Abstract Starch aerogels are a clean‐label alternative to produced active packaging aimed at preserving food products. This study aims to produce water‐absorbent and reusable aerogels from different ...starches and investigates their properties according to the type of starch. The aerogels are produced using different starch concentrations and evaluated in terms of morphology, density, porosity, relative crystallinity, texture properties, water absorbent capacity, reusability as water absorbent, and water absorption rate. The aerogel is applied as an absorbent of chicken breast exudate. The starches’ amylose content is 28.2%, 27.4%, 45.4%, and 30.2% for the potato, cassava, bean, and maize starches, respectively. All aerogels display physical integrity and porous structures with low density and high porosity, and their relative crystallinity decreases compared to the starches. The texture properties show great elasticity. The aerogels present high water absorption capacity, ranging from 685% to 1714%. Potato and bean starch aerogels can be reused as water absorbents 12 times showing, after the first immersion, a stable water retention rate over the reusable period. The maize starch‐based aerogel is applied as an absorbent for chicken breast exudate, reaching 39% absorption, proving to be an excellent material for application as active food packaging for fresh food preservation.
A publicação da Lei n.º 12.305 de 02 de agosto de 2010 – Política Nacional de Resíduos Sólidos (PNRS) introduz princípios já conhecidos na área ambiental, mas pouco utilizados pelo público. Um destes ...princípios é a logística reversa. Este trabalho realizou um levantamento com as cinco empresas de maior representatividade no setor de comércio de materiais elétricos no município de Cuiabá/MT. O principal objetivo foi conhecer a realidade do gerenciamento de resíduos devolvidos de lâmpadas que contenham mercúrio. Utilizou-se de entrevistas com gerentes das empresas escolhidas, onde foram avaliadas informações a respeito de conhecimento da legislação, aplicação desta, gerenciamento dos resíduos, dentre outras. Os resultados demonstraram que no município de Cuiabá, não há alternativa adequada para a devolução de lâmpadas de mercúrio.
The relative quantification of gene expression is mainly realized through reverse transcription-quantitative PCR (RT-qPCR). However, the accuracy of this technique is deeply influenced by the ...expression stability of the reference genes used for data normalization. Therefore, the selection of suitable reference genes for a given experimental condition is a prerequisite in gene expression studies.
Dichelops melacanthus
(Hemiptera: Pentatomidae) is an important phloem sap-sucking insect pest of soybean, wheat, and maize in Brazil. Most of the genetic and molecular biology studies require gene expression analysis. Nevertheless, there are no reports about reference genes for RT-qPCR data normalization in
D. melacanthus
. In this study, we evaluated the expression stability of nine candidate reference genes (
nadh
,
sdhb
,
gapdh
,
fau
,
ef1a
,
rpl9
,
ube4a
,
gus
and
rps23
) in different developmental stages, body parts, sex, starvation-induced stress and dsRNA exposure by RefFinder software that integrates the statistical algorithms geNorm, NormFinder, BestKeeper, and ΔCt method. Our results showed that
ef1a
and
nadh
are the most stable reference genes for developmental stages,
fau
and
rps23
for sex,
ube4a
and
rps23
for body parts,
rpl9
and
fau
for starvation stress, and
nadh
and
sdhb
for dsRNA exposure treatment. The reference genes selected in this work will be useful for further RT-qPCR analyses on
D. melacanthus
, facilitating future gene expression studies that can provide a better understanding of the developmental, physiological, and molecular processes of this important insect pest. Moreover, the knowledge gained from these studies can be helpful to design effective and sustainable pest management strategies.
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