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1.
J Public Health Res ; 12(3): 22799036231193071, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37622100

RESUMO

Background: The COVID-19 pandemic brought changes to primary school lunches leading to concerns over nutritional quality and uptake of lunches by vulnerable children. Regional data from Tayside, Scotland, showed that only 55% of children who were eligible for free school meals took these (normal uptake pre-pandemic was 66%). The current work aimed to identify teachers' perceptions of meal provisioning in primary schools during the first year of the COVID-19 pandemic. Design and methods: A cross-sectional online survey was carried out among primary school teachers across Tayside, Scotland. Using an online survey (21 questions combining multiple choice formats and open text) and interviews, primary school teachers shared their views on food quality, quantity, meal choices and factors influencing uptake of primary school lunches. Interviews were recorded, transcribed and thematically analysed with respect to factors influencing consumption. Results: The survey was completed by 41 teachers and 8 participated in a follow up interview. Around one-third (29%) of primary school teachers believed the quality of lunches had decreased and cited poor appearance of food, use of takeaway containers and food wastage. The lunch format was viewed negatively principally relating to the substitution of hot lunches with cold sandwiches, portion sizes, choice and perceived value for money. Concerns were expressed about acceptability and how far the meals contributed to food security. Conclusions: Further work on food provisioning is needed in order to identify ways to provide a nutritional safety net for vulnerable children.

2.
Appl Opt ; 34(24): 5263-7, 1995 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-21060343

RESUMO

The Multiplex Fabry-Perot Interferometer (MFPI) is a unique instrument, incorporating the wide spectral-bandwidth capability of the Michelson interferometer with the small size and high resolution of the Fabry-Perot interferometer. The MFPI is, structurally, a standard Fabry-Perot in which the scanning distance is allowed to be very large, of the order of centimeters. The signal recorded through this distance is Fourier transformed as would be the interferogram produced by a Michelson interferometer. The result is a spectrum containing very high-resolution information over a moderately large optical bandwidth. The MFPI is much smaller than a Michelson producing the same resolution and covers a much broader bandwidth than a Fabry-Perot used in the usual fashion. We present a basic description of the operating theory for the MFPI in terms familiar to the Michelson spectroscopist.

3.
Appl Opt ; 34(24): 5268-77, 1995 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-21060344

RESUMO

The Multiplex Fabry-Perot interferometer (MFPI) consists of a Fabry-Perot interferometer in which the étalon plate separation is changed over a large optical distance. Fourier transformation of the resultant interferogram allows one to treat the multiple reflections within the étalon cavity in a manner analogous to an array of Michelson-type interferometers. However, the scan distance required by the MFPI is much less than for a comparable Michelson. The design and construction of the MFPI are described. Solar absorption spectra measured with this instrument are compared with results from the FASCODE atmospheric model.

4.
Nucleic Acids Res ; 20(2): 359-64, 1992 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-1346929

RESUMO

A cDNA encoding a nuclear-encoded chloroplast nucleic acid-binding protein (NBP) has been isolated from maize. Identified as an in vitro DNA-binding activity, NBP belongs to a family of nuclear-encoded chloroplast proteins which share a common domain structure and are thought to be involved in posttranscriptional regulation of chloroplast gene expression. NBP contains an N-terminal chloroplast transit peptide, a highly acidic domain and a pair of ribonucleoprotein consensus sequence domains. NBP is expressed in a light-dependent, organ-specific manner which is consistent with its involvement in chloroplast biogenesis. The relationship of NBP to the other members of this protein family and their possible regulatory functions are discussed.


Assuntos
Cloroplastos/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/genética , Proteínas de Plantas/genética , Zea mays/genética , Sequência de Aminoácidos , Northern Blotting , Southern Blotting , Proteínas de Ligação a DNA/química , Dados de Sequência Molecular , Proteínas de Plantas/química , Polimorfismo de Fragmento de Restrição
5.
Photosynth Res ; 31(2): 99-111, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24407982

RESUMO

We have isolated and characterized two nuclear mutations which affect plastoquinone accumulation in maize. The mutations, hcf103 and hcf114, modify the same genetic locus. Plants homozygous for either mutant allele exhibit reduced PS II electron transport activity, reduced variable chlorophyll fluorescence and reduced delayed fluorescence yield. In these ways, hcf103 and hcf114 resemble previously described PS II mutants which lack stably assembled PS II reaction center complexes. However, unlike most previously described PS II mutants, hcf103 and hcf114 possess stable membrane-associated PS II complexes. Plastoquinone (PQ-9), which performs a variety of redox functions essential to normal non-cyclic electron transport, is severely depleted in the mutants. The lack of PS II electron transport activity is attributed to the absence of PQ-9. This is the first report of mutants deficient in PQ which do not also suffer serious pleiotropic defects.

6.
Photosynth Res ; 24(1): 81-8, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24419768

RESUMO

Photosynthesis mutations were induced in maize lines bearing the transposable DNA element system, Mutator. Two Photosystem I mutants (hcf101 and hcf104) which were isolated are described here. Maize plants homozygous for the hcf104 mutation are seedling lethal and exhibit a high in vivo chlorophyll fluorescence yield. They lack ∼60% of CP1, P700 and PSI-specific electron transport activity relative to normal sibling plants. The comparable depletion of these three measures of PS I content conforms to the pattern reported for many other PS I-deficient mutants. Maize plants homozygous for hcf101 are seedling lethal and also exhibit high in vivo chlorophyll fluorescence yield. They lack 80-90% of CP1 and P700 but sustain steady state levels of PS I-specific electron transport activity at 70% of normal. Previous reports of similar apparent PS I hyperactivity are discussed and an explanation for the elevated steady state level of PS I electron transport activity in hcf101 is proposed.

7.
Photosynth Res ; 18(1-2): 33-59, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24425160

RESUMO

The discovery of a new maize (Zea mays L.) transposon system, Mutator, and the cloning of the 1.4 kilobase transposon, Mul, have made feasible the isolation of nuclear photosynthetic genes which are recognized only by their mutant phenotype. Mutant maize plants which express a high chlorophyll fluorescent (hcf) phenotype due to a defect in the electron transport or photophosphorylation apparatus have been isolated following mutagenesis with an active Mutator stock. The affected genes and their products in these mutants are inaccessible to classical methods of analysis. However, mutagenesis with the Mutator transposon makes it possible to isolate these genes.Although the PSII-deficient mutant hcf3 has been thoroughly studied by classical photo-biological methods, the nature of the lesion which results in the observed phenotype has not been established. A Mutator-induced allele of hcf3 has been isolated. A fragment of genomic DNA has been identified which is homologous to Mul and co-segregates with the mutant phenotype. This fragment is expected to contain a portion of the hcf3 locus which will be used to clone the normal gene. Direct study of the gene can provide insight into the nature and function of its polypeptide product.This approach can be used to study any photosynthetic gene which has been interrupted by a transposon. The isolation of more than 100 different chemically-induced hcf mutants, most of which can not be fully characterized using classical means, indicates the wealth of information which can be obtained using a transposon tagging technique.

8.
11.
J Ky Med Assoc ; 72(10): 565, 1974 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4443635
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