Phosphate release from synthetic glasses and inhibition of phosphate fixation on ferric hydroxide

Release of phosphate from glasses in the systems basalt-K₃PO₄ granite-K₂SiO₃ Na₂SiO₃-apatite has been studied. Equilibrium leachate concentrations in water are attained in 3-5 hr (K⁺, 5-60 μg cm^-3; PO₄ ³-, 2-15 μg cm^-3). Glass composition, pH, and grain size influence solubility.

Phosphate fixation on freshly precipitated Fe(OH)₃ and on iron-rich laterites appear to be inhibited when glasses are rich in Na-K silicates. This may be due to surface modification of Fe(OH)₃ by the formation of sodium ferric silicates which are known to be stable at low temperatures.     

Standing in the canine precision medicine knowledge gap: Improving annotation of canine cancer genomic biomarkers through systematic comparative analysis of human cancer mutations in COSMIC

The accrual of cancer mutation data and related functional and clinical associations have revolutionised human oncology, enabling the advancement of precision medicine and biomarker-guided clinical management. The catalogue of cancer mutations is also growing in canine cancers. However, without direct high-powered functional data in dogs, it remains challenging to interpret and utilise them in research and clinical settings. It is well-recognised that canine and human cancers share genetic, molecular and phenotypic similarities. Therefore, leveraging the massive wealth of human mutation data may help advance canine oncology. Here, we present a structured analysis of sequence conservation and conversion of human mutations to the canine genome through a ‘caninisation’ process. We applied this analysis to COSMIC, the Catalogue of Somatic Mutations in Cancer, the most prominent human cancer mutation database. For the project's initial phase, we focused on the subset of the COSMIC data corresponding to Cancer Gene Census (CGC) genes. A total of 670 canine orthologs were found for 721 CGC genes. In these genes, 365 K unique mutations across 160 tumour types were converted successfully to canine coordinates. We identified shared putative cancer-driving mutations, including pathogenic and hotspot mutations and mutations bearing similar biomarker associations with diagnostic, prognostic and therapeutic utility. Thus, this structured caninisation of human cancer mutations facilitates the interpretation and annotation of canine mutations and helps bridge the knowledge gap to enable canine precision medicine.     

Mechanical cleaning and prescribed burning for recruiting commercial tree regeneration in a Bolivian dry forest

A critical component of sustainable forest management is the regeneration of commercially valuable tree species. Mechanical cleaning with machetes and chainsaws, prescribed burning, and a combination of both treatments were applied to recently-created logging gaps in a Bolivian dry forest to evaluate their impact on the natural regeneration of commercial tree species and on control of competing vegetation. The three treatments and an untreated control were applied to logging gaps during the dry season of 1998 and replicated ten times. Eight months following burning, the density of commercial tree regeneration in gaps did not differ statistically among treatments. Relative height growth of total commercial regeneration also did not differ among treatments, although it did vary by species. Reduction in competing vegetation following the application of site preparation treatments was significantly higher, but competing plant cover was beginning to converge among treatments after eight months. Despite better control of competing vegetation, early recruitment and growth responses to burning and cleaning of vegetation in logging gaps do not appear to justify application of these treatments in this forest, especially considering their high costs.     

Soil compaction effects on water status of ponderosa pine assessed through 13C/12C composition

Soil compaction is a side effect of forest reestablishment practices resulting from use of heavy equipment and site preparation. Soil compaction often alters soil properties resulting in changes in plant-available water. The use of pressure chamber methods to assess plant water stress has two drawbacks: (1) the measurements are not integrative; and (2) the method is difficult to apply extensively to establish seasonal soil water status. We evaluated leaf carbon isotopic composition (delta13C) as a means of assessing effects of soil compaction on water status and growth of young ponderosa pine (Pinus ponderosa var. ponderosa Dougl. ex Laws) stands across a range of soil textures. Leaf delta13C in cellulose and whole foliar tissue were highly correlated. Leaf delta13C in both whole tissue and cellulose (holocellulose) was up to 1.0 per thousand lower in trees growing in non-compacted (NC) loam or clay soils than in compacted (SC) loam or clay soils. Soil compaction had the opposite effect on leaf delta13C in trees growing on sandy loam soil, indicating that compaction increased water availability in this soil type. Tree growth response to compaction also varied with soil texture, with no effect, a negative effect and a positive effect as a result of compaction of loam, clay and sandy loam soils, respectively. There was a significant correlation between 13C signature and tree growth along the range of soil textures. Leaf delta13C trends were correlated with midday stem water potentials. We conclude that leaf delta13C can be used to measure retrospective water status and to assess the impact of site preparation on tree growth. The advantage of the leaf delta13C approach is that it provides an integrative assessment of past water status in different aged leaves.     

Overwintering ofTrichogramma evanescens Westw. in Egypt (Trichogrammatidae,Hymen.)

Eggs ofA. kuehniella parasitized byT. evanescens were held outdoors in a shadow place during the period from November 20th, up to parasite emergence. Blackness of the parasitized eggs appeared 3 days later.Overwintering lasted for 99 days starting from 24th, November till 2nd of March at an average temperature of 10.1° C. When temperature increased to an average of 16.6° C, the parasitoids continued their development for 5 days till the emergence of adults.Emerged adult parasitoids showed relatively normal bioaspects as those reared in the laboratory.With 2 tables     

Effect of mating on egg production in two species of predatory mites,Agistemus exsertus Gonzalez andPhytoseiulus persimilis Athias — Henriot

The influences of single and multiple matings on egg production in the two predacious mitesAgistemus exsertus Gonz. andPhytoseiulus persimilis Ath. — Hen. were investigated in the laboratory. with both species egg production was increased as a result of multiple matings, but this increase was insignificant. In addition, mated females ofA. exsertus commenced oviposition one day earlier compared to unmated ovipositing females.With 1 table     

Modeling changes in habitat conditions in northern hardwoods forests of the Adirondack Mountains of New York

Interest in enhancing the management of forest timber and wildlife resources has stimulated the development of modeling techniques to predict changes in timber and wildlife habitat characteristics. We assess the potential of combining models which predict forest structure with those which assess habitat quality to predict changes in forest habitat characteristics. We measured variables important to simulating forest growth and evaluating wildlife habitat in even-aged stands making up an 80 year chronosequence, and developed mathematical relationships between these sets of variables. The regression relationships were generally excellent (r² or R² > 0.63), and most habitat variables were strongly related to stand age. In earlier work, we incorporated these models into FORET, a model that successfully simulates succession in hardwoods forests of the eastern USA. In the present study, we adapted FORET to accommodate the growing season and species composition of northern hardwoods forests of the Adirondack Mountains of New York, creating a new model called FORDACK. We compared stand measurements with output generated by the model. FORDACK accurately simulated changes in structural characteristics of vegetation and predicted which species would be present in very low densities, but did not successfully predict the relative densities of the dominant species. Predictions were closest to actual conditions from 20 to 50 years after regeneration. The model performed well in predicting trends in habitat variables such as canopy height and closure. Departures of simulated conditions from the actual were greatest early (less than 20 years) and late in stand development (more than 50 years). Poor performance in predicting species composition may be related to excluding management history and site characteristics from the model. The approach exemplified by FORDACK shows good potential for predicting structural characteristics of wildlife habitat.     

Effect of burning and brush treatments on nutrient and soil physical properties in young longleaf pine stands

Over a period of 16 years, unburned longleaf pine (Pinus palustris Mill.) pole stands grew an average of 27% more volume than similar stands regularly burned. Treatments included biennial burns in winter, spring, and summer plus an unburned check, each of which was combined with three supplemental treatments, namely, initial herbicide injection of all hardwoods, repeated handclearing of all woody stems, and no treatment. All unburned and winter-burned plots were paired to study this growth reduction relative to treatments. The status of nitrogen, phosphorus, available moisture holding capacity, bulk density, and macropore space was determined in both surface and subsurface soils. Foliage from pines on sampled plots was analyzed for N, P, K, Ca, Mg, Mn, Cu, Fe, and Zn. Burning did not significantly affect either soil N and P or foliar nutrients. However, burning reduced available moisture holding capacity and macropore space and increased the bulk density of surface soils, and also reduced the moisture-holding capacity of subsurface soils. The results from this and other studies suggest that growth losses are due, at least in part, to increased moisture stress associated with changes in soil physical properties.     

Development of 8-armed airflow olfactometers for measuring olfactory responses of insect predators

In the present study two types of 8-armed airflow olfactometers are developed, one is for individual test, called the individual olfactometer, another is for population test, called the population olfactometer. Both of them consist of an exposure chamber, 8 odour arms, 8 odour chambers and a sample plate or a sample chamber. In the former, the odour chamber is movable for regulating the distance between an odour source and the exposure chamber. In the latter, the sample chamber can be driven up and down to control the predator population under test to be exposed to the exposure chamber at the same time, and the odour chambers are designed for two functions viz., for placing odour sources and for catching the predator reaching them. By means of the NH₄CL smoke tests, it is clear that the odour airflows in both apparatus are separated in the outward area of the exposure chamber and gradually unified around the center to form the combination of the odour fields, from which the predator under test begins searching the odours. The control tests for random distribution in both apparatus have been conducted to provide the evidence that the same odour source in all odour chambers causes the random selection by the predator. The one-odour tests have been executed to prove the sensitivity of both apparatus for testing insect kairomone responses.