Auxin-Regulated Reversible Inhibition of TMK1 Signaling by MAKR2 Modulates the Dynamics of Root Gravitropism

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A Disynaptic Circuit in the Globus Pallidus Controls Locomotion Inhibition

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Stirtonia, a new genus of the tribe Podalyrieae (Leguminosae) from South Africa

The genus Stirtonia is described to accommodate three anomalous species, hitherto placed in Podalyria . The new genus differs from Podalyria mainly in the decussate (geminate) inflorescence structure (racemose in Podalyria ), the yellow flower colour (purple, pink or white in Podalyria ), the non-fleshy rim-aril of the seeds (seed aril invariably fleshy and collar-like in Podalyria ) and in the diagnostically different combination of quinolizidine alkaloids. The major alkaloidal metabolites are carboxylic acid esters of lupanine and virgiline, but these compounds are totally absent in Podalyria . The morphology of inflorescences, leaves, flowers and seeds are described and illustrated. Chromosome numbers (2n = 18) are reported for the first time. A formal taxonomic treatment of the three species, S. tayloriana, S. chrysantha and S. insignis , is presented.     

Habitat loss and anthropogenic disturbance in Jamaica's Hellshire Hills area

This study provides empirical assessments of the magnitude of human pressures on forest habitat in Jamaica's Hellshire Hills. The Hellshire Hills represents an outstanding example of the Caribbean region's dry limestone forests. Approximately 160 km² in area, the Hellshire Hills is home to a unique and rich biodiversity, including the critically endangered Jamaican Iguana (Cylcura collei). The area's biodiversity is under increasing threat from deforestation from subsistence driven encroachment. Using deforestation as a spatial indicator of habitat loss, the study derives satellite based estimates of the rate of habitat destruction within and immediately outside the area. The underlying human driving forces in this destruction are analyzed in a regression analysis of key socio-economic indicators that adusts for these locational differences. Results suggest that immiserating pressures on species habitat, particularly outside the area, are greater than anywhere else on the island. Simulations of species loss and edge-induced disturbances to species habitat also indicate that the potential impacts of forest conversion may be substantial and extend well beyond the area's boundaries. Together, the study's results highlight the intrinsic vulnerablity of the Hellshire Hills to outside disturbance. In particular, they raise doubts about the potential of the area (which has been accorded protected status within the recently established Portland Bight Protected Area) to provide for the long-term preservation and viability of the area's species. It is concluded that appropriate reserve design and species protection will require the collection of detailed empirical data on species diversity, numbers, habitat requirements, and spatial distribution. However, before this information can be collected priorities for biodiversity conservation must be set. Costs and benefits of conversation must also be assessed within the overall context of an integrated rural development plan for the area.     

Production of food yeasts from the solid fraction of palm oil

Summary Growth parameters of different species of yeast on ammonium soaps have been determined. All tested strains are able to use the solid part of palm oil, transformed into ammonium soaps. Growth parameters are acceptable for industrial use and it is possible to produce single cell protein from this substrate.     

Immunologic findings in healthy Haitians in Montreal

To investigate the occurrence of acquired immune deficiency syndrome in Haitians, a health status questionnaire was administered and selected studies of immune status done in a randomly chosen sample of 189 healthy adult Haitians living in Montreal. The study group was comparable to a large sample of Haitians in Montreal interviewed in the 1981 census with respect to age, sex, number of persons per household and year of immigration, but the proportion of currently married people in the study was larger (60.8% v. 42.6%). The results in the study group were compared with those in a sample of 189 non-Haitians matched for age, sex and neighbourhood of residence. Persons with known causes of impaired immune function were excluded. The participation rate was 87.5%. The study and control groups both reported few symptoms and chronic health problems and had comparable demographic data, including rate of employment and income. The mean total numbers of lymphocytes, OKT3 and OKT4 (helper) and OKT8 (suppressor) cells were significantly higher in the Haitians than in the controls, though still within normal limits. There was a borderline elevation of the lymphocyte response to phytohemagglutinin in the Haitians. The ratios of helper to suppressor T cells in the two groups were, however, not significantly different. The Haitians, in comparison with non-Haitians living in the same community, had no demonstrable abnormalities of cellular immune function.     

Laboratory method for testing side-effects of pesticides on the rove beetleAleochara bilineata — Adults

Tests were conducted in glass cells containing moistened sand sprayed with the concentration recommended for the pesticide or with demineralised water (controls). Adult females (1–2 weeks old) ofA. bilineata were placed on the fresh residue in the cells and provided daily with fresh fly eggs as food. The duration of the test was 5 days, mortality being recorded every day. The side effects of the pesticide were expressed as reduction in egg production ofA. bilineata during the whole test period. Results permitted classification of the pesticides according to the 4 categories of harmfulness used by the IOBC working group. 23 pesticides were tested, and the reproducibility of the test appeared to be satisfactory. Generally, insecticides/acaricides had a pronounced effect on the beetles whereas fungicides and herbicides were less detrimental. Exceptions were the insecticides Tedion V 18 and Kilval, classified as harmless, and the fungicides Morestan, Pomarsol forte and Afugan rated as moderately harmful. Among growth regulators Prosevor 85 was highly detrimental while Cycocel Extra and Rhodofix had no effects. Excepting Morestan, Pomarsol forte and Ustinex PA the pesticides did not affect the hatching of eggs. The work was financed by the Danish Environmental Protection Agency.