Rediscovery of Eremobittacus spinulatus Byers (Mecoptera,Bittacidae) in Mexico,with description of the female and comments on sexual dimorphism and potential mimicry

The female of Eremobittacus spinulatus Byers, 1997 is described for the first time. A key to the two species known of this genus endemic to Mexico is provided, and species distribution is illustrated. A case is made for adults of Eremobittacus to be sexually dimorphic, which appears to be an exceptional occurrence in Bittacidae. It is claimed that Eremobittacus spinulatus habitus has a wasp-like appearance, which may potentially depict a case of mimicry.     

Male-female interactions in Drosophila melanogaster: model with one-locus and three-alleles

We develop a fertility model of fitness that is general in that it does not assume that the fitnesses of the mating combinations are symmetrical or that they are additive or multilicative (i. e., that they can be inferred from fitnesses of the two genotypes involved in a mating). %he model considers one locus with three alleles. An experimental test with Drosophila rnelanogaster confirms that the fitnesses of the mating types depart from both additivity (or multiplicativity) and symmetry although this last property is of no consequence for the development of analytical models). urnerical simulations yield the same, or very nearly the same, equilibrium freuencies as the analytical model, independently of whether or not Hardy-Weinberg equilibrium Trequencies are assumed at the beginning of each selection cycle.     

Nasal provocation test with histamine: rhinomanometry study of normal subjects

Nasal reactivity to histamine was evaluated in 40 normal subjects. The application of a chloride histamine solution (1 mg) registered in 90% of the subjects the appearance of sneezing with the number of sneezes ranging between one and fourteen (5.7 +/- 3.76) and an average increase in the total resistence in the inspiration phase of 93.1% (+/- 63.2) and in the expiration phase of 98.1% (+/- 60.5) with a range between 37.7% and 24.1%. The authors conclude that sneezing and above all nasal congestion evaluated rhinomanometrically represent two important parameters in the evaluation of nasal reaction; an increase greater than or equal to 200% of the total nasal resistance can surely be considered an index of nasal hyperreactivity.     

Influence of enzyme supplementation of diets and cooking–flaking of maize on digestive traits and growth performance of broilers from 1 to 21 days of age

A trial was conducted to study the influence of cooking–flaking (C-F) of maize and enzyme supplementation (ES) of the diet on mucosa morphometry, digestive organ weight, dietary component digestibility and growth performance of broilers from 1 to 21 days of age. There were 4 treatments arranged factorially with 2 heat processings of maize (raw and C-F) and 2 levels (0 and 500 mg/kg) of an enzyme complex with xylanase, protease and α-amylase activity. Dietary treatment did not affect any productive trait from 1 to 21 days of age. However, from 1 to 4 days of age, body weight gain (P<0.01) and feed conversion ratio (P<0.001) were improved by ES of the diet. Intestinal viscosity increased with C-F of maize and decreased with ES of the diet (P<0.001). The effects of ES on intestinal viscosity were more pronounced with C-F than with raw maize (P<0.001) and at younger than older ages (P<0.05). Cooking–flaking of maize increased total tract apparent digestibility of dry matter and organic matter (P<0.05) and of neutral detergent fibre and starch (P<0.001) and tended to improve ether extract (EE) digestibility (P<0.10). In addition, ES improved nitrogen retention (P<0.01) and EE digestibility (P<0.001). Digestibility of neutral detergent fibre and starch increased linearly (P<0.001) with age whereas nitrogen retention and organic matter, EE and gross energy digestibility decreased from 4 to 8 days of age and increased thereafter (P<0.001). The relative weight (g/kg body weight) of the pancreas decreased (P<0.01) and that of the liver increased (P<0.001) with C-F of maize. The relative weight of the proventriculus, gizzard and liver reached a maximum before 6 days of age and that of the small intestine and pancreas at approximately 7.8 days of age (P<0.001). Enzymes increased villus height (P<0.05) but did not affect villus width or villus surface area. It is concluded that C-F of maize improved dietary component digestibility but had no effect on broiler performance at 21 days of age. In addition, ES improved nitrogen retention, EE digestibility and productive performance of broilers but only from 1 to 4 days of age.     

Differences between airborne pollen and flowering phenology of urban trees with reference to production, dispersal and interannual climate variability

Annual totals of daily arboreal pollen concentrations were analysed in Mar del Plata (Argentina) during 1993 and 1994. Flowering patterns were associated with timing and intensity of pollen appearing in the air. Seasonal climatic parameters before the start of flowering and current weather conditions during dispersion were considered.Flowering showed a regular pattern between years and it could be defined by cumulated pollen percentages. Arboreal pollen counts were higher in the first year and is probably due to 1) better climatic conditions connected with pollen productivity and 2) lower precipitation after pollen emission. Betula and Q. ilex showed an opposite behaviour that appears to be caused by a biennial fluctuating rhythm of pollen production.