresh water per gram of sorbent at 90% relative humidity (RH) per day without active condensation. This leads to a total liquid delivery efficiency of 95% and an autonomous liquid delivery efficiency of 71%, the record among reported atmospheric water harvesters.

7.
Compr Child Adolesc Nurs ; 43(1): 48-64, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30640560

RESUMO

In the absence of a mandatory reporting (MR) structure, it is unclear how nurses perceive or exercise their role in child protection. This study examined knowledge and perceptions of child protection and MR among nurses working in Hong Kong. This cross-sectional web-based survey used the Child Abuse Report Intention Scale to measure nurses' child protection knowledge and attitudes, and their perceived norms, control, and intention to report suspected maltreatment. Nurses also indicated if they support MR and to provide an explanation for their preference. Quantitative data were described and analyzed using bivariate and regression analyses. Open-ended responses were analyzed using directed content analysis. A convenient sample of 91 nurses working in Hong Kong completed the survey. The majority (86%) were female with a mean of 9.5 years of nursing experience; their mean knowledge score was 6.64 out of 13 (range 2-10). Compared with other maltreatment types, sexual abuse was perceived to be most severe and most likely to be reported. Perceived severity and attitudes toward child maltreatment was significantly associated with nurses' intention to report. Over half (58%) supported MR; those against MR expressed concerns about lack of support from management. Although nurses working in Hong Kong still hold polarized views about MR, findings point to the importance of creating a supportive reporting culture, and designing training programs that focus on changing perceptions about child protection in order to improve their tendency to report.


Assuntos
Conhecimento , Notificação de Abuso/ética , Enfermeiras e Enfermeiros/psicologia , Percepção , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Hong Kong , Humanos , Masculino , Enfermeiras e Enfermeiros/estatística & dados numéricos , Inquéritos e Questionários
8.
Nanotechnology ; 20(4): 045604, 2009 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-19417324

RESUMO

Several important synthetic parameters such as precursor concentration, rate of evaporation and reaction time are found to determine the growth of ZnO nanostructures. These reaction parameters can be tailored and tuned to produce a variety of nanostructures ranging from nanoparticles, nanorods and nanospheres. The nanorods are structurally uniform made up of crystallographically oriented attached nanoparticles while the nanospheres are made up of several closely packed and randomly aligned nanocrystallites. XRD spectra of both the nanoparticles and nanorods exhibit typical diffraction peaks of a well-crystalline wurtzite ZnO structure. Finally, solar cells made up of ZnO nanoparticles and nanorods electrodes with absorbed ruthenium dye (N3) were measured to have a power conversion efficiency of 0.87% and 1.32%, respectively.

9.
Biomater Sci ; 2(12): 1740-1749, 2014 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-32481952

RESUMO

Previous studies have shown that fundamental cell functions such as adhesion, proliferation, and morphology are regulated by the interaction of cells with basement membrane nano- and micron- scale surface topography. By taking the basement membrane as a guiding principle, the surface can be designed with biophysical cues in the form of surface topographies to modulate the cellular functions of vascular endothelial and smooth muscle cells, which are crucial for vascular diseases. Titanium-based materials whose surfaces are covered by a thin layer of titanium dioxide (TiO2) are utilized in several regenerative medicine applications such as vascular prosthetics. The utilization of TiO2-covered materials makes it essential to understand the interaction of cells with the TiO2 layer to control the cell response. While it has been shown by means of patterned micro- and nano-topography that it is important to regulate cell functions on non-metallic materials, it would be of interest in the field of regenerative medicine to study the cell response on patterned TiO2 surface layers. Previous studies have mostly focused on studying the cell response on random micro- and nano-roughened metallic and metal oxide surfaces as it is challenging to fabricate patterned TiO2 surface layers. Here, the biocompatibility of a method that is capable of the rational patterning of a continuous TiO2 surface layer of sub-100 nm resolution scale using thermally curable resin-based nanoimprinting was studied. The responses of human umbilical vein endothelial cell (HUVEC), such as proliferation, morphology and focal adhesions, and smooth muscle cell (SMC) proliferation and morphology to the nano-patterned TiO2 layer were investigated. Overall, the TiO2 layer with surface nano-gratings showed enhanced proliferation of HUVECs, while it significantly lowered the proliferation of SMCs as compared to the unpatterned control. The HUVECs and SMCs were shown by topography to be sensitive to the 70 nm gratings as evident by the regulation of proliferation and cell shape. A significantly lower focal adhesion density was found of HUVECs on TiO2 nano-gratings, while a significantly higher average focal adhesion size of HUVECs was seen on TiO2 nano-wells and nano-gratings, compared to the unpatterned controls.

10.
Nanoscale ; 5(22): 11283-90, 2013 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-24091468

RESUMO

This work focused on the development of a hybrid organic-inorganic TiO2 nanocomposite, which demonstrates the first ever report on harmful volatile organic compound (VOC) sensing and photocatalytic degradation-H2 production. The sensing and photocatalytic properties are enhanced by the synergetic effects of well-structured TiO2 nanotubes, metal nanoparticles and reduced graphene oxide loading for enhanced light absorption and charge-transfer kinetics. Hybridization of a functionalized TiO2 nanocomposite with a polyvinylidene fluoride (PVDF) matrix induced strong cross-linking networks between the inorganic-organic components, which promote mechanical reinforcement-flexibility and highly porous asymmetric structures. The developed solution processable nanocomposite has immense potential to remedy the global environmental and energy issues by producing clean water/air and energy from organic compound waste.


Assuntos
Grafite/química , Hidrogênio/química , Nanocompostos/química , Polivinil/química , Espectrofotometria , Compostos Orgânicos Voláteis/análise , Catálise , Gases/química , Cinética , Luz , Nanocompostos/ultraestrutura , Óxidos/química , Fotólise , Prata/química , Titânio/química , Compostos Orgânicos Voláteis/química
11.
Nanoscale ; 4(1): 194-205, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22075796

RESUMO

A lot of research on nanomaterials has been carried out in recent years. However, there is still a lack of nanostructures that have a combination of superior properties; both efficient electron transport and high surface area. Here, the authors have tried to develop hybrid α-Fe(2)O(3) flower-like morphology which exhibits both superior electron transport and high surface area. Intrigued by the unique properties of Fe(2)O(3) at the nanoscale and its abundance in nature, we have demonstrated a facile template-free solution based synthesis of hybrid α-Fe(2)O(3) comprising nanopetals nucleating radially from a 3D core. Due to its simplicity, the synthesis process can be easily reproduced and scaled up. We carried out in-depth studies on gas sensing and dye-sensitized solar cell (DSSC) device characterization so as to gain an understanding of how surface area and transport properties are affected by variation in morphology. The hybrid α-Fe(2)O(3) nanostructures are studied as potential candidates for gas sensors and for the first time as a working electrode for DSSC.

12.
ACS Appl Mater Interfaces ; 3(7): 2383-91, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21648469

RESUMO

In this work, enhancement of ionic conductivity and long-term stability through the addition of diphenylamine (DPA) in poly(ethylene oxide) (PEO) is demonstrated. Potassium iodide (KI) is adopted as the crystal growth inhibitor, and DPA is used as a charge transport enhancer in the electrolyte. The modified electrolyte is used with titanium dioxide (TiO2) nanoparticles, which is systematically tuned to obtain high surface area. The dye-sensitized solar cell (DSSC) showed a photocurrent of 14 mAcm2 with a total conversion efficiency of 5.8% under one sun irradiation. DPA enhances the interaction of the TiO2 nanoparticle film and the I-/I3- electrolyte leading to high ionic conductivity (3.5 × 10-3 Scm-1), without compromising on the electrochemical and mechanical stability. Electrochemical impedance spectroscopy (EIS) studies show that electron transport and electron lifetime are enhanced in the DPA added electrolyte due to reduced sublimation of iodine. The most promising feature of the electrolyte is increased device stability with 89% of the overall efficiency preserved even after 40 days.

13.
ACS Appl Mater Interfaces ; 2(7): 1844-50, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20617836

RESUMO

Mesophase ordering and structuring are carried out to attain optimized pore morphology, high crystallinity, stable porous framework, and crack-free mesoporous titanium dioxide (TiO(2)) films. The pore structure (quasi-hexagonal and lamellar) can be controlled via the concentration of copolymer, resulting in two different types of micellar packing. The calcination temperature is also controlled to ensure a well-crystalline and stable porous framework. Finally, the synthesized mesoporous TiO(2) film is modified by adding P25 nanoparticles, which act as scattering centers and function as active binders to prevent formation of microcracks. Adding P25 nanoparticles into mesoporous structure helps to provide strong light-harvesting capability and large surface area for high -efficiency dye-sensitized solar cells (DSSC). The short-circuit photocurrent density (J(sc)) of the cell made from mixture of mesoporous TiO(2) and P25 nanoparticles displays a higher efficiency of approximately 6.5% compared to the other homogeneous films. A combination of factors such as increased surface area, introduction of light-scattering particles, and high crystallinity of the mesoporous films leads to enhanced cell performance.


Assuntos
Membranas Artificiais , Nanopartículas , Energia Solar , Titânio , Porosidade
14.
Nanotechnology ; 19(25): 255706, 2008 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-21828666

RESUMO

A high-yield synthesis of SnO(2) nanoparticles via a facile, economical and easily scalable solid-state molten salt synthesis method has been demonstrated. The inorganic additive, molar ratios of chemicals and annealing temperature were found to control the size and porosity of the SnO(2) nanoparticles. The synthesized SnO(2) nanostructures were uniform, well dispersed and exhibited high crystallinity. Hydrogen sensors made from the SnO(2) nanoparticles were found to possess high sensitivity and stability. Other than tailoring the material's structure in terms of size and porosity, another potential method of enhancing the gas sensitivity is functionalization with noble Pd metal.

15.
Microbiology (Reading) ; 144 ( Pt 11): 2987-3002, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9846734

RESUMO

Vibrio anguillarum and Vibrio damselae are Gram-negative bacteria that cause systemic infections called vibriosis in fish. They can enter fish cells and survive as intracellular parasites. The host-pathogen interactions between these Vibrio species and the fish epithelial cell lines epithelioma papillosum of carp (EPC) and grunt-fin tissue (GF) cells, were examined using phase-contrast, scanning electron and confocal microscopy. In addition, potential signal transduction pathways that precede bacterial internalization were studied by using signal transduction inhibitors. Some Vibrio species induced morphological changes in fish cells and this allowed classification into a cytopathic group and a noncytopathic group. The cytopathic group could be subdivided into two invasive groups (I and II) and a cytotoxic group. Of the invasive strains V. anguillarum 811218-5W (group I) and G/Virus/5(3) (group II), genistein, a tyrosine kinase inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3) into EPC cells, whereas staurosporine, a protein kinase C inhibitor, accelerated internalization of both strains. Cytochalasin D, an inhibitor of microfilament polymerization, prevented internalization of both strains, whilst vincristin, a microtubule inhibitor, only inhibited internalization of V. anguillarum G/Virus/5(3). For the cytotoxic strain V. damselae ATCC 33539, extracellular products (ECP) alone caused morphological changes in EPC and GF. Bacterial internalization may not be important in the pathogenesis of this group. The non-cytopathic strain V. anguillarum S2/5/93(2) did not enter cells or induce any changes in EPC and GF monolayers. This study has identified some major differences between Vibrio species in their interactions with fish cells in vitro and will thus facilitate future studies of the molecular basis of pathogenesis of vibriosis.


Assuntos
Células Epiteliais/microbiologia , Doenças dos Peixes/microbiologia , Vibrioses/veterinária , Vibrio/patogenicidade , Animais , Aderência Bacteriana , Carpas , Células Cultivadas , Células Epiteliais/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Transdução de Sinais , Vibrio/fisiologia , Vibrio/ultraestrutura , Vibrioses/microbiologia , Virulência
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