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1.
Braz J Biol ; 83: e270892, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466510

RESUMO

This study examines the in vitro growth and ex vitro establishment of Brassavola tuberculata in relation to the micropropagation system and sucrose concentration employed in the in vitro culture. A completely randomized experimental design was utilized, employing a 2 x 5 factorial arrangement. The experimental period began with seedlings cultivated in vitro for 180 days, which were subsequently transferred to Murashige and Skoog culture media containing sucrose concentrations of 0, 15, 30, 45, or 60 g L-1. The cultures were subjected to two micropropagation systems: conventional and gas exchange. After 90 days of in vitro cultivation, the plants were evaluated, transplanted into a substrate, and placed in a screened nursery for ex vitro cultivation. After 300 days of ex vitro cultivation, the survival and initial characteristics of the plants were assessed. The micropropagation system allowing gas exchange and sucrose concentrations up to 30 g L-1 enhanced the shoot and root growth of in vitro propagated plants. No noticeable anatomical differences were observed after 90 days of in vitro culture among the different sucrose concentrations and micropropagation systems used. In the ex vitro establishment, irrespective of sucrose concentration, the micropropagation system facilitating gas exchange positively influenced all evaluated characteristics.


Assuntos
Sacarose , Sacarose/farmacologia , Meios de Cultura
2.
J. nurs. health ; 9(1): 199102, jan. 8, 2019.
Artigo em Português | BDENF - Enfermagem, LILACS | ID: biblio-1029209

RESUMO

Objetivo: conhecer as percepções dos graduandos em Enfermagem sobre violência contra a mulher. Métodos: estudo qualitativo realizado com 16 graduandos em Enfermagem entre abril e junho de 2016. Dados coletados por entrevista e realizada a análise de conteúdo. Resultados: foram determinadas como categorias: entendimento sobre violência de gênero, abordagem da violência de gênero na formação dos graduandos, percepção sobre a atuação do enfermeiro na atenção às mulheres em situação de violência e considerações sobre o atendimento ideal à mulher em situação de violência. Considerações finais: a violência e a desigualdade de gênero são percebidas pelos acadêmicos. O papel do enfermeiro é destacado nas habilidades de comunicação e acolhimento. Os graduandos não se identificam como parte da equipe de saúde que receberá a mulher em situação de violência e percebem o tema no currículo da graduação. Estudos semelhantes contribuirão com a discussão sobre a violência contra a mulher.


Objective: to learn how nursing graduate students perceive violence against women. Methods: qualitative analysis carried out with 16 nursing students from April to June 2016. Data were collected in interviews and content was analyzed. Results: four categories were discerned: overall understanding about gender-related violence; approach towards gender-related violence during student’s graduation; perception about nurse’s role when assisting violated women; considerations about the best approach to take when assisting violated women. Final considerations: gender-related violence is noticed by students, as much as gender inequality. Nurse’s highlighted role is the ability to communicate and to foster patient care. Undergraduate students do not identify as active part of health care team. However, they identify the theme in the University’s undergraduation syllabus. Similar researches can contribute to discuss violence against women.


Assuntos
Humanos , Enfermagem , Estudantes de Enfermagem , Violência contra a Mulher
3.
Phys Rev Lett ; 110(10): 105502, 2013 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-23521270

RESUMO

Recently, Geblinger et al. [Nat. Nanotechnol. 3, 195 (2008)] reported the experimental realization of carbon nanotube S-like shaped nanostructures, the so-called carbon nanotube serpentines. We report here results from multimillion fully atomistic molecular dynamics simulations of their formation. We consider one-µm-long carbon nanotubes placed on stepped substrates with and without a catalyst nanoparticle on the top free end of the tube. A force is applied to the upper part of the tube during a short period of time and turned off; then the system is set free to evolve in time. Our results show that these conditions are sufficient to form robust serpentines and validates the general features of the "falling spaghetti model" proposed to explain their formation.

4.
Nano Lett ; 12(8): 4110-6, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22731916

RESUMO

In this work, an atomic force microscope (AFM) is combined with a confocal Raman spectroscopy setup to follow in situ the evolution of the G-band feature of isolated single-wall carbon nanotubes (SWNTs) under transverse deformation. The SWNTs are pressed by a gold AFM tip against the substrate where they are sitting. From eight deformed SWNTs, five exhibit an overall decrease in the Raman signal intensity, while three exhibit vibrational changes related to the circumferential symmetry breaking. Our results reveal chirality dependent effects, which are averaged out in SWNT bundle measurements, including a previously elusive mode symmetry breaking that is here explored using molecular dynamics calculations.

5.
Rev. bras. plantas med ; 14(4): 617-623, 2012. tab
Artigo em Português | LILACS | ID: lil-664012

RESUMO

O presente trabalho teve como objetivo estudar a influência dos reguladores vegetais BAP e GA3 como tratamentos pré-germinativos no processo de germinação e desenvolvimento inicial de plântulas de Dendrobium nobile, espécie importante pelas propriedades farmacológicas como anti-oxidante, vasodilatadora e até mesmo anti-cancerígena, além do valor ornamental. Os tratamentos pré-germinativos consistiram de BAP e GA3, separadamente, nas concentrações de 0,0; 1,0; 2,0 e 5,0 mg L-1. Após seis meses da semeadura in vitro e manutenção em câmara de germinação e de crescimento com temperatura e foto-período controlados (12 horas e 23ºC ± 2), foram avaliados os parâmetros número de sementes germinadas, porcentagem de germinação, massa fresca e altura das plântulas, diâmetro e número de pseudobulbos, número de folhas, número de raízes, e o comprimento da maior raiz. O delineamento experimental foi inteiramente casualizado. Todas as variáveis foram submetidas à análise de variância e de regressão, quando significativas. As sementes de D. nobile germinaram melhor na ausência de reguladores vegetais e os tratamentos com BAP ou GA3 na embebição das sementes pouco beneficiaram o desenvolvimento in vitro de D. nobile.


The present study aimed to investigate the influence of plant growth regulators BAP and GA3 as pre-germinative treatment in the process of germination and initial development of seedlings of Dendrobium nobile, a species important for its pharmacological properties like antioxidant, vasodilator and even anticancer, besides its ornamental value. Pre-germinative treatments consisted of BAP and GA3, separately, at the concentrations of 0.0; 1.0; 2.0 and 5.0 mg L-1. At six months after in vitro sowing and maintenance in a germination and growth chamber with controlled temperature and photoperiod (12 hours and 23ºC ± 2), the following parameters were evaluated: number of germinated seeds, percentage of germination, fresh mass and height of seedlings, number and diameter of pseudo-bulbs, number of leaves, number of roots, and length of the largest root. The experimental design was completely randomized. All variables underwent analysis of variance and regression analysis when significant. D. nobile seeds presented better germination in the absence of plant growth regulators and the treatments with BAP or GA3 in seed imbibition little benefited D. nobile in vitro development.


Assuntos
Germinação , Crescimento e Desenvolvimento , Reguladores de Crescimento de Plantas/análise , Sementes/crescimento & desenvolvimento , Dendrobium/crescimento & desenvolvimento , Plântula
6.
Nanotechnology ; 21(38): 385101, 2010 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-20798464

RESUMO

Development of RNA interference (RNAi) technology utilizing short interfering RNA sequences (siRNA) has focused on creating methods for delivering siRNAs to cells and for enhancing siRNA stability in vitro and in vivo. Here, we describe a novel approach for siRNA cellular delivery using siRNA coiling into carboxyl-functionalized single-wall carbon nanotubes (SWCNTs). The CNT-siRNA delivery system successfully demonstrates nonspecific toxicity and transfection efficiency greater than 95%. This approach offers the potential for siRNA delivery into different types of cells, including hard-to-transfect cells, such as neuronal cells and cardiomyocytes. We also tested the CNT-siRNA system in a non-metastatic human hepatocellular carcinoma cell line (SKHep1). In all types of cells used in this work the CNT-siRNA delivery system showed high efficiency and apparent no side effects for various in vitro applications.


Assuntos
Nanotubos de Carbono/química , RNA Interferente Pequeno/administração & dosagem , Transfecção , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Humanos , Masculino , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Nanotubos de Carbono/ultraestrutura , Neurônios/citologia , Neurônios/metabolismo , Interferência de RNA , Ratos , Ratos Wistar
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