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91.
Surveys and questionnaires are regularly used in studies of human–animal relationships. However, little attention has been given to understanding how survey participants are provided with instructions for the selection of a single animal within a multi-pet household, let alone the implications for reporting and interpreting data. We reviewed the instructions for the selection of an individual animal in studies addressing emotional or psychological attachment between people and dogs. By searching multidisciplinary journals from the year 2000 onwards, we identified a total of 128 papers, of which 63 met the inclusion criteria. Where selection criteria/instructions were not clear, authors were contacted. One in five studies (21%, or n = 13) did not report their instructions. When provided, instructions varied considerably. The most commonly provided direction was “favorite/closest relationship” (n = 12, or 19%). The remainder (n = 38, or 60%) were spread across eight different categories. Around half of the studies used a validated questionnaire that already contained an instruction, though a similar proportion of studies implemented author-designed instruments. Overall, the common absence and inconsistency of instructions for individual dog selection is taken to imply that there is no standard expectation or approach for instructions to be reported in studies of human relationships with dogs, or human–animal relationships more generally. We recommend further research on the implication of selection methods to ensure that instructions can be matched with specific research aims. 相似文献
92.
《Ecohydrology》2017,10(4)
Evapotranspiration rates (ET) from contrasting Wisconsin bogs (one forested bog, one open bog) were compared over 4 years by analyzing diel oscillations of their water tables. Daily rates of ET from peatlands were also compared to rates of evaporation (E) from encircled bog ponds. We hypothesized that ET would be higher in the forested bog due to the greater leaf area index of forest canopy relative to moss and ericaceous shrubs. We also hypothesized that ET in peatlands would exceed the physical process of E from encircled ponds. Field data supported the first hypothesis, but the second only proved true for the forested peatland. Daily estimates of peatland ET varied widely, ranging from ~1 to >10 mm/d; but average ET was higher in the forested peatland (4.04 vs. 3.09 mm/d; p < .01). Average ET in the forested peatland was also higher than E during summer (4.04 vs. 3.31 mm/d; p < .05); whereas in the open peatland, average ET was slightly lower than E for all measured seasons (p < .01). Methodologically, the performance of three equations used to estimate ET from daily water table fluctuations was similar. The specific yield of peat (S*y), which is a critical variable in all three equations, was found to be an exponential function of water table depth; and absent an empirically derived S*y, errors in estimates of peatland ET can be large. Given landscape composition across this northern temperate region (13% lakes, 20% peatland, and 54% upland forest) and estimates of forest ET gleaned from the literature, our findings suggest that the regional feedback of water to the atmosphere increases from open waters to peatlands to upland forest, consistent with prior observations that the biological process of transpiration dominates continental ET. 相似文献
93.
Gene flow in crop–wild complexes between phenotypically differentiated ancestors may transfer adaptive genetic variation that alters the fecundity and, potentially, the population growth (λ) of weeds. We created biotypes with potentially invasive traits, early flowering or long leaves, in wild radish (Raphanus raphanistrum) and F5 crop–wild hybrid (R. sativus × R. raphanistrum) backgrounds and compared them to randomly mated populations, to provide the first experimental estimate of long‐term fitness consequences of weedy life‐history variation. Using a life table response experiment design, we modeled λ of experimental, field populations in Pellston, MI, and assessed the relative success of alternative weed strategies and the contributions of individual vital rates (germination, survival, seed production) to differences in λ among experimental populations. Growth rates (λ) were most influenced by seed production, a trait altered by hybridization and selection, compared to other vital rates. More seeds were produced by wild than hybrid populations and by long‐leafed than early‐flowering lineages. Although we did not detect a biotype by selection treatment effect on lambda, lineages also exhibited contrasting germination and survival strategies. Identifying life‐history traits affecting population growth contributes to our understanding of which portions of the crop genome are most likely to introgress into weed populations. 相似文献
94.
The effects of sublethal levels of endosulfan (0, 1, 1.5, 2.5 and 3.3 mg 1–1) on the demography of the rotifer Brachionus calyciorus were studied. Life expectancy at birth (e
o), net reproductive rate (Ro), generation time (T) and intrinsic rate of natural increase (r) were significant differentes between blank controls and controls with acetone. The effective endosulfan concentration at which a given parameter value was reduced to 50% of the controls (EC50) was calculated for life expectancy. 相似文献
95.
Developmental changes in the diurnal water budget of the grape berry exposed to water deficits 总被引:8,自引:0,他引:8
The diurnal water budget of developing grape (Vitis vinifera L.) berries was evaluated before and after the onset of fruit ripening (veraison). The diameter of individual berries of potted ‘Zinfandel’ and ‘Cabernet Sauvignon’ grapevines was measured continuously with electronic displacement transducers over 24 h periods under controlled environmental conditions, and leaf water status was determined by the pressure chamber technique. For well-watered vines, daytime contraction was much less during ripening (after veraison) than before ripening. Daytime contraction was reduced by restricting berry or shoot transpiration, with the larger effect being shoot transpiration pre-veraison and berry transpiration post-veraison. The contributions of the pedicel xylem and phloem as well as berry transpiration to the net diurnal water budget of the fruit were estimated by eliminating phloem or phloem and xylem pathways. Berry transpiration was significant and comprised the bulk of water outflow for the berry both before and after veraison. A nearly exclusive role for the xylem in water transport into the berry was evident during pre-veraison development, but the phloem was clearly dominant in the post-veraison water budget. Daytime contraction was very sensitive to plant water status before veraison but was remarkably insensitive to changes in plant water status after veraison. This transition is attributed to an increased phloem inflow and a partial discontinuity in berry xylem during ripening. 相似文献
96.
Abstract: Populations of northern sea lions ( Eumetopias jubatus ) in the vicinity of Marmot Island, Alaska declined during 1975–1985 at about 5% per year (Merrick et al. 1987). The cause of this decline is not known. A life table for the northern sea lion was calculated assuming that life spans follow a Weibull distribution. Samples of northern sea lions taken in the vicinity of Marmot Island, Alaska during 1975–1978 and 1985–1986 indicate that the average age of females older than 3 yr increased about 1.55 yr (SD = 0.35 yr) while the population was declining at about 5% per year. Fecundity rates decreased by 10% over the same period, but the decrease was not statistically significant (Calkins and Goodwin 1988). Possible causes of the population decline and the change in age structure were examined by writing the Leslie matrix population equation in terms of changes in juvenile and adult survival rates and fecundity, and examining the short–term behavior of the trajectories of the average age of adult females, total number of females, and total number of pups with respect to those changes in the vital parameters. From the observed rate of declines of adults and the changes in average age of adult females and fecundity, estimates of the changes in adult and juvenile survival were calculated; estimates of the standard deviations of these changes were estimated via a bootstrap procedure. One purpose of this exercise is to aid in setting priorities for research for determining the cause of the decline. An explanation for the observed declines in numbers of adult sea lions consistent with the observed fecundity rates, a rate of decrease of 5% in the number of adults, and the corresponding increase in average age (of females age 3 yr and older) was a 10%–20% decrease in the survival of juveniles (age 0-3 yr) coupled with an insignificant change in adult survival (0.03%, SD = 1%). 相似文献
97.
AIMS: Analysis of regulators for modulated gluconic acid production under surface fermentation (SF) condition using grape must as the cheap carbohydrate source, by mutant Aspergillus niger ORS-4.410. Replacement of conventional fermentation condition by solid-state surface fermentation (SSF) for semi-continuous production of gluconic acid by pseudo-immobilization of A. niger ORS-4.410. METHODS AND RESULTS: Grape must after rectification was utilized for gluconic acid production in batch fermentation in SF and SSF processes using mutant strain of A. niger ORS-4.410. Use of rectified grape must led to the improved levels of gluconic acid production (80-85 g l(-1)) in the fermentation medium containing 0.075% (NH4)2HPO4; 0.1% KH2PO4 and 0.015% MgSO4.7H2O at an initial pH 6.6 (+/-0.1) under surface fermentation. Gluconic acid production was modulated by incorporating the 2% soybean oil, 2% starch and 1% H2O2 in fermentation medium at continuously high aeration rate (2.0 l min(-1)). Interestingly, 95.8% yield of gluconic acid was obtained when A. niger ORS-4.410 was pseudo-immobilized on cellulose fibres (bagasse) under SSF. Four consecutive fermentation cycles were achieved with a conversion rate of 0.752-0.804 g g(-1) of substrate into gluconic acid under SSF. CONCLUSIONS: Use of additives modulated the gluconic acid production under SF condition. Semi-continuous production of gluconic acid was achieved with pseudo-immobilized mycelia of A. niger ORS-4.410 having a promising yield (95.8%) under SSF condition. SIGNIFICANCE AND IMPACT OF THE STUDY: The bioconversion of grape must into modulated gluconic acid production under SSF conditions can further be employed in fermentation industries by replacing the conventional carbohydrate sources and expensive, energy consuming fermentation processes. 相似文献
98.
Effects of entomopathogenic fungus Verticillium lecanii on biological characteristics and life table of Serangium japonicum , a predator of whiteflies against five different conidial concentrations (1×104 , 1×105 , 1×106 , 1×107 , and 1×108 conidia/mL) were studied under laboratory conditions. The developmental periods for all immature stages (from eggs, 1st, 2nd, 3rd, 4th instar nymph and pupae up to emergence) among the treatments were significantly different when compared to that of control, and the longest development period was observed as treated with 1×108 spore/mL. However, no significant difference on the percent survival of all immature stages was observed among the treatments and control. Also, there were no significantly different effects of V. lecanii on mean generation time, intrinsic rate, the finite rate of increase and longevity of S. japonicum among the treatments and control. 相似文献
99.
Compant S Kaplan H Sessitsch A Nowak J Ait Barka E Clément C 《FEMS microbiology ecology》2008,63(1):84-93
The colonization pattern of Vitis vinifera L. by Burkholderia phytofirmans strain PsJN was determined using grapevine fruiting cuttings with emphasis on putative inflorescence colonization under nonsterile conditions. Two-week-old rooted plants harbouring flower bud initials, grown in nonsterile soil, were inoculated with PsJN:gfp2x. Plant colonization was subsequently monitored at various times after inoculation with plate counts and epifluorescence and/or confocal microscopy. Strain PsJN was chronologically detected on the root surfaces, in the endorhiza, inside grape inflorescence stalks, not inside preflower buds and flowers but rather as an endophyte inside young berries. Data demonstrated low endophytic populations of strain PsJN in inflorescence organs, i.e. grape stalks and immature berries with inconsistency among plants for bacterial colonization of inflorescences. Nevertheless, endophytic colonization of inflorescences by strain PsJN was substantial for some plants. Microscopic analysis revealed PsJN as a thriving endophyte in inflorescence organs after the colonization process. Strain PsJN was visualized colonizing the root surface, entering the endorhiza and spreading to grape inflorescence stalks, pedicels and then to immature berries through xylem vessels. In parallel to these observations, a natural microbial communities was also detected on and inside plants, demonstrating the colonization of grapevine by strain PsJN in the presence of other microorganisms. 相似文献
100.
Plots of P-values to evaluate many tests simultaneously 总被引:3,自引:0,他引:3