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1.
  1. Birds colliding with turbine rotor blades is a well‐known negative consequence of wind‐power plants. However, there has been far less attention to the risk of birds colliding with the turbine towers, and how to mitigate this risk.
  2. Based on data from the Smøla wind‐power plant in Central Norway, it seems highly likely that willow ptarmigan (the only gallinaceous species found on the island) is prone to collide with turbine towers. By employing a BACI‐approach, we tested if painting the lower parts of turbine towers black would reduce the collision risk.
  3. Overall, there was a 48% reduction in the number of recorded ptarmigan carcasses per search at painted turbines relative to neighboring control (unpainted) ones, with significant variation both within and between years.
  4. Using contrast painting to the turbine towers resulted in significantly reduced number of ptarmigan carcasses found, emphasizing the effectiveness of such a relatively simple mitigation measure.
  相似文献   
2.
Syrticola mediterraneus n. sp. belonging to the family Cylindropsyllidae Sars (sensu Lang, 1948) is described from the Bay of Calvi (Corsica). The species is closely related to (?) Notopontia galapagoensis Mielke, 1982 and Syrticola flandricus Willems & Claeys, 1982. The former species is now transferred to the genus Syrticola as Syrticola galapagoensis n. comb.  相似文献   
3.
The role of a pertussis toxin sensitive GTP-binding protein in mediating between cholecystokinin receptors and phosphatidylinositol 4,5-bisphosphate phosphodiesterase as well as in preventing cholecystokinin from increasing cellular cyclic AMP has been investigated using dispersed acini from rabbit pancreas. Pertussis toxin pretreatment (500 ng/ml, 2 h) did not affect cholecystokinin(octapeptide) (CCK-8)-induced increases in cytosolic free Ca2+ as judged from changes in fluorescence obtained from quin2-loaded acini. Although pretreatment with pertussis toxin was also without effect on resting acinar cell cyclic AMP levels, adenylate cyclase activity was increased, since inhibition of cyclic AMP phosphodiesterase activity by isobutylmethylxanthine (IBMX) resulted in an additional increase in cyclic AMP levels in toxin-treated acini, indicating that acinar cell adenylate cyclase activity is under some tonic inhibitory control by the pertussis toxin-sensitive inhibitory GTP-binding protein (Gi) of the adenylate cyclase system. CCK-8 gave an increase in cyclic AMP levels in both control (1.6-fold) and toxin-treated (2.3-fold) acini, leading to cyclic AMP levels in the toxin-treated acini 2-times as high as those in control acini. In the presence of IBMX, the cyclic AMP response to CCK-8 was again markedly enhanced in acini pretreated with the toxin (3.2- vs. 1.8-fold), resulting in cAMP levels in the toxin-treated acini 3.7-times those in the absence of IBMX, 2.5-times those in control acini in the presence of IBMX and 7.0-times those in control acini in the absence of IBMX. Neither the pretreatment with pertussis toxin, nor the presence of IBMX alone, nor the combination had an effect on basal amylase secretion. However, all three treatments potentiated the stimulatory effect of CCK-8 on amylase secretion and the amount of potentiation was proportional to the cyclic AMP levels reached. Our findings suggest that in the intact pancreatic acinar cell Gi inhibition of the catalytic subunit of the adenylate cyclase may largely be responsible for preventing cholecystokinin from increasing cellular cyclic AMP. They moreover show that cyclic AMP is a modulatory agent in rabbit pancreatic enzyme secretion, not able to stimulate secretion itself, but potentiating effects mediated by the phosphatidylinositol-calcium pathway.  相似文献   
4.
F Lampert  W R Willems  U Bertram  F Berthold 《Blut》1987,55(2):115-120
In the years 1980-1985 72 children with acute lymphoblastic leukemia were diagnosed and treated by intensive combination chemotherapy (BFM protocols 79, 81, 83). Of these children 33 acquired a Hepatitis B-virus-carrier state with 1983 as the peak year of incidence. Both groups of patients, the infected and the uninfected ones, were comparable as to prognostic factors. All except 8 patients are off chemotherapy after a total duration of treatment of 1 1/2 or 2 years. Probability for event-free survival (life table analysis, maximum observation time 82 months, minimum 12 months) is equal (0.77 vs. 0.75) in both groups. With 3 exceptions, all HBV-infected patients still carry the HBs-antigen in the serum; 22 of the 30 living patients in the infected group developed anti-HBc.  相似文献   
5.
Fucosidosis is an autosomal recessive lysosomal storage disease due to a deficiency of-L-fucosidase activity in tissues and body fluids. Exponentially growing lymphoid cell cultures from four fucosidosis patients had 2.7-fold to 15.6-fold less extracellular-L-fucosidase protein and 28.8-fold to 144.0-fold less intracellular-L-fucosidase protein with negligible catalytic activity, compared to the mean of 19 control cultures. The percentage of total-L-fucosidase protein released extracellularly by cultures from the four patients was 64 to 85%, compared to 35±9% for control cultures. Intracellular and extracellular enzyme forms in fucosidosis and control cell lines were glycoproteins containing polypeptide chains ofM r=52,000. During a 1.5-hr pulse-label with35S-methionine,-L-fucosidase was synthesized by control cells and two fucosidosis cell lines as an intracellular form withM r=58,000. During a subsequent 21-hr chase with unlabeled methionine, mutant enzyme was almost entirely processed to an extracellular form withM r=62,000. In contrast, only 25–30% of control enzyme was processed to an extracellular form (M r=62,000), with the remainder retained intracellularly (M r=60,000). In the other two fucosidosis cell lines,-L-fucosidase was synthesized as an intracellular form withM r=56,000 that was processed to an extracellular form withM r=60,000. In summary, the fucosidosis mutation(s) affected the catalytic activity, quantity, and extracellular release of-L-fucosidase as expressed by lymphoid cells.This work was funded by NIH Grants DK 32161 to R. A. DiCioccio and GM 28428 to J. K. Darby.  相似文献   
6.
Continuous shoot growth monitoring in hydroponics   总被引:1,自引:0,他引:1  
A weighing apparatus for automatic recording of fresh weight of shoots of spinach plants ( Spinacia oleracea L., cv. Subito) growing in nutrient solution is described. The system was tested for 17 days in a controlled environment and enabled the determination of the relative growth rate (RGR) of the shoot fresh weight. Results from three consecutive growth experiments demonstrated diurnal fluctuations in the relative growth rate of the shoot fresh weight. In general, relative growth rates were between 0.32 and 0.36 day−1 16 days after sowing and decreased to between 0.11 and 0.18 day−1 during the 12 following days. The variance between three replicate growth curves was compared with the variance of a growth function fitted through destructively obtained spinach shoot weight data.  相似文献   
7.
The ABA-specific antibody response of A/J mice (Igh Ie) is dominated by the CRIa idiotype. In contrast, BALB/c mice (Igh Ia) do not produce CRIa-bearing anti-ABA antibodies after antigenic challenge. We have shown previously that treatment with rabbit anti-CRIa (R-anti-CRIa) induces the expression of "CRIa-like" anti-arsonate antibodies in BALB/c mice. In the present report, we demonstrate that R-anti-CRIa treatment enables BALB/c mice to respond to A/J ABA-specific first-order suppressor molecules (TsF1). Manipulated BALB/c also produced CRIa bearing ABA-specific immune response. Thus, R-anti-CRIa treatment induces a change in the characteristic Igh restriction pattern typically seen in this system. These data suggest that Igh restriction in the ABA-specific T suppressor cell pathway is the result of CRIa+ dominance in the T suppressor cell response of A/J mice. The effectiveness of idiotypic manipulation in inducing the expression of a given idiotype at both the B cell and T suppressor cell levels is discussed.  相似文献   
8.
Oscillatoria sp. strain 23 is a filamentous, non-heterocystous cyanobacterium that fixes nitrogen aerobically. Although, in this organism nitrogenase is inactivated by oxygen a high tolerance is observed. Up to a pO2 of 0.15 atm, oxygen does not have any measurable effects on acetylene reduction. Higher concentrations of oxygen inhibited the activity to a relatively high degree. Evidence for two mechanisms of oxygen protection of nitrogenase in this cyanobacterium was obtained. A high rate of synthesis of nitrogenase may allow the organism to maintain a certain amount of active enzyme under aerobic conditions. Secondly, a switch off/on mechanism may reversibly convert the active enzyme into a non-active form which is insensitive to oxygen inactivation after a sudden and short-term exposure to high oxygen concentrations. It is conceived that these mechanisms in addition to a temporal separation of nitrogen fixation from oxygenic photosynthesis sufficiently explain the regulation process of aerobic nitrogen fixation in this organism.Abbreviations DCMU 3-(3,4-dichlorophenyl)-1,1-dimethylurea - CAP chloramphenicol  相似文献   
9.
The cyanobacterium Oscillatoria agardhii was grown in continuous culture under various light conditions in order to study the interactions of light on phosphorus-limited growth. Under severe P-limiting (light-saturating) conditions, a low chlorophyll a and C-phycocyanin content was found. In addition, the light-harvesting capacity, reflected in the values of P max (maximum light-saturated oxygen production rate) and (photosynthetic affinity), were low compared to light-limited cultures.Reduction of the light climate, either by reduction of the length of the photoperiod or light-intensity, resulted in an increase in light-harvesting capacity (higher pigment content, P m and ) during growth under P-limiting conditions. Light-induced changes in P max and could be related to the relative growth rate, being the actual growth rate as a fraction of the growth rate which would be observed under light-limiting conditions.Under P-limiting conditions, reduction of the light-climate caused a reduction in dry weight of the culture. This decrease was mainly due to a decrease in carbohydrate content of the cells. Under all conditions tested, carbohydrates were found to accumulate during the light-period and to be consumed during the dark-period.Evaluation of carbohydrate consumption in the dark yielded a specific maintenance rate constant of 0.001 h-1. This observation leads to the conclusion that the specific maintenance rate constant is independent on the character of the growth rate limiting nutrient for O. agardhii.  相似文献   
10.
Summary Lymphocyte-mediated lysis of autologous tumor cells (autologous lymphocyte cytotoxocity ALC) was tested at the time of surgery in 108 patients (46 squamous cell carcinomas of the lung, 25 adenocarcinomas of the lung, 19 soft tissue sarcomas and 18 osteosarcomas). The clinical course of these patients in relation to the test results has been published previously. The group was evaluated again after an extended observation time, now with a mean of 80.2 months (range 36–108). The test was rarely positive in patients with metastasis (2 out of 28 experiments).There was a correlation between the ALC results and the postsurgical clinical course for patients without detectable metastasis in that (1) a negative test was invariably a bad prognostic sign, i.e., all 32 patients with negative ALC died within 3 years (mean survival time 16.1 months). (2) The remission and survival times were longer for the ALC positive patients (p<0.001). (3) All 37 individuals who are alive at present without recurrence belong to the reactive group.The ALC results correlated with the clinical course in 88% of patients. The correlation was highest for the groups of soft tissue sarcoma and adenocarcinoma of the lung. There was no correlation between killing of K562 cells and ALC, or between lymphoproliferative response to PHA and ALC reactivity.  相似文献   
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