1,255 research outputs found

    La vegetazione dell\u2019istituenda Riserva Naturale \u201cOasi di Lacchiarella\u201d (Parco Agricolo Sud Milano).

    Get PDF
    \uc8 stata studiata dal punto di vista fitosociologico la vegetazione della Riserva naturale Oasi di Lacchiarella. Sono state individuate 34 cenosi vegetali, ascrivibili a 12 classi fitosociologiche: Lemnetea, Potametea, Phragmiti-Magnocaricetea, Bidentetea tripartiti, Stellarietea mediae, Oryzetea sativae, Molinio- Arrhenatheretea,Galio-Urticetea, Alnetea glutinosae, Salicetea purpureae, Rhamno-Prunetea e Querco-Fagetea. Il grado di naturalit\ue0 e il valore floristico-vegetazionale \ue8 nel complesso basso, anche nelle formazioni boschive. Le cenosi si dispongono secondo un gradiente ecologico di umidit\ue0, caratterizzato da un progressivo svincolamento dalla falda. Le cenosi di piante infestanti o ruderali seguono una propria linea dinamico-evolutiva, pressoch\ue9 indipendente da quella di interramento dei corsi d\u2019acqua; entrambe comunque convergono verso le formazioni boschive

    Cultura do girassol: tecnologia de produção.

    Get PDF
    Escolha da area e preparo do solo; Correcao da acidez; Adubacao; Epoca de plantio; Plantio; Densidade; Controle de plantas daninhas; Doencas e pragas; Colheita.bitstream/item/60796/1/Documentos-67.pd

    Cultura do girassol: tecnologia de produção.

    Get PDF
    Escolha de area e preparo do solo; Correcao da acidez; Adubacao; Epoca de plantio; Plantio; Densidade; Controle de plantas daninhas; Doencas e pragas; Colheita.bitstream/item/61288/1/Documentos-67-1996.pdf2. ed. rev. aum

    Análise da capacidade combinatória entre linhagens de girassol.

    Get PDF
    A capacidade geral (CGC) e a capacidade específica de combinação (CEC), entre duas linhagens macho-estéreis (mãe) e um grupo de sete linhagens S4 restauradoras de fertilidade (pai), foram estimadas para estudar o potencial desses materiais em programas de melhoramento de girassol (Helianthus annuus L.). O método IV de Griffing, adaptado para cruzamentos dialélicos parciais, foi usado na análise das combinações híbridas. Considerando a CGC para rendimento de aquênios e teor de óleo, os progenitores com maior potencial para o melhoramento foram CMS HA 302 (originária de uma população norte-americana) para ser usada como mãe, e as linhagens 89V2345)3382 e 89V2345)3311 (derivadas da população V2000, obtida por seleção sobre a população Issanka, originária da França) como pais nos cruzamentos. Para o rendimento de aquênios, os efeitos gênicos não aditivos foram importantes na determinação das diferenças entre progenitores. Considerando-se os efeitos gênicos aditivos e não-aditivos conjuntamente, as melhores combinações são CMS HA 302 x 89V2396)5333 para rendimento de aquênios e CMS HA 30379NW22 x 89V2345)3382 para teor de óleo e rendimento de óleo

    Hybrid manufacturing of steel construction parts via arc welding of LPBF-produced and hot-rolled stainless steels

    Get PDF
    The demand for free-form steel structures having improved performances, reducing labour and resource usage is increasing in the construction sector. Structural nodes are some of the most critical regions for steel structures characterised often by large dimensions. These nodes can exploit the geometrical freedom of metal additive manufacturing (MAM) processes. Laser powder bed fusion (LPBF) is arguably the most developed MAM process, which has limitations regarding the size of the parts to be produced. A way to overcome the size limits of LPBF for producing structural nodes while still exploiting its geometrical capacity is producing hybrid components by welding them to traditionally manufactured beams. Such hybrid joints would constitute a complex system from a mechanical design perspective requiring a systematic analysis in order to be certified for structural use. Accordingly, this work studies the mechanical behaviour of hybrid steel components generated by welding LPBF plates and quarto plates made of AISI 316L stainless steel. The work was guided by a case study based on a large steel node, which helped defining the requirements to fill the gap of the international standards. The mechanical characterisation of LPBF-produced plates and quarto plates, as well as the welded hybrid components revealed a maximum of 10% difference between the properties of the differently manufactured plates. Through the digital image correlation (DIC) analyses, the anisotropic deformation behaviour along the LPBF, weld seam, and quarto plate regions have been identified, and the properties after welding did not show relevant modifications. The tests allowed to define that the failure behaviour is mainly governed by interlayer bounds, and a 0.9 safety reduction parameter for considering the reduction of ductility induced by arc welding to LPBF. Finally, design and production suggestions have been provided for a correct evaluation of gross and effective sections of the designed nodes

    Analysis of 22 mutations within milk protein genes in Italian Friesian cattle

    Get PDF
    The bovine milk protein caseins, αS1-CN, β-CN, αS2-CN, and κ-CN are codified by four well characterized genes, named CSN1S1, CSN2, CSN1S2, and CSN3 respectively and clustered in a region of 250-kb of chromosome 6. A recent revision of milk protein nomenclature considering only protein polymorphisms indicates 8 αS1-CN, 4 αS2-CN, 12 β-CN, and 11 κ-CN variants within the genus Bos. Other mutations were found in the non-coding regions of the cluster, such as the promoter regions or the 3'UTR. Many of these polymorphisms, together with others in various genes, such as the one coding for β-lactoglobulin (LGB), show important associations with different milk quality traits. Analyzing all these polymorphisms could help clarify the role of both the casein haplotype and the other polymorphisms in milk composition and cheese-making properties, and could explain which polymorphisms are really or mostly involved. The mPCR-LDR-UA approach recently developed to test simultaneously 22 SNPs in DNA regions responsible for milk protein expression was used to type 250 Italian Friesian cattle. In perfect agreement with literature, the most frequent alleles were CSN1S1*B, CSN2*A2, CSN3*A, variant 2 of CSN1S1 promoter, and variant A of Bov-A2 element. A quite balanced frequency was observed for the LGB*A and LGB*B. No CSN2*C, CSN3*C, and CSN3*H alleles were found. The CSN1S1*C, CSN2*A3, CSN2*I alleles were detected only at the heterozygous condition and at a frequency lower than 2%. The method allowed also finding some unusual intragenic haplotype, such as the Bov-A2 element-CSN3 haplotypes A-B and B-E. As to LGB one of the four SNPs tested was always homozygous for the same mutation, as already noticed. This finding confirms that this synonymous SNP is probably a sequencing mistake or a rare mutation not decisive for the LGB typing in the Italian Friesian. Reducing cost and time for typing simultaneously many SNPs, the method will be applied to a greater number of individuals and to other breeds, aiming to find out a number of animals for each haplotype sufficient for accurate statistical analysis to give a better understanding of the significance of milk protein polymorphism
    corecore