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Focuses on estimating the energetic cost of bird flight through the wind-tunnel method. Problems in several methods such as aerodynamic calculations and studies of the rate of oxygen consumption; Purpose of the plastic mask worn by the bird in the wind-tunnel method; Ways to determine oxygen consumption and carbon dioxide production of birds in flight.

The use of ultra-sensitive low copy number (LCN) DNA typing allows the analysis of picogram amounts of DNA. Trace evidence accidentally left at a scene of crime (SOC) by the investigating team may be inadvertently collected and analysed, potentially leading to spurious evidence being introduced into the criminal investigation. A series of experiments were undertaken to determine the extent to which an investigator could contribute to any DNA contamination of a scene of crime under different simulated activities. Further, the degree to which any contamination was reduced by the use of commercially available protective clothing was demonstrated. Precautions that should routinely be taken at a scene of crime to reduce the risk of DNA contamination are recommended.

In order to follow the course of bone marrow engraftment in dogs, and to determine the presence, and percentage, of donor-derived cells in other canine tissues, a simple and fast method of determining cell origin after sex-mismatched bone marrow transplantation was developed.

Albert, T. S. E., V. L. Tucker, and E. M. Renkin. Acute alveolar hypoxia increases blood-to-tissue albumin transport: role of atrial natriuretic peptide. J. Appl. Physiol.82(1): 111–117, 1997.—Plasma immunoreactive atrial natriuretic peptide (irANP) and blood-to-tissue clearance of 131I-labeled rat serum albumin (CRSA) were examined in anesthetized rats during hypoxic ventilation (n= 5–7/group). Hypoxia (10 min) increased irANP from 211 ± 29 (room air) to 229 ± 28 (15% O2, not significant), 911 ± 205 (10% O2), and 4,374 ± 961 pg/ml (8% O2), respectively. Graded increases in CRSAwere significant at 8% O2in fat (3.6-fold), ileum (2.2-fold), abdominal muscles (2.0-fold), kidney (1.8-fold), and jejunum (1.4-fold). CRSAwas decreased in back skin and testes; heart, brain, and lungs were unaffected. The increases in CRSAwere related to irANP and not to arterialPO2. Circulating plasma volume was negatively correlated with whole body CRSA. Graded increases in extravascular water content (EVW) were found in the kidney, left heart, and cerebrum and were positively related to CRSAin the kidney. EVW decreased in gastrointestinal tissues; the magnitude was inversely related to CRSA. We conclude that ANP-induced protein extravasation contributes to plasma volume contraction during acute hypoxia.

Albert, T. S. E., V. L. Tucker, and E. M. Renkin.Atrial natriuretic peptide levels and plasma volume contraction in acute alveolar hypoxia. J. Appl. Physiol.82(1): 102–110, 1997.—Arterial oxygen tensions (PaO2), atrial natriuretic peptide (ANP) concentrations, and circulating plasma volumes (PV) were measured in anesthetized rats ventilated with room air or 15, 10, or 8% O2(n= 5–7). After 10 min of ventilation, PaO2values were 80 ± 3, 46 ± 1, 32 ± 1, and 35 ± 1 Torr and plasma immunoreactive ANP (irANP) levels were 211 ± 29, 229 ± 28, 911 ± 205, and 4,374 ± 961 pg/ml, respectively. AtPaO2≤40 Torr, irANP responses were more closely related to inspired O2(P= 0.014) than toPaO2(P= 0.168). PV was 36.3 ± 0.5 μl/g in controls but 8.5 and 9.9% lower (P≤ 0.05) for 10 and 8% O2, respectively. Proportional increases in hematocrit were observed in animals with reduced PV; however, plasma protein concentrations were not different from control. Between 10 and 50 min of hypoxia, small increases (+40%) in irANP occurred in 15% O2; however, there was no further change in PV, hematocrit, plasma protein, or irANP levels in the lower O2groups. Urine output tended to fall during hypoxia but was not significantly different among groups. These findings are compatible with a role for ANP in mediating PV contraction during acute alveolar hypoxia.