1,042 research outputs found
Geographic variation in life-history traits : growth season affects age structure, egg size and clutch size in Andrew’s toad (Bufo andrewsi)
Background: Environmental variation associated with season length is likely to promote differentiation in lifehistory
traits, but has been little studied in natural populations of ectotherms. We investigated patterns of variation
in egg size, clutch size, age at sexual maturity, maximum age, mean age, growth rate and adult body size in
relation to growth season length among 17 populations of Andrew’s toad (Bufo andrewsi) at different latitudes and
altitudes in the Hengduan Mountains, western China.
Results: We found that egg size, age at sexual maturity, and mean age increased with decreasing length of the
growth season, whereas clutch size showed a converse cline. Body size did not increase with decreasing length of
the growth season, but was tightly linked to lifetime activity (i.e. the estimated number of active days during
lifetime). Males and females differed in their patterns of geographic variation in growth rates, which may be the
result of forces shaping the trade-off between growth and reproduction in different environments.
Conclusions: Our findings suggest that growth season plays an important role in shaping variation in life-history
traits in B. andrewsi across geographical gradients
miR-375 suppresses IGF1R expression and contributes to inhibition cell progression in laryngeal squamous cell carcinoma
published_or_final_versio
Entanglement of single-photons and chiral phonons in atomically thin WSe
Quantum entanglement is a fundamental phenomenon which, on the one hand,
reveals deep connections between quantum mechanics, gravity and the space-time;
on the other hand, has practical applications as a key resource in quantum
information processing. While it is routinely achieved in photon-atom
ensembles, entanglement involving the solid-state or macroscopic objects
remains challenging albeit promising for both fundamental physics and
technological applications. Here, we report entanglement between collective,
chiral vibrations in two-dimensional (2D) WSe host --- chiral phonons (CPs)
--- and single-photons emitted from quantum dots (QDs) present in it. CPs which
carry angular momentum were recently observed in WSe and are a
distinguishing feature of the underlying honeycomb lattice. The entanglement
results from a "which-way" scattering process, involving an optical excitation
in a QD and doubly-degenerate CPs, which takes place via two indistinguishable
paths. Our unveiling of entanglement involving a macroscopic, collective
excitation together with strong interaction between CPs and QDs in 2D materials
opens up ways for phonon-driven entanglement of QDs and engineering chiral or
non-reciprocal interactions at the single-photon level
The RhoGEF Trio Functions in Sculpting Class Specific Dendrite Morphogenesis in Drosophila Sensory Neurons
As the primary sites of synaptic or sensory input in the nervous system, dendrites play an essential role in processing neuronal and sensory information. Moreover, the specification of class specific dendrite arborization is critically important in establishing neural connectivity and the formation of functional networks. Cytoskeletal modulation provides a key mechanism for establishing, as well as reorganizing, dendritic morphology among distinct neuronal subtypes. While previous studies have established differential roles for the small GTPases Rac and Rho in mediating dendrite morphogenesis, little is known regarding the direct regulators of these genes in mediating distinct dendritic architectures.Here we demonstrate that the RhoGEF Trio is required for the specification of class specific dendritic morphology in dendritic arborization (da) sensory neurons of the Drosophila peripheral nervous system (PNS). Trio is expressed in all da neuron subclasses and loss-of-function analyses indicate that Trio functions cell-autonomously in promoting dendritic branching, field coverage, and refining dendritic outgrowth in various da neuron subtypes. Moreover, overexpression studies demonstrate that Trio acts to promote higher order dendritic branching, including the formation of dendritic filopodia, through Trio GEF1-dependent interactions with Rac1, whereas Trio GEF-2-dependent interactions with Rho1 serve to restrict dendritic extension and higher order branching in da neurons. Finally, we show that de novo dendritic branching, induced by the homeodomain transcription factor Cut, requires Trio activity suggesting these molecules may act in a pathway to mediate dendrite morphogenesis.Collectively, our analyses implicate Trio as an important regulator of class specific da neuron dendrite morphogenesis via interactions with Rac1 and Rho1 and indicate that Trio is required as downstream effector in Cut-mediated regulation of dendrite branching and filopodia formation
Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay
The decay channel
is studied using a sample of events collected
by the BESIII experiment at BEPCII. A strong enhancement at threshold is
observed in the invariant mass spectrum. The enhancement can be fit
with an -wave Breit-Wigner resonance function with a resulting peak mass of
and a
narrow width that is at the 90% confidence level.
These results are consistent with published BESII results. These mass and width
values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics
Lattice Boltzmann simulations of soft matter systems
This article concerns numerical simulations of the dynamics of particles
immersed in a continuum solvent. As prototypical systems, we consider colloidal
dispersions of spherical particles and solutions of uncharged polymers. After a
brief explanation of the concept of hydrodynamic interactions, we give a
general overview over the various simulation methods that have been developed
to cope with the resulting computational problems. We then focus on the
approach we have developed, which couples a system of particles to a lattice
Boltzmann model representing the solvent degrees of freedom. The standard D3Q19
lattice Boltzmann model is derived and explained in depth, followed by a
detailed discussion of complementary methods for the coupling of solvent and
solute. Colloidal dispersions are best described in terms of extended particles
with appropriate boundary conditions at the surfaces, while particles with
internal degrees of freedom are easier to simulate as an arrangement of mass
points with frictional coupling to the solvent. In both cases, particular care
has been taken to simulate thermal fluctuations in a consistent way. The
usefulness of this methodology is illustrated by studies from our own research,
where the dynamics of colloidal and polymeric systems has been investigated in
both equilibrium and nonequilibrium situations.Comment: Review article, submitted to Advances in Polymer Science. 16 figures,
76 page
Enhanced antibacterial activity of silver nanoparticles/halloysite nanotubes/graphene nanocomposites with sandwich-like structure
A sandwich-like antibacterial reagent (Ag/HNTs/rGO) was constructed through the direct growth of silver nanoparticles on the surface graphene-based HNTs nanosheets. Herein, various nanomaterials were combined by adhesion effect of DOPA after self-polymerization. Ag/HNTs/rGO posses enhanced antibacterial ability against E. coli and S. aureus compared with individual silver nanoparticles, rGO nanosheets or their nanocomposites
A Novel Universal Primer-Multiplex-PCR Method with Sequencing Gel Electrophoresis Analysis
In this study, a novel universal primer-multiplex-PCR (UP-M-PCR) method adding a universal primer (UP) in the multiplex PCR reaction system was described. A universal adapter was designed in the 5′-end of each specific primer pairs which matched with the specific DNA sequences for each template and also used as the universal primer (UP). PCR products were analyzed on sequencing gel electrophoresis (SGE) which had the advantage of exhibiting extraordinary resolution. This method overcame the disadvantages rooted deeply in conventional multiplex PCR such as complex manipulation, lower sensitivity, self-inhibition and amplification disparity resulting from different primers, and it got a high specificity and had a low detection limit of 0.1 ng for single kind of crops when screening the presence of genetically modified (GM) crops in mixture samples. The novel developed multiplex PCR assay with sequencing gel electrophoresis analysis will be useful in many fields, such as verifying the GM status of a sample irrespective of the crop and GM trait and so on
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