26 research outputs found
Magnetic alginate microspheres detected by MRI fabricated using microfluidic technique and release behavior of encapsulated dual drugs
Comparative genomics reveals the hybrid origin of a macaque group
Although species can arise through hybridization, compelling evidence for hybrid speciation has been reported only rarely in animals. Here, we present phylogenomic analyses on genomes from 12 macaque species and show that the fascicularis group originated from an ancient hybridization between the sinica and silenus groups ~3.45 to 3.56 million years ago. The X chromosomes and low-recombination regions exhibited equal contributions from each parental lineage, suggesting that they were less affected by subsequent backcrossing and hence could have played an important role in maintaining hybrid integrity. We identified many reproduction-associated genes that could have contributed to the development of the mixed sexual phenotypes characteristic of the fascicularis group. The phylogeny within the silenus group was also resolved, and functional experimentation confirmed that all extant Western silenus species are susceptible to HIV-1 infection. Our study provides novel insights into macaque evolution and reveals a hybrid speciation event that has occurred only very rarely in primates
Ion-Unquenchable and Thermally “On–Off” Reversible Room Temperature Phosphorescence of 3‑Bromoquinoline Induced by Supramolecular Gels
Ion-unquenchable and thermally on–off
reversible room temperature
phosphorescence (RTP) can be induced by entrapping 3-bromoquinoline
(3-BrQ) into supramolecular gels formed by the self-assembly of a
sorbitol derivative (DBS). In comparison with conventional substrates
inducing RTP, the gel state 3-BrQ/DBS can produce strong RTP due to
the efficient restriction of the vibration of 3-BrQ. Notably, the
rather inconvenient deoxygenation is no longer necessary in the preparation
of 3-BrQ/DBS gels. The produced RTP was found to be very fast to reach
stable, not depending on the standing time. As a reference, in the
liquid state of 3-BrQ/sodium deoxycholate (NaDC), stable RTP can be
observed after standing for 5 h. The investigation of RTP quenching
indicates that the mechanism of RTP induced by DBS gels mainly involves
the microenvironment in which 3-BrQ is located. 3-BrQ was entrapped
in the hydrophobic 3D network structure of DBS gels, thereby restricting
the motion and collision of 3-BrQ and avoiding RTP quenching and additionally
quenching by ions. Furthermore, the RTP of 3-BrQ/DBS gels show an
excellent “on–off” effect at 10 or 80 °C.
This indicates that the solid DBS gel is beneficial for the preparation
of RTP sensor devices
Shape controllable microgel particles prepared by microfluidic combining external ionic crosslinking
Alginate microgels with varied shapes, such as mushroom-like, hemi-spherical, red blood cell-like, and others, were generated by combining microfluidic and external ionic crosslinking methods. This novel method allows a continuous fine tuning of the microgel particles shape by simply varying the gelation conditions, e.g., viscosity of the gelation bath, collecting height, interfacial tension. The release behavior of iopamidol-loaded alginate microgel particles with varied morphologies shows significant differences. Our technique can also be extended to microgels formation from different anionic biopolymers, providing new opportunities to produce microgels with various anisotropic dimensions for the applications in drug delivery, optical devices, and in advanced materials formation
Vorticity Deformation in Polymeric Emulsions Induced by Anisotropic Ellipsoids
We study the influence
of particle shape on shear-induced droplet
deformation in polymeric emulsions. During shearing, droplets become
elongated and rotate periodically about their major axes while aligning
along the vorticity direction in ellipsoid-filled emulsions, while
similar behavior is not observed in the pristine, microsphere-filled
or ellipsoid-filled inverse systems. Based on the Jeffery orbit theory, the formation of anisotropic
droplets with extremely small Reynolds number due to arrested coalescence
in Newtonian matrix and strong confinement effect are suggested to
be responsible for the vorticity alignment of droplets during slow
shearing
Surface modification of Q550 HSLA steel with Co–Fe–Cr composite coatings manufactured by fibre laser cladding
Controlling the Orientation of Droplets in Ellipsoid-Filled Polymeric Emulsions with Particle Parameters and Flow Conditions
The
effect of particle parameters [aspect ratio (AR) and concentration]
and flow conditions (gap spacing and shear rate) on droplet orientation
deformation behavior in polystyrene (PS) particle-filled binary polymeric
emulsions is investigated by using a rheo-optical technique and confocal
microscopy. Interesting vorticity orientation behavior is achieved
by tailoring experimental conditions to yield rigid anisotropic droplets
during slow confined shear flow. PS ellipsoids with a high AR are
found to reside both at the fluid interface in a monolayer side-on
state and inside droplets, leading to the formation of rigid anisotropic
droplets because of the interfacial/bulk jamming effect at appropriate
particle concentrations. In unconfined bulk samples, droplets with
a vorticity orientation can also be observed under the wall migration
effect and confinement effect arising from nearby droplets. However,
the overly strong wall confinement effect remarkably facilitates the
coalescence of vorticity-aligned droplets during slow shear, eventually
leading to the formation of a long stringlike phase aligning along
the flow direction. High shear rates generate refined droplets with
lower particle coverage and weak rigidity, which restrain the formation
of anisotropic droplets and thus suppress the droplet vorticity orientation
Conducting Hydrogels of Tetraaniline-g-poly(vinyl alcohol) in Situ Reinforced by Supramolecular Nanofibers
Novel conducting hydrogels (PVA-TA)
with dual network structures were synthesized by the grafting reaction
of tetraaniline (TA) into the main chains of polyÂ(vinyl alcohol) and
in situ reinforced by self-assembly of a sorbitol derivative as the
gelator. The chemical structure of the PVA-TA hydrogels was characterized
by using FT-IR and NMR. The mechanical strength of the PVA-TA hydrogels
was strongly improved due to the presence of supramolecular nanofibers.
For instance, the compressive and tensile strengths of supramolecular
nanofiber-reinforced hydrogels were, respectively, 10 times and 5
times higher than those of PVA-TA hydrogels. Their storage modulus
(G′) and loss modulus (G″) were 5 times and 21 times
higher than those of PVA-TA hydrogels, respectively. Cyclic voltammetry
and conductivity measurements indicated that the electroactivity of
reinforced hydrogels is not influenced by the presence of supramolecular
nanofibers