Quadrature decomposition of optical fields using two orthogonal phase sensitive amplifiers

We propose a new technique to optically process coherent signals by simultaneously extracting their two (I and Q) quadrature components into two orthogonal polarizations at the same frequency. Two possible implementations are demonstrated

Efficient binary phase quantizer based on phase sensitive four wave mixing

We experimentally demonstrate an efficient binary phase quantizer operating at low pump powers. Phase-sensitive operation is obtained by polarization mixing the phase-locked signal/idler pair in a degenerate dual-pump vector parametric amplifier

High-energy guanine nucleotides as a signal capable of linking growth to cellular energy status via the control of gene transcription.

This mini-review considers the idea that guanylate nucleotide energy charge acts as an integrative signal for the regulation of gene expression in eukaryotic cells and discusses possible routes for that signal's transduction. Gene expression is intimately linked with cell nutrition and diverse signaling systems serve to coordinate the synthesis of proteins required for growth and proliferation with the prevailing cellular nutritional status. Using short pathways for the inducible and futile consumption of ATP or GTP in engineered cells of Saccharomyces cerevisiae, we have recently shown that GTP levels can also play a role in determining how genes act to respond to changes in cellular energy supply. This review aims to interpret the importance of GTP as an integrative signal in the context of an increasing body of evidence indicating the spatio-temporal complexity of cellular de novo purine nucleotide biosynthesis

Signal regeneration techniques for advanced modulation formats

We review recent results on all-optical regeneration of phase encoded signals based on phase sensitive amplification achieved by avoiding phase-to-amplitude conversion in order to facilitate the regeneration of amplitude/phase encoded (QAM) signals

Novel polarization-assisted phase sensitive optical signal processor requiring low nonlinear phase shifts

We demonstrate a new scheme to achieve binary step-like phase response and high phase-sensitive extinction ratio at low powers. Phase-sensitive operation is achieved by polarization filtering phase-locked signal/idler in a degenerate dual-pump vector parametric amplifier

Investigation into the role of pump to signal power ratio in FWM-based phase preserving amplitude regeneration

We carry out a detailed experimental characterization of a four-wave mixing based amplitude limiter in highly nonlinear fiber based on the Bessel-like power transfer characteristics and highlight trade-offs for phase preserving capabilities

Palliative care medical student education: a cross-sectional medical school survey in mainland China

OBJECTIVE According to the 2015 Quality of Death Index, China ranks 71st in terms of quality of palliative care out of 80 countries. Lack of palliative care education for health professionals is regarded as largely responsible. The study aims to evaluate the status of palliative care education for medical students in mainland China. METHODS A list of all medical schools was obtained from the Ministry of Education. A telephone survey of associate deans responsible for medical education at all 282 medical schools in mainland China was conducted in May 2019, following a standardised protocol. Telephone interviews focused on attitudes to palliative care teaching and the extent and manner in which palliative care is incorporated into the curriculum. RESULTS Associate deans from 173 (61.2%) of the 282 medical schools responded. A total of 120 schools (42.5%) completed the interview, while 53 (18.7%) evaded direct questions related to palliative care. Of the responding deans, 92 (76.7%) regarded palliative care education as very important. However, only 11 (9.2%) provided specific teaching on palliative care. A few schools (n=18) integrated palliative care education within required curricula, such as medical ethics and nursing science. The main reason reported for not providing palliative care education was that the medical curriculum dictated by the Ministry of Education does not require it. CONCLUSION A very small minority of medical schools in mainland China have any formal teaching about palliative care. Clearly, national standards for didactic and clinical teaching in palliative care for medical students and other health professionals are needed

Selenoprotein expression in the rat colon during Se deficiency.

Selenium is an essential trace element, which is present in several proteins, called seleneproteins, that have various biological roles