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Kidneys from donation after circulatory death (DCD) donors are utilized variably worldwide, in part due to high rates of delayed graft function (DGF) and putative associations with adverse longer-term outcomes. We aimed to determine whether the presence of DGF and its duration were associated with poor longer-term outcomes after kidney transplantation from DCD donors. Using the UK transplant registry, we identified 4714 kidney-only transplants from controlled DCD donors to adult recipients between 2006 and 2016; 2832 recipients (60·1%) had immediate graft function and 1882 (39·9%) had DGF. Of the 1847 recipients with DGF duration recorded, 926 (50·1%) had DGF 7 days, 576 (31·2%) had DGF 7-14 days, and 345 (18·7%) had DGF14 days. After risk adjustment, the presence of DGF was not associated with inferior long-term graft or patient survivals. However, DGF duration of14 days was associated with an increased risk of death-censored graft failure (hazard ratio 1·7, p = ·001) and recipient death (hazard ratio 1·8, p ·001) compared to grafts with immediate function. This study suggests that shorter periods of DGF have no adverse influence on graft or patient survival after DCD donor kidney transplantation and that DGF14 days is a novel early biomarker for significantly worse longer-term outcomes.

Vaccine-induced immune thrombosis and thrombocytopenia (VITT) syndrome is a new entity, characterised by severe thrombocytopenia and multiple sites of thrombosis1 . The presumed mechanism is driven by anti-platelet factor 4 (PF4) antibodies causing platelet activation1 . Donors with VITT syndrome have a particular relevance for liver transplantation (LT), due to the associated risk of passenger lymphocyte syndrome, and a predisposition for porto-mesenteric or hepatic vein thrombosis2 .

Vaccine-induced thrombosis and thrombocytopenia (VITT) may follow immunisation with the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2. Autoantibodies to platelet factor 4 (PF4) may mediate VITT through antibody-dependent platelet activation, though the underlying etiology is uncertain. Anti-PF4 antibodies are also seen in heparin-induced thrombocytopenia, though most cases of VITT do not have prior heparin exposure. More than 20 million people in the United Kingdom (UK) have received the ChAdOx1 nCoV-19 vaccine.

Polyethylene is a widely used plastic exhibiting a large range of properties that depend on molecular weight, crystallinity, chain branching, and cross-linking. In this study, the sound speeds and elastic properties of a variety of commercially available polyethylene materials were experimentally determined using the pulse-echo ultrasound technique. In situ pressure dependent measurements, including ultrasound time of flight, x-ray diffraction, and x-ray radiography, were performed using a Paris-Edinburgh large volume press at the High Pressure Collaborative Access Team (HPCAT), beamline 16-BM-B at the Advanced Photon Source. Polyethylene sound speed and elastic moduli were found to increase with increasing pressure. The zero pressure orthorhombic phase was found to transform to monoclinic at low pressures of ~0.1 GPa.

An acoustic technique for detecting cracks in bismuth telluride (Bi2Te3) thermoelectric wafers is presented. The technique is based on mechanically exciting the wafers with a low frequency pump signal that drives a crack to “breathe” by opening and closing periodically and a high frequency probe signal that interrogates the breathing crack. Interaction between the pump signal, the probe signal, and the crack leads to generation of acoustic nonlinearities in the wafer. In contrast to existing acoustic crack detection techniques we utilize standing waves within the wafers to facilitate simultaneous crack detection throughout the wafer, which reduces the total inspection time; we do not require uniform dimensions and material properties between wafers; and we do not affix the transmitter/receiver to the wafers, which can lead to wafer damage. We present a technique that integrates multiple damage metrics to identify cracks within the wafers. We demonstrate the technique on 94 Bi2Te3 wafers, of which we correctly identify cracked wafers with 4.3% total error and we correctly identify crack-free wafers with 7.5% total error. This acoustic crack detection technique finds application in manufacturing of thermoelectric wafers and other materials, where identifying cracks early in the manufacturing process results in significant time and cost savings. Additionally, this acoustic crack detection technique has implications for other nondestructive inspection applications where cracks cannot be detected effectively through existing techniques.

Highly parallel gene expression profiling has the potential to provide new insight into the molecular mechanisms of complex brain diseases and behavioral traits. We review how gene expression profiling in various brain regions of inbred mouse strains has been used to identify genes that may contribute to strain-specific phenotypes. New data, which demonstrate the use of gene expression profiling in combination with behavioral testing to identify candidate genes involved in mediating variation in running wheel activity, are also presented. These and other studies suggest that a combination of gene expression profiling and more traditional genetic approaches, such as quantitative trait locus analysis, can be used to identify genes responsible for specific neurobehavioral phenotypes.

The vinyl anion ( 2b ) is generated from dimethyl acetylenedicarboxylate by addition of fluoride ion, and this anion reacts with perfluorocyclopentene to give the novel diene ( 5 ). Reactions of ( 5 ) with nucleophiles are described.

A new synthesis of aromatic sulfurpentafluoride compounds is described. Subsequent elaboration of the aromatic rings in the presence of the sulfurpentafluoride group is also discussed for a variety of common synthetic methods. This paper also describes ab initio electronic structure calculations of 3- and 4-aminophenylsulfurpentafluoride, compared with 3- and 4-aminobenzotrifluoride, and presents X-ray crystal structures of two aromatic sulfurpentafluoride derivatives.

In acid media, 1,3-diketones and 1,3-ketoesters can be fluorinated in high yield and often with high conversion mainly to the corresponding 2-fluoro- compounds. Diesters such as diethyl malonate do not react with fluorine under the same reaction conditions. The mechanism of these reactions has been investigated and while the identity of the electrophilic fluorinating species is uncertain, we believe that the essential features of the reaction pathway are understood.

Elemental iodine is slightly soluble in liquid chlorotrifluoroethylene (CTFE) under autogenous pressure at room temperature. Exposure of a mixture of no more than 0.22 mol of iodine with 1 mol of CTFE in a borosilicate glass Carius tube to sunlight, an artificial UV source or to γ-radiation resulted in complete conversion of all the solid iodine initially to ICF2CFClI (1), which was isolated and characterised. The reaction is reversible, the equilibrium constant for I 2 +CTFE liq. ⇌ 1 being ca. 0.22. Thus with light or heat, isolated unconfined 1 reverted to iodine and CTFE. Additional irradiation of 1 confined with excess liquid CTFE led to the irreversible formation of telomers I(CF2CFCl)nI (2). The average value of n in the distribution of telomers increased with dose giving liquids (n = 2–4) or greases (n = 2–10) which were much more stable than 1. Upon bromination, individual telomers in the series Br(CF2CFCl)nBr were isolated and characterised.

Comparison of small-angle X-ray diffraction patterns of Langmuir-Blodgett layers of 1,2-dipalmitoyl-sn-glycero-3-phosphatidic acid on different substrates reveals a small range of values for the monolayer thickness. These are close to the length of the lipid molecule. Polarized attenuated-total-internal-reflection Fourier transform IR spectroscopy shows a high degree of order in the multilayer film, with the alkyl chains approximately parallel to the substrate normal. Together, these results suggest either a very small molecular tilt angle or slight interdigitation of the layers.

Aryl anions of type (1) are potentially useful probes to study the effect of fluorine substituents on charge distributed in an aromatic ring (1a), which is of obvious interest in relation to nucleophilic aromatic substitution. Consequently, we have synthesised a series of stable aryl anions of type Ar F -CXY and the spectra of these systems will be discussed. We will also describe a rational synthesis to a series of novel stable fluorinated cyclopentadienyl anions of general structure (3), via the dienes (2).