Browsing by Issue Date, starting with "2005-01"
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- Reproductive cycle of Leptaxis caldeirarum, a locally endangered Azorean land snailPublication . Rodrigues, Armindo; Medeiros, JorgeThe land snail Leptaxis caldeirarum (Morelet and Drouet, 1857), a hermaphrodite Hygromiidae species, endemic from São Miguel Island (Azores), is geographically limited to a range of 31 km2, occupying an area of about 14 km2. A preliminary study confirmed the locally endangered status of the species, raising the possibility that it could reach the “critically in danger” status, the most serious category in IUCN. A population from Ramal dos Mosteiros was studied all year round in order to elucidate its reproductive cycle and to test the validity of the total weight of the animal and the maximum diameter of the shell as diagnostic parameters for maturation. Gonadal maturation of L. caldeirarum proceeds from late winter to early summer. Intense gametogenesis takes place from January until May and the snail is apparently in a reproductive condition to copulate from late spring onwards. The strong correlation observed between the relative volumetric density of mature gametes and the maximum diameter of the shell suggests that the reproductive status of the species can be inferred from the latter parameter. This may be of major importance in future studies, minimizing potential damage to already unstable populations, and facilitating the development of conservation strategies.
- Equalization effects of local financing models in PortugalPublication . Fortuna, Mário; Vieira, José Cabral; Mendes, MargaridaOne objective frequently found in models of decentralized financing is that of equalization. The concern is that poorer jurisdictions receive enough resources for basic services and for development promotion, thus eliminating horizontal and vertical imbalances. In Portugal, decentralization has occurred at two levels: the local, for the whole country and the regional for the autonomous regions of the Azores and Madeira. Decentralization to local governments has undergone several changes in recent decades. The current paper focuses on testing for the presence of an equalization effect in the models adopted to finance municipalities in Portugal, since the nineteen nineties. Using the theoretical background that maintains that for the presence of an equalizing effect it is necessary that, on a per capita basis, poorer regions or localities receive relatively more transfers than the richer jurisdictions, a test is made using a data set that includes all municipalities of Portugal. The situation of the two autonomous regions is controlled with dummy variables. The hypothesis that the models used have an equalizing effect is tested through the sign of the coefficient of the regression of per capita transfers on per capita own resources. In the presence of an equalizing effect the sign will be significant and negative. It is confirmed that, for the period under analysis, the municipalities with lower per capita own revenues are those that receive more transfers per capita. There is, therefore, an equalizing effect in the current transfer system to municipalities. Using pooled data, one can also conclude that the equalization effect has become stronger with the 1998 and 2002 reviews of the system, when compared to the system in effect in 1991.
- The effects of supplementation with sunflower and soybean oils on the fatty acid profile of milk fat from grazing dairy cowsPublication . Rego, Oldemiro Aguiar do; Rosa, Henrique José Duarte; Portugal, Paula V.; Franco, Tiago; Vouzela, Carlos Fernando Mimoso; Borba, Alfredo Emílio Silveira de; Bessa, Rui José B.The objective of this study was to observe the effect of supplementation with vegetable oils (VO) on the fatty acid profiles and conjugated linoleic acid (CLA) content of milk fat. Twelve dairy cows in mid lactation fed on pasture were blocked by body weight, milk production and days in lactation and randomly allocated from blocks to 3 treatments repeated in a Latin square design with periods of 28 day duration. The treatments were as follows: cows on pasture supplemented with 5 kg concentrate per head per day (C), supplemented with 4.5 kg concentrate + 0.5 kg sunflower oil per head per day (SFO) and supplemented with 4.5 kg concentrate + 0.5 kg soybean oil per head per day (SBO). The animals were grazed as a group and were stocked at 2.5 heads per hectare. The treatments had no effect on milk yield or protein yield and content, but decreased milk fat yield and content (P < 0.05). Milk fat from the cows supplemented with VO had a lower concentration of short and medium chain fatty acids (P < 0.05) and a higher concentration of long chain fatty acids (P < 0.05). The addition of VO to the diet also resulted in a reduction in saturated and an increase in unsaturated fatty acids of milk fat (P < 0.05). The hypercholesterolemic fatty acids in milk fat (i.e. C12:0, C14:0 and C16:0) decreased while the concentration of oleic and linoleic acids increased with VO (P < 0.05). There was no effect on linolenic acid. Finally, the inclusion of VO in the diet increased (P < 0.05) the contents in milk fat of the various cis/trans isomers of oleic acid (including trans-vacenic, TVA) and of CLA which increased by 61%.
- An azorean dairy farms typologyPublication . Silva, Emiliana; Barbel, JulioThe objective of this paper was to define types of Azorean farms from a panel data of 174 farms of The European database of Farm Accountancy Data Network of the Azores, Portugal. This study used cluster analysis, the Ward method. The results, allowed the identification of three types of grazing systems of dairy farms as follows: 1) extensive grazing systems (less than smaller 1.4 cows per hectare); 2) moderate intensive grazing system (1.4 to 2.4 cows per hectare); and 3) intensive grazing system (more than 2.4 cows per hectare).
- The correlation of transport properties of alkali metal vapours and noble gases.Publication . Apelblat, Alexander; Fialho, Paulo; Nieto de Castro, Carlos A.It was found that transport properties of gases (viscosity η, thermal conductivity λ, and diffusion coefficients D) in the form of the quantity: C = ηD λT α are temperature independent in the 700–2000K temperature interval. Although the exponent α seems to be independent inside the group for all the monoatomic vapours it seems to change between different groups (α = 1.909±0.015 for alkali metal vapours – Li, Na, K, Rb and Cs; α = 1.72±0.05 for noble gases – He, Ne, Ar, Kr, and Xe). In this approach, transport properties of gases are correlated using only different values of C. This fact was extended to the properties of the binary mixtures of monoatomic and diatomic molecules in the alkali metal vapours, to obtain the mutual diffusion coefficients D12(T, p) and the self-diffusion coefficients of diatomic molecules, D22(T).
- Metodologia para avaliar as atitudes face ao ambientePublication . Gabriel, Rosalina; Silva, EmilianaNeste trabalho apresentam-se algumas metodologias utilizadas para estimar as atitudes da população face ao ambiente, nomeadamente as que se referem ao Novo Paradigma Ambiental (NPA). Apresentam-se ainda os resultados de um inquérito piloto acerca das atitudes ambientais, efectuado em Julho de 2004 a 47 habitantes da freguesia da Terra Chã (Ilha Terceira, Açores). Este inquérito usa a escala original do Novo Paradigma Ambiental e inclui ainda questões relacionadas com recursos hídricos, resíduos sólidos e biodiversidade. A escala utilizada parece ser fiável (alfa de Cronbach = 0.75) e a análise de agrupamentos de Ward mostra que os items da escala do NPA relativos à conservação e ao equilíbrio da natureza formam grupos coerentes, tal como tem sido mostrado noutros estudos. Os resultados do inquérito mostram que a maioria da população inquirida se insere dentro dos valores do NPA, sobretudo os mais jovens e com maior nível de escolaridade.