The role of reforestation in carbon sequestration

New Forests - In the United States (U.S.), the maintenance of forest cover is a legal mandate for federally managed forest lands. More broadly, reforestation following harvesting, recent or...     

N-acetylglutamate and N-acetylaspartate in soybeans (Glycine max L.), maize (Zea mays L.), [corrected] and other foodstuffs

N-Acetylglutamate (NAG) and N-acetylaspartate (NAA) are amino acid derivatives with reported activities in a number of biological processes. However, there is no published information on the presence of either substance in foodstuffs. We developed a method for extracting and quantifying NAG and NAA from soybean seeds and maize grain using ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS). The lower limit of quantification for both NAG and NAA was 1 ng/mL. The method was then utilized to quantify NAG and NAA in other foodstuffs (fruits, vegetables, meats, grains, milk, coffee, tea, cocoa, and others). Both NAG and NAA were present in all of the materials analyzed. The highest concentration of NAG was found in cocoa powder. The highest concentration of NAA was found in roasted coffee beans. Both NAG and NAA were found at quantifiable concentrations in all foods tested indicating that these two acetylated amino acids are common components of the human diet.     

Migration pathways,speed and mortality of Atlantic salmon (Salmo salar) smolts in a Scottish river and the near‐shore coastal marine environment

Long‐distance migration of Atlantic salmon (Salmo salar) is known to result in high levels of mortality. For a species experiencing global population decline, it is thus vital to better understand migration behaviour, both in the river and marine stages. Atlantic salmon smolts (n = 50) were tracked using acoustic telemetry in the River Deveron, Scotland, and adjacent coastal area. Higher rates of mortality were observed in the river (0.77% per km) than the early marine stage of migration (0.0% per km). Mortality likely resulted from predation. Higher swim speeds were recorded in the early marine stage compared with the river (marine = 7.37 ± 28.20 km/day; river = 5.03 ± 1.73 km/day [mean ± SD]), a potential predator avoidance behaviour. The majority of smolts leaving the river did so in darkness and on a flooding tide. Overall river and marine migration success were linked to nights of lower lunar brightness. Marine migration speed decreased with increasing environmental noise levels, a finding with implications for fisheries management. The migration pathway in the early marine environment did not follow obvious geographical features, such as the coastline. Thus, we suggest that early marine environment pathways are more influenced by complex water currents. These findings highlight factors that influence smolt migration survival and behaviour, areas on which future research should focus.     

The loss of large wood affects rocky mountain trout populations

Western U.S. rivers are currently influenced by legacy effects of reduced large wood (LW) loading and retention that has substantially reduced in‐stream habitat complexity. Large wood is typically associated with streams in undisturbed old‐growth forest and in the correct geomorphic context can drastically alter stream and valley habitat complexity. Streams with LW are typically multichannel and depositional, while streams lacking LW, due to relatively recent wildfire or logging (<200 years ago), are usually single channelled and erosional. We compared population biomass and individual growth rates of Brook Trout Salvelinus fontinalis in streams across a gradient of wood volumes. At both the square metre and valley length scales, standing stock biomass of aquatic invertebrates was the best predictor of trout biomass. However, at the valley scale, the number of pools was important in predicting trout biomass in combination with standing stock biomass of aquatic invertebrates. Individual growth rates of age‐1 Brook Trout were negatively affected by increasing density; however, growth rates for the largest and smallest individuals at each site were unaffected by density. Our results suggest the pool habitat created by LW acts synergistically with prey availability to dramatically increase trout populations. However, in streams lacking LW, negative effects of detrimental land use practices have persisted >100 years, suggesting that recovering lost animal production in mountain stream networks will only occur at decadal to century time scales.     

Influence of climate and abundance on migration timing of adult Atlantic salmon (Salmo salar) among rivers in Newfoundland and Labrador

Evidence mounts for the influence of climate variability on temporal trends in the phenology of many organisms including various species of fish. Accordingly, we examined variation in adult Atlantic salmon Salmo salar run timing in thirteen Newfoundland and Labrador rivers where returns were monitored at fishways or fish‐counting fences. Run timing varied significantly among rivers with the median date of return differing by up to 5 weeks. Duration of runs was generally short with most adults returning over a period of three to 5 weeks. A mixed model analysis incorporating a first‐order autoregressive error structure was used to generalise changes in run timing among all monitored rivers. Results indicated that the median date of return has advanced by almost 12 days over a 35‐year interval from 1978 to 2012, while several individual rivers have advanced by almost 21 days. The influence of climate on median timing was evident when the simultaneous effects of both climate and salmon abundance were controlled. We found earlier runs associated with overall warmer climate conditions on the Newfoundland and Labrador Shelf. Results contrast with those from the north‐east Atlantic where Atlantic salmon are returning later in some rivers coincident with warming climate conditions.     

Comparison of temperature readings from a percutaneous thermal sensing microchip with temperature readings from a digital rectal thermometer in equids

OBJECTIVE: To compare temperature readings from an implantable percutaneous thermal sensing microchip with temperature readings from a digital rectal thermometer, to identify factors that affect microchip readings, and to estimate the sensitivity and specificity of the microchip for fever detection. DESIGN: Prospective study. ANIMALS: 52 Welsh pony foals that were 6 to 10 months old and 30 Quarter Horses that were 2 years old. PROCEDURES: Data were collected in summer, winter, and fall in groups 1 (n = 23 ponies), 2 (29 ponies), and 3 (30 Quarter Horses), respectively. Temperature readings from a digital rectal thermometer and a percutaneous thermal sensing microchip as well as ambient temperature were recorded daily for 17, 23, and 19 days in groups 1 through 3, respectively. Effects of ambient temperature and rectal temperature on thermal sensor readings were estimated. Sensitivity and specificity of the thermal sensor for detection of fever (rectal temperature, >or= 38.9 degrees C [102 degrees F]) were estimated separately for data collection at ambient temperatures 15.6 degrees C. RESULTS: Mean ambient temperatures were 29.0 degrees C (84.2 degrees F), -2.7 degrees C (27.1 degrees F), and 10.4 degrees C (50.8 degrees F) for groups 1 through 3, respectively. Thermal sensor readings varied with ambient temperature and rectal temperature. Rectal temperatures ranged from 36.2 degrees to 41.7 degrees C (97.2 degrees to 107 degrees F), whereas thermal sensor temperature readings ranged from 23.9 degrees (75 degrees F) to 42.2 degrees C (75 degrees to 108 degrees F). Sensitivity for fever detection was 87.4%, 53.3%, and 58.3% in groups 1 to 3, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: The thermal sensor appeared to have potential use for initial screening of body temperature in equids at ambient temperatures > 15.6 degrees C.     

Transverse ulnar bone transport osteogenesis: a new technique for limb salvage for the treatment of distal radial osteosarcoma in dogs

Objective— To develop instrumentation and a technique for transverse ulnar bone transport osteogenesis in dogs.
Study Design— Cadaveric study and in vivo validation (1 dog).
Sample Population— Paired cadaveric antebrachii (n=10 dogs) and 1 live dog.
Methods— Circular fixator constructs were applied and fitted with reeling or linear motors designed to transport an ulnar segment transversely into a defect created by excising the distal 50% of the ipsilateral radius. A longitudinal osteotomy of the adjacent ulna was created and the segment was transported across the radial defect. Pre- and post-distraction CT scans were used to compare the efficacy of each construct. The procedure was performed unilaterally in a live dog using the reeling motor (RM) construct.
Results— Both constructs effectively transported the ulnar segment into the defect. Subjectively, the RMs were easier to apply and operate. No significant differences were observed in the objective measures of efficacy between the 2 construct types. The live dog produced viable regenerate bone after transverse ulnar bone transport.
Conclusions— Transverse ulnar bone transport should be considered a potential method for limb salvage in dogs with osteosarcoma (OSA) of the distal radius. The RMs were effective and clinically applicable.
Clinical Relevance— Transverse ulnar bone transport osteogenesis affords the benefits of longitudinal radial bone transport osteogenesis, allowing resolution of large longitudinal radial defects in a substantially less time as a result of shortening the transport distance. This would be beneficial when treating conditions such as OSA where minimizing convalescence and maximizing quality of life is a priority.     

AGE AND DIET EFFECTS ON RELATIVE RENAL ECHOGENICITY IN GERIATRIC BITCHES

Under controlled, but varied dietary conditions 35 geriatric, uninephrectomized, spayed Beagle bitches (dogs) observed for 4 years, renal cortical and renal medullary echogenicity was measured relative to hepatic and splenic echogenicity. Regardless of the diet fed, 60-75% of these aged dogs had renal cortical echogenicity less than that of either the liver or spleen across time; 25-35% of these dogs had renal cortical echogenicity equal to that of the liver, but less than that of the spleen across time. Less than 3% of these dogs had renal cortical echogenicity greater than that of the liver, but less than that of the spleen. Only 1 (one) of these dogs had renal cortical echogenicity equal to that of the spleen and that occurred at only one of the 14 chronologic assessments. Therefore, in either mature or aged dogs imaged with 4.0 to 5.0 MHz equipment, the renal cortical echogenicity should be considered normal if it is less than or equal to that of the liver and less than that of the spleen. In 29 dogs imaged with the 4.0/5.0 MHz equipment and 6 dogs imaged with 7.5 MHz equipment, there was no significant diet or individual dog effect. The 7.5 MHz (6 dog) group had significantly higher average cortical echogenicity scores than the 4.0/5.0 MHz (29 dog) group. However, the occurrence of renal cortical echogenicity greater than liver echogenicity was seen in only 5 of 83 samples (approximately 6.0%) made on 6 dogs imaged with 7.5 MHz equipment and only 1 of 375 samples (approximately 0.27%) made on 29 dogs with 4.0/5.0 MHz equipment. With the exception of one occurrence, all dogs had renal medullary echogenicity less than that of the liver or spleen regardless of imaging equipment frequency. The renal medulla was always hypoechoic compared to the cortex.