A transient species of poly(A)+ RNA detected by a myosin heavy chain cDNA probe in muscle cell culture during terminal differentiation

Primary cell cultures were prepared from breast muscles of 11 day 4 hour-embryonic chicks. Cytoplasmic RNAs were isolated from the cultured cells at various time intervals from day 3 to day 8. A [P32] DNA probe complementary to messenger RNA of myosin heavy chain was used to hybridize with the RNAs after gel electrophoresis. A transient species of polyadenylated RNA with a decreased mobility in electrophoresis was detected during a period of time when contractions of syncytial fibers were first observed.     

Post-translational heterogeneity of the human vitamin D-binding protein (group-specific component)

The vitamin D-binding protein in human serum (the group-specific component) is an alpha 2-globulin which is genetically polymorphic in all populations studied. Previous work (J. Svasti and B. H. Bowman (1978) J. Biol. Chem. 253, 5188-5194, and J. Svasti, A. Kurosky, A. Bennett, and B. H. Bowman (1979) Biochemistry 18, 1611-1617) has shown that the electrophoretic variations of the proteins controlled by two allelic genes, Gc1 and Gc2, are due to at least three amino acid substitutions between Gc1 and Gc2 (Svasti et al. (1979] and to heterogeneity in the Gc1 phenotype arising from carbohydrate dissimilarities. Gc1 migrates electrophoretically as two protein bands, while Gc2 migrates cathodally as a single band. This study demonstrates a post-translational glycosylation difference occurring in a single area of the Gc1 sequence which accounts for the heterogeneity observed previously. The glycosylation site, a threonine residue, appears to be in a sequence which differs between Gc1 and Gc2. The O-glycosidic bond, which is typical of mucins, is rare in plasma proteins. The cyanogen bromide fragment containing the galactosamine-containing carbohydrate in Gc1 was partially sequenced through 20 residues from the amino terminus. No detectable galactosamine could be found in the homologous cyanogen bromide fragment in Gc2. A new purification procedure for the vitamin D-binding protein in human plasma has been developed. Three chromatographic steps provide purified protein.     

Gender identification of shovelnose sturgeon using ultrasonic and endoscopic imagery and the application of the method to the pallid sturgeon

Monthly sampling of shovelnose sturgeon Scaphirhynchus platorynchus , a biological surrogate for the endangered pallid sturgeon Scaphirhynchus albus , was conducted to develop a multi‐seasonal profile of reproductive stages. Data collected included histological characteristics of gonads from wild caught fish and laboratory and field ultrasonic and endoscopic images. These data were used to compare effectiveness of ultrasonic and endoscopic techniques at identifying gender of adult shovelnose sturgeon at different reproductive stages. The least invasive method ( i.e . ultrasound) was least effective while the most invasive ( i.e . endoscope through an abdominal incision) was the most effective at identifying shovelnose sturgeon gender. In most cases, success rate for identifying males was greater than females, with success at identifying both genders greater in more advanced reproductive stages. Concomitantly, for most months average reproductive stage was more advanced for males than females. April and May were the months with the most advanced reproductive stage, and were the months when ultrasound was most effective. Methods were also applied in the Upper Missouri River to validate their use on pallid sturgeon Scaphirhynchus albus . Ultrasound was successful at identifying pallid sturgeon gender, however, endoscopic examination through the urogenital duct was only successful at identifying pallid sturgeon gender when the urogenital duct was not opaque.     

Physical and chemical variability in sugarcane fields infested with the red-striped soft scale insect,Pulvinaria Tenuivalvata (Newstead)

The red-striped soft scale insect Pulvinaria tenuivalvata (Newstead) (Hemiptera: Coccidae) started to infest sugarcane plants (Saccharum officinarum L.) in different districts in Egypt during the last decade. The percentage of infestation was recorded in El-Wakf area, Qena Governorate (Naghhamadi mill zone) Upper Egypt in some fields. There are three levels of infestation, low, intermediate and high. From these fields, samples were selected for physical and chemical studies. The results obtained show that the stalks of infested plants decreased in weight, the sugar content (glucose and sucrose) drastically reduced and as the percentage of infestation increased the percentage of glucose and sucrose content significantly decreased. The primary and secondary humidity and the cellulose content also increased in the healthy plants compared to the infested ones. All the physical character of the infested plants was significantly affected in comparison with the healthy ones.     

Dynamics and management of some coastal dune woodlands near The Hague,The Netherlands

Changes are reported of Crataegus-Betula dune woodlands between 1950–1980 from Meijendel, a calcareous coastal dune system near the city of The Hague, The Netherlands, which is used as a water catchment area. It concerns both woodlands in degradation stage and, more common, woodlands on the increase. Changes were recorded with help of successive vegetation maps, air photos and permanent plot observations. Woodland increase usually occurs on places with groundwater at or near the surface, either because of natural circumstances or as a result of artificial groundwater recharge through infiltration as part of the water catchment activities. The management of both types of woodland is discussed.Nomenclature follows Heukels-van der Meijden (1983), Flora van Nederland, 20th ed. Wolters-Noordhoff, Groningen. Nomenclature of mosses follows Margadant & During (1982), Beknopte Flora van Nederlandse Blad- en Levermossen, Thieme, Zutphen.The authors have pleasure in thanking their colleagues from the Dune Water Works who supplied data on hydrology.     

The structure of 180° supernumerary limbs and a hypothesis of their formation

The results of a detailed analysis of 100 supernumerary limbs generated by 180° ipsilateral rotation (on the same limb stump) of regeneration blastemas is presented. The limbs were analyzed in terms of their position of origin, frequency, cartilage structure by Victoria blue staining, and muscle structure by serial sections. Single, double, or triple supernumeraries can be produced at no unique position of origin, although the posterodorsal quadrant was preferred. Four classes of supernumerary limbs were generated by such operations—normal; double dorsal or double ventral; part normal/part mirror imaged; part normal/part inverted in approximately equal frequencies. After amputation of these supernumeraries the same muscle patterns are faithfully regenerated. A hypothesis to explain the production of these abnormal limbs is proposed based on the observed phenomenon of fusion of supernumerary blastemata, but their regenerative behaviour presents problems for current models of pattern formation. Similar results have been obtained with developing limb buds and the relation between development and regeneration is discussed.     

Village trial of bednets impregnated with wash-resistant permethrin compared with other pyrethroid formulations

Abstract. A village-scale field trial of pyrethroid-impregnated mosquito nets was undertaken in The Gambia, West Africa, in the Mandinka village of Saruja (13^o13'N, 14^o55'W) during July-November 1989. Nearly all the villagers possessed and used their own bednets. Anopheles gambiae is the main vector of human malaria in the area.
An experimental wash-resistant formulation of permethrin was compared with standard emulsifiable concentrate (EC) formulations of permethrin and lambda-cyhalothrin, versus placebo-treated bednets. Target concentrations of pyrethroids on bednets were permethrin 500mg/m² and lambda-cyhalothrin 25 mg/m². The experimental design involved random allocation of a treatment to one net per family. Whereas 68% of people questioned said they washed their nets fortnightly, observations during the 16-week trial period showed that only 4/130 (3%) of nets involved in the trial had been washed as frequently as once per month.
Early morning searches for mosquitoes under bednets (1 day/week for 16 weeks) found significantly more mosquitoes (60% An. gambiae ) in placebo-treated nets than in pyrethroid-treated nets. The numbers found with each of the three pyrethroid treatments did not differ significantly from each other. Insecticidal efficacy of the treatments was tested by bioassays using wild-caught unfed mosquitoes exposed to netting for 3min. Linear regression analysis of bioassay mortality against number of times that a net had been washed by villagers showed that nets impregnated with the wash-resistant permethrin retained their insecticidal properties better than nets impregnated with lambda-cyhalothrin or with the standard permethrin formulation.     

A semiautomated fluorometric determination of 5-hydroxyindoles in the nanogram range

Automated determinations of 5-hydroxytryptamine and its main metabolite, 5-hydroxyindoleacetic acid, have been described (Technicon autoanalyzer). The determinations are based on an extraction procedure from deproteinized tissue extracts or cerebrospinal fluid by means of butanolheptane mixtures. The indoles are transferred from the organic phase to a water phase and determined fluormetrically with the cysteine-o-phthaldialdehyde method. The method is highly sensitive: solutions containing 1 ng/ml can be reproducibly determined. Twenty samples per hour can be passed through the system. The determination of both 5-hydroxyindoles is performed with the same manifold.     

Village Drift and Riverine Settlement: Modeling Akimel O'odham Land Use

Regular unscheduled movements of rancherías within a confined area or settlement district result in the phenomenon described as "village drift," a process whereby a settlement may change its location gradually by several kilometers over a period of years. This article presents a model of village drift based on data acquired from recent archaeological and geomorphological field studies and archival research on the Akimel O'odham, the Gila River Pima of south-central Arizona. The model provides an excellent example of human ecodynamics---an emerging landscape perspective that emphasizes the coevolution of humans and their ecosystem---with implications for understanding prehistoric and historic settlement in desert riverine environments.     

Linear and non-linear regression analysis of genotype X environment interactions in pearl millet

Summary Regression analysis was computed on the grain yield of 15 single cross F₁ hybrids of pearl millet (Pennisetum typhoides (Burm.) S. & H.) evaluated in 20 environments at 19 sites in India to assess the nature of genotype X environment interactions. Linear, quadratic, cubic, twoand three-intersecting straight line models were examined for fit. The interactions of six hybrids viz. MH 110, MH 113, MH 114, MH 115, MH 120 and MBH 110 were explained by the linear regression model. The response of the remaining nine hybrids was largely non-linear. The two and three-intersecting straight line models fit better than the quadratic and cubic models and explained non-linearity of response. The two-intersecting straight line models fit for 6 hybrids MH 106, MH 107, MH 112, MH 116, MH 117 and BJ 104. The response of MH 109 was best explained by a three-intersecting straight line model, but there still existed a significant remainder variation. The truncation of environmental range by assuming moving division points was more efficient than the fixed division points for the segmental regression models. The stability of hybrid varieties on the best fitting model has been discussed.