Copulatory behaviour and differential reproduction of laboratory rats in a two-male,one-female competitive situation

In order to relate copulatory behaviour to differential reproductiion, 20 Long-Evans and 20 F344 male rats were observed in both one-male and two-male tests with an F344 female. Copulatory behaviour was quite similar in the two conditions, although there were some quantitative differences. Little fighting occurred. Long-Evans males attained 56% of the ejaculations and sired 76% of the offspring. The first male to ejaculate gained no advantage with respect to siring offspring. By contrast, the male ejaculating last or most frequently gained a significant reproductive advantage. Far from being wasted activity, persistent copulation in male rats plays an integral role in differential reproduction.     

Neuroparacoccidioidomycosis: Case reports and review

Cerebral and cerebellar masses occurred in patients with paracoccidioidomycosis. Correct diagnosis was delayed due to overlooking the abnormal lung roentgenograms and the history of previous disease in a different localization. The fungus was identified through biopsy and direct examination of the samples. In two patients necropsy confirmed the diagnosis. None of the patients responded to amphotericin B or cotrimoxazole. A 10 year English and Latin American literature review on neuroparacoccidioidomycosis was performed through a MEDLINE and LILACS (Latin American Literature Search System) data base systems.     

C9orf72 regulates energy homeostasis by stabilizing mitochondrial complex I assembly

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Assessment of variability in biomass yield and quality: what is an adequate size of sampling area for miscanthus?

To diversify energy crop production and improve its biodiversity and sustainability, there is currently a search for alternative energy crops. Many of the newly arising alternatives are perennial species such as the C₄ grass miscanthus. The assessment of reliable data is a prerequisite for understanding the performance of these crops and developing corresponding management systems. However there is great uncertainty concerning research methodology for these crops. When data are collected from small plots of perennial crops, such as miscanthus or short rotation coppice plantations, a larger variability is expected than for cereals. A square meter cut, corresponding to harvest practice in cereals, is not sufficient for perennial C₄ grasses and is not recommended for these species. The aim of this research was to identify an adequate size of sampling area for miscanthus to estimate the true biomass yield or quality. For this purpose, whole plots of 10‐ and 14‐year old miscanthus stands were divided into smaller subplots. These were used to calculate variances for various sizes of simulated plots. The variances for all traits in the experiments were rather high when the sampling area was smaller than 2 m². A cutting regime of more than 5.6 m² would be advisable, but an area of 3 m² is sufficient to eliminate approximately 90% of the variances and is therefore an adequate size of sampling area.     

Transport, synthesis and catabolism of abscisic acid (ABA) in intact plants of castor bean (Ricinus communis L.) under phosphate deficiency and moderate salinity

Flows of abscisic acid (ABA) were investigated in whole plantsof castor bean (Ricinus communis) grown in sand culture undereither phosphate deficiency or moderate salinity. Xylem transportof ABA in P-deficient plants was stimulated by a factor of 6whereas phloem transport was affected only very slightly. ABAdeposition into leaves of P-deficient plants was not appreciablydifferent from the controls because of strong net degradationin leaves. Since conjugation of ABA was strongly reduced inall organs of P-deficient plants ABA was presumably metabolizedmainly to phaseic acid and dihydrophaseic acid. The increasedimport of ABA occurred predominantly into fully differentiatedbut not senescent leaves and showed a good correlation withthe inhibition of leaf conductance under P deficiency. As with low-P-plants salt stress increased ABA synthesis inroots and associated transport in the xylem. However, salinitycaused a distinctly greater accumulation of ABA in the leaves,stem segments and the apex than in P-deficient plants. As opposedto P deficiency, ABA export in the phloem from the leaves wasstimulated by salinity. Modelling of ABA flows within an individualleaf over its life cycle showed that young growing leaves importedABA from both phloem and xylem, whereas the adult non-senescentleaves were a source of ABA and thus provided a potential shoot-to-rootstress signal as well as an acceptor for reciprocal signalsfrom root to shoot. In senescing leaves ABA flows and accumulationwere somewhat retarded and ABA was lost in net terms by exportfrom the leaf. Key words: Abscisic acid, phosphorus deficiency, salt stress, phloem and xylem transport     

Transportation in LCA

The purpose of this paper is to investigate whether transport and logistics substantially contribute to the environmental interventions and impacts identified in LCAs. Four LCAs, encompassing very different products in different countries, were screened for the relative contribution of transport to the overall environmental interventions and impacts. Aside from this, the contribution of transport within individual life cycle phases was investigated. In none of the LCAs did transport contribute to less than 5% of the energy related interventions or impacts, whereas contributions with more than ten percent occurred regularly, especially in events involving NO_x related impact. The importance of transport strongly depends on the kind of product studied. It seems to be especially important for agricultural products. With respect to individual phases of the life cycle, the study indicates that special attention is required for the transport of raw materials, for use phase of electronics and for the disposal phase of recyclable products.