Transition Correlation Studies In A Water Vapour Laser

The interaction between several pairs of coupled water vapour lines was investigated with a compound mirror-grating-grating (MGG) laser, which allows the simultaneous and coaxial lasing of two linearly polarized wavelengths parallel or perpendicular to each other.;The interaction experiments were done with four pairs of competitive water vapour lines; the 26.6 and 47.70, 26.6 and 47.47, 27.97 and 47.70, and 27.97 and 47.47 micrometer lines. The coupled lines share an upper or lower energy level.;From the experimental results of 26.6 and 47.70 micrometer lines, the parallel polarized line coupling constant was 0.18 {dollar}\pm{dollar} 0.04, and the perpendicular constant was 0.54 {dollar}\pm{dollar} 0.06. The ratio of the two coupling constants, which is a ratio of the competition between the two lines for magnetic sub-level population of the shared level, was equal to 0.40 {dollar}\pm{dollar} 0.14 which compares well with the theoretical value of 0.35.;Although the experimental results of the three other pairs of lines did not allow coupling constants to be calculated, the power suppression of the longer wavelengths demonstrated that the lines were coupled, and that the coupling depended on the relative polarization of the lines: the 47.70 micrometer line was completely suppressed whenever the 27.97 micrometer line lased.;The single line two perpendicular polarization mode control features of a compound mirror-grating-mirror (MGM) laser were also investigated: the output can be in one or the other or both modes. The resonator\u27s polarization properties are due in part to the different effective phase change upon reflection from the resonator\u27s grating for radiation parallel and perpendicular to the grating lines. This can be expressed as a difference in the effective optical plane positions for the two polarizations. From the simultaneous measurement of the modes with the displacement of the resonator mirrors, the optical plane difference was measured to be 17 {dollar}\pm{dollar} 1 micrometers for the 30 micrometer blazed grating used. The ratio of the optical plane difference to the groove depth of the grating was 0.32 {dollar}\pm{dollar} 0.02, in fair agreement with the theoretical calculated value of 0.21

Quetiapine modulates anxiety-like behaviours and alleviates the decrease of BDNF in the amygdala of an APP/PS1 transgenic mouse model of Alzheimer’s disease

Quetiapine, an atypical antipsychotic drug, is effective in treating the behavioural and the psychological symptoms of dementia (BPSD). The objective of this study was to examine the effects of quetiapine on anxiety-like behaviour in the amyloid precursor protein (APP)/ presenilin 1 (PS1) double transgenic mouse model of Alzheimer’s disease (AD). The mice were treated with quetiapine (0, 2.5, or 5 mg/kg/day) orally in drinking water for 7 or 10 months starting from 2 months of age. Conditioned anxiety was measured using the elevated T-maze (ETM). To measure memory, the Y-maze and the Morris Water maze were employed. After behavioural testing, â-amyloid (Aâ) plaques in the hippocampus and cortex of transgenic mice were stained using Congo Red. Brain-derived neurotrophic factor (BDNF) in the basolateral amygdala (BLA) and the hippocampus of mice was examined using immunohistochemical methods. The statistics revealed an interaction between quetiapine and APP/PS1 double transgenic mice in the avoidance phase of the ETM. Quetiapine modulates anxiety-like behaviours in the ETM. The anxiety-like behaviours were associated with reductions in BDNF levels in the BLA and hippocampus of the transgenic mice. This was reversed by treatment with quetiapine. Furthermore, chronic administration of quetiapine attenuated the memory impairment and decreased the Aâ plaque load in the brain. This study demonstrates that quetiapine normalizes anxiety-like behaviour and up-regulates cerebral BDNF levels in the APP/PS1 mice, suggesting that quetiapine may function as a neuroprotectant as well as an antipsychotic in treating the BPSD associated with AD

TOWARDS A THEORY ON THE CAUSES OF THE GREEK DEPRESSION: An Investigation of National Balance Sheet Data (1997-2014). CES Open Forum Series 2018-2019

Drawing on a new dataset, I explore the dynamics of national wealth accumulation in Greece since 1997, and suggest a thought-provoking narrative on the causes of the Greek depression. I show that about two-thirds of the increase in external public debt during the pre-crisis period inside the euro area can be attributed to factors other than fiscal indiscipline. A positive wealth effect tied to the housing bubble resulted in a low level of national saving, thereby pushing the government to borrow from abroad to roll over its debt issued domestically and to finance investment in capital goods. Compared to Spain and Ireland, two explanations may account for the rise in external public - instead of corporate - debt during the pre-crisis period: (i) the smaller size of firms that were relatively more credit-constrained and thus had limited access to external financing, and (ii) the larger initial size of the government balance sheet - in terms of both assets and liabilities - that generated a greater incentive to roll over existing domestic debt and invest in physical assets through external borrowings

Buoyancy-driven exchange flows in inclined ducts

Buoyancy-driven exchange flows arise in the natural and built environment wherever bodies of fluids at different densities are connected by a narrow constriction. In this paper we study these flows in the laboratory using the canonical stratified inclined duct experiment, which sustains an exchange flow in an inclined duct of rectangular cross-section over long time periods (Meyer & Linden, J. Fluid Mech., vol. 753, 2014, pp. 242–253). We study the behaviour of these sustained stratified shear flows by focusing on three dependent variables of particular interest: the qualitative flow regime (laminar, wavy, intermittently turbulent or fully turbulent), the mass flux (net transport of buoyancy between reservoirs) and the interfacial thickness (thickness of the layer of intermediate density between the two counter-flowing layers)

Who Pays for Sustainability? An Analysis of Sustainability-Linked Bonds

We examine the novel phenomenon of sustainability-linked bonds (SLBs). These bonds’ coupon is linked to the issuer achieving a predetermined sustainability performance target. We estimate the yield differential between SLBs and non-sustainable counterfactuals by matching bonds from the same issuer. Our results show that in most cases investors pay for the improvement in sustainability, while issuers benefit from a sustainability premium. Our analysis suggests that the sustainability premium is larger for bonds with a higher coupon step-up and for callable bonds. We also show that there is a ‘free lunch’ for some SLB issuers, as their financial savings are higher than the potential penalty, and they have a call option to reduce this penalty. While our findings suggest that most SLBs incentivize sustainability improvements by offering a lower cost of capital, some companies that do not benefit from a sustainability premium seem to issue SLBs to signal their commitment to sustainability targets. The ‘free lunch’ however suggests that SLBs can also be a form of greenwashing, when they are issued purely for financial optimization without a real commitment to carry out sustainability improvements

Cell detachment and label-free cell sorting using modulated surface acoustic waves (SAW) in droplet-based microfluidics

We present a droplet-based surface acoustic wave (SAW) system designed to viably detach biological cells from a surface and sort cell types based on differences in adhesion strength (adhesion contrast), without the need to label cells with molecular markers. The system uses modulated SAW to generate pulsatile flows in the droplets and efficiently detach the cells, thereby minimizing SAW excitation power and exposure time. As a proof-of-principle, the system is shown to efficiently sort HEK 293 from A7r5 cells based on adhesion contrast. Results are obtained in minutes with sorting purity and efficiency reaching 97 % and 95 %, respectively.Comment: Accepted for publication in Lab on a Chi

Robust Coherent Control of Bimolecular Collisions beyond the Ultracold Regime

Quantum coherent control of bimolecular collisions beyond the ultracold regime can face a major challenge due to the incoherent addition of different partial wave contributions to the total scattering cross section. These contributions become increasingly numerous as the collision energy increases, leading to a loss of overall control. Here, we overcome this limitation by leveraging the recently discovered Partial Wave Phase Locking (PWPL) effect, which synchronizes the oscillations of all partial wave contributions. By using rigorous quantum scattering calculations, we demonstrate that PWPL enables coherent control of spin exchange in ion-atom collisions, far outside the ultracold regime, even with as many as 5000 partial wave contributions. The predicted extent of control is sufficient to be measurable in cold atom-ion hybrid experiments