242 research outputs found
B meson rare decays in the TNMSSM
We investigate the two loop electroweak corrections to B meson rare decays
and in the minimal
supersymmetry standard model (MSSM) extension with two triplets and one singlet
(TNMSSM). The new particle contents and interactions in the TNMSSM can affect
the theoretical predictions of the branching ratios and , and the corrections
from two loop diagrams to the process can reach
around . Considering the latest experimental measurements, the numerical
results of and in the TNMSSM are presented and analyzed. It
is found that the results in the TNMSSM can fit the updated experimental data
well and the new parameters affect the
theoretical predictions of and obviously
W boson mass in the NP models with extra gauge group
The precise measurement of the W boson mass is closely related to the
contributions of new physics (NP), which can significantly constrain the
parameter space of NP models, particularly those with an additional
local gauge group. The inclusion of a new gauge boson and gauge couplings
in these models can contribute to the oblique parameters , , and W
boson mass at tree level. Taking into account the effects of kinetic mixing, we
calculate and analyze the oblique parameters , , and W boson mass in
such NP models in this study. It is found that the kinetic mixing effects can
make significant contributions to the W boson mass, which can satisfy the
recently measured W boson mass at CDF II or ATLAS by choosing appropriate
values of gauge coupling constants and extra group charges of leptons or
scalar doublets. In addition, if the leptonic Yukawa couplings are invariant
under the extra local gauge group, these contributions can be eliminated
by redefining the gauge boson fields through eliminating the neutral currents
involving charged leptons, even with nonzero kinetic mixing effects.Comment: 11 pages, 2 figure
Induction of Escherichia coli Into a VBNC State by Continuous-Flow UVC and Subsequent Changes in Metabolic Activity at the Single-Cell Level
A viable but non-culturable (VBNC) state of bacteria induced by disinfection in water treatment poses serious health risks because of possible resuscitation of VBNC cells during transportation. In this study, a setup using continuous-flow ultraviolet (UVC) irradiation ranging from 0 to 172.2 mJ cm-2 was designed to simulate real-world disinfection in both drinking water (SDW) and reclaimed water (SRW) treatment plants. A systematic investigation of UVC-induced VBNC bacteria, including occurrence, resuscitation, and time-dependent recovery of metabolic activity during post-incubation, was conducted. Different techniques including two new ones of “single cell culture” and D2O-labeled single-cell Raman spectroscopy were employed to gain comprehensive insights into VBNC cells. Heterotrophic plate counts (HPC) and 5-cyano-2,3-ditoyl tetrazolium chloride flow cytometry (CTC-FCM) assay demonstrated that exposure to continuous-flow UVC can induce E. coli into a VBNC state. Membranes integrity and 16S rRNA transcription level of VBNC bacteria were demonstrated to be unaffected by UVC exposure even at a high dose of 172.2 mJ cm-2. Resuscitation of VBNC bacteria was identified in a more accurate way based on “single cell culture.” Finally, time-dependent evolution of metabolic activity of UVC-treated cells during post-incubation was examined by D2O-labeled Raman spectroscopy at a high-resolution of single-cell level. C-D Raman bands resulting from incorporation of D2O-derived D into bacterial biomass were used as a sensitive and quantitative indicator of bacterial metabolic activity. A lower UVC dose, longer post-incubation time, and higher initial number of bacteria were demonstrated to result in a faster recovery of metabolic activity. Heterogeneous metabolic activity and subpopulation with higher metabolic activity were also revealed by single-cell Raman, even for UVC-treated cells losing cultivability. The comprehensive assessment of VBNC bacteria in UVC-disinfected drinking and reclaimed water points out treatment deficiencies of UVC and the necessity to develop more effective strategies to eliminate VBNC cells
Oosorption in the Endoparasitoid, Pteromalus puparum
Oosorption is the resorption of oocytes in the ovaries, and is usually induced by environmental stress. It has been demonstrated in some insect species, but overall the mechanisms of oosorption are poorly understood. In this study, the oosorption in the endoparasitic wasp, Pteromalus puparum L. (Hymenoptera: Pteromalidae), was observed in response to starvation. To explore the details of oosorption in P. puparum, both levels of hemolymph vitellogenin and ovarian vitellin were determined using sandwich ELISA. The results indicated that both levels of vitellin and total protein in the ovaries were significantly decreased 48 h after eclosion in starved P. puparum, while those of vitellogenin and total protein in the hemolymph were increased. In addition, observation of the ultrastructure of mature oocytes in the ovarioles revealed changes in yolk protein content. Those protein yolk spheres and lipid yolk spheres that had accumulated in the oocytes, were transferred out of the oocytes of starved females. It was assumed that once oosorption was induced in P. puparum, vitellin in the oocytes was transported outside and released into the hemolymph. This information helps to elucidate a mechanism of oosorption in insects
A new species of Trychosis Förster (Hymenoptera, Ichneumonidae, Cryptinae), with a key to the species known from China
A new species of Ichneumonidae, Trychosis naolihense Meng & Ren, sp. nov., is described and illustrated. Specimens were collected from Naolihe National Natural Reserve, Heilongjiang Province, China. A key to the currently known species from China is provided
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