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61.
Ein Grünrezeptor im Drohnenauge (Apis mellifica ♂)   总被引:1,自引:0,他引:1  
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Non-hibernating pikas collect winter food reserves and store them in hay piles. Individualization of alarm calls might allow discrimination between colony members and conspecifics trying to steal food items from a colony pile. We investigated vocal posture, vocal tract length, and individual acoustic variation of alarm calls, emitted by wild-living Altai pikas Ochotona alpina toward a researcher. Recording started when a pika started calling and lasted as long as possible. The alarm call series of 442 individual callers from different colonies consisted of discrete short (0.073–0.157 s), high-frequency (7.31–15.46 kHz), and frequency-modulated calls separated by irregular intervals. Analysis of 442 discrete calls, the second of each series, revealed that 44.34% calls lacked nonlinear phenomena, in 7.02% nonlinear phenomena covered less than half of call duration, and in 48.64% nonlinear phenomena covered more than half of call duration. Peak frequencies varied among individuals but always fitted one of three maxima corresponding to the vocal tract resonance frequencies (formants) calculated for an estimated 45-mm oral vocal tract. Discriminant analysis using variables of 8 calls per series of 36 different callers, each from a different colony, correctly assigned over 90% of the calls to individuals. Consequently, Altai pika alarm calls are individualistic and nonlinear phenomena might further increase this acoustic individualization. Additionally, video analysis revealed a call-synchronous, very fast (0.13–0.23 s) folding, depression, and subsequent re-expansion of the pinna confirming an earlier report of this behavior that apparently contributes to protecting the hearing apparatus from damage by the self-generated high-intensity alarm calls.  相似文献   
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Objective: The aim of this study was to explore the effects of the new traffic safety law on pedestrian mortality by exploring hazardous behaviors of pedestrians in terms of alcohol use and blood alcohol concentration (BAC).

Methods: A retrospective autopsy study was performed, covering a 7-year period (from 2006 to 2012), including cases of fatally injured pedestrians who died at the scene of the incident. Blood samples obtained from the femoral vein during autopsy were analyzed for BAC. The entire sample was divided into 2 groups. The first included cases from 2006 to 2009, at which time the old traffic safety law was in force, and the second included cases from 2010 to 2012, under the new traffic safety law.

Results: A total of 247 cases were examined, covering a 7-year period. The average age was 57.5 ± 19.7 years (median 61.0 years) with a significant male predominance of 147 men to 100 women. This predominance also applied to alcohol use (54 vs. 13). The results show a significant decrease in the total annual number of fatally injured pedestrians, starting from 2009, compared to previous years, reaching a low in 2010, one year after implementation of the new traffic safety law. In contrast, the proportion of alcohol-intoxicated pedestrians showed no significant difference in the years preceding and following the new traffic safety law, nor did the annual distribution of BAC or mean BAC before and after application of the new law.

Conclusion: The present study indicates that the new traffic safety law has been quite effective in reducing pedestrian mortality. However, alcohol consumption and intoxication in pedestrians remains a fairly important factor in motor vehicle accidents involving pedestrians, because the proportion of pedestrians positive for alcohol, the proportion of severely intoxicated pedestrians with BAC > 1 g/L, and annual mean BAC have remained unchanged.  相似文献   

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Composting has been recognized as one of the most cost effective and environmentally sound alternatives for organic wastes recycling from long and composted wastes have a potential to substitute inorganic fertilizers. We investigated the potential of composted tannery sludge for ornamental purposes and to examine the effects of two different composts and concentrations on ornamental Capsicum growth. The two composts were produced with tannery sludge and the composition of each compost was: compost1 of tannery sludge (C1TS) – tannery sludge + sugarcane straw and cattle manure mixed in the ratio 1:3:1 (v:v:v); compost2 of tannery sludge (C2TS) – tannery sludge + “carnauba” straw and cattle manure in the ratio 1:3:1 (v:v:v). Each compost was amended with soil at rates (% v:v) of 0%, 25%, 50%, 75% and 100% (designation hereafter as T1T5, respectively). The number of leaves and fruits were counted, and the stem length was also measured. Chlorophyll content was recorded on three leaves of each harvested plant prior to harvest. Number of leaves and fruits, stem length, dry weight of shoot and roots did not vary significantly between the plants grown in two tannery composts. All the treatments with composted tannery sludge application (T2T5) significantly increased the number of leaves and fruits, stem length and chlorophyll content compared with the control (T1). The chlorophyll content was higher in plants growing in the C1TS compared to C2TS. The results of the present study further suggest that Capsicum may be a good option to be grown on composted tannery amended soil.  相似文献   
66.
This study reports changes in ascorbic acid (AA) in anchoveta eggs, copepods and zooplankton during the 2006, 2007 and 2009 main spawning seasons in the coastal area of the central Humboldt Current System, Chile. Anchoveta eggs, copepods and total zooplankton community shared a seasonal variation and an increasing trend in AA concentration from winter through spring which was associated with the spring diatom bloom. The lineal relationship observed between AA concentration in anchoveta eggs, chlorophyll a and Sea Surface Temperature (SST) suggests that the increase in phytoplankton abundance could also increase the amount of AA in the spawning female anchoveta incorporated through tissue, thus increasing the concentration in their eggs. Ascorbic acid concentrations in copepods presented size (weight) dependence. Small copepods (e.g. Acartia, Oithona) had AA concentrations two orders of magnitude higher than the heavier weight class copepods (e.g. Calanus, Rhincalanus). Results of the determination of glutathione and the antioxidant potential showed a similar trend in interannual variations, suggesting that cold SST conditions observed in the 2007 spawning season could increase the consumption of antioxidants in early stages. Potential connections between AA concentration in the food web on anchoveta reproduction and egg hatching and embryo malformations are discussed.  相似文献   
67.
The chemical composition as well as the water uptake characteristics of aerosols was determined in size-segregated samples collected during November 2002 on the Slovenian coast. Major ions, water-soluble organic compounds (WSOC), short-chain carboxylic acids and trace elements were determined in the water-soluble fraction of the aerosol. Total aerosol black carbon (BC) was measured from filter samples. Our results showed that the origin of air masses is an important factor that controls the variation in the size distribution of the main components. Very high concentrations of WSOC as well as higher concentrations of BC were found under mostly continental influence. Besides the main ionic species (SO4(2-), NH4(+), K+) in the finest size fraction (0.17-0.53 microm), the concentration of NO3(-) was also high. The difference between the two different air mass origins is particularly expressed for Cl-, Na+, Mg2+ and Ca2+ determined in particles larger than 1.6 microm. As expected, a very good correlation was found between Na+ and Cl-. A good correlation was found between sea salt elements and elements of crustal origin (Na+, Cl-, Mg2+, Ca2+, Sr). A good relationship between typical anthropogenic tracers (K, V and Pb) was also observed. The mass growth factors, for all size fractions of aerosols collected under continental influence were very low (maximum 2.23 at 94%, 1.6-5.1 microm), while under marine influence the mass growth factors increased significantly with the particle size. At 97% humidity, the mass growth factors were 6.95 for the size fraction 0.53-1.6 microm and 9.78 for larger particles (1.6-5.1 microm).  相似文献   
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The activity concentrations of natural uranium isotopes (238U and 234U), thorium isotopes (232Th, 230Th and 225Th) and 226Ra were studied in soil and vegetation samples from a disused uranium mine located in the Extremadura region in the south-west of Spain. The results allowed us to characterize radiologically the area close to the installation and one affected zone was clearly manifest as being dependent on the direction of the surface water flow from the mine. The activity concentration mean values (Bq/kg) in this zone were: 10,924, 10,900, 10,075 and 5,289 for 238U, 234U, 230Th and 226Ra, respectively, in soil samples and 1,050, 1,060, 768 and 1,141 for the same radionuclides in plant samples. In an unaffected zone, the activity concentration mean values (Bq/kg) were: 184, 190, 234 and 7251 for 235U, 234U, 230Th and 226Ra, respectively, in soil samples and 28. 29, 31 and 80 in plant samples. The activity concentrations obtained for 232Th and 228Th showed that the influence of the mine was only important for the uranium series radionuclides. The relative radionuclide mobilities were determined from the activity ratios. Correlations between radionuclide activity concentrations and stable element concentrations in the soil samples helped to understand the possible distribution paths for the natural radionuclides.  相似文献   
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