Road verges as habitat for small mammals in Britain

There are 370 000 kilometres of roads in Great Britain, mostly bordered by a verge that is potential habitat for small mammals. The present study assessed the importance of road verges as small mammal habitat and investigated the influence of some key features on rodent abundance. Five rodent and three shrew species were live‐trapped on 14 road verges in late summer 1994 and nine verges in autumn 1996 in north Cambridgeshire, UK. On average, between three and four species were captured per verge. Bank Voles Clethrionomys glareolus, Wood Mice Apodemus sylvaticus and Field Voles Microtus agrestis were the most abundant species, with mean densities of 45.5, 40.2 and 29.5 animals km^–1 in summer and 52.8, 181.9 and 47.2 animals km^–1 in autumn. Numbers varied between verges and this was significantly correlated with particular features on the verge. Bank Vole and Field Vole numbers showed a significant positive correlation with the dimensions of hedges and the width of the tall grass area, respectively. Wood Mice were also more numerous on verges with big hedges but the relationship between mouse abundance and verge structure was complex. The number of mice in 1994 was positively and significantly correlated with hedge features and with the width of the short grass sightline, whereas, in autumn 1996, they were only significantly correlated with total verge width (positive association) and ditch width (negative association).     

Physical and immunochemical properties of low-buoyant-density proteoglycans from avian cartilage

A proteoglycan link fraction (A₁D₅) from avian xyphoid cartilage contains one link protein and low-buoyant-density proteoglycans. An antiserum made against this fraction (anti-A₁D₅ serum) specifically binds [³⁵S]sulfate-labeled proteoglycans from aggregate (A₁), monomer (A₁D₁), and link (A₁D₅) fractions synthesized by 14-day embryonic chick sterna. When [³⁵S]sulfate-labeled proteoglycans from either monomer (A₁D₁) or link (A₁D₅) fractions are used as the antigen, anti-A₁D₅ serum binds as well as an antiserum against a purified monomer preparation (anti-A₁D₁1400 Vo serum). However, reduction and alkylation of the proteoglycans from the monomer fraction does reveal differences in the binding of the two antisera. Whereas reduction and alkylation of the antigen (³⁵S-A₁D₁) inhibit binding by both antisera, binding of the anti-A₁D₅ serum is more affected by antigen alteration. Differences in the two antisera can also be detected in assays using labeled aggregate as antigen. Anti-A₁D₅ serum cannot maintain the same levels of antigen binding as the anti-A₁D₁-1400 Vo serum when compared in an antibody dilution curve. In addition, anti-A₁D₁-1400 Vo serum can stabilize aggregate during sedimentation in a sucrose density gradient containing 4 m guanidine hydrochloride whereas anti-A₁D₅ serum cannot. These results suggest that the low-buoyant-density proteoglycans found in the link (A₁D₅) fraction from avian cartilage contain some of the antigenic determinants found on the proteoglycan monomer. However, there is at least one monomer determinant which is not present in the A₁D₅ fraction.     

Simultaneous choice bioassays accompanied by physiological changes identify civetone and decanoic acid as pheromone candidates for giant pandas

Chemicals present in urine are thought to play an important role in mate identification in the solitary giant panda (Ailuropoda melanoleuca). During the breeding season, females will deposit chemical signals to advertise sexual receptivity to potential mates. The goal of this study was to determine if specific volatile compounds found in female urine could be considered as pheromones that elicit behavioral and physiological responses in males. Experimental simultaneous choice trials were conducted with captive male giant pandas (n = 3) housed at Memphis Zoo, San Diego Zoo, and Zoo Atlanta. Octanoic acid, 1H-pyrrole-2-carboxaldehyde, decanoic acid, and civetone were selected as stimuli because previous studies reported their elevation in urine during the breeding season. Male interest was determined by a behavioral preference toward these volatile compounds diluted in synthetic urine compared with nontreated synthetic urine. Male urine samples were collected 1 week prior, during, and 1 week after the experimental period to assess changes in urinary semiochemical composition and urinary androgen concentrations. No significant differences in investigation response (p = .395) or flehmen response (p = .600) were found when stimuli were compared; however, decanoic acid and civetone elicited a behavioral preference over the control (response ratio > 0.5). The relative abundance of 16 compounds identified in male urine was significantly elevated (p < .05) above baseline values after the males were exposed to the stimuli. Androgen levels were significantly elevated (p < .05) in one male after exposure to 1H-pyrrole-2-carboxaldehyde, decanoic acid, and civetone. These data suggested that civetone and decanoic acid in female urine may motivate sexual responses in males.     

The vaterite cover on the eggs of Anhinga anhinga and its effect on gas conductance (Aves: Anhingidae)

The nature of the chalky cover of Anhinga eggshells and its effect on gas conductance were studied. The cover consisted of microscopic spheres of nearly pure CaCO₃ in the form of vaterite. The pore canals were unbranched with an inorganic cap (Board's type 3(a) (ii)). The cover acted as a resistance in series with the underlying calcitic shell and accounted for approximately 6% of the total conductance.     

Lipoprotein and protein binding of the calcium channel blocker diltiazem

The plasma protein binding properties of the calcium channel blocker diltiazem were studied using a three-chamber equilibrium dialysis system. Diltiazem is 81% bound to human sera with significant inter-individual variation. The relative binding of diltiazem by lipoproteins and alpha 1-acid glycoprotein was higher than by albumin. The binding to low density lipoprotein was strong and appeared not to be associated with the surface apoprotein.     

Capillary transport of adenosine

We tested the hypothesis that capillary exchange of adenosine is influenced by the ability of endothelial cells (ECs) to take up adenosine. Triple-indicator diffusion experiments were performed by injecting [14C]adenosine, [3H]9-beta-D-arabinofuranosylhypoxanthine ( [3H]araH), and radioiodinated serum albumin (RISA) into the arterial perfusate of isolated nonworking guinea pig hearts. Tracer appearance in venous effluent was observed over time. The early extraction of [14C]adenosine was much higher than that of [3H]araH. Extracted [3H]araH returned to the vascular space, but [14C]adenosine did not. Quantitative analysis of the curves by using a mathematical model indicates that approximately half of the extracted adenosine enters ECs and is metabolized. The remainder enters the interstitium and is taken up by myocytes, ECs, or other cells and is metabolized. We conclude that uptake of adenosine by ECs represents a significant influence on the capillary exchange of adenosine.