L'utilisation de ressources alimentaires avec ou sans composés secondaires connus par une population cyclique de Campagnols des champs (Microtus pennsylvanicus)

1984 ◽  
Vol 62 (4) ◽  
pp. 601-607 ◽  
Author(s):  
Jean-Marie Bergeron
Keyword(s):  
Microtus Pennsylvanicus ◽  
Feeding Habit ◽  
Low Density ◽  
Meadow Voles ◽  
Cost Benefits ◽  
Diet Analyses ◽  
Plant Sampling ◽  
The Cost ◽  
By Products ◽  
Very High

Results from 3 years of plant sampling and diet analyses in a cyclic population of meadow voles (Microtus pennsylvanicus) have shown that animals use a lot of plants with known toxic by-products while the population is in its growth and peak phases, whereas voles from the low density phase of the population almost exclusively eat plants without such by-products. Considering the fact that plants which contain toxic by-products are "bad resources" for herbivores, while plants which do not are "good resources," one can infer from the results that the quantity of good resources available becomes very limited; this explains the appearance of bad resources in the diet at times when the population density becomes very high. There is no evidence in the literature of acute or chronic toxic effects in meadow voles resulting from the ingestion of plants with toxic by-products; thus at present one can only note the importance of such resources in their diet and speculate on the cost–benefits of such a feeding habit.[Journal translation]

Control of Small Mammals on a Hardwood Plantation by Poison-Bait Feeders

1977 ◽  
Vol 53 (2) ◽  
pp. 96-99
Author(s):  
Arthur M. Martell ◽  
Andrew Radvanyi
Keyword(s):  
Small Mammals ◽  
Microtus Pennsylvanicus ◽  
Meadow Vole ◽  
Low Density ◽  
Meadow Voles ◽  
Southern Ontario

Poison-bait feeder stations were placed on a hardwood plantation in southern Ontario in 1973 to attempt long-term control of a meadow vole (Microtus pennsylvanicus) population by continuous dispensing of poisoned grain. Baiting by means of feeders successfully reduced the numbers of meadow voles and maintained them at a low density, about 3-6/ha (1.2-2.4/acre), through April 1976. During the same period, the density of meadow voles on surrounding unpoisoned areas declined from a 1973 peak to about the same as that found on the poisoned plot by fall and winter 1975-76. Despite that low density, less than 4/ha (1.6/acre), severe gnawing and girdling of young hardwoods occurred during winter. Poison-bait feeders are efficient at reducing meadow vole populations from high to low density, but it cannot be assumed that even those low-density populations will not damage hardwood plantations.

Genetic changes in an irradiated population of wild meadow voles (Microtus pennsylvanicus)

1986 ◽  
Vol 64 (3) ◽  
pp. 698-703 ◽  
Author(s):  
Howard A. Ross
Keyword(s):  
Genetic Structure ◽  
Population Growth ◽  
Gamma Radiation ◽  
Radiation Treatment ◽  
Late Summer ◽  
Microtus Pennsylvanicus ◽  
Low Density ◽  
Meadow Voles ◽  
Genetic Characteristics ◽  
And Control

Changes observed in the genetic structure of a wild population of meadow voles (Microtus pennsylvanicus) exposed to chronic gamma radiation are compared with those observed in a nearby unirradiated population. An average exposure of 14.6 ± 0.8 mGy/d of gamma radiation was administered from a 137Cs field irradiator to an otherwise unmanipulated population over 47 weeks. The demographic and genetic characteristics of the populations were estimated by livetrapping and by electrophoresis of the polymorphic plasma proteins encoded by transferrin and leucine aminopeptidase, respectively. Both the irradiated and control populations showed highly synchronous demographic changes: an autumn decline, very low density throughout the winter, a late spring increase, and late summer peak. Allele frequencies and F-statistics fluctuated dramatically throughout the low-density phase. Coincident with the acceleration of population growth, the genetic variables began to converge in the two populations. At the termination of the experiment, when population growth was slowing, the irradiated and control populations were genetically very similar. Sexual activity, longevity, and recruitment were each homogeneous among genotypes in both populations. The radiation treatment had no apparent effect on the genetic structure of the vole population. Gene flow at the beginning of an increase phase is suggested as a possible cause for convergence of the genetic attributes of the irradiated and unirradiated populations.

Planning for Reuse. Developing a Strategy for the Northern Territory, Australia

1991 ◽  
Vol 24 (9) ◽  
pp. 31-43 ◽  
Author(s):  
M. D. Burgess
Keyword(s):  
Potable Water ◽  
Cost Management ◽  
Sewage Treatment ◽  
Northern Territory ◽  
Sewage Effluent ◽  
Cost Benefits ◽  
Management Procedures ◽  
Marketing Activities ◽  
Harsh Climate ◽  
The Cost

A harsh climate, extended dry periods and relatively expensive water resources underly the potential for effluent reuse in the Northern Territory, Australia. The cost of supplying potable water and the potential offsetting effects of utilising sewage effluent are reviewed. The need to firmly establish the true cost to the community of different supply options is identified. Major cost benefits accrue where reuse will enable deferment of either significant potable source augmentation or sewage treatment works upgrading and where horticultural prospects are good at a reuse site close to the treatment works. An overall strategy plan for increasing the potential of reuse is described. This plan includes firm cost management procedures, marketing activities, appropriate land planning measures and a commitment to research and development.

scholarly journals Cost per DALY averted in low, middle- and high-income countries: evidence from the global burden of disease study to estimate the cost-effectiveness thresholds

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Rajabali Daroudi ◽  
Ali Akbari Sari ◽  
Azin Nahvijou ◽  
Ahmad Faramarzi
Keyword(s):  
Cost Effectiveness ◽  
Inverse Correlation ◽  
Gdp Per Capita ◽  
Middle Income ◽  
Capita Health Expenditure ◽  
Per Capita ◽  
Healthcare Interventions ◽  
Disease Study ◽  
The Cost ◽  
Very High

Abstract Background Determining the cost-effectiveness thresholds for healthcare interventions has been a severe challenge for policymakers, especially in low- and middle-income countries. This study aimed to estimate the cost per disability-adjusted life-year (DALY) averted for countries with different levels of Human Development Index (HDI) and Gross Domestic Product (GDP). Methods The data about DALYs, per capita health expenditure (HE), HDI, and GDP per capita were extracted for 176 countries during the years 2000 to 2016. Then we examined the trends on these variables. Panel regression analysis was performed to explore the correlation between DALY and HE per capita. The results of the regression models were used to calculate the cost per DALY averted for each country. Results Age-standardized rate (ASR) DALY (DALY per 100,000 population) had a nonlinear inverse correlation with HE per capita and a linear inverse correlation with HDI. One percent increase in HE per capita was associated with an average of 0.28, 0.24, 0.18, and 0.27% decrease on the ASR DALY in low HDI, medium HDI, high HDI, and very high HDI countries, respectively. The estimated cost per DALY averted was $998, $6522, $23,782, and $69,499 in low HDI, medium HDI, high HDI, and very high HDI countries. On average, the cost per DALY averted was 0.34 times the GDP per capita in low HDI countries. While in medium HDI, high HDI, and very high HDI countries, it was 0.67, 1.22, and 1.46 times the GDP per capita, respectively. Conclusions This study suggests that the cost-effectiveness thresholds might be less than a GDP per capita in low and medium HDI countries and between one and two GDP per capita in high and very high HDI countries.

scholarly journals The Application of Electromagnetic Sensors for Determination of Cherenkov Cone Inside and in the Vicinity of the Detector Volume in Any Environment Known

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 992
Author(s):  
Valeriu Savu ◽  
Mădălin Ion Rusu ◽  
Dan Savastru
Keyword(s):  
Energy Levels ◽  
Cherenkov Detector ◽  
Electromagnetic Sensors ◽  
The Cost ◽  
Information Errors ◽  
The Universe ◽  
Large Frequency ◽  
Very High ◽  
Detector Volume

The neutrinos of cosmic radiation, due to interaction with any known medium in which the Cherenkov detector is used, produce energy radiation phenomena in the form of a Cherenkov cone, in very large frequency spectrum. These neutrinos carry with them the information about the phenomena that produced them and by detecting the electromagnetic energies generated by the Cherenkov cone, we can find information about the phenomena that formed in the universe, at a much greater distance, than possibility of actually detection with current technologies. At present, a very high number of sensors for detection electromagnetic energy is required. Thus, some sensors may detect very low energy levels, which can lead to the erroneous determination of the Cherenkov cone, thus leading to information errors. As a novelty, we propose, to use these sensors for determination of the dielectrically permittivity of any known medium in which the Cherenkov detector is used, by preliminary measurements, the subsequent simulation of the data and the reconstruction of the Cherenkov cone, leading to a significant reduction of problems and minimizing the number of sensors, implicitly the cost reductions. At the same time, we offer the possibility of reconstructing the Cherenkov cone outside the detector volume.

scholarly journals Addition of Flucytosine to Fluconazole for the Treatment of Cryptococcal Meningitis in Africa: A Multicountry Cost-effectiveness Analysis

2019 ◽  
Vol 70 (1) ◽  
pp. 26-29 ◽  
Author(s):  
Tinevimbo Shiri ◽  
Angela Loyse ◽  
Lawrence Mwenge ◽  
Tao Chen ◽  
Shabir Lakhi ◽  
...  
Keyword(s):  
Sensitivity Analysis ◽  
Cost Effectiveness ◽  
Cryptococcal Meningitis ◽  
Cost Effective ◽  
Immunodeficiency Virus ◽  
The Mean ◽  
The Cost ◽  
The Impact ◽  
Costing Analysis ◽  
Very High

Abstract Background Mortality from cryptococcal meningitis remains very high in Africa. In the Advancing Cryptococcal Meningitis Treatment for Africa (ACTA) trial, 2 weeks of fluconazole (FLU) plus flucytosine (5FC) was as effective and less costly than 2 weeks of amphotericin-based regimens. However, many African settings treat with FLU monotherapy, and the cost-effectiveness of adding 5FC to FLU is uncertain. Methods The effectiveness and costs of FLU+5FC were taken from ACTA, which included a costing analysis at the Zambian site. The effectiveness of FLU was derived from cohorts of consecutively enrolled patients, managed in respects other than drug therapy, as were participants in ACTA. FLU costs were derived from costs of FLU+5FC in ACTA, by subtracting 5FC drug and monitoring costs. The cost-effectiveness of FLU+5FC vs FLU alone was measured as the incremental cost-effectiveness ratio (ICER). A probabilistic sensitivity analysis assessed uncertainties and a bivariate deterministic sensitivity analysis examined the impact of varying mortality and 5FC drug costs on the ICER. Results The mean costs per patient were US $847 (95% confidence interval [CI] $776–927) for FLU+5FC, and US $628 (95% CI $557–709) for FLU. The 10-week mortality rate was 35.1% (95% CI 28.9–41.7%) with FLU+5FC and 53.8% (95% CI 43.1–64.1%) with FLU. At the current 5FC price of US $1.30 per 500 mg tablet, the ICER of 5FC+FLU versus FLU alone was US $65 (95% CI $28–208) per life-year saved. Reducing the 5FC cost to between US $0.80 and US $0.40 per 500 mg resulted in an ICER between US $44 and US $28 per life-year saved. Conclusions The addition of 5FC to FLU is cost-effective for cryptococcal meningitis treatment in Africa and, if made available widely, could substantially reduce mortality rates among human immunodeficiency virus–infected persons in Africa.

Molecule-Based Magnets—An Overview

MRS Bulletin ◽  
2000 ◽  
Vol 25 (11) ◽  
pp. 21-30 ◽  
Author(s):  
Joel S. Miller ◽  
Arthur J. Epstein
Keyword(s):  
Low Temperature ◽  
Vapor Deposition ◽  
Room Temperature ◽  
Chemical Vapor ◽  
Magnetic Ordering ◽  
Low Density ◽  
Materials Properties ◽  
The Common ◽  
New Processing ◽  
Very High

Molecule-based magnets are a broad, emerging class of magnetic materials that expand the materials properties typically associated with magnets to include low density, transparency, electrical insulation, and low-temperature fabrication, as well as combine magnetic ordering with other properties such as photoresponsiveness. Essentially all of the common magnetic phenomena associated with conventional transition-metal and rare-earth-based magnets can be found in molecule-based magnets. Although discovered less than two decades ago, magnets with ordering temperatures exceeding room temperature, very high (∼27.0 kOe or 2.16 MA/m) and very low (several Oe or less) coercivities, and substantial remanent and saturation magnetizations have been achieved. In addition, exotic phenomena including photoresponsiveness have been reported. The advent of molecule-based magnets offers new processing opportunities. For example, thin-film magnets can be prepared by means of low-temperature chemical vapor deposition and electrodeposition methods.

Winter coexistence of voles in spruce forest: relevance of seasonal changes in aggression

1975 ◽  
Vol 53 (8) ◽  
pp. 1004-1011 ◽  
Author(s):  
Brian N. Turner ◽  
Michael R. Perrin ◽  
Stuart L. Iverson
Keyword(s):  
Microtus Pennsylvanicus ◽  
Meadow Vole ◽  
Breeding Period ◽  
Spruce Forest ◽  
Vole Population ◽  
Reproductive Condition ◽  
Interspecific Aggression ◽  
Meadow Voles ◽  
Nonbreeding Season ◽  
Short Period

Beginning in November 1973, numerous meadow voles (Microtus pennsylvanicus) moved onto a spruce forest grid occupied by red-backed voles (Clethrionomys gapperi). A resident meadow vole population resulted, the two species coexisting until April 1974, when most meadow voles disappeared from the grid during a relatively short period. Interspecific aggression levels, as determined from voles temporarily removed from the populations and tested in paired encounters in a laboratory arena, were low during the winter, but increased when males of both species entered reproductive condition in the spring. Microtus was generally dominant in early breeding period encounters, but this dominance declined concurrently with the meadow voles' disappearance from the forest. It is argued that meadow voles did not leave the forest to breed, or because the snow cover melted, since this species will live and reproduce in forest in the absence of Clethrionomys. The results are interpreted as support for an earlier hypothesis that competitive habitat exclusion varies seasonally with reproduction-related aggression. Thus, these species apparently may coexist in either of their preferred habitats when interspecific aggression is low (the nonbreeding season), but this relationship terminates when interspecific aggression levels increase with the resumption of breeding in the spring.

Bridging the Technology Transfer Gap

1993 ◽  
Vol 7 (3) ◽  
pp. 176-181 ◽  
Author(s):  
Charles Leonard
Keyword(s):  
Technology Transfer ◽  
Cost Benefits ◽  
Trading Company ◽  
Transfer Of Technology ◽  
Maximum Benefit ◽  
Effective Transfer ◽  
The Cost ◽  
Achieve Maximum Benefit

The cost–benefits of academic–industry alliances are examined as well as the mechanisms to achieve maximum benefit to all the participants. Strategies to ensure the effective transfer of technology from universities to enterprises are reviewed and suggestions on how these might be refined and supported are offered. The article also touches on the role of a university trading company which can be pivotal in enhancing and expanding academic–industry links.

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