1,643 research outputs found
N 1,N 2-Bis(6-methyl-2-pyridyl)formamidine
In the crystal structure of the title molecule, C13H14N4, the two pyridyl rings are not coplanar but twisted about the C—N bond with an interplanar angle of 71.1 (1)°. In the crystal, the molecules form dimers, situated on crystallographic centres of inversion, which are connected via a pair of N—H⋯N hydrogen bonds. C—H⋯π-electron ring interactions are also present in the crystal structure. The title molecule adopts an s–cis–anti–s–cis conformation in the solid state
Evasion of HSR in the charmless decays of excited -wave charmonia
We investigate the charmless decays of excited -wave charmonia
and via intermediate
charmed meson loops, where and denote the light vector and pseudoscalar
mesons, respectively. Within the model parameters, the charmed meson loop
contributions are evaluated by using the effective Lagrangian approach. For
, the partial widths of the ,
, and channels can reach to the order of MeV,
while the partial width of the channel is very small and in the
order of keV. For , the partial widths of
turns out to be sizeable, while the
partial widths of is found to be much
smaller than the channel. Our calculations may be examined
by the future BESIII experiments.Comment: 7 pages, 7 figures, to appear in Eur. Phys. J.
Unmasking stem-specific broadly neutralizing epitopes by abolishing N-linked glycosylation sites for vaccine design
Targeting highly conserved HA stem regions has been proposed as a useful strategy for designing universal influenza vaccines. The influenza virus HA stem region, consisting of a HA1 N-terminal part and full HA2 part, contains several potential sites for the addition of N-glycans. We expressed a series of recombinant HA (rHA) mutant proteins with deleted N-linked glycosylation sites in the HA1-stem and HA2-stem regions of H5N1 and pH1N1 viruses. Unmasking N-glycans in the HA2-stem region (rH5HA N484A and rH1HA N503A) did not affect the trimeric structure of HA. Immunizations using rH5HA N484A and rH1HA N503A elicited more potent neutralizing antibody titers against homologous, heterologous and heterosubtypic viruses. Unmasking the HA2-stem N-glycans of rH5HA N484A induced higher levels of stem-specific CR6261-like and FI6v3-like antibodies, improved the ability of stem-specific anti-fusion antibodies, enhanced H5 stem helix A epitope-specific B and T cell responses in splenocytes, and provided better protection against both homologous and heterosubtypic virus challenges. These findings suggest that HA2-stem N-glycan unmasking holds potential as a useful design strategy for developing more broadly protective influenza vaccines
Signs of outflow feedback from a nearby young stellar object on the protostellar envelope around HL Tau
HL Tau is a Class I-II protostar embedded in an infalling and rotating
envelope and possibly associated with a planet forming disk, and it is
co-located in a 0.1 pc molecular cloud with two nearby young stellar objects.
Our ALMA observations revealed two arc-like structures on a 1000 au scale
connected to the disk, and their kinematics could not be explained with any
conventional model of infalling and rotational motions. In this work, we
investigate the nature of these arc-like structures connected to the HL Tau
disk. We conducted new observations in the 13CO and C18O (3-2; 2-1) lines with
JCMT and IRAM 30m, and obtained the ACA data with the 7-m array. With the
single-dish, ACA, and ALMA data, we analyzed the gas motions on both 0.1 pc and
1000 au scales in the HL Tau region. We constructed new kinematical models of
an infalling and rotating envelope with the consideration of relative motion
between HL Tau and the envelope. By including the relative motion between HL
Tau and its protostellar envelope, our kinematical model can explain the
observed velocity features in the arc-like structures. The morphologies of the
arc-like structures can also be explained with an asymmetric initial density
distribution in our model envelope. In addition, our single-dish results
support that HL Tau is located at the edge of a large-scale (0.1 pc) expanding
shell driven by the wind or outflow from XZ Tau, as suggested in the
literature. The estimated expanding velocity of the shell is comparable to the
relative velocity between HL Tau and its envelope in our kinematical model.
These results hints that the large-scale expanding motion likely impacts the
protostellar envelope around HL Tau and affects its gas kinematics. We found
that the mass infalling rate from the envelope onto the HL Tau disk can be
decreased by a factor of two due to this impact by the large-scale expanding
shell.Comment: Accepted by A&
MUSCLE ACTIVATION AND THREE-DIMENSIONAL KINEMATICS OF UPPER EXTREMITY IN SNATCH WEIGHT LIFTING
INTRODUCTION: Previously, there was little weightlifting research focused on biomechanics of the elbow and the shoulder joints (Bartonietz, 1996). Therefore, the purposes of this study were to evaluate the kinematics of upper extremity on sagittal plane during 1st pull, transition from the 1st to the 2nd pull, 2nd pull, turnover under the barbell, catch phase, and rising from the squat position phases of snatch weight lifting and to examine upper-limb muscles activity during snatch weight lifting. The EMG signals were analyzed using the normalized linear envelopes
Splint therapy for disc displacement with reduction of the temporomandibular joint. Part I: Modified mandibular splint therapy
AbstractThe aims of this preliminary study were to present a modified mandibular splint together with a treatment regimen and to evaluate their effects on the treatment of reciprocal joint sounds of the temporomandibular joint (TMJ). The study participants were recruited from 312 consecutive patients in the temporomandibular disorder clinic of a medical center in Taiwan from January 2003 to December 2003. From among these, 59 cases with typical reciprocal clicking were selected for this study. All participants were treated with a modified mandibular splint and then followed up for 6 months. Successful treatment was defined as leading to the disappearance of the joint sounds of TMJ, as described by patients. Based on clinical evaluation, the overall success rate was 71.2% (42/59) with minimal temporary complications. Patients with clicking at less than 3.5cm of interincisal opening had a success rate of 92.5%, which was higher than the success rate of patients with clicking at a mouth opening of 3.5cm or more. This study showed that a modified mandibular splint can be used to treat reciprocal clicking of the TMJ effectively and encouraged us to conduct further study on the efficacy of this splint to treat disc displacement with reduction of TMJ using magnetic resonance imaging examination
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