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By the year 2100, temperatures are predicted to increase by about 6 °C at higher latitudes and about 3 °C in the tropics. In spite of the smaller increase in the tropics, consequences may be more severe because the climatic niches of tropical species are generally assumed to be rather narrow due to a high degree of climate stability and higher niche specialisation. However, rigorous data to back up this notion are rare. We chose the megadiverse genus Anthurium (Araceae) for study. Considering that the regeneration niche of a species is crucial for overall niche breadth, we focused on the response of germination and early growth through a temperature range of 24 °C of 15 Anthurium species, and compared the thermal niche breadth (TNB) with the temperature conditions in their current range, modelled from occurrence records. Surprisingly, an increase of 3 °C would lead to a larger overlap of TNB of germination and modelled in situ temperature conditions, while the overlap of TNB of growth with in situ conditions under current and future conditions is statistically indistinguishable. We conclude that future temperatures tend to be closer to the thermal optima of most species. Whether this really leads to an increase in performance depends on other abiotic and biotic factors, most prominently potentially changing precipitation patterns.

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Quiescent cottonseeds (Gossypium hirsutum L.) were fractionated non-aqueously to protein bodies and nonparticulate cytoplasm for analyses of sugar contents. Nonparticulate cytoplasm was more than 3-fold richer in total free sugars than were protein bodies, but based on the content of cytoplasm in each fraction, sugars were distributed almost equally in them. Thin-layer chromatography and high-pressure liquid chromatography revealed five sugars: sucrose, raffinose, tetrasaccharides I and II, and stachyose. Raffinose and stachyose were located mainly, and tetrasaccharide I totally, in nonparticulate cytoplasm compared to protein bodies; sucrose and tetrasaccharide II were distributed about equally in each fraction.

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Several effects of peroxides on protein have been described in the literature. Some of the effects have been ascribed to alterations in protein conformation but this has never been examined directly. This paper described responses of peanut storage globulin (arachin) to rancid oil and hydrogen peroxide as measured by electrophoretic mobility, antigenicity and circular dichroism of the globulin. Rancid oil and 3% hydrogen peroxide had little effect on these properties but 30% hydrogen peroxide increased the mobility, abolished the antigenicity and reduced the ordered structural modes of the protein. The results indicated that changes in protein conformation do not occur after contact with organoleptically rancid oil or dilute peroxides but do occur with concentrated peroxides.

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Acidified 2,2-dimethoxypropane was used to chemically dehydrate biologic tissues for examination in the electron microscope. The ultrastructural integrities of single-celled algae, plant tissues (cotyledon, root, leaf) and animal tissues (liver, pancreas, muscle, cartilage) were maintained. Our technique was simpler and quicker than physically exchanging water for organic solvents (e.g., acetone, ethanol) as generally performed in microscopy.

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