Open and close: Inspired by close‐packing of spheres, to strengthen the framework–H2 interaction in MOFs (metal‐organic frameworks), a strategy is devised to increase the number of nearest ...neighboring open metal sites of each H2‐hosting cage, and to align the open metal sites toward the H2 molecules. Two MOF polymorphs were made, one exhibiting a record high hydrogen uptake of 3.0 wt % at 1 bar and 77 K.
Four reaction parameters and their effects on the formation of cobalt succinate phases were studied by high‐throughput methods. In addition to identifying two new phases, we show that higher reaction ...temperatures lead to products containing less water, more basic conditions favor increasingly condensed M‐O‐M networks (see phase diagram), and depending on the reaction time the products are formed under either kinetic or thermodynamic control.
We demonstrate the synthesis and phase stability of TcN, Tc
2
N, and a substoichiometric TcN
x
from 0 to 50 GPa and to 2500 K in a laser-heated diamond anvil cell. At least potential recoverability ...is demonstrated for each compound. TcN adopts a previously unpredicted structure identified
via
crystal structure prediction.
We demonstrate the synthesis and phase stability of TcN, Tc
2
N, and a substoichiometric TcN
x
from 0 to 50 GPa and to 2500 K in a laser-heated diamond anvil cell.
Five different cobalt succinate materials synthesized from an identical starting mixture using temperature as the only independent variable show increasing condensation and density at higher ...synthesis temperatures.
Autophagic processes play a central role in cellular homeostasis. In pathological conditions, the flow of autophagy can be affected at multiple and distinct steps of the pathway. Current analyses ...tools do not deliver the required detail for dissecting pathway intermediates. The development of new tools to analyze autophagic processes qualitatively and quantitatively in a more straightforward manner is required. Defining all autophagy pathway intermediates in a high-throughput manner is technologically challenging and has not been addressed yet. Here, we overcome those requirements and limitations by the developed of stable autophagy and mitophagy reporter-iPSC and the establishment of a novel high-throughput phenotyping platform utilizing automated high-content image analysis to assess autophagy and mitophagy pathway intermediates.
Models of Alzheimer's disease propose a sequence of amyloid β (Aβ) accumulation, hypometabolism, and structural decline that precedes the onset of clinical dementia. These pathological features ...evolve both temporally and spatially in the brain. In this study, we aimed to characterise where in the brain and when in the course of the disease neuroimaging biomarkers become abnormal.
Between Jan 1, 2009, and Dec 31, 2015, we analysed data from mutation non-carriers, asymptomatic carriers, and symptomatic carriers from families carrying gene mutations in presenilin 1 (PSEN1), presenilin 2 (PSEN2), or amyloid precursor protein (APP) enrolled in the Dominantly Inherited Alzheimer's Network. We analysed 11C-Pittsburgh Compound B (11C-PiB) PET, 18F-Fluorodeoxyglucose (18F-FDG) PET, and structural MRI data using regions of interest to assess change throughout the brain. We estimated rates of biomarker change as a function of estimated years to symptom onset at baseline using linear mixed-effects models and determined the earliest point at which biomarker trajectories differed between mutation carriers and non-carriers. This study is registered at ClinicalTrials.gov (number NCT00869817)
11C-PiB PET was available for 346 individuals (162 with longitudinal imaging), 18F-FDG PET was available for 352 individuals (175 with longitudinal imaging), and MRI data were available for 377 individuals (201 with longitudinal imaging). We found a sequence to pathological changes, with rates of Aβ deposition in mutation carriers being significantly different from those in non-carriers first (across regions that showed a significant difference, at a mean of 18·9 years SD 3·3 before expected onset), followed by hypometabolism (14·1 years 5·1 before expected onset), and lastly structural decline (4·7 years 4·2 before expected onset). This biomarker ordering was preserved in most, but not all, regions. The temporal emergence within a biomarker varied across the brain, with the precuneus being the first cortical region for each method to show divergence between groups (22·2 years before expected onset for Aβ accumulation, 18·8 years before expected onset for hypometabolism, and 13·0 years before expected onset for cortical thinning).
Mutation carriers had elevations in Aβ deposition, reduced glucose metabolism, and cortical thinning compared with non-carriers which preceded the expected onset of dementia. Accrual of these pathologies varied throughout the brain, suggesting differential regional and temporal vulnerabilities to Aβ, metabolic decline, and structural atrophy, which should be taken into account when using biomarkers in a clinical setting as well as designing and evaluating clinical trials.
US National Institutes of Health, the German Center for Neurodegenerative Diseases, and the Medical Research Council Dementias Platform UK.
In this work, we report alkoxy substituted benzil based all organic room temperature phosphors which showed crystallization induced phosphorescence (CIP). Nine title compounds were prepared with ...various alkyl lengths (OC
n
H
2
n
+1
:
n
= 8-16) and the effect of alkyl side group length on the phosphorescence performance was investigated, as compared to
p
-anisil. It was found that both phosphorescence quantum yield and lifetime increased concomitantly as the alkyl length increased up to nonyloxy (
BZL-OC9
). Further increase in the carbon number caused the phosphorescence performance to deteriorate due to greater conformational freedom of the side groups. An incredible quantum yield of 70% was achieved for
BZL-OC9
. A promising finding is that the increased quantum yield was accompanied by the increase in the lifetime relative to
p
-anisil, which has been historically challenging. Single crystallography coupled with UV-Vis spectroscopy revealed that a higher level of intermolecular π-π interactions was observed from
p
-anisil while more alkyl interactions with less intermolecular π-orbital overlap were found for
BZL-OC8
. As a result, molecular rigidification with less phosphorescence quenching was achieved for
BZL-OC8
leading to enhanced performance. A precipitation study on a dichloromethane solution as a function of the content of MeOH (poor solvent) proved that the emission of the BZL-OC
n
system is truly aggregation-induced. The current work demonstrates that strategic side group engineering could be a promising approach to developing high-performance all organic phosphors as well as improving the properties of existing phosphors.
A systematic investigation on the effect of alkyl length on the phosphorescence performances of all organic room-temperature alkoxy substituted benzil phosphors.
Metal(II) formates (Co and Ni) show a significantly larger heat of adsorption for xenon than krypton across all loadings due to size selectivity in the primary adsorption site.
Three magnesium based metal–organic frameworks, Mg3(3,5-PDC)3(DMF)3·DMF 1, Mg(3,5-PDC)(H2O)·(H2O) 3, and Mg4(3,5-PDC)4(DMF)2(H2O)2·2DMF·4.5H2O 4, and a 2-D coordination polymer, Mg(3,5-PDC)(H2O)2 2 ...PDC = pyridinedicarboxylate, were synthesized using a combination of DMF, methanol, ethanol, and water. Compound 1 space group P21/n, a = 12.3475(5) Å, b = 11.1929(5) Å, c = 28.6734(12) Å, β = 98.8160(10)°, V = 3916.0(3) Å3 consists of a combination of isolated and corner-sharing magnesium octahedra connected by the organic linkers to form a 3-D network with a 12.2 Å × 4.6 Å 1-D channel. The channel contains coordinated and free DMF molecules. In compound 2 space group C2/c, a = 9.964(5) Å, b = 12.0694(6) Å, c = 7.2763(4) Å, β = 106.4970(6)°, V = 836.70(6) Å3, PDC connects isolated seven coordinated magnesium polyhedra into a layered structure. Compound 3 space group P6122, a = 11.479(1) Å, c = 14.735(3) Å, V = 1681.7(4) Å3 (previously reported) contains isolated magnesium octahedra connected by the organic linker with each other forming a 3D network. Compound 4 space group P21/c, a = 13.7442(14) Å, b = 14.2887(15) Å, c = 14.1178(14) Å, β = 104.912(2)°, V = 2679.2(5) Å3 also exhibits a 3D network based on isolated magnesium octahedra with square cavities containing both disordered DMF and water molecules. The structural topologies originate due to the variable coordination ability of solvent molecules with the metal center. Water molecules coordinate with the magnesium metal centers preferably over other polar solvents (DMF, methanol, ethanol) used to synthesize the coordination networks. Despite testing multiple desolvation routes, we were unable to measure BET surface areas greater than 51.9 m2/g for compound 1.
An efficient and practical protocol for completely regioselective and highly stereoselective synthesis of vinyldiazaphosphonates from N-heterocyclic phosphine (NHP) and allenes via ...phospha-Michael/intramolecular nucleophilic substitution reaction has been developed. This transformation enabled the synthesis of valuable densely functionalized vinyldiazaphosphonates with a β-, γ-unsaturated ester moiety under mild reaction conditions. Synthetic utility of vinyldiazaphosphonates was demonstrated by a series of synthetic manipulations.
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