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Jonasson Dreyer posted an update 1 year, 5 months ago
Starting from a general effective Lagrangian for lepton flavor violation (LFV) in quark-lepton transitions, we derive constraints on the effective coefficients from the high-mass tails of the dilepton processes p p → ℓ k ℓ l (with k ≠ l ). The current (projected) limits derived in this paper from LHC data with 36 fb – 1 ( 3 ab – 1 ) can be applied to generic new physics scenarios, including the ones with scalar, vector and tensor effective operators. For purely left-handed operators, we explicitly compare these LHC constraints with the ones derived from flavor-physics observables, illustrating the complementarity of these different probes. While flavor physics is typically more constraining for quark-flavor violating operators, we find that LHC provides the most stringent limits on several flavor-conserving ones. Furthermore, we show that dilepton tails offer the best probes for charm-quark transitions at current luminosities and that they provide competitive limits for tauonic b → d transitions at the high-luminosity LHC phase. As a by-product, we also provide general numerical expressions for several low-energy LFV processes, such as the semi-leptonic decays K → π ℓ k ± ℓ l ∓ , B → π ℓ k ± ℓ l ∓ and B → K ( ∗ ) ℓ k ± ℓ l ∓ .We used bioproxies from paleosoils buried within two aeolian dunes to test hypotheses concerning the origin of dry sandy boreal forests in Canada. These forests are dominated today by Pinus banksiana Lamb. One hypothesis is that too frequent Holocene stand-replacing fires would have transformed the original vegetation through extirpation of susceptible species to fire in water stress habitat. Alternatively, the ecosystem would have not changed since the dunes stabilized enough to support forest establishment. The vegetation composition and richness were determined by identification of charcoal and macroremains and radiocarbon dating for the chronology. Both sites revealed a similar history covering 6400 years. Half of the charcoal layers were less than 2500 years old in both sites, indicating that they had been subjected to the same fire history. Data indicated a stable plant composition and richness, although the percentage of Pinus decreased slightly over 4000 years (decreasing rate 1% per century). The fungus Cenococcum geophilum was consistently present, with a stochastic abundance. The vegetation grew under natural fire conditions and soil dryness since 6000 years. The ecosystem was probably not stressed by late-Holocene fires or climate changes, as the multi-millennial steady state reveals a resistant and resilient ecosystem.Self-diffusion of pure gases including carbon dioxide, methane, ethylene, ethane, and xenon as well as selected two-component mixtures was studied in hybrid zeolitic imidazolate framework-7-8 (ZIF-7-8) crystals using pulsed field gradient (PFG) NMR. This material was formed by mixing 2-methylimidazolate (ZIF-8 linker) and bulkier benzimidazolate (ZIF-7 linker) in the same framework. The intracrystalline diffusion data measured in mixed-linker ZIF-7-8 was compared with the corresponding data in the parent ZIF-8 material. It was found that under the same or comparable experimental conditions the intracrystalline gas diffusion was always slower in ZIF-7-8 than in ZIF-8. This observation is consistent with the expected lower pore aperture size in ZIF-7-8 than in ZIF-8. At the same time, the ethane/ethylene diffusion selectivity was found to be similar in both ZIFs. It was also observed that for the pure studied gases larger than carbon dioxide the diffusivity ratios in ZIF-8 and ZIF-7-8 do not increase with increasing gas size at all loading pressures used. All these data are attributed to greater framework flexibility effects in ZIF-7-8 than ZIF-8. Such effects manifest themselves in a distortion and/or increase in the aperture size in the presence of large sorbates due to linker flexibility.Microfluidics-based reactors enables the controllable synthesis of micro-/nanostructures for a broad spectrum of applications from materials science, bioengineering to medicine. In this study, we first develop a facile and straightforward flow synthesis strategy to control zinc oxide (ZnO) of different shapes (sphere, ellipsoid, short rod, long rod, cube, urchin, and platelet) on a few seconds time scale, based on the 1.5-run spiral-shaped microfluidic reactor with a relative short microchannel length of ca. 92 mm. The formation of ZnO is realized simply by mixing reactants through two inlet flows, one containing zinc nitrate and the other sodium hydroxide. The structures of ZnO are tuned by choosing appropriate flow rates and reactant concentrations of two inlet fluids. The formation mechanism behind microfluidics is proposed. The photocatalysis, cytotoxicity, and piezoelectric capabilities of as-synthesized ZnO from microreactors are further examined, and the structure-dependent efficacy is observed, where higher surface area ZnO structures generally behave better performance. These results bring new insights not only in the rational design of functional micro-/nanoparticles from microfluidics, but also for deeper understanding of the structure-efficacy relationship when translating micro-/nanomaterials into practical applications.Deubiquitinating enzymes (DUBs) regulate the removal of the polyubiquitin chain from proteins targeted for degradation. Current approaches to quantify DUB activity are limited to test tube-based assays that incorporate enzymes or cell lysates, but not intact cells. The goal of this work was to develop a novel peptide-based biosensor of DUB activity that is cell permeable, protease-resilient, fluorescent, and specific to DUBs. The biosensor consists of an N-terminal β-hairpin motif that acts as both a ‘protectide’ to increase intracellular stability and a cell penetrating peptide (CPP) to facilitate the uptake into intact cells. The β-hairpin was conjugated to a C-terminal substrate consisting of the last four amino acids in ubiquitin (LRGG) to facilitate DUB mediated cleavage of a C-terminal fluorophore (AFC). The kinetics of the peptide reporter were characterized in cell lysates by dose response and inhibition enzymology studies. ML324 manufacturer Inhibition studies with an established DUB inhibitor (PR-619) confirmed the specificity of both reporters to DUBs.

