Factors affecting 13C/12C ratios of inland halophytes. II. Ecophysiological interpretations of patterns in the field

1986 ◽  
Vol 64 (11) ◽  
pp. 2700-2707 ◽  
Author(s):  
Robert D. Guy ◽  
David M. Reid ◽  
H. Roy Krouse

By measuring δ13C values, 9 of 42 species inhabiting saline sites in Alberta were found to be C4 plants. None of these, however, are dominant species in wet saline situations. A salinity gradient was studied along a transect to provide improved field data on δ13C variations among C3 halophytes. Soils were dominated by sulphates of sodium and, less so, magnesium. Soil water potential [Formula: see text] was highest at a depth of about 10 cm and, on a daily basis, changed little. The δ13C values of Puccinellia nuttalliana (Schultes) Hitch, were well correlated with [Formula: see text]. The same appeared true for Salicornia europaea L. ssp. rubra (Nels.) Brietung. In a scattergram representing five major species, a close correlation was also evident for Hordeum jubatum L. The relationship could not be extended to Triglochin maritima L. and Sonchus arvensis L., but values for these two species were not separable from those of P. nuttalliana and H. jubatum. Salicornia europaea ssp. rubra, however, differed by having δ13C values that were markedly more negative. Although partly associated with cover by other species, this tendency may reflect a lower water-use efficiency as afforded by a greater reliance on the uptake of readily available salt for osmotic adjustment.

Author(s):  
Александр Викторович Стерхов

The purpose of the article is to build a model for estimating the relative premium in mergers and acquisitions of electric power companies, based on four groups of factors: the company's operating and financial results, the country affiliation, the industry affiliation, the debt market conjuncture. The research methodology is based on a comparative business valuation method. The empirical base of the research includes data on 6504 deals that occurred throughout the world from 1997 to 2018. The research database includes data on both public and non-public companies for which the amount paid in the deal is known, as well as the value of total assets. The scientific novelty consists in clarifying the conceptual apparatus (the concept of relative premium in a deal has been introduced); the selection and grouping of factors affecting the size of the relative premium; identifying and quantifying the influence of variables included in each group of factors. The article proposed the author's approach to the grouping of countries and industries, based on the equality of premium coefficients in the regression and obtained groups of countries and industries with equal premiums. It is shown that the grouping of industries, obtained by the mathematical algorithm, almost completely corresponds to the industry structure of the electric power industry. The coefficient of determination of the final econometric model is more than 20 per cent, which can be estimated as a high-quality assessment. That is because the relative premium, not the amount paid in the deal, is predicted which is in close correlation with the value of the company's assets. The practical significance of the research study consists in the possibility of predicting the value of a business, as well as determining the value paid in a deal in cases where such information is not available in available sources.


1991 ◽  
Vol 69 (11) ◽  
pp. 2497-2502 ◽  
Author(s):  
N. C. Kenkel ◽  
A. L. McIlraith ◽  
C. A. Burchill ◽  
G. Jones

Three grasses (Poa pratensis, Hordeum jubatum, and Puccinellia nuttalliana) were grown in monoculture and three-species mixture at each of eight salinity levels in a controlled environment chamber. In monoculture, all species grew best when no salts were added to the nutrient medium. When salts were added the species showed differing degrees of salt tolerance. Percent decreases in total biomass with increasing salinity and shifts in aboveground to belowground biomass ratios suggested increased salt tolerance in the order P. pratensis < H. jubatum < P. nuttalliana. In mixture, all species showed a significant change in salinity response when compared with their responses in monoculture. Interspecific competition resulted in P. pratensis being suppressed at all but the lowest salinities. Hordeum jubatum showed the least suppression at intermediate salinities, while P. nuttalliana was least suppressed at the highest salinities. These results indicate that interspecific competition results in a shift in the peak performance of more salt-tolerant species toward the high end of the salinity gradient. The species distributions in our experimental mixtures reflected those observed in the field, suggesting that competition plays an important role in structuring inland saline plant communities. Key words: halophyte, glycophyte, community, Hordeum jubatum, Puccinellia nuttalliana, Poa pratensis.


Author(s):  
D. Devkota ◽  
S. C. Dhakal ◽  
D. Dhakal ◽  
D. D. Dhakal ◽  
R. B. Ojha

Vermicompost production technology uses half decomposed organic wastes to feed earthworms which produces nutrient enriched compost. Vermicompost production supports both organic waste management as well as organic farming. A research was conducted with the aim to assess the production and marketing aspect of vermicompost in Chitwan district during the year 2013. Interview schedule was used to collect information from all the 32 vermicompost producers within the study area and 32 adjacent non-producers were selected through snowball sampling. The total respondents' size was 64. The non-producers were farmers with few of them vermicompost users. Training on vermicompost production, group membership and type of farming were the significant factors affecting adoption of vermicompost production technology whereas the volume of earthworm reared and labor use were the significant factors affecting total income from vermicompost production. Resource use efficiency revealed that volume of earthworm reared and material cost were being over utilized but the labor use was underutilized. The volume of earthworm reared and labor use was to be increased by 300 % and 1.48 % respectively to obtain optimum economic advantage.Journal of the Institute of Agriculture and Animal Science. Vol. 33-34, 2015, page:19-26


2016 ◽  
Vol 27 (10) ◽  
pp. 824-838 ◽  
Author(s):  
Vijayalakshmi Easwar ◽  
Joseph Sanfilippo ◽  
Blake Papsin ◽  
Karen Gordon

Background: Children with profound hearing loss can gain access to sound through cochlear implants (CIs), but these devices must be worn consistently to promote auditory development. Although subjective parent reports have identified several factors limiting long-term CI use in children, it is also important to understand the day-to-day issues which may preclude consistent device use. In the present study, objective measures gathered through datalogging software were used to quantify the following in children: (1) number of hours of CI use per day, (2) practical concerns including repeated disconnections between the external transmission coil and the internal device (termed “coil-offs”), and (3) listening environments experienced during daily use. Purpose: This study aimed to (1) objectively measure daily CI use and factors influencing consistent device use in children using one or two CIs and (2) evaluate the intensity levels and types of listening environments children are exposed to during daily CI use. Research Design: Retrospective analysis. Study Sample: Measures of daily CI use were obtained from 146 pediatric users of Cochlear Nucleus 6 speech processors. The sample included 5 unilateral, 40 bimodal, and 101 bilateral CI users (77 simultaneously and 24 sequentially implanted). Data Collection and Analysis: Daily CI use, duration, and frequency of coil-offs per day, and the time spent in multiple intensity ranges and environment types were extracted from the datalog saved during clinic appointments. Multiple regression analyses were completed to predict daily CI use based on child-related demographic variables, and to evaluate the effects of age on coil-offs and environment acoustics. Results: Children used their CIs for 9.86 ± 3.43 hr on average on a daily basis, with use exceeding 9 hr per day in ˜64% of the children. Daily CI use reduced significantly with increasing durations of coil-off (p = 0.027) and increased significantly with longer CI experience (p < 0.001) and pre-CI acoustic experience (p < 0.001), when controlled for the child’s age. Total time in sound (sum of CI and pre-CI experience) was positively correlated with CI use (r = 0.72, p < 0.001). Longer durations of coil-off were associated with higher frequency of coil-offs (p < 0.001). The frequency of coil-offs ranged from 0.99 to 594.10 times per day and decreased significantly with age (p < 0.001). Daily CI use and frequency of coil-offs did not vary significantly across known etiologies. Listening environments of all children typically ranged between 50 and 70 dBA. Children of all ages were exposed to speech in noisy environments. Environment classified as “music” was identified more often in younger children. Conclusions: The majority of children use their CIs consistently, even during the first year of implantation. The frequency of coil-offs is a practical challenge in infants and young children, and demonstrates the need for improved coil retention methods for pediatric use. Longer hearing experience and shorter coil-off time facilitates consistent CI use. Children are listening to speech in noisy environments most often, thereby indicating a need for better access to binaural cues, signal processing, and stimulation strategies to aid listening. Study findings could be useful in parent counseling of young and/or new CI users.


2017 ◽  
Vol 123 ◽  
pp. 135-142 ◽  
Author(s):  
Cherry Myo Lwin ◽  
Sébastien M.R. Dente ◽  
Tao Wang ◽  
Toshiyuki Shimizu ◽  
Seiji Hashimoto

2019 ◽  
Author(s):  
Habtamu Alebachew ◽  
Kebadnew Mulatu ◽  
Mastewal Worku

Abstract Background Globally scabies was among the 50 most common infectious diseases, with a point prevalence 0.3%-46% and in terms of morbidity, at 1.5 million disability-adjusted life years. This study investigate and asses risk factors of scabies in Addet Medhanit Alem yekolo temarie in Yilmana Densa district Amhara, Ethiopia, 2017 Methods Unmatched Case-control study was employed. Fifety five cases from line lists reviewed as per the WHO case definition. Cases were epidemiological linked to previously epidemiological confirmed cases and 118 controls were interviewed with structured questionnaires. Data was entered EPI info version 7 and analyzed by SPSS version 23. Adjusted Odds Ratios and with corresponding 95% confidence intervals were calculated to measure strength of association in multi-variable logistic regression Results The prevalence of scabies was 35%. The mean (SD) age of respondents was 16.4(2.785). Out of respondents 110 (63.6%) used river water for daily basis, 36(20.8%) changed their cloth frequently, 105(60.7%) washed their body frequently, 106(61.3%) had at least one scabies infected person in their house. The odds of scabies infection were 2.3 (AOR = 0.436, 95% CI: 0.205-0.929) times lower among frequent changing of cloth, And washing of body with soap and water were 2.17(AOR = 0.461% CI: 0.214-0.993) times lower having scabies infection. Share cloth was 3(AOR = 3.313, 95% CI: 1.536-7.149) times higher having scabies infection. Presence of scabies infected individuals in the family was 6 (AOR = 6.029, 95% CI: 2.071-14.275) times higher to develop scabies infection. Conclusions There prevalence of scabies infection was high, less than 15 years age group were most affected. Frequent changing of cloth, frequent use of soap for body wash, sharing of cloth and presence of scabies infected individuals in the family were factors affecting scabies infection. Personal, house hygiene should be strength and avail soap for students should be considered.


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