The BICEP/
Keck
series of experiments target the cosmic microwave background at degree-scale resolution from the South Pole. Over the next few years, the “Stage-3” BICEP Array (BA) telescope will ...improve the program’s frequency coverage and sensitivity to primordial B-mode polarization by an order of magnitude. The first receiver in the array, BA1, began observing at 30/40 GHz in early 2020. The next two receivers, BA2 and BA3, are currently being assembled and will map the southern sky at frequencies ranging from 95 to 150 GHz. Common to all BA receivers is a refractive, on-axis, cryogenic optical design that focuses microwave radiation onto a focal plane populated with antenna-coupled bolometers. High-performance antireflective coatings up to 760 mm in aperture are needed for each element in the optical chain, and must withstand repeated thermal cycles down to 4 K. Here, we present the design and fabrication of the 30/40 GHz anti-reflection coatings for the recently deployed BA1 receiver, with indices matched to its various polyethylene, nylon and alumina optical components. We describe an epoxy coating technique designed for alumina optics, which achieves better than 80% transmission at room temperature. For polyethylene optical elements, we present a new heat-compression approach that allows low-density polytetrafluoroethylene AR layers to reach sub-percent reflected power. We describe the planned use of these methods for the next BA cryostats, which may inform technological choices for future small-aperture telescopes of the CMB-S4 experiment.
Levetiracetam (LEV), a novel anti-epileptic drug that has been demonstrated with an anti-inflammatory effect, but the exact mechanisms of its action remain to be fully defined. The present study ...aimed to evaluate the possible effects of LEV on lipopolysaccharides (LPS)-induced Janus kinase-signal transducers and activators of transcription (JAK/STAT) as well as toll-like receptor 4 (TLR4)/ mitogen activated protein kinase (MAPK) signaling pathways activation in adjuvant induced arthritis (AIA). Rats were allocated into normal control, three arthritic control groups: Complete Freund's Adjuvant (CFA) (0.4 ml/3days/12days), LPS (100 µg/kg/day), CFA+LPS, and three treated groups: CFA+LEV, LPS+LEV and CFA+LPS+LEV. LEV was administered in a dose 50 mg/kg/day for 15 day. After 28 days, tissue samples were collected for assessment of phosphorylated JAK2, STAT3, TLR4, MAPK and cathepsin K quantitative expression in synovium. Additionally, Serum samples were used for biochemical evaluation of interleukin-6 (IL-6), interleukin-1beta (IL-1B), LPS, anti-citrullinated protein antibody (ACPA) and 8-hydroxydeoxyguanosine (8-OHdG). Histopathological and macroscopical examinations of joints were also performed to support our study. Results indicated that LEV exerted its anti-inflammatory effect through inhibiting LPS-dependent phosphorylation of JAK2/STAT3 signaling. It significantly suppressed TLR4 and MAPK expressions, thereby decreasing release of inflammatory cytokines IL-1β, IL-6.LEV exhibited a potent inhibitory effect on cathepsin K and 8-OHdG parallel to confirmatory histopathological and macroscopical findings. In conclusion, LEV has a powerful therapeutic effect on adjuvant induced arthritis in rats and its mechanisms are strongly related to inhibiting excessive activation of JAK2-STAT3 and TLR4 pathways. This may add a new approach for treatment of RA.
The BICEP/$\textit{Keck}$ (BK) series of cosmic microwave background (CMB)
polarization experiments has, over the past decade and a half, produced a
series of field-leading constraints on cosmic ...inflation via measurements of the
"B-mode" polarization of the CMB. Primordial B modes are directly tied to the
amplitude of primordial gravitational waves (PGW), their strength parameterized
by the tensor-to-scalar ratio, $r$, and thus the energy scale of inflation.
Having set the most sensitive constraints to-date on $r$, $\sigma(r)=0.009$
($r_{0.05}<0.036, 95\%$ C.L.) using data through the 2018 observing season
(``BK18''), the BICEP/$\textit{Keck}$ program has continued to improve its
dataset in the years since. We give a brief overview of the BK program and the
"BK18" result before discussing the program's ongoing efforts, including the
deployment and performance of the $\textit{Keck Array}$'s successor instrument,
BICEP Array, improvements to data processing and internal consistency testing,
new techniques such as delensing, and how those will ultimately serve to allow
BK reach $\sigma(r) \lesssim 0.003$ using data through the 2027 observing
season.
Multifocal atrial tachycardia (MAT) was observed in 9 patients aged 60-85 (mean 72.1±8.6) years during exacerbation of their chronic lung and/or cardiac disease. Four, in whom the rapid heart rate ...caused symptoms of pulmonary congestion, were treated with intravenous amiodarone (450-900mg over 2 hours) with restoration of sinus rhythm soon after the termination of the drug infusion. In 1, with recurrence of MAT, the same intravenous dosage was repeated for 2 consecutive days, with final achievement of stable sinus rhythm. Five patients, apart from the conventional management of their underlying disease (digitalis, diuretics, aminophylline) were treated with oral amiodarone (600mg/day). Sinus rhythm was restored in all and remained stable during their hospitalization, under α maintenance dosage of 200-400mg daily. Amiodarone may be the drug of choice for the treatment of MAT, for which up to now no effective therapy has been established.
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