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Antibunching effect is typically observed in individual systems possessing photoluminescence (PL) blinking and vice versa. Contrary to this common perception, absence of antibunching in strongly blinking methyl ammonium led tri-iodide (MAPbI3) perovskite crystals of sizes from tens to hundreds of nanometers regardless of the excitation power density is observed. Antibunching effect does not appear

This study explored factors associated with interest in taking PrEP among men who have sex with men (MSM) attending HIV testing venues in Sweden. Data from 658 HIV-negative respondents, surveyed by a questionnaire at six sites, were analyzed descriptively and by univariable and multivariable logistic regression. A total of 453 (68.8%) of the respondents expressed interest in taking PrEP. Reporting

Monolithic integration of III-V semiconductors with Silicon technology has instigated a wide range of new possibilities in the semiconductor industry, such as combination of digital circuits with optical sensing and high-frequency communication. Dissimilarities in the crystal structure symmetry and large lattice mismatch between III-V’s and Si are the challenges that prevent direct epitaxial growt

This study investigates the sex steroid hormone profile in younger men with distal radius fracture (DRF) to elucidate if this could explain the low bone density and osteoporosis previously observed. In a case–control study, 73 men with DRF (mean age 38 ± 9 years; range, 20–51) was compared with 194 age-matched, population controls. Performed assays: total testosterone (TT), calculated free testost

Nanowire (NW) arrays containing a top segment of GaxIn1–xP are investigated, comparing NWs grown using two different Ga precursors, trimethylgallium (TMGa) and triethylgallium (TEGa). TMGa is the precursor commonly used for the particle-assisted vapor–liquid–solid (VLS) growth of GaxIn1–xP NWs. However, it shows inefficient pyrolysis at typical NW growth conditions. The use of the alternative prec

Long charge carrier diffusion length and large grain size are commonly believed to be inherent properties of highly luminescent polycrystalline thin-film semiconductors. However, exactly these two properties make luminescence very susceptible to quenching by just one strongly quenching defect state if present in each grain. Moreover, when the number of quenchers per grain is small (say 1–10), it v

Attosecond pulses, produced through high-order harmonic generation in gases, have been successfully used for observing ultrafast, subfemtosecond electron dynamics in atoms, molecules and solid state systems. Today's typical attosecond sources, however, are often impaired by their low repetition rate and the resulting insufficient statistics, especially when the number of detectable events per shot

Tunnel field-effect transistors (TFETs) are promising candidates that have demonstrated potential for and beyond the 3 nm technology node. One major challenge for the TFETs is to optimize the heterojunction for high drive currents while achieving steep switching. Thus far, such optimization has mainly been addressed theoretically. Here, we experimentally investigate the influence of the source seg

Adiabatic elimination methods allow the reduction of the space dimension needed to describe systems whose dynamics exhibit separation of timescale. For open quantum systems, it consists in eliminating the fast part assuming it has almost instantaneously reached its steady state and obtaining an approximation of the evolution of the slow part. These methods can be applied to eliminate a linear subs

Electronic 2D spectroscopy allows nontrivial quantum effects to be explored in unprecedented detail. Here, we apply recently developed fluorescence detected coherent 2D spectroscopy to study the light harvesting antenna 2 (LH2) of photosynthetic purple bacteria. We report double quantum coherence 2D spectra which show clear cross peaks indicating correlated excitations. Similar results are found f

We investigated the excited-state dynamics of CH3NH3PbBr3 perovskite nanoparticles (NPs) and bulk crystals under various excitation intensity regimes using transient absorption spectroscopy. We confirmed the sub-band gap hole trap states with optical transition to the conduction band in both samples. In bulk crystals, the excited-state dynamics is independent of pump intensity. However, in NPs, pr

Mn-doping into CdS quantum dots (QDs) has been demonstrated a useful way to enhance the power conversion efficiency (PCE) of quantum dot sensitized solar cells (QDSCs), the detailed systematic study is needed to get a better fundamental understanding. This work focuses on the study of the effects of Mn dopant on light harvesting, charge transfer, and charge collection of the solar cells. The resul

Crustacean copepods in high-latitude lakes frequently alter their pigmentation facultatively to defend themselves against prevailing threats, such as solar ultraviolet radiation (UVR) and visually oriented predators. Strong seasonality in those environments promotes phenotypic plasticity. To date, no one has investigated whether low-latitude copepods, experiencing continuous stress from UVR and pr

OBJECTIVES: Infections with extended spectrum beta-lactamase (ESBL) producing Enterobacteriaceae (EPE) are a major healthcare concern. Our goal was to investigate whether a probiotic mixture could be used for eradication therapy in patients with prolonged intestinal EPE carriage.METHODS: We performed a randomized, placebo-controlled single blinded clinical superiority trial in the south of Sweden

Background and objective: Involvement of pulmonary vascular remodelling is a characteristic sign in COPD. Vascular mediators such as vascular endothelial growth factor (VEGF) and prostacyclin may regulate fibroblast activity. The objective was to study the synthesis of VEGF and interactions with prostacyclin and transforming growth factor (TGF)-β1 in lung fibroblasts from patients with COPD and he

Ultrafast processes in matter can be captured and even controlled by using sequences of few-cycle optical pulses, which need to be well characterized, both in amplitude and phase. The same degree of control has not yet been achieved for few-cycle extreme ultraviolet pulses generated by high-order harmonic generation (HHG) in gases, with duration in the attosecond range. Here, we show that by varyi