74 research outputs found
Review of genetic factors in intestinal malrotation
Intestinal malrotation is well covered in the surgical literature from the point of view of operative management, but few reviews to date have attempted to provide a comprehensive examination of the topic from the point of view of aetiology, in particular genetic aetiology. Following a brief overview of molecular embryology of midgut rotation, we present in this article instances of and case reports and case series of intestinal malrotation in which a genetic aetiology is likely. Autosomal dominant, autosomal recessive, X-linked and chromosomal forms of the disorder are represented. Most occur in syndromic form, that is to say, in association with other malformations. In many instances, recognition of a specific syndrome is possible, one of several examples discussed being the recently described association of intestinal malrotation with alveolar capillary dysplasia, due to mutations in the forkhead box transcription factor FOXF1. New advances in sequencing technology mean that the identification of the genes mutated in these disorders is more accessible than ever, and paediatric surgeons are encouraged to refer to their colleagues in clinical genetics where a genetic aetiology seems likely
Results and Limits of Time Division Multiplexing for the BICEP Array High Frequency Receivers
Time-Division Multiplexing is the readout architecture of choice for many
ground and space experiments, as it is a very mature technology with proven
outstanding low-frequency noise stability, which represents a central challenge
in multiplexing. Once fully populated, each of the two BICEP Array high
frequency receivers, observing at 150GHz and 220/270GHz, will have 7776 TES
detectors tiled on the focal plane. The constraints set by these two receivers
required a redesign of the warm readout electronics. The new version of the
standard Multi Channel Electronics, developed and built at the University of
British Columbia, is presented here for the first time. BICEP Array operates
Time Division Multiplexing readout technology to the limits of its capabilities
in terms of multiplexing rate, noise and crosstalk, and applies them in
rigorously demanding scientific application requiring extreme noise performance
and systematic error control. Future experiments like CMB-S4 plan to use TES
bolometers with Time Division/SQUID-based readout for an even larger number of
detectors.Comment: 10 pages, 7 figures, Submitted to Journal of Low Temperature Physic
Thermal Testing for Cryogenic CMB Instrument Optical Design
Observations of the Cosmic Microwave Background rely on cryogenic
instrumentation with cold detectors, readout, and optics providing the low
noise performance and instrumental stability required to make more sensitive
measurements. It is therefore critical to optimize all aspects of the cryogenic
design to achieve the necessary performance, with low temperature components
and acceptable system cooling requirements. In particular, we will focus on our
use of thermal filters and cold optics, which reduce the thermal load passed
along to the cryogenic stages. To test their performance, we have made a series
of in situ measurements while integrating the third receiver for the BICEP
Array telescope. In addition to characterizing the behavior of this receiver,
these measurements continue to refine the models that are being used to inform
design choices being made for future instruments.Comment: 9 pages, 8 figures, Proceedings of SPIE 202
Diagnosis and management of Cornelia de Lange syndrome:first international consensus statement
Cornelia de Lange syndrome (CdLS) is an archetypical genetic syndrome that is characterized by intellectual disability, well-defined facial features, upper limb anomalies and atypical growth, among numerous other signs and symptoms. It is caused by variants in any one of seven genes, all of which have a structural or regulatory function in the cohesin complex. Although recent advances in next-generation sequencing have improved molecular diagnostics, marked heterogeneity exists in clinical and molecular diagnostic approaches and care practices worldwide. Here, we outline a series of recommendations that document the consensus of a group of international experts on clinical diagnostic criteria, both for classic CdLS and non-classic CdLS phenotypes, molecular investigations, long-term management and care planning
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