153 research outputs found
Optimizacion del diseino de una red de distribucion de agua potable
En el presente reporte se present an los resultados obtenidos por el grupo de trabajo que estudio el problema de disenar de manera optima, una red de distribucion de agua potable. Esencialmente se discuten dos clases de estrategias. En primer lugar, aquellas cuya finalidad es reducir significativamente los recursos computacionales requeridos por los algoritmos im- plementados por el IMTA. Estos algoritmos son de caracter heuristico y generan una solucion factible que no es optima. En ciertos casos se sabe que las soluciones obtenidas por dichos algoritmos estan relativamente lejos del optima y no son aceptables desde el punto de vista del disenador. La segunda clase de estrategias propuestas, esta destinada precisamente a aliviar este problema. Se sugieren tecnicas originadas en optimizacion continua yen flujo en redes
Effect of self-pollination with heat-treated pollen on parthenocarpy and homozygosity in cassava
Cassava\u2019s ( Manihot esculenta Crantz) high heterozygosity
complicates its genetic improvement via selective breeding. Double
haploid (DH) technology can be used to improve the crop\u2019s
heterozygosity, thereby improving the capacity for genetic improvement.
The objective of this study was to evaluate the effect of
self-pollination using heated pollen on pollen tube penetration, fruit
set, seed and haploid embryo development in cassava genotypes for the
production of haploid cassava. Pollen from two cassava genotypes, NASE3
and NASE14, was heated at 40, 50 and 60 oC for 0.5, 1.0 and 2.0 hr
each. The heated pollen was used in six rounds of self-pollinations.
Pollen tube penetration was monitored by fluorescent microscopy,
followed by early embryo rescue and ovule culture. Ploidy and zygosity
were assessed using flow cytometry and single-nucleotide polymorphism
analysis, respectively. Pollen germinated on the stigma, grew within
the style through the nucellar beak, but did not reach the embryo sac,
thus achieving no fertilisation in all the 5756 self-pollinated
flowers. There was a reduction in pollen germination (in vitro and in
vivo), pollen tube penetration and fruit set with increasing
temperature. Heat-treated pollen stimulated division of the egg cell
and induced development of parthenocarpic fruits. Up to 6 embryoids per
ovule were observed and all regenerated plantlets were diploid, with up
to 93.0% increased homozygosity. For the first time, plant regeneration
from ovules, pollinated with fresh pollen at 14 days after pollination,
was achieved indicating improved speed in plant regeneration. The data
generated are important for the development of protocols for cassava DH
plant production.La forte h\ue9t\ue9rozygotie du manioc ( Manihot esculenta
Crantz) complique son am\ue9lioration g\ue9n\ue9tique par
s\ue9lection s\ue9lective. La technologie d\u2018 haplo\uefde
double (DH) peut \ueatre utilis\ue9e pour am\ue9liorer
l\u2019h\ue9t\ue9rozygotie de la culture, am\ue9liorant ainsi la
capacit\ue9 d\u2019am\ue9lioration g\ue9n\ue9tique.
L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer
l\u2019effet de l\u2019auto-pollinisation \ue0 l\u2019aide de
pollen chauff\ue9 sur la p\ue9n\ue9tration du tube pollinique, la
nouaison, le d\ue9veloppement des graines et des embryons
haplo\uefdes dans les g\ue9notypes de manioc pour la production de
manioc haplo\uefde. Le pollen de deux g\ue9notypes de manioc, NASE3
et NASE14, a \ue9t\ue9 chauff\ue9 \ue0 40, 50 et 60 oC pendant
0,5, 1,0 et 2,0 heure (s) chacun. Le pollen chauff\ue9 a
\ue9t\ue9 utilis\ue9 dans six cycles d\u2019auto-pollinisation.
La p\ue9n\ue9tration du tube pollinique a \ue9t\ue9
surveill\ue9e par microscopie fluorescente, suivie d\u2019un
sauvetage pr\ue9coce des embryons et d\u2019une culture
d\u2019ovules. La plo\uefdie et la zygosit\ue9 ont \ue9t\ue9
\ue9valu\ue9es \ue0 l\u2019aide de la cytom\ue9trie en flux et
de l\u2019analyse du polymorphisme mononucl\ue9otidique,
respectivement. Le pollen a germ\ue9 sur le stigmate, s\u2019est
d\ue9velopp\ue9 dans le style \ue0 travers le bec nucellaire,
mais n\u2019a pas atteint le sac embryonnaire, n\u2019obtenant ainsi
aucune f\ue9condation dans toutes les 5756 fleurs autogames. Il y
avait une r\ue9duction de la germination du pollen (in vitro et in
vivo), de la p\ue9n\ue9tration du tube pollinique et de la nouaison
avec l\u2019augmentation de la temp\ue9rature. Le pollen trait\ue9
thermiquement a stimul\ue9 la division de l\u2019ovule et induit le
d\ue9veloppement de fruits parth\ue9nocarpiques. Les 6
embryo\uefdes par ovule ont \ue9t\ue9 observ\ue9s et toutes les
plantules r\ue9g\ue9n\ue9r\ue9es \ue9taient diplo\uefdes,
avec 93,0% d\u2018augmentation d\u2019homozygotie. Pour la
premi\ue8re fois, la r\ue9g\ue9n\ue9ration des plantes \ue0
partir des ovules, pollinis\ue9es avec du pollen frais 14 jours
apr\ue8s la pollinisation, a \ue9t\ue9 r\ue9alis\ue9e,
indiquant une vitesse am\ue9lior\ue9e de
r\ue9g\ue9n\ue9ration des plantes. Les donn\ue9es
g\ue9n\ue9r\ue9es sont importantes pour l\u2019\ue9laboration
de protocoles de production de plantes de manioc de DH
Fruit set and plant regeneration in cassava following interspecific pollination with castor bean
The increasing demand for cassava ( Manihot esculenta Crantz) for
food and non-food uses in the tropics necessitates that its breeding
for increased root productivity be made faster. The characteristic long
breeding cycle and heterozygous nature of this crop, pose a major
obstacle to its rapid genetic improvement. This study aimed at
inter-pollinating cassava with castor bean ( Ricinus communis ), with
a purpose of inducing and regenerating cassava doubled haploids (DHs).
A total of 3,349 flowers from twelve elite cassava varieties were
inter-pollinated with caster bean. A total of 803 fruits were harvested
for early embryo rescue and/or ovule culture. Of these, three were
dissected to obtain seven unique embryos, while 800 were dissected to
obtain 1312 young ovules, all of which were cultured in vitro. Overall,
82 (6.25%) of the cultured ovules formed callus that originated from
the embryosac region, which is haploid. Four out of seven rescued
embryos (57.1%) regenerated into plantlets. Ploidy analyses of 24
samples using flow cytometry revealed that 23 of the analysed samples
were diploid. However, one callus sample was anueploid. Only one sample
had an exceptionally high level of homozygosity ( 84.2%). These
findings lay a foundation for future research aimed at induction of
haploids in cassava.La demande croissante de manioc (\ua0 Manihot esculenta
\ua0Crantz\ua0) \ue0 usage alimentaire et non alimentaire dans
les tropiques\ua0n\ue9cessite que sa reproduction pour une
productivit\ue9 accrue des racines soit faite plus
rapidement.\ua0Le long cycle de reproduction et le caract\ue8re
h\ue9t\ue9rozygote de cette plante constituent un obstacle majeur
dans la rapidit\ue9 de son am\ue9lioration
g\ue9n\ue9tique.\ua0Cette \ue9tude visait \ue0
inter-polliniser le manioc avec le haricot (\ua0 Ricinus communis
\ua0), dans le but d\u2019induire et de r\ue9g\ue9n\ue9rer le
manioc d\u2019haplo\uefdes doubl\ue9 (HD).\ua0Un total de 3 349
fleurs de douze \ue9lites vari\ue9t\ue9s de manioc ont
\ue9t\ue9 inter-pollinis\ue9es avec le haricot.\ua0Un total de
803 fruits ont \ue9t\ue9 r\ue9colt\ue9s pour les embryons
pr\ue9matur\ue9s qui etaient sauves et\ua0/ ou la\ua0culture
d\u2019ovules\ua0.\ua0Parmi ceux-ci,\ua0trois ont \ue9t\ue9
diss\ue9qu\ue9s pour obtenir sept embryons
uniques\ua0,\ua0tandis que 800 ont \ue9t\ue9
diss\ue9qu\ue9s pour obtenir 1312 jeunes ovules, qui ont tous
\ue9t\ue9 cultiv\ue9s\ua0in vitro\ua0.\ua0Un total de 82
(6,25%) des ovules en culture ont form\ue9 des cals provenant de
la\ua0r\ue9gion\ua0embryonnaire\ua0, qui est haplo\uefde.
Quatre parmi sept embryons sauv\ue9s (57,1%) se sont
r\ue9g\ue9n\ue9r\ue9s en plantules.\ua0Les analyses de
plo\uefdie de 24 \ue9chantillons par cytom\ue9trie en flux ont
r\ue9v\ue9l\ue9 que 23 des \ue9chantillons analys\ue9s
\ue9taient diplo\uefdes.Cependant, un \ue9chantillon de cals
\ue9tait anueplo\uefde.\ua0Un seul \ue9chantillon
pr\ue9sentait un niveau d\u2019homozygotie exceptionnellement
\ue9lev\ue9\ua0(84,2\ua0%).\ua0Ces r\ue9sultats sont les
bases des recherches dans le futur sur la cause des haplo\uefdes dans
le manioc
Regeneração in vitro de anteras de arroz irrigado (Oryza sativa L.) e mapeamento de QTL associado
Application of unsupervised chemometric analysis and self-organising feature map (SOFM) for the classification of lighter fuels
A variety of lighter fuel samples from different manufacturers (both unevaporated and evaporated) were analysed using conventional gas chromatography-mass spectrometry (GC-MS) analysis. In total 51 characteristic peaks were selected as variables and subjected to data pre-processing prior to subsequent analysis using unsupervised chemometric analysis (PCA and HCA) and a SOFM artificial neural network. The results obtained revealed that SOFM acted as a powerful means of evaluating and linking degraded ignitable liquid sample data to their parent unevaporated liquids
Ethnobotanical remarks on Central and Southern Italy
<p>Abstract</p> <p>Background</p> <p>The present paper is a brief survey on the ethnobotanical works published by the Authors since 1981, concerning the research carried out in some southern and central Italian regions. Before Roman domination these territories were first inhabited by local people, while the southern areas were colonized by the Greeks. These different cultural contributions left certain traces, both in the toponyms and in the vernacular names of the plants and, more generally, in the culture as a whole.</p> <p>Methods</p> <p>Field data were collected through open interviews, mainly of farmers, shepherds and elderly people, born or living in these areas for a long time. Voucher specimens of collected plants are preserved in the respective herbaria of the Authors and in the herbarium of "Roma Tre" University. Important contributions have been made by several students native to the areas under consideration. A comparative analysis with local specific ethnobotanical literature was carried out.</p> <p>Results</p> <p>The paper reports several examples concerning human and veterinary popular medicine and in addition some anti-parasitic, nutraceutic, dye and miscellaneous uses are also described. Moreover vernacular names and toponyms are cited. Eight regions of central and southern Italy (particularly Latium, Abruzzo, Marche and Basilicata) were investigated and the data obtained are presented in 32 papers. Most of the species of ethnobotanical interest have been listed in Latium (368 species), Marche (274) and Abruzzo (203). The paper also highlights particularly interesting aspects or uses not previously described in the specific ethnobotanical literature.</p> <p>Conclusion</p> <p>Phyto-therapy in central and southern Italy is nowadays practised by a few elderly people who resort to medicinal plants only for mild complaints (on the contrary food uses are still commonly practised). Nowadays therapeutic uses, unlike in the past, are less closely or not at all linked to ritual aspects. Several plants deserve to be taken into consideration not only from the anthropological or cultural point of view, but also for further phyto-chemical investigation. Our studies, as well as those of other authors, try to provide an original picture of the local ethno-biodiversity.</p
Wild vascular plants gathered for consumption in the Polish countryside: a review
BACKGROUND: This paper is an ethnobotanical review of wild edible plants gathered for consumption from the end of the 18(th )century to the present day, within the present borders of Poland. METHODS: 42 ethnographic and botanical sources documenting the culinary use of wild plants were analyzed. RESULTS: The use of 112 species (3.7% of the flora) has been recorded. Only half of them have been used since the 1960s. Three species: Cirsium rivulare, Euphorbia peplus and Scirpus sylvaticus have never before been reported as edible by ethnobotanical literature. The list of wild edible plants which are still commonly gathered includes only two green vegetables (Rumex acetosa leaves for soups and Oxalis acetosella as children's snack), 15 folk species of fruits and seeds (Crataegus spp., Corylus avellana, Fagus sylvatica, Fragaria vesca, Malus domestica, Prunus spinosa, Pyrus spp., Rosa canina, Rubus idaeus, Rubus sect. Rubus, Sambucus nigra, Vaccinium myrtillus, V. oxycoccos, V. uliginosum, V. vitis-idaea) and four taxa used for seasoning or as preservatives (Armoracia rusticana root and leaves, Carum carvi seeds, Juniperus communis pseudo-fruits and Quercus spp. leaves). The use of other species is either forgotten or very rare. In the past, several species were used for food in times of scarcity, most commonly Chenopodium album, Urtica dioica, U. urens, Elymus repens, Oxalis acetosella and Cirsium spp., but now the use of wild plants is mainly restricted to raw consumption or making juices, jams, wines and other preserves. The history of the gradual disappearance of the original barszcz, Heracleum sphondylium soup, from Polish cuisine has been researched in detail and two, previously unpublished, instances of its use in the 20(th )century have been found in the Carpathians. An increase in the culinary use of some wild plants due to media publications can be observed. CONCLUSION: Poland can be characterized as a country where the traditions of culinary use of wild plants became impoverished very early, compared to some parts of southern Europe. The present use of wild plants, even among the oldest generation, has been almost entirely restricted to fruits
Tanshinones Inhibit the Growth of Breast Cancer Cells through Epigenetic Modification of Aurora A Expression and Function
The objectives of this study were to evaluate the effects of tanshinones from a Chinese herb Salvia Miltiorrhiza on the growth of breast cancer cells, and to elucidate cellular and molecular mechanisms of action. Tanshinones showed the dose-dependent effect on the growth inhibition of breast cancer cells in vitro, with tanshinone I (T1) the most potent agent. T1 was also the only tanshinone to have potent activity in inhibiting the growth of the triple-negative breast cancer cell line MDA-MB231. T1 caused cell cycle arrests of both estrogen-dependent and estrogen-independent cell lines associated with alterations of cyclinD, CDK4 and cyclinB, and induced breast cancer cell apoptosis associated with upregulation of c-PARP and downregulation of survivin and Aurora A. Among these associated biomarkers, Aurora A showed the most consistent pattern with the anti-growth activity of tanshinones. Overexpression of Aurora A was also verified in breast tumors. The gene function assay showed that knockdown of Aurora A by siRNA dramatically reduced the growth-inhibition and apoptosis-induction activities of T1, suggesting Aurora A as an important functional target of T1 action. On the other hand, tanshinones had much less adverse effects on normal mammary epithelial cells. Epigenetic mechanism studies showed that overexpression of Aurora A gene in breast cancer cells was not regulated by gene promoter DNA methylation, but by histone acetylation. T1 treatment significantly reduced acetylation levels of histone H3 associated with Aurora A gene. Our results supported the potent activity of T1 in inhibiting the growth of breast cancer cells in vitro in part by downregulation of Aurora A gene function. Our previous studies also demonstrated that T1 had potent anti-angiogenesis activity and minimal side effects in vivo. Altogether, this study warrants further investigation to develop T1 as an effective and safe agent for the therapy and prevention of breast cancer
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