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We demonstrate the feasibility of probing the charged lepton-flavor-violating decay mu+ -> e+ X0 for the presence of a slow-moving neutral boson X0 capable of undergoing gravitational binding to large structures and, as such, able to participate in some cosmological scenarios. A short exposure to surface antimuons from beam line M20 at TRIUMF generates a branching ratio limit of <1E-5. This is comparable to or better than previous searches for this channel, although in a thus- far-unexplored region of X0 phase space very close to the kinematic limit of the decay, where m_X0 approaches m_mu+ . The future improved sensitivity of the method using a customized p-type point-contact germanium detector is described. 

We report the synthesis and characterization of two phosphine gold carbinol species designed to support intramolecular Au⋯H–O hydrogen bonding. Increasing the metallobasicity of gold through chloride to phenyl ligand substitution produced an observable increase in this hydrogen bond's strength which was analyzed experimentally and computationally. 

Abstract Achieving long‐term retention of pop‐up satellite archival tags (PSATs) has proven difficult for all fishes but is particularly challenging for small migrant species due to the relatively large size of tags. In this study, the authors tested the latest and smallest PSAT model on the market, the mark‐report satellite tag (mrPAT), and developed a simple, cost‐effective method of tag attachment on sheepshead Archosargus probatocephalus (Walbaum 1792), a small marine fish. During laboratory trials, the method of tag attachment used in this study outperformed the existing methods with two c . 40 cm fish retaining their tags for 3 months (the duration of the laboratory study). During field deployments, data were successfully obtained for 17 of the 25 tagged fish [37–50 cm fork length (FL)]. Of these, 14 tags (82%) remained on the fish until the pre‐programmed release date resulting in tag retention times of up to 172 days (mean: 140 days). The investigation represents the first extensive study into the feasibility of PSATs for monitoring fishes in this size range. The authors demonstrate that their method of attachment and this latest PSAT model are feasible for c . 5‐month deployments on fishes that are relatively small ( c . 45 cm FL). These results with A. probatocephalus represent a potentially significant advance in PSAT methodology for fishes of this size. Future investigations are needed to determine if this method is transferrable to other species in the same size range. 

Controlling the reactivity of transition metal complexes by positioning non-innocent functionalities around the catalytic pocket is a concept that has led to significant advances in catalysis. Here we describe our efforts toward the synthesis of dicationic phosphine gold complexes of general formula [( o -Ph 2 P(C 6 H 4 )Carb)Au(tht)] 2+ decorated by a carbenium moiety (Carb) positioned in the immediate vicinity of the gold center. While the most acidic examples of such compounds have limited stability, the dicationic complexes with Carb + = 9- N -methylacridinium and Carb + = [C(Ar N ) 2 ] + (Ar N = p -(C 6 H 4 )NMe 2 ) are active as catalysts for the cycloisomerization of N -propargyl-4-fluorobenzamide, a substrate chosen to benchmark reactivity. The dicationic complex [( o -Ph 2 P(C 6 H 4 )C(Ar N ) 2 )Au(tht)] 2+ , which also promotes hydroarylation and enyne cyclization reactions, displays a higher catalytic activity than its acridinium analog, indicating that the electrophilic reactivity of these complexes scales with the Lewis acidity of the carbenium moiety. These results support the role of the carbenium unit as a non-innocent functionality which can readily enhance the activity of the adjacent metal center. Finally, we also describe our efforts toward the generation and isolation of free γ-cationic phosphines of general formula [( o -Ph 2 P(C 6 H 4 )Carb)] + . While cyclization into phosphonium species is observed for Carb + = [C(Ar N ) 2 ] + , [C(Ph)(Ar N )] + , and 9-xanthylium, [( o -Ph 2 P(C 6 H 4 )-9- N -methylacridinium)] + can be isolated as an air stable, biphilic derivative with uncompromised Lewis acidic and basic properties. 

Abstract KRAS is the most frequently mutated oncogene in human lung adenocarcinomas (hLUAD), and activating mutations frequently co-occur with loss-of-function mutations in TP53 or STK11/LKB1. However, mutation of all three genes is rarely observed in hLUAD, even though engineered comutation is highly aggressive in mouse lung adenocarcinoma (mLUAD). Here, we provide a mechanistic explanation for this difference by uncovering an evolutionary divergence in the regulation of triosephosphate isomerase (TPI1). In hLUAD, TPI1 activity is regulated via phosphorylation at Ser21 by the salt inducible kinases (SIK) in an LKB1-dependent manner, modulating flux between the completion of glycolysis and production of glycerol lipids. In mice, Ser21 of TPI1 is a Cys residue that can be oxidized to alter TPI1 activity without a need for SIKs or LKB1. Our findings suggest this metabolic flexibility is critical in rapidly growing cells with KRAS and TP53 mutations, explaining why the loss of LKB1 creates a liability in these tumors. Significance:Utilizing phosphoproteomics and metabolomics in genetically engineered human cell lines and genetically engineered mouse models (GEMM), we uncover an evolutionary divergence in metabolic regulation within a clinically relevant genotype of human LUAD with therapeutic implications. Our data provide a cautionary example of the limits of GEMMs as tools to study human diseases such as cancers.This article is highlighted in the In This Issue feature, p. 799