2,279 research outputs found
Ecosystems as climate controllers – biotic feedbacks (a review)
There is good evidence that higher global temperature will promote a rise of green house gas levels, implying a positive feedback which will increase the effect of the anthropogenic emissions on global temperatures. Here we present a review about the results which deal with the possible feedbacks
between ecosystems and the climate system. There are a lot of types of feedback which are classified.
Some circulation models are compared to each other regarding their role in interactive carbon cycle
Ecology of the Ráckeve-Sorokság Danube – a review
Present paper is a review on the Ráckeve-Soroksár Danube in ecological standpoint. The goal of this study is to collect and evaluate all of available publications in that conception, concerning this
Danube arm. Phytoplankton, zooplankton, macroinvertebrates, vertebrates, macrophytes and also water
chemistry, water management, geographical description are presented. The review comprises the main
studies beginning with the earliest faunistic publications up to the recent ecological, multidisciplinary
investigations. Spatial and temporal patterns likewise water quality are considered as important.
Additionally checklist of aquatic invertebrate and vertebrate fauna are given based on data from literature
The domain of a cannibal dark matter
We consider a scenario in which the dark matter is alone in a hidden sector
and consists of a real scalar particle with a manifest or spontaneously broken
symmetry, at a temperature which differs from the one of the
visible sector, . While similar models with general couplings have
already been studied in the literature, the special case of a model with
spontaneous symmetry breaking constitutes a non-trivial limit of these results,
since it features vanishing tree-level amplitudes for the processes with at threshold, thus making the cross-section governing
dark-matter freeze-out velocity suppressed. We carefully determine the
thermally averaged dark-matter annihilation cross-section in this scenario,
including the possible effects of one-loop corrections and Bose-Einstein
statistics, while also reporting our results in the domain of thermal dark
matter candidates, vs. with being
the hidden-sector temperature at decoupling. We show that for fixed quartic
coupling, due to entropy conservation, the thermal candidates lie along a curve
with anomalous scaling . Furthermore, we demonstrate
that this scaling is valid for a broad class of cannibal DM scenarios, with or
without symmetry breaking. In addition, we also discuss the relevant
cosmological and astrophysical constraints.Comment: 26 pages, 6 figures; v2: added discussion on domain-wall formation,
matches published versio
Introduction to the special issue on Ophthalmic Genetics: Vision in 2020
In this special issue of the American Journal of Medical Genetics, Part C, we explore the ever‐expanding field of Ophthalmic Genetics. The eye is unique among organs for its accessibility to physical examination, permitting exploration of every tissue by slit lamp microscopy, ophthalmoscopy, and imaging including color and autofluorescent photography, ultrasound, optical coherence tomography (OCT), electrophysiology, and adaptive optics confocal and scanning laser ophthalmoscopy. This accessibility permits a variety of surgical and nonsurgical treatments, including the first FDA‐approved gene therapy, voretigene neparvovec‐rzyl for RPE65‐associated Leber Congenital Amaurosis. In this issue, we sought to provide a survey highlighting how heritable ophthalmic disorders are recognizable and accessible to clinical geneticists as well as ophthalmologists
Current range characteristics of Swiss stone pine (Pinus cembra L.) along the Carpathians revealed by chloroplast SSR markers.
We investigated the diversity pattern of nine Swiss stone pine (Pinus cembra L.) populations along the
Carpathian range including the High Tatras, by using six chloroplast DNA microsatellites (cpSSR). Our
aim was to detect genetically distinct regions by clustering of populations, and to tackle possible historical
colonization routes. Our analysis referred to an investigated geographical range with the two most
distant populations situated at about 500 air km. We found that the most diverse populations are situated
at the two edges of the investigated part, in the Retezat Mts. (South Carpathians) and the High Tatras, and
diversity decreases towards the populations of the Eastern Carpathians. Hierarchical clustering and
NMDS revealed that the populations of the South Carpathians with the Tatras form a distinct cluster,
significantly separated from those of the Eastern Carpathians. Moreover, based on the most variable
chloroplast microsatellites, the four populations of the two range edges are not significantly different. Our
results, supported also by palynological and late glacial macrofossil evidences, indicate refugial territories
within the Retezat Mts. that conserved rich haplotype composition. From this refugial territory Pinus
cembra might have colonized the Eastern Carpathians, and this was accompanied by a gradual decrease
in population diversity. Populations of the High Tatras might have had the same role in the colonizing
events of the Carpathians, as positive correlation was detected among populations lying from each other
at a distance of 280 km, the maximum distance between neighbouring populations
The effect of the reproductivity's velocity on the biodiversity of a theoretical ecosystem
Climate change has a great impact on the build and the work of natural ecosystems.
Disappearance of some population or growth of the number in some species can be already caused by
little change in temperature. A Theoretical Ecosystem Growth Model was investigated in order to
examine the effects of various climate patterns on the ecological equilibrium. This paper examines the
diversity of a theoretical ecosystem on the grounds of changing in temperature-climate patterns.
Simulations were made from the simplest case to the more complex exercise to explain harder questions.
Daily temperature values were calculated according to various functions. The effect of existing climate
patterns (historical or future daily temperatures) was analysed where temperature values were from
various climatic zones. In this paper it is examined what kind of environmental conditions result larger
diversity related to the velocity of reproduction
Ocular genetics in the genomics age
Current genetic screening methods for inherited eye diseases are concentrated on the coding exons of known disease genes (gene panels, clinical exome). These tests have a variable and often limited diagnostic rate depending on the clinical presentation, size of the gene panel and our understanding of the inheritance of the disorder (with examples described in this issue). There are numerous possible explanations for the missing heritability of these cases including undetected variants within the relevant gene (intronic, up/down‐stream and structural variants), variants harbored in genes outside the targeted panel, intergenic variants, variants undetectable by the applied technology, complex/non‐Mendelian inheritance, and nongenetic phenocopies. In this article we further explore and review methods to investigate these sources of missing heritability
The zooplankton of the Ráckeve-Soroksár Danube: Spatio-temporal changes and similarity patterns
The Ráckeve-Soroksár Danube has a great importance as it is the second largest side arm in the
Hungarian section of the river Danube and many demands of exploitation are expected. The aim of this
study is to analyse the spatial and temporal changes of the zooplankton (Copepoda, Cladocera)
community in this river arm, moreover the similarity patterns of zooplankton communities in different
Hungarian water bodies are presented in special consideration of the Ráckeve-Soroksár Danube. Basically
this study is based on data from literature, however our data are also used for compiling the database for
the spatio-temporal changes of the Ráckeve-Soroksár Danube. We put emphasis on the three typical
sections of the side arm, as these are stressed due to hydromorphological aspects, but creating artificial
borders are objectionable as well. The results show that both spatial and temporal changes are evident,
what is more, the stagnant water character of the side arm should be underlined
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