The lateral migration of microspheres across streamlines induced by elasticity and inertia in a square microchannel flow of viscoelastic fluids is investigated using a holographic microscopy technique. We experimentally demonstrate the exact particle positions driven by the elasticity of fluid in the channel cross-section. The effects of the blockage ratio, flow rate, and shear-thinning property of the viscoelastic fluids on particle migration are evaluated. In particular, the focusing patterns of microspheres in three-dimensional volume are analyzed under different conditions, namely, dominant inertia, dominant elasticity, and the combined effects of inertia and elasticity. C 2014 AIP Publishing LLC. [http://dx.

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Epitranscriptomic modifications play an important role in RNA function and can impact gene expression. Here, we apply a chemical proteomics approach to investigate readers of N 1methyladenosine (m 1 A), a poorly characterized modification on mammalian mRNA. We find that YTHDF proteins, known m 6 A readers, recognize m 1 A-modified sequences in a methylationspecific manner. We characterize binding of recombinant YTHDF1/2 proteins to m 1 A-modified oligonucleotides to demonstrate that these interactions can exhibit comparable affinity to m 6 Arecognition events, and occur in diverse sequence contexts. Further, we demonstrate YTHDF2 interacts specifically with endogenously modified m 1 A transcripts. Finally, we deplete cellular YTHDF2 to show that the abundance of m 1 A-modified transcripts is increased in its absence. Similarly, increasing m 1 A levels through depletion of ALKBH3, an m 1 A eraser protein, destabilizes known m 1 A-containing RNAs. Our results shed light on the function of m 1 A on mRNA, and provide a mechanistic framework to further evaluate the role of m 1 A in biological processes.

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The carbon (C) and nitrogen (N) storage capabilities of Pinus densiflora in six different stand ages (10, 27, 30, 32, 44, and 71 years old) were investigated in Korea. Thirty sample trees were destructively harvested and 12 were excavated. Samples from the above and belowground tree components, coarse woody debris (CWD), forest floor, and mineral soil (0-30 cm) were collected. Tree biomass was highest in the 71-year-old stand (202.8 t ha(-1)) and lowest in the 10-year-old stand (18.4 t ha(-1)). C and N storage in the mineral soil was higher in the 71-year-old stand than in the other stands, mainly due to higher soil C and N concentrations. Consequently, the total ecosystem C and N storage (tree+forest floor+CWD+soil) was positively correlated with stand age: increasing from a minimum in the 10 year old stand (18.8 t C ha(-1) and 1.3 t N ha(-1)) to a maximum in the 71-year-old stand (201.4 t C ha(-1) and 8.5 t N ha(-1)). The total ecosystem C storage showed a similar sigmoidal pattern to that of tree C storage as a function of the age-sequence, while N storage in the CWD, forest floor and mineral soil showed no significant temporal trends. Our results provide important insights that will increase our understanding of C and N storage in P. densiflora stands and our ability to predict changes according to stand age in the region.

friction coefficient of the polymer solution shows a linear relationship with reduced concentration.

We investigated the influence of stand density [938 tree ha(-1) for high stand density (HD), 600 tree ha(-1) for medium stand density (MD), and 375 tree ha(-1) for low stand density (LD)] on soil CO(2) efflux (R (S)) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R (S) measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature (ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R (S) (t C ha(-1) year(-1)) and leaf litterfall (t C ha(-1) year(-1)) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In addition, R (S) was correlated with ST (R (2) = 0.77-0.80, P < 0.001) and SWC (R (2) = 0.31-0.35, P < 0.001). It appeared that stand density influenced R (S) via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R (2) = 0.71), TBCA (R (2) = 0.64-0.87), and total soil N contents in 2007 (R (2) = 0.94) explained a significant amount of the variance in R (S) (P < 0.01). The current study showed that stand density is one of the key factors influencing R (S) due to the changing biophysical and environmental factors in P. densiflora.

ObjectiveTo evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction.MethodsThirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with pre-adjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed.ResultsBoth groups showed full retraction of the maxillary anterior teeth by controlled tipping and space closure without altered posterior occlusion. However, the preformed C-wire group had a shorter retraction period (by 3.2 months). Furthermore, the maxillary molars in this group showed no significant mesialization, mesial tipping, or extrusion; some mesialization and mesial tipping occurred in the conventional C-wire group.ConclusionsPreformed C-wires combined with maxillary TSADs enable simultaneous leveling and space closure from the beginning of the treatment without maxillary posterior bonding. This allows for faster treatment of dentoalveolar protrusion without unwanted side effects, when compared with conventional C-wire, evidencing its clinical expediency.