Shot noise limited heterodyne detection of CARS signals

We demonstrate heterodyne detection of CARS signals using a cascaded phase-preserving chain to generate the\ud CARS input wavelengths and a coherent local oscillator. The heterodyne ampli¯cation by the local oscillator re-\ud veals a window for shot noise limited detection before the signal-to-noise is limited by amplitude °uctuations. We\ud demonstrate an improvement in sensitivity by more than 3 orders of magnitude for detection using a photodiode.\ud This will enable CARS microscopy to reveal concentrations below the current mMolar range

Type 2 diabetes and COPD: treatment in the right healthcare setting? An observational study

Background: Type 2 diabetes (T2DM) and COPD are chronic medical conditions, for which patients need lifelong healthcare. The aim of this study is to examine in which healthcare setting patients with T2DM and COPD receive their care, and if this is the correct healthcare setting according to guidelines. Method: T2DM and COPD patients from five primary care practices were included. Data concerning healthcare setting and patient- and clinical characteristics were extracted from the electronic medical records. Patient profiles treated in primary care were compared with the profiles of those treated in secondary care. In patients treated in secondary care we evaluated whether treatment allocation was according to the guidelines and if back-referral to primary care should take place. Results: Of the T2DM and COPD patients 7.6% and 29.6% respectively, were treated in secondary care, and 72.7% respectively 31.4% of these were according to the guideline. T2DM patients treated in primary care were older (63 versus 57 years, p < 0.01, had a shorter diabetes duration (8 versus 11 years, p < 0.01) and lower HbA1c (53.0 versus 63.5 mmol/l, p < 0.01) than those treated in secondary care. Those with COPD treated in primary care used less inhalation medication (75.2 versus 90.1%, p < 0.01) and had better spirometry results (67.39 versus 57.53 FEV 1%pred, p < 0.01). Conclusion: The majority of the patients with T2DM and COPD were correctly treated in primary care and on average patients with a better health condition were treated in primary care. Also, those who were treated in secondary care were most of the time treated in the correct treatment setting according to the guidelines

‘Dead people don’t claim’: A psychopolitical autopsy of UK austerity suicides

One of the symptoms of post financial crisis austerity in the UK has been an increase in the numbers of suicides, especially by people who have experienced welfare reform. This article develops and utilises an analytic framework of psychopolitical autopsy to explore media coverage of ‘austerity suicide’ and to take seriously the psychic life of austerity (internalisation, shame, anxiety), embedding it in a context of social dis-ease. Drawing on three distinct yet interrelated areas of literature (the politics of affect and psychosocial dynamics of welfare, post and anti-colonial psychopolitics, and critical suicidology), the article aims to better understand how austerity ‘kills’. Key findings include understanding austerity suicides as embedded within an affective economy of the anxiety caused by punitive welfare retrenchment, the stigmatisation of being a recipient of benefits, and the internalisation of market logic that assigns value through ‘productivity’ and conceptualises welfare entitlement as economic ‘burden’. The significance of this approach lies in its ability to widen analytic framing of suicide from an individual and psychocentric focus, to illuminate culpability of government reforms while still retaining the complexity of suicide, and thus to provide relevant policy insights about welfare reform

SARS-CoV-2 Infection in Patients With Waldenström's Macroglobulinemia: A Multicenter International Cohort Study

The coronavirus disease 2019 (COVID-19) pandemic has represented a huge challenge for vulnerable patients affected with hematological malignancies.1,2 So far, heterogeneous series on patients with lymphoma and COVID-19 have been published with mortality rates ranging from 25% to 40%,3–8 with only limited information about specific neoplasms.Peer reviewe

Noise in stimulated Raman scattering measurement: From basics to practice

International audienc

Decay kinetics and quantum yields of fluorescence in photosystem I from Synechococcus elongatus with P700 in the reduced and oxidized state: are the kinetics of excited state decay trap-limited or transfer-limited?

Transfer and trapping of excitation energy in photosystem I (PS I) trimers isolated from Synechococcus elongatus have been studied by an approach combining fluorescence induction experiments with picosecond time-resolved fluorescence measurements, both at room temperature (RT) and at low temperature (5 K). Special attention was paid to the influence of the oxidation state of the primary electron donor P700. A fluorescence induction effect has been observed, showing a approximately 12% increase in fluorescence quantum yield upon P700 oxidation at RT, whereas at temperatures below 160 K oxidation of P700 leads to a decrease in fluorescence quantum yield ( approximately 50% at 5 K). The fluorescence quantum yield for open PS I (with P700 reduced) at 5 K is increased by approximately 20-fold and that for closed PS I (with P700 oxidized) is increased by approximately 10-fold, as compared to RT. Picosecond fluorescence decay kinetics at RT reveal a difference in lifetime of the main decay component: 34 +/- 1 ps for open PS I and 37 +/- 1 ps for closed PS I. At 5 K the fluorescence yield is mainly associated with long-lived components (lifetimes of 401 ps and 1.5 ns in closed PS I and of 377 ps, 1.3 ns, and 4.1 ns in samples containing approximately 50% open and 50% closed PS I). The spectra associated with energy transfer and the steady-state emission spectra suggest that the excitation energy is not completely thermally equilibrated over the core-antenna-RC complex before being trapped. Structure-based modeling indicates that the so-called red antenna pigments (A708 and A720, i.e., those with absorption maxima at 708 nm and 720 nm, respectively) play a decisive role in the observed fluorescence kinetics. The A720 are preferentially located at the periphery of the PS I core-antenna-RC complex; the A708 must essentially connect the A720 to the reaction center. The excited-state decay kinetics turn out to be neither purely trap limited nor purely transfer (to the trap) limited, but seem to be rather balanced

A new light source for multimodal multiphoton microscopy including CARS

We will present a new flexible laser source for multimodal Multiphoton excitation microscopy including CARS. It consists of a tuneable femtosecond-Ti:Sapphire laser and an optical parametric oscillator (OPO). The new OPO-design allows for high flexibility in pump- and output wavelengths giving rise to for instance image EGFP with the Ti:Sapphire and tdRFP with the OPO simultaneously. This is presented on living mouse brain tissue. The minimum energy difference between Ti:Sapphire and OPO-wavelengths achievable is 2500cm-1. Thus CARS imaging of lipids is possible. Due to synchronous pumping of the OPO the pump- and OPO pulses are intrinsically locked in time to each other thus they can be brought to perfect overlap of pump and stokes pulses. Uncaging multiphoton microscopy is also possible with this system due to the low minimum OPO pump wavelength of 730nm

Shot noise limited heterodyne detection of CARS signals

We demonstrate heterodyne detection of CARS signals using a cascaded phase-preserving chain to generate the CARS input wavelengths and a coherent local oscillator. The heterodyne ampli¯cation by the local oscillator re- veals a window for shot noise limited detection before the signal-to-noise is limited by amplitude °uctuations. We demonstrate an improvement in sensitivity by more than 3 orders of magnitude for detection using a photodiode. This will enable CARS microscopy to reveal concentrations below the current mMolar range

Invited Article: Comparison of hyperspectral coherent Raman scattering microscopies for biomedical applications

Raman scattering based imaging represents a very powerful optical tool for biomedical diagnostics. Different Raman signatures obtained by distinct tissue structures and disease induced changes provoke sophisticated analysis of the hyperspectral Raman datasets. While the analysis of linear Raman spectroscopic tissue data is quite established, the evaluation of hyperspectral nonlinear Raman data has not yet been evaluated in great detail. The two most common nonlinear Raman methods are CARS (coherent anti-Stokes Raman scattering) and SRS (stimulated Raman scattering) spectroscopy. Specifically the linear concentration dependence of SRS as compared to the quadratic dependence of CARS has fostered the application of SRS tissue imaging. Here, we applied spectral processing to hyperspectral SRS and CARS data for tissue characterization. We could demonstrate for the first time that similar cluster distributions can be obtained for multispectral CARS and SRS data but that clustering is based on different spectral features due to interference effects in CARS and the different concentration dependence of CARS and SRS. It is shown that a direct combination of CARS and SRS data does not improve the clustering results

A Psychosocial Understanding of Personality Disorder: the historical problem of Moral Insanity

Various terms such as ‘psychopath’ and ‘antisocial personality disorder’ have been used at different times to describe individuals who act, with no apparent remorse, with great callousness causing disruption and distress around them. Despite being formally described within medical texts for many years the status of these diagnoses remains highly contested both within and outside of psychiatry. It will be argued that a psychosocial perspective can firstly help us to understand why this and related categories of mental disorder have been so contentious and secondly may also point us towards more useful ways of understanding the phenomena. Two points about a psychosocial perspective are raised in this chapter. Firstly, consistent with the premise this book there is the engagement with the social and cultural significance of emotion. Secondly there is the need to cross disciplinary fissures; not only trying to bridge the most obvious gaps between the psychological and the sociological, between the individual and the cultural, but also most notably in this case the analysis benefits from historical context