Bovine leukemia virus-associated antigens in lymphocyte cultures.     

D M Driscoll  C Olson 《American journal of veterinary research》1977,38(11):1897-1898

Short-term lymphocyte cultures from bovine leukemia virus (BLV)-infected cattle were tested for BLV-associated antigens at various times after incubation. Several immunologic methods were used, including fluorescent antibody tests, immunodiffusion, and radial immunodiffusion. Antigens were not detected in uncultured lymphocytes. The BLV-associated antigens were detected as early as 3 hours, with maximum antigen production occurring at 18 to 24 hours after incubation. These results indicate that culturing of lymphocytes in vitro is necessary for the expression of the virus.  相似文献   

Nutrient and heavy metals in decaying harvest residue needles on drained blanket peat forests     

Zaki-ul-Zaman Asam  Mika Nieminen  Annu Kaila  Raija Laiho  Sakari Sarkkola  Mark O’Connor  Connie O’Driscoll  Afshan Sana  Michael Rodgers  Xinmin Zhan  Liwen Xiao 《European Journal of Forest Research》2014,133(6):969-982

Harvest residue decomposition can significantly contribute to nutrient and heavy metal exports to receiving water courses. This study monitors the nutrient and heavy metal dynamics in decaying Sitka spruce and lodgepole pine harvest residue needles on Atlantic blanket peat forests in the west of Ireland. Using the litterbag method, harvest residue was placed both within and between furrows in two uncut forest and two clear-cut sites. On the clear-cut sites, the litterbags were positioned outside the harvest residue piles (i.e. brash windrows). Over the 2-year monitoring period, the needles decomposed slower at the clear-cut sites than the uncut forest sites, with mass losses of 46–55 and 58–77 %, respectively. Approximately 20 % less phosphorous (P) was released from the decaying needles at the clear-cut sites, while nitrogen (N) was released only at the uncut sites. Tree species was a significant factor contributing to nutrient and heavy metal release and accumulation patterns, with higher concentrations of aluminium (Al), nickel (Ni), cadmium (Cd) and zinc (Zn) in the decaying spruce needles than in pine. Conversely, the spruce needles showed accelerated depletion of calcium (Ca) and magnesium (Mg) relative to the pine. The harvest residue needle positioning (inside furrow/between furrows) and the site soil characteristics contributed significantly to Al transformations in spruce needles and iron (Fe) in both spruce and pine needles, with more accumulation occurring inside the furrows where Al and Fe contents of the peat were high. Manganese (Mn) was released from the needles in three of the four sites with a total release of over 90 % within 2 years. In the remaining site, where the Mn content of the peat was high, an accumulation of Mn in the needles was observed. The decomposition of needles on blanket peat catchments may be a significant source of P to receiving water courses, owing to their fast release of P, but not a likely source for N export.  相似文献   

Assessment of the Extent to Which Intensively-studied Lakes are Representative of the Adirondack Region and Response to Future Changes in Acidic Deposition     

T. J. Sullivan  B. J. Cosby  A. T. Herlihy  C. T. Driscoll  I. J. Fernandez  T. C. McDonnell  C. W. Boylen  S. A. Nierzwicki-Bauer  K. U. Snyder 《Water, air, and soil pollution》2007,185(1-4):279-291

Many lakes in the Adirondack Mountains, New York, have acidified over the past century due to acidic atmospheric deposition. More recently, most monitored lakes have shown signs of chemical recovery (increase in acid neutralizing capacity) as sulfur deposition levels have declined in response to the Clean Air Act and other emissions control legislation. We used measured and modeled trends in past lakewater acidification and projections of future recovery from acidification to extrapolate results from judgment samples of intensively studied lakes to the population of acid-sensitive Adirondack lakes. Simulations were developed for 70 watersheds using the Model of Acidification of Groundwater in Catchments (MAGIC) to classify lakes according to their sensitivity to change in atmospheric S and N deposition. MAGIC simulations suggested that the modeled Adirondack Long-Term Monitoring Project (ALTM) and Adirondack Effects Assessment Project (AEAP) lakes were largely among the lakes in the population that had acidified most between 1850 and 1990. Most of the modeled ALTM/AEAP lakes were within the top 36% of acid sensitivity, based on model projections of past acidification and future chemical recovery, compared with the 1,829 Adirondack lakes in EPA’s Environmental Monitoring and Assessment Program (EMAP) statistical frame. Results of this research will allow fuller utilization of data from on-going chemical and biological monitoring and process-level studies by providing a basis for regionalization of findings and developing/refining relationships among watershed characteristics, chemical change, and biological responses to changing levels of acidic deposition.  相似文献   

Identifying sources of snowmelt acidification with a watershed mixing model     

Douglas A. Schaefer  Charles T. Driscoll 《Water, air, and soil pollution》1993,67(3-4):345-365

We used ionic tracers to estimate the volume of old (soil and ground) water interacting with snowmelt in eleven Adirondack, NY watersheds. The contribution of old water varied from 66 to 90%, with no general relationship between old water % and soil depth to till. This approach also discriminated between watershed retention and release of particular ions to lake outlet water during snowmelt. Most watersheds released NO₃ ^? during snowmelt, in addition to the snowpack NO₃ ^?. Nitrification of snowpack NH₄ ⁺ explained part of the additional NO₃ ^? in lake out outlet water, but some NO₃ ^? was likely mineralized nitrogen from soil organic matter. All watersheds retained NH₄ ⁺ as well. Nitrogen release was greatest in the acidic watersheds in the southwestern Adirondacks, a region thought to be impacted by anthropogenic deposition. During snowmelt, Ca²⁺ and Mg²⁺ ions (presumably from soil exchange sites) were also released from most watersheds. In watersheds with acidic (minimum pH<4.6) lake outlet water, Al was also released during snowmelt. Thus, lake outlet water acidification during snowmelt was both buffered by cation release, and intensified by NO₃ ^? release. If the soil exchangeable cation pools were not replenished prior to snowmelt, or NO₃ ^? mobilization were increased, acidification during snowmelt would intensify.  相似文献   

Input-Output Budgets of Inorganic Nitrogen for 24 Forest Watersheds in the Northeastern United States: A Review     

Campbell  John L.  Hornbeck  James W.  Mitchell  Myron J.  Adams  Mary Beth  Castro  Mark S.  Driscoll  Charles T.  Kahl  Jeffrey S.  Kochenderfer  James N.  Likens  Gene E.  Lynch  James A.  Murdoch  Peter S.  Nelson  Sarah J.  Shanley  James B. 《Water, air, and soil pollution》2004,151(1-4):373-396

Input-output budgets for dissolved inorganic nitrogen (DIN) are summarized for 24 small watersheds at 15 locations in the northeasternUnited States. The study watersheds are completely forested, free of recent physical disturbances, and span a geographical region bounded by West Virginia on the south and west, and Maine on the north and east. Total N budgets are not presented; however, fluxes of inorganic N in precipitation and streamwater dominate inputs and outputs of N at these watersheds. The range in inputs of DIN in wet-only precipitation from nearby National Atmospheric Deposition Program (NADP) sites was 2.7 to 8.1 kg N ha^-1 yr^-1 (mean = 6.4 kg N ha^-1 yr^-1; median = 7.0 kg N ha^-1 yr^-1). Outputs of DIN in streamwater ranged from 0.1 to 5.7 kg N ha^-1 yr^-1 (mean = 2.0 kg N ha^-1 yr^-1; median = 1.7 kg N ha^-1 yr^-1). Precipitation inputs of DIN exceeded outputs in streamwater at all watersheds, with net retention of DIN ranging from 1.2 to 7.3 kg N ha^-1 yr^-1 (mean = 4.4 kg N ha^-1 yr^-1; median = 4.6 kg N ha^-1 yr^-1). Outputs of DIN in streamwater were predominantly NO₃-N (mean = 89%; median = 94%). Wet deposition of DIN was not significantly related to DIN outputs in streamwater for these watersheds. Watershed characteristics such as hydrology, vegetation type, and land-use history affect DIN losses and may mask any relationship between inputs and outputs. Consequently, these factors need to be included in the development of indices and simulation models for predicting 'nitrogen saturation' and other ecological processes.  相似文献   

Strain of mycoplasma associated with human reproductive failure   总被引：9，自引：0，他引：9  

R B Kundsin  S G Driscoll  P L Ming 《Science (New York, N.Y.)》1967,157(796):1573-1574

A strain of mycoplasma not previously described has been isolated from the chorion, decidua, and amnion of a patient who sustained a spontaneous abortion during the middle trimester. The fetal membranes exhibited an inflammatory reaction, but no evidence of other infectious agents, bacterial or viral, was noted. The T strain identified is not a classical mycoplasma; it differs in growth and nutritional requirements from the T strains previously characterized.  相似文献   

Yeast Rtt109 promotes genome stability by acetylating histone H3 on lysine 56   总被引：1，自引：0，他引：1  

Driscoll R  Hudson A  Jackson SP 《Science (New York, N.Y.)》2007,315(5812):649-652

Posttranslational modifications of the histone octamer play important roles in regulating responses to DNA damage. Here, we reveal that Saccharomyces cerevisiae Rtt109p promotes genome stability and resistance to DNA-damaging agents, and that it does this by functionally cooperating with the histone chaperone Asf1p to maintain normal chromatin structure. Furthermore, we show that, as for Asf1p, Rtt109p is required for histone H3 acetylation on lysine 56 (K56) in vivo. Moreover, we show that Rtt109p directly catalyzes this modification in vitro in a manner that is stimulated by Asf1p. These data establish Rtt109p as a member of a new class of histone acetyltransferases and show that its actions are critical for cell survival in the presence of DNA damage during S phase.  相似文献   

Hydrodynamic stability without eigenvalues     

Trefethen LN  Trefethen AE  Reddy SC  Driscoll TA 《Science (New York, N.Y.)》1993,261(5121):578-584

Fluid flows that are smooth at low speeds become unstable and then turbulent at higher speeds. This phenomenon has traditionally been investigated by linearizing the equations of flow and testing for unstable eigenvalues of the linearized problem, but the results of such investigations agree poorly in many cases with experiments. Nevertheless, linear effects play a central role in hydrodynamic instability. A reconciliation of these findings with the traditional analysis is presented based on the "pseudospectra" of the linearized problem, which imply that small perturbations to the smooth flow may be amplified by factors on the order of 10(5) by a linear mechanism even though all the eigenmodes decay monotonically. The methods suggested here apply also to other problems in the mathematical sciences that involve nonorthogonal eigenfunctions.  相似文献   

How many common reptile species are fire specialists? A replicated natural experiment highlights the predictive weakness of a fire succession model     

Don A Driscoll  Meredith K Henderson 《Biological conservation》2008,141(2):460-471

Species with strong preferences for early or late successional stages after fire may be extinction prone under current fire regimes. However, the extent of specialisation to time since fire is poorly understood, and, for reptiles, succession models for predicting responses are in the development phase. In this study we tested predictions of a reptile succession model, and identified species that may be fire specialists. Reptiles were sampled in five burnt and unburnt mallee Eucalyptus woodlands, Australia. Two, 400 m transects within each burn treatment were sampled using 11 pairs of pitfall-traps that were opened for five weeks over two summers. A habitat accommodation model of succession that was previously developed for mallee reptiles correctly predicted the observed responses of three of 16 common reptile species. A further four species showed non-significant trends in the predicted direction. However, eight other species showed unexpected responses. One species showed a strong interaction between burn age and location, requiring a two-dimensional successional model in contrast with the usual linear models explaining reptile responses to fire. One third of common species were not affected by fire and so may not have increased risks of extinction due to the fire suppression/incineration cycle. However, approximately half to two-thirds of common reptiles did have a fire response, so the risk of deterministic extinction in small fragments may be substantial. Further model development is needed to better predict fire responses and to assist the design of fire mosaics that can accommodate early and late successional fire specialists.  相似文献   

Animal movement varies with resource availability,landscape configuration and body size: a conceptual model and empirical example     

Doherty  Tim S.  Fist  Charles N.  Driscoll  Don A. 《Landscape Ecology》2019,34(3):603-614

Landscape Ecology - Animals must move to find food, shelter and mates, and escape predation and competition. Changes in landscape configuration and resource availability can disrupt natural...  相似文献