Evaluation of ocular blood flow in the assessment of symptomatic carotid stenosis.

BACKGROUND AND PURPOSE: The degree of internal carotid artery (ICA) stenosis determined by criteria from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) is not the most accurate index to assess distal flow compromise. Distal ICA perfusion is also determined by factors such as tandem carotid stenosis and collateral circulation. Quantification of end-organ ocular perfusion using non-invasive laser speckle flowgraphy (LSFG) may provide insights into distal ICA flow. This study prospectively assessed the degree of ICA flow using LSFG. METHODS: Eighteen patients with symptomatic carotid stenosis underwent LSFG evaluation. LSFG was used to extract ocular blood flow metrics recorded simultaneously in the retina, choroid, and optic nerve head. The following ocular flow parameters were measured with LSFG: mean blur rate (MBR), flow acceleration index (FAI), and rising rate (RR). Syngo iFlow perfusion imaging was used to objectively quantify contrast flow in the ICA and brain parenchyma during digital subtraction angiography. Time to peak (TTP) and contrast delay were extracted from seven different regions of interest (ROIs). RESULTS: MBR, FAI, and RR were correlated with NASCET degree of stenosis. FAI and RR also improved after stenting. TTP improved after stenting in three ROIs. A moderate negative correlation was observed between FAI and contrast delay. CONCLUSIONS: LSFG non-invasively quantifies end-organ blood flow distal to the ICA origin. LSFG metrics have the potential to quantify end-organ perfusion and determine if a proximal carotid stenosis is symptomatic.

Small-world complex network generation on a digital quantum processor.

Quantum cellular automata (QCA) evolve qubits in a quantum circuit depending only on the states of their neighborhoods and model how rich physical complexity can emerge from a simple set of underlying dynamical rules. The inability of classical computers to simulate large quantum systems hinders the elucidation of quantum cellular automata, but quantum computers offer an ideal simulation platform. Here, we experimentally realize QCA on a digital quantum processor, simulating a one-dimensional Goldilocks rule on chains of up to 23 superconducting qubits. We calculate calibrated and error-mitigated population dynamics and complex network measures, which indicate the formation of small-world mutual information networks. These networks decohere at fixed circuit depth independent of system size, the largest of which corresponding to 1,056 two-qubit gates. Such computations may enable the employment of QCA in applications like the simulation of strongly-correlated matter or beyond-classical computational demonstrations.

Patient Experiences With Telemedicine in a National Health Service Rheumatology Outpatient Department During Coronavirus Disease-19.

The coronavirus disease-19 pandemic changed rheumatology practice with remote consultations being increasingly utilized where appropriate. We evaluated patient experiences with telephone consultations and report on patient attitudes toward current health care delivery and perspectives of telemedicine in a UK National Health Service rheumatology outpatient department. We analyzed 297 questionnaires from a postal survey conducted during the summer of 2020 after a telephone follow-up consultation. The mean age of respondents was 67 years and 68% were female. The 161 respondents (54%) reported it was their first telephone consultation and overall, 239 (84%) were satisfied with their health assessment. 60% would be happy to have future routine follow-up telephone consultations. Patients advised to shield shared similar satisfaction to the whole sample. However, with increasing age we identified a higher proportion were dissatisfied with telephone consultations and unlikely to have accessibility to video consultation or preferentially opt for this modality.

An Evaluation of Agreement of Breathing Rates Measured by a Novel Device, Manual Counting, and Other Techniques Used in Clinical Practice: Protocol for the Observational VENTILATE Study.

BACKGROUND: Respiratory rate (RR) is the most sensitive physiological observation to predict clinical deterioration on hospital wards, and poor clinical monitoring has been highlighted as a primary contributor to avoidable mortality. Patients in intensive care have their RR monitored continuously, but this equipment is rarely available on general hospital wards. OBJECTIVE: The primary objective is to assess the accuracy of the RespiraSense device in comparison with other methods currently used in clinical practice. The secondary objective is to assess the accuracy of the RespiraSense device in participants in different positions and when reading aloud. METHODS: A single-center, prospective observational study will investigate the agreement of the RespiraSense device as compared with other device measurements (capnography, electrocardiogram) and the current standard measurement of RR (manual counting by a trained health care professional). The different methods will be employed concurrently on the same participant as part of a single study visit. RESULTS: Recruitment to this study has not yet started as funding decisions are still pending. Therefore, results are not available at this stage. It is anticipated that the data required could be collected within 2 months of first recruitment to the study and data analysis completed within 6 months of the study start date. CONCLUSIONS: The Evaluation of Agreement of Breathing Rates Measured by a Novel Device, Manual Counting, and Other Techniques Used in Clinical Practice (VENTILATE) study will provide further validation of the use of the RespiraSense device in subjects with abnormal respiratory rates. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/15437.

RANEY® cobalt--an underutilised reagent for the selective cleavage of C-X and N-O bonds.

RANEY® cobalt, which was first prepared in the 1930s, is known to function effectively as a catalyst for certain chemoselective reductions. However, its utility in chemical synthesis does not seem to have been fully appreciated. This first comprehensive survey of the literature on chemical transformations involving RANEY® cobalt attempts to redress matters by, among other things, highlighting the differences between the performance of this system and its much more well-known but usually less selective congener RANEY® nickel. A reliable method for preparing consistently effective RANEY® cobalt is presented together with a protocol that avoids the need to use it with high pressures of dihydrogen. As such, it is hoped more attention will now be accorded to the title reagent that offers considerable promise as a powerful tool for chemical synthesis, particularly in the assembly of polycyclic frameworks through tandem reductive cyclisation processes.

Synthesis of the enantiomer of the structure assigned to the natural product nobilisitine A.

The synthesis of the enantiomer of the structure, 1, assigned to the natural product nobilisitine A has been accomplished using the enantiomerically pure cis-1,2-dihydrocatechol 4 as starting material. The (1)H and (13)C NMR spectral data derived from compound ent-1 do not match those reported for the natural product, thus suggesting its structure has been incorrectly assigned.

Rapid and enantioselective assembly of the lycorine framework using chemoenzymatic techniques.

The pentacyclic framework associated with the alkaloid (-)-lycorine (1) can be assembled in as few as six steps from the enantiomerically pure cis-1,2-dihydrocatechol 3 which is itself readily available on a large scale through the whole-cell biotransformation of bromobenzene. The methodology has been used in developing the first synthesis of compound 2, a derivative of lycorine.

The creativity of Crumb: research on the effects of psychedelic drugs on the comic art of Robert Crumb.

This article investigates the influence of perception that is altered by psychedelic drugs on processes of creativity through a case study of the work of well-known comic artist Robert Crumb. Samples of Crumb's work before, during, and after the period of his use of psychedelic drugs are content analyzed and compared according to the categorization offered by Janiger and Dobkin de Rios (1989). The results of the comparison indicate that Robert Crumb's drug use significantly altered the stylistic approach of his artwork not only during the period of his drug use, but long after he had stopped using drugs.