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Abstract Enantioenriched propargylic and allenic derivatives of silicon, germanium, and tin are versatile building blocks for stereoselective synthesis. Consequently, considerable efforts toward their efficient and selective synthesis have been made, both through classical approaches for chirality transfer and catalytic enantioselective strategies that employ the latest developments in transition metal catalysis, organocatalysis, and photoredox catalysis. In this review, we survey broadly applicable synthetic strategies and discuss the scope and mechanistic details for specific protocols that afford these compounds in a regio‐ and stereoselective manner. 

Measuring DNA cytosine methylation excretion presents challenges because methylated cytosine species are released in various forms including free molecules and those bound in DNA fragments. Herein, we report a novel UPLC-MS/MS method that allows the quantification of both free and DNA fragment-bound forms of methylated cytosine species excreted, providing total amounts for each. Cell culture medium and genomic DNA isolated from cells are analyzed to quantify methylated cytosine species. In genomic DNA isolated from MDA-MB-231 breast cancer cells, 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) are detected at 5.1% and 0.07% of total cytosine residues, respectively. In the cell culture medium, only 5hmC is detected at a low level (ca. 7 nM). However, in two normal cell lines (i.e., primary mouse lung epithelial cells and HEK293 kidney cells) 5mC, 5-methylcytidine, and 2′-oxymethylcytidine (but no 5hmC) are found present in cell culture medium at concentrations ranging from 10 to 320 nM. Further, it is observed for the first time that treating MDA-MB-231 cells with carboplatin significantly increases the 5hmC level in the culture medium, indicating a carboplatin-boosted DNA cytosine methylation excretion from cancer cells.Not Available 

Abstract This paper presents a virtual patient generator (VPG) intended to be used for preclinical in silico evaluation of autonomous vasopressor administration algorithms in the setting of experimentally induced vasoplegia. Our VPG consists of two main components: (i) a mathematical model that replicates physiological responses to experimental vasoplegia (induced by sodium nitroprusside (SNP)) and vasopressor resuscitation via phenylephrine (PHP) and (ii) a parameter vector sample generator in the form of a multidimensional probability density function (PDF) using which the parameters characterizing the mathematical model can be sampled. We developed and validated a mathematical model capable of predicting physiological responses to the administration of SNP and PHP. Then, we developed a parameter vector sample generator using a collective variational inference method. In a blind testing, the VPG developed by combining the two could generate a large number of realistic virtual patients (VPs), which could simulate physiological responses observed in all the experiments: on the average, 98.1% and 74.3% of the randomly generated VPs were physiologically legitimate and adequately replicated the test subjects, respectively, and 92.4% of the experimentally observed responses could be covered by the envelope formed by the subject-replicating VPs. In sum, the VPG developed in this paper may be useful for preclinical in silico evaluation of autonomous vasopressor administration algorithms. 

We report an iridium-catalysed stereoselective cyclisation of aryl alkynes with tethered esters and imides to give silyl-protectedO,O- andN,O-acetals. 

Abstract The combination of a geometrically frustrated lattice, and similar energy scales between degrees of freedom endows two-dimensional Kagome metals with a rich array of quantum phases and renders them ideal for studying strong electron correlations and band topology. The Kagome metal, FeGe is a noted example of this, exhibiting A-type collinear antiferromagnetic (AFM) order atT_N ≈ 400 K, then establishes a charge density wave (CDW) phase coupled with AFM ordered moment belowT_CDW ≈ 110 K, and finally forms ac-axis double cone AFM structure aroundT_Canting ≈ 60 K. Here we use neutron scattering to demonstrate the presence of gapless incommensurate spin excitations associated with the double cone AFM structure of FeGe at temperatures well aboveT_CantingandT_CDWthat merge into gapped commensurate spin waves from the A-type AFM order. Commensurate spin waves follow the Bose factor and fit the Heisenberg Hamiltonian, while the incommensurate spin excitations, emerging belowT_Nwhere AFM order is commensurate, start to deviate from the Bose factor aroundT_CDW, and peaks atT_Canting. This is consistent with a critical scattering of a second order magnetic phase transition with decreasing temperature. By comparing these results with density functional theory calculations, we conclude that the incommensurate magnetic structure arises from the nested Fermi surfaces of itinerant electrons and the formation of a spin density wave order.