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Visible Light Communication (VLC) is a breakthrough technology, enabling a new type of wireless communications in both indoor and outdoor. For the first time, here we achieve VLC transmission in indoor by combining a new and innovative, large-Field of View (FoV) receiver with commercial high-power white Light Emitting Diodes (LEDs). After careful characterization and optimization of the devices, we assess the system performance by Bit Error Ratio (BER) measurements. Then, in a realistic configuration, we perform several transmission tests. We transmit a real-time 10 Mbit/s HD video stream. Finally, mixed-color white LEDs are also shown to be instrumental in improving the performance. Our work paves the way to the deployment of the proposed solution in real scenarios.

The cylindrical drift chamber is the most innovative part of the MEG II detector, the upgraded version of the MEG experiment. The MEG II chamber differs from the MEG one because it is a single volume cylindrical structure, instead of a segmented one, chosen to improve its resolutions and efficiency in detecting low energy positrons from muon decays at rest. In this paper, we show the characteristics and performances of this fundamental part of the MEG II apparatus and we discuss the impact of its higher resolution and efficiency on the sensitivity of the MEG II experiment. Because of its innovative structure and high quality resolution and efficiency the MEG II cylindrical drift chamber will be a cornerstone in the development of an ideal tracking detector for future positron-electron collider machines.

The MEG II experiment, located at the Paul Scherrer Institut (PSI) in Switzerland, is the successor to the MEG experiment, which completed data taking in 2013. MEG II started fully operational data taking in 2021, with the goal of improving the sensitivity of the μ + → e + γ decay down to ∼ 6 × 10 - 14 almost an order of magnitude better than the current limit. In this paper, we describe the operation and performance of the experiment and give a new estimate of its sensitivity versus data acquisition time.

The atmospheric Cherenkov gamma-ray telescope MAGIC, designed for a low-energy threshold, has detected very-high-energy gamma rays from a giant flare of the distant Quasi-Stellar Radio Source (in short: radio quasar) 3C 279, at a distance of more than 5 billion light-years (a redshift of 0.536). No quasar has been observed previously in very-high-energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high-energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts.

We present the first direct search for lepton flavour violating muon decay mediated by a new light particle X, μ + → e + X , X → γ γ . This search uses a dataset resulting from 7.5 × 10 14 stopped muons collected by the MEG experiment at the Paul Scherrer Institut in the period 2009–2013. No significant excess is found in the mass region 20–45 MeV/c 2 for lifetimes below 40 ps, and we set the most stringent branching ratio upper limits in the mass region of 20–40 MeV/c 2 , down to O ( 10 - 11 ) at 90% confidence level.

Microquasars are binary star systems with relativistic radio-emitting jets. They are potential sources of cosmic rays and can be used to elucidate the physics of relativistic jets. We report the detection of variable gamma-ray emission above 100 gigaelectron volts from the microquasar LS I 61 + 303. Six orbital cycles were recorded. Several detections occur at a similar orbital phase, which suggests that the emission is periodic. The strongest gamma-ray emission is not observed when the two stars are closest to one another, implying a strong orbital modulation of the emission or absorption processes.

IntroductionRecurrence of angina after percutaneous coronary intervention (PCI) affects 20–35% of patients with stable coronary artery disease. Few data are available in the setting of ST-segment elevation myocardial infarction (STEMI) treated with primary PCI and pathogenic mechanisms are largely unknown. In this study, we evaluated the relation between coronary microvascular obstruction (MVO) and recurrence of angina at follow-up.MethodsWe prospectively enrolled patients with STEMI undergoing primary PCI. MVO was defined as TIMI flow <3 or TIMI flow 3 with myocardial blush grade <2. The primary endpoints were recurrence ofangina at follow-up and angina status evaluated by Seattle Angina Questionnaire Summary Score (SAQSS). Therapy at follow-up and occurrence of major adverse cardiovascular events (MACE), defined as the composite of cardiac death, non-fatal myocardial infarction (MI) and target vessel revascularization (TVR), were also collected.ResultsWe enrolled 200 patients (66.5±11.3 years, male 75.5%). MVO occurred in 52 (26.1%) of them. Follow-up (mean time 25.17±9.28 months) was performed in all patients. Recurrent angina occurredin 29 (17.1%) patients, with a higher prevalence in patients with MVO compared with patients without MVO [11 (28.9%) vs 18 (10.6%); p=0.047]. Accordingly, SAQSS was lower in patients with MVO compared with patients without MVO, and the need of ≥2 antianginal drugs was higher in patients with MVO. Of note, at multiple linear regression analysis history of previous acute coronary syndrome and occurrence of MVO were the only independent predictors of a worse SAQSS (R2=0.089, p=0.001). Finally, occurrence of MACE [17 (32.7%) vs 25 (17%), p=0.028] was higher in patients with MVO compared with patients without MVO.ConclusionRecurrence of angina in STEMI patients treated with primary PCI is an important clinical issue. Occurrence of MVO portends a worse angina status and is associated with the use of more antianginal drugs.Conflict of InterestNo conflict of interest

Obesity-related hypertension is associated with increased activity of the renin-angiotensin-aldosterone system (RAAS), increasing arterial stiffness. Aerobic exercise decreases pulse wave velocity (PWV), therefore a treatment option for hypertension and obesity. Assess RAAS activity and PWV before and after 4 weeks of aerobic training in unmedicated, pre-to-stage-1 hypertensives. Ten obese subjects (52±3.2 years, body mass index=33.5±1.4) performed 30 min of aerobic exercise on a treadmill 3 days per week at 65% of peak oxygen consumption (VO 2peak ). Descriptive characteristics, systolic and diastolic blood pressure (SBP and DBP), PWV, and a blood draw was performed at baseline, following the 4-week control and training interventions. No differences in descriptive characteristics during the control period were observed, however, a significant decrease in plasma aldosterone (ALDO) (255.4±75 to 215.8±66 pg ml −1 , P =0.001), SBP (140±12 to 136±10.4 mm Hg; P =0.02), DBP (89±4.2 to 85±6.3 mm Hg; P =0.03) and central PWV (11.2±0.6 to 9.8±0.8 m s −1 ; P =0.04) was shown pre-to-post exercise training. Four weeks of moderate-intensity aerobic training in obese, hypertensives decreases plasma ALDO independently of body weight and is significantly correlated to decreases in PWV reductions.

Obesity-related hypertension is associated with increased activity of the renin-angiotensin-aldosterone system (RAAS), increasing arterial stiffness. Aerobic exercise decreases pulse wave velocity (PWV), therefore a treatment option for hypertension and obesity. Assess RAAS activity and PWV before and after 4 weeks of aerobic training in unmedicated, pre-to-stage-1 hypertensives. Ten obese subjects (52 ± 3.2 years, body mass index = 33.5 ± 1.4) performed 30 min of aerobic exercise on a treadmill 3 days per week at 65% of peak oxygen consumption (V[O.sub.2peak]). Descriptive characteristics, systolic and diastolic blood pressure (SBP and DBP), PWV, and a blood draw was performed at baseline, following the 4-week control and training interventions. No differences in descriptive characteristics during the control period were observed, however, a significant decrease in plasma aldosterone (ALDO) (255.4 ± 75 to 215.8 ± 66 pg ml_ 1, P = 0.001), SBP (140 ± 12 to 136 ± 10.4 mm Hg; P = 0.02), DBP (89 ± 4.2 to 85 ± 6.3 mm Hg; P = 0.03) and central PWV (11.2 [+ or -] 0.6 to 9.8 ± 0.8 m [s.sup.-1]; P = 0.04) was shown pre-to-post exercise training. Four weeks of moderate-intensity aerobic training in obese, hypertensives decreases plasma ALDO independently of body weight and is significantly correlated to decreases in PWV reductions. Journal of Human Hypertension (2015) 29, 53-57; doi: 10.1038/jhh.2014.33; published online 1 May 2014

The observation of a resonance structure in the opening angle of the electron-positron pairs in the$$^{7}$$7 Li(p,e$$^+$$+ e$$^-$$- )$$^{8}$$8 Be reaction was claimed and interpreted as the production and subsequent decay of a hypothetical particle (X17). Similar excesses, consistent with this particle, were later observed in processes involving$$^{4}$$4 He and$$^{12}$$12 C nuclei with the same experimental technique. The MEG II apparatus at PSI, designed to search for the$$\\mu ^+ \\rightarrow \\textrm{e}^+ \\gamma $$μ + → e + γ decay, can be exploited to investigate the existence of this particle and study its nature. Protons from a Cockroft–Walton accelerator, with an energy up to 1.1 MeV, were delivered on a dedicated Li-based target. The$$\\gamma $$γ and the e$$^{+}$$+ e$$^{-}$$- pair emerging from the$$^8\\textrm{Be}^*$$8 Be ∗ transitions were studied with calorimeters and a spectrometer, featuring a broader angular acceptance than previous experiments. We present in this paper the analysis of a four-week data-taking in 2023 with a beam energy of 1080 keV, resulting in the excitation of two different resonances with Q-value 17.6 and 18.1 MeV. No significant signal was found, and limits at 90% C.L. on the branching ratios (relative to the$$\\gamma $$γ emission) of the two resonances to X17 were set,$$R_{17.6} <{1.8}\\,\\times \\,10^{-6}$$R 17.6 < 1.8 × 10 - 6 and$$R_{18.1} < {1.2}\\,\\times \\,10^{-5}$$R 18.1 < 1.2 × 10 - 5 in the mass range between$${16.5}\\hbox { MeV}/\\hbox {c}^{2}$$16.5 MeV / c 2 and$${17.1}\\hbox { MeV}/\\hbox {c}^{2}$$17.1 MeV / c 2 .