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1.
J Vis Exp ; (137)2018 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-30102281

RESUMO

The ubiquitous presence of plastic debris in the ocean is widely recognized by the public, scientific communities, and government agencies. However, only recently have microplastics in freshwater systems, such as rivers and lakes, been quantified. Microplastic sampling at the surface usually consists of deploying drift nets behind either a stationary or moving boat, which limits the sampling to environments with low levels of suspended sediments and floating or submerged debris. Previous studies that employed drift nets to collect microplastic debris typically used nets with ≥300 µm mesh size, allowing plastic debris (particles and fibers) below this size to pass through the net and elude quantification. The protocol detailed here enables: 1) sample collection in environments with high suspended loads and floating or submerged debris and 2) the capture and quantification of microplastic particles and fibers <300 µm. Water samples were collected using a peristaltic pump in low-density polyethylene (PE) containers to be stored before filtering and analysis in the lab. Filtration was done with a custom-made microplastic filtration device containing detachable union joints that housed nylon mesh sieves and mixed cellulose ester membrane filters. Mesh sieves and membrane filters were examined with a stereomicroscope to quantify and separate microplastic particulates and fibers. These materials were then examined using a micro-attenuated total reflectance Fourier transform infrared spectrometer (micro ATR-FTIR) to determine microplastic polymer type. Recovery was measured by spiking samples using blue PE particulates and green nylon fibers; percent recovery was determined to be 100% for particulates and 92% for fibers. This protocol will guide similar studies on microplastics in high velocity rivers with high concentrations of sediment. With simple modifications to the peristaltic pump and filtration device, users can collect and analyze various sample volumes and particulate sizes.


Assuntos
Monitoramento Ambiental/métodos , Plásticos/química , Poluentes Químicos da Água/análise
2.
J Adv Nurs ; 74(2): 350-363, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28792608

RESUMO

AIM: The aim of this study was to describe co-parenting communication in couples in the context of caregiving for children prenatally diagnosed and born with complex health conditions. BACKGROUND: Foetal diagnosis of complex health conditions such as heart, central nervous system, or abdominal anomalies are confirmed more often than ever before. Following diagnosis, parents face challenges beginning before birth. The quality of co-parenting, when two individuals relate to each other as parents and share parental responsibilities, can have an impact on child health and development. Yet, little is known about co-parenting during the transition to parenthood after foetal diagnosis. DESIGN: This secondary analysis of interview data was informed by Bowlby's theoretical work on a parent's view of self as caregiver and the literature on co-parenting. METHODS: Data were drawn from a larger, mixed methods, longitudinal study and included audio-recorded interviews conducted with 16 parents participating as eight couples after foetal diagnosis during the third trimester of pregnancy in 2011-2012 and again when children were 14-37 months old in 2014. Analysis of interviews transcribed verbatim focused on co-parenting communication. FINDINGS: Co-parenting communication regarding support, agreement and information sharing and a new category of shared meaning were related to the diagnosis before birth. Later, couples evolved in their co-parenting communication while caring for their toddlers and working towards achieving a sense of normalcy. CONCLUSION: Variation in co-parenting communication among couples preparing and caring for children with complex health conditions, including the development of a shared meaning of the child's diagnosis, needs further investigation to inform nursing assessment and guide tailored interventions.


Assuntos
Adaptação Psicológica , Cuidadores/psicologia , Anormalidades Congênitas/enfermagem , Crianças com Deficiência/psicologia , Poder Familiar/psicologia , Pais/psicologia , Estresse Psicológico , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Relações Pais-Filho , Gravidez , Adulto Jovem
3.
Magn Reson Chem ; 54(2): 126-31, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26332615

RESUMO

We report through-space (TS) (19)F-(19)F coupling for ortho-fluoro-substituted Z-azobenzenes. The magnitude of the TS-coupling constant ((TS) JFF ) ranged from 2.2-5.9 Hz. Using empirical formulas reported in the literature, these coupling constants correspond to non-bonded F-F distances (dFF) of 3.0-3.5 Å. These non-bonded distances are significantly smaller than those determined by X-ray crystallography or density functional theory, which argues that simple models of (19)F-(19)F TS spin-spin coupling solely based dFF are not applicable. (1)H, (13)C and (19)F data are reported for both the E and Z isomers of ten fluorinated azobenzenes. Density functional theory [B3YLP/6-311++G(d,p)] was used to calculate (19) F chemical shifts, and the calculated values deviated 0.3-10.0 ppm compared with experimental values.

4.
Pharmacol Biochem Behav ; 90(2): 218-25, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18031799

RESUMO

Dysregulation of mesolimbic dopamine (DA) neurotransmission has been implicated in bipolar disorder. DA release in the nucleus accumbens is reduced in rats treated chronically with the mood stabiliser lithium, and this effect is maintained for 3 days after withdrawal from the lithium treatment. We tested whether this decrease in DA release is due to an increase in D(2/3) autoreceptor sensitivity. In vivo microdialysis studies showed that in the shell of the nucleus accumbens, dialysate DA was decreased following chronic lithium treatment and 3 days after withdrawal from lithium treatment. The elevation of dialysate DA induced by local blockade of the terminal D(2/3) receptor was reduced in both lithium treated and lithium withdrawn groups. In vitro electrophysiology studies showed that chronic lithium treatment (and lithium withdrawal) did not alter either basal firing rate of DA neurones in the ventral tegmental area, or somatodendritic D(2/3) autoreceptor-mediated inhibition of firing. D(2) mRNA expression in the ventral tegmental area was unchanged by lithium treatment and lithium withdrawal. Our data suggest that the decrease in dopamine release in the nucleus accumbens induced by chronic lithium treatment is not the result of increased terminal or somatodendritic autoreceptor sensitivity or decreased firing rate of DA neurones.


Assuntos
Autorreceptores/efeitos dos fármacos , Dopamina/fisiologia , Cloreto de Lítio/farmacologia , Receptores de Dopamina D2/efeitos dos fármacos , Receptores de Dopamina D3/efeitos dos fármacos , Animais , Autorreceptores/fisiologia , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , RNA Mensageiro/análise , Ratos , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/fisiologia , Receptores de Dopamina D3/fisiologia , Sulpirida/farmacologia , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo
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