There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

https://biblio.ugent.be/publication/685594/file/1130605.pdf

Review of Particle Physics

Optical coherence tomography (OCT) has developed rapidly since its first realisation in medicine and is currently an emerging technology in the diagnosis of skin disease. OCT is an interferometric technique that detects reflected and backscattered light from tissue and is often described as the optical analogue to ultrasound. The inherent safety of the technology allows for in vivo use of OCT in patients. The main strength of OCT is the depth resolution. In dermatology, most OCT research has turned on non-melanoma skin cancer (NMSC) and non-invasive monitoring of morphological changes in a number of skin diseases based on pattern recognition, and studies have found good agreement between OCT images and histopathological architecture. OCT has shown high accuracy in distinguishing lesions from normal skin, which is of great importance in identifying tumour borders or residual neoplastic tissue after therapy. The OCT images provide an advantageous combination of resolution and penetration depth, but specific studies of diagnostic sensitivity and specificity in dermatology are sparse. In order to improve OCT image quality and expand the potential of OCT, technical developments are necessary. It is suggested that the technology will be of particular interest to the routine follow-up of patients undergoing non-invasive therapy of malignant or premalignant keratinocyte tumours. It is speculated that the continued technological development can propel the method to a greater level of dermatological use.

https://link.springer.com/content/pdf/bfm%3A978-3-319-06419-2%2F1.pdf

Optical Coherence Tomography

Structural Equations with Latent Variables.

Colouring the snapdragon

Many recent publications have demonstrated the advantages of analysing the spectral content of interferometric outputs[1,2]. They show clearly that by looking at the spectral characteristics of the output from an interferometer illuminated by a white light source, a sensor can be produced requiring no initialisation, and since the frequency response is highly linear, the system may be easily calibrated.

White Light Interferometer Using Linear Ccd Array with Signal Processing

An OCT system is built around a confocal optical receiver by adding a reference beam to the beam returned from the target tissue to the photodetector. The amount of light collected by the OCT receiver (both signal and background signal) depends on the parameters of the confocal receiver. We are interested in a configuration that allows the simultaneous display of the confocal signal and the OCT signal, which requires a separate confocal channel in the system. In this case, the S/N performance is different in the two channels and depends on the optical configuration used. The paper discusses the noise sources in the two channels. S/N ratios are numerically evaluated for cases of experimental interest. As far as the penetration depth in OCT is concerned, a value of 20 optical depths was considered achievable in previous reports if only the shot noise was considered. We correct this value by taking into account the excess photon noise and the limitations imposed by the safety power limits. Multiple scattering determines an increase in noise via the excess photon noise term.

Signal-to-noise ratio in an OCT/confocal system and penetration depth in OCT

Apparatus for measuring the flow of fluid comprising: vortex producing means for producing vortices in the fluid flow, a vortex detector member mounted to be moved by said vortices, movement detector for detecting movement of said vortex detector member, said movement detector comprising: an interferometer having two reflective surfaces, a first one connected to move with the vortex detector member as it is moved by said vortices and the second one mounted stationarily and, means to detect interferometrically relative movement between said two reflective surfaces.

Vortex flowmeter with interferometrical vibration sensor

Background: Clinicians are increasingly recognising severe asthma patients in whom biologicals and other add-on therapies lead to dramatic improvement. There is no agreed upon super-responder (SR) definition at present. Aims: To survey health care professionals using a modified Delphi process in order to define an international consensus-based definition of a severe asthma ‘super-responder’. Methods: The Delphi panel comprised 81 participants (94% specialist pulmonologists or allergists) from 24 countries and consisted of 3 iterative online voting rounds. Consensus on individual items required at least 70% agreement by panel members. Results: Consensus was achieved that the SR definition should be based on improvement across 3 or more domains assessed over a 12 month period. Major SR criteria included exacerbation elimination, a large improvement in asthma control (≥ 2x the minimal clinically important difference) and cessation of maintenance of oral steroids (or weaning to adrenal insufficiency). Minor SR criteria comprised a 75% exacerbation reduction, having well controlled asthma and ≥ 500mL improvement in FEV1. The SR definition needs to also incorporate quality of life measures, though current tools can be difficult to implement in a clinical setting and further research is needed. Conclusions: This international consensus-based definition of severe asthma super responders is an important prerequisite for better understanding super-responder prevalence, predictive factors and the mechanisms involved. Further research is needed to understand the patient perspective and more precisely measure quality of life in super responders.

David A. Jackson

Papers

Colouring the snapdragon

White Light Interferometer Using Linear Ccd Array with Signal Processing

Signal-to-noise ratio in an OCT/confocal system and penetration depth in OCT

Vortex flowmeter with interferometrical vibration sensor

Late Breaking Abstract - Defining a severe asthma super-responder: findings from a Delphi process