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1.
FRAUKE M. MUENZEL MATTHIAS SANETRA WALTER SALZBURGER AXEL MEYER 《Molecular ecology resources》2007,7(6):1048-1050
Eleven microsatellites were isolated from the vairone Leuciscus souffia (Risso 1826), an endangered fish that inhabits river systems in and around the Alps in Europe. The level of genetic diversity was assessed in 29 individuals of the subspecies L. s. souffia, and their variability was further estimated in seven individuals of a different subspecies, L. s. muticellus. Eight of these microsatellite loci were also applied to seven closely related cyprinid species. Availability of the reported microsatellite loci will facilitate the investigation of population genetic structure of these species with applications for the development of conservation strategies and phylogeographical approaches. 相似文献
2.
A Mathematical Model of Photorespiration and Photosynthesis 总被引:2,自引:0,他引:2
A comprehensive mathematical model of C3 leaf carbon metabolism,involving the Calvin cycle and the glycolate and glycerate pathwaysof photorespiration, is formulated in terms of a system of non-lineardifferential equations. A steady state, which is found to beeffectively stable, is derived. The model behaves realisticallywhen tested under varying external carbon dioxide and oxygenconcentrations: photosynthesis is inhibited by higher oxygenlevels, while photorespiration is inhibited by higher carbondioxide levels. Calvin cycle, differential equations, glycolate pathway, mathematical model, photorespiration, photosynthesis 相似文献
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PHILIP S WANG MATTHIAS ANGERMEYER GUILHERME BORGES RONNY BRUFFAERTS WAI TAT CHIU GIOVANNI DE GIROLAMO JOHN FAYYAD OYE GUREJE JOSEP MARIA HARO YUEQIN HUANG RONALD C KESSLER VIVIANE KOVESS DAPHNA LEVINSON YOSHIBUMI NAKANE MARK A OAKLEY BROWN JOHAN H ORMEL JOSé POSADA-VILLA SERGIO AGUILAR-GAXIOLA JORDI ALONSO SING LEE STEVEN HEERINGA BETH-ELLEN PENNELL SOMNATH CHATTERJI T. BEDIRHAN üSTüN 《World psychiatry》2007,6(3):177-185
Data are presented on patterns of failure and delay in making initial treatment
contact after first onset of a mental disorder in 15 countries in the World
Health Organization (WHO)''s World Mental Health (WMH) Surveys. Representative
face-to-face household surveys were conducted among 76,012 respondents aged
18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan,
Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republic
of China (Beijing and Shanghai), Spain, and the United States. The WHO Composite
International Diagnostic Interview (CIDI) was used to assess lifetime DSM-IV
anxiety, mood, and substance use disorders. Ages of onset for individual disorders
and ages of first treatment contact for each disorder were used to calculate
the extent of failure and delay in initial help seeking. The proportion of
lifetime cases making treatment contact in the year of disorder onset ranged
from 0.8 to 36.4% for anxiety disorders, from 6.0 to 52.1% for mood disorders,
and from 0.9 to 18.6% for substance use disorders. By 50 years, the proportion
of lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxiety
disorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% for
substance use disorders. Median delays among cases eventually making contact
ranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 years
for mood disorders, and from 6.0 to 18.0 years for substance use disorders.
Failure and delays in treatment seeking were generally greater in developing
countries, older cohorts, men, and cases with earlier ages of onset. These
results show that failure and delays in initial help seeking are pervasive
problems worldwide. Interventions to ensure prompt initial treatment contacts
are needed to reduce the global burdens and hazards of untreated mental disorders. 相似文献
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GIOVANNA BATTIPAGLIA PAOLO CHERUBINI† MATTHIAS SAURER‡ ROLF T. W. SIEGWOLF‡ SANDRO STRUMIA M. FRANCESCA COTRUFO 《Global Change Biology》2007,13(6):1122-1137
Volcanic eruptions impact the global and the hemispheric climate, but it is still unknown how and to what degree they force the climate system and in particular the global carbon cycle. In this paper, the relationships between individual eruptions (reconstructed for the past using written records), tree primary productivity (estimated using ring widths), photosynthetic rate and stomatal conductance (assessed by carbon and oxygen isotope data) are investigated, to understand the impact of volcanic eruptions on net primary production. Data from a mixed stand of Fagus sylvatica L. and Acer pseudoplatanus L. located in the area of the Vesuvio volcanic complex (Southern Italy) showed a significant decrease in ring width following each eruption. Isotope analyses indicate a change in climatic conditions after such events. Specifically, the lower oxygen isotope ratio in the tree‐ring cellulose strongly suggests an increase in relative humidity and a decrease in temperature, with the latter resulting in a strong limitation to tree‐ring growth. The carbon isotope ratio was only moderately but not significantly reduced in the years of volcanic eruption, suggesting no major changes in C fixation rates. This work is a case study on the effects of volcanic eruptions resulting in strong climatic changes on the local scale. This is an opportunity to explore the process and causal relationships between climatic changes and the response of the vegetation. Thus, we propose here a realistic model scenario, from which we can extrapolate to global scales and improve our interpretations of results of global studies. 相似文献
9.
1. Cyclical parthenogens, organisms switching between sexual and asexual mode of reproduction, are common in aquatic habitats. In permanent waterbodies with year‐round persistence of populations, the relevance of sexually produced resting eggs for population dynamics and structure is still largely unexplored. 2. The aim of this study was to investigate the importance of recruitment from resting eggs to Daphnia spp. in a deep dimictic reservoir with overwintering populations (Saidenbach Reservoir, Germany). We linked field studies on Daphnia population dynamics, hatching rates and diapausing egg abundances in the sediment with allozyme analysis of the genetic variability of both the pelagic population and hatchlings from resting eggs. 3. We found higher hatching rates at intermediate depths (10–18 m), although highest diapausing egg abundances were found in the deeper parts of the reservoir. From the extensive field data, we calculated a population budget for the main basin of the reservoir, which showed that hatched daphnids accounted for <1% of the total abundance and explained only a tiny fraction of population growth. 4. The genetic composition (MultiLocus Genotypes, MLG) of the pelagic population was relatively stable throughout the stratified period with up to five among 39 detected MLGs attaining frequencies >5% per date. From 11 MLGs differentiated among hatched daphnids, three were recovered in the pelagic population in perceptible, albeit low frequencies (1–4%). 5. We conclude that the contribution of hatched animals to the spring population dynamics is negligible in situations with an overwintering population present and will only become relevant if densities are extremely low. In this type of system, the significance of the resting egg bank is presumably mainly related to the maintenance of genetic diversity. 相似文献
10.
CAROLINA CARDOSO LISBOA KLAUS BUTTERBACH‐BAHL MATTHIAS MAUDER RALF KIESE 《Global Change Biology Bioenergy》2011,3(4):277-292
Bioethanol production from sugarcane is discussed as an alternative energy source to reduce dependencies of regional economies on fossil fuels. Even though bioethanol production from sugarcane is considered to be a beneficial and cost‐effective greenhouse gas (GHG) mitigation strategy, it is still a matter of controversy due to insufficient information on the total GHG balance of this system. Aside from the necessity to account for the impact of land use change (LUC), soil N2O emissions during sugarcane production and emissions of GHG due to preharvest burning may significantly impact the GHG balance. Based on a thorough literature review, we show that direct N2O emissions from sugarcane fields due to nitrogen (N) fertilization result in an emission factor of 3.87±1.16% which is much higher than suggested by IPCC (1%). N2O emissions from N fertilization accounted for 40% of the total GHG emissions from ethanol–sugarcane production, with an additional 17% from trash burning. If LUC‐related GHG emissions are considered, the total GHG balance turns negative mainly due to vegetation carbon losses. Our study also shows that major gaps in knowledge still exist about GHG sources related to agricultural management during sugarcane production, e.g. effects of irrigation, vinasse and filter cake application. Therefore, more studies are needed to assess if bioethanol from sugarcane is a viable option to reduce energy‐related GHG emissions. 相似文献