Thin layers of silicon nanocrystals (SiNC) in oxide matrix with optimized parameters are fabricated by the plasma-enhanced chemical vapor deposition. These materials with SiNC sizes of about 4.5 nm ...and the SiO
barrier thickness of 3 nm reveal external quantum yield (QY) close to 50% which is near to the best chemically synthetized colloidal SiNC. Internal QY is determined using the Purcell effect, i.e. modifying radiative decay rate by the proximity of a high index medium in a special wedge-shape sample. For the first time we performed these experiments at variable temperatures. The complete optical characterization and knowledge of both internal and external QY allow to estimate the spectral distribution of the dark and bright NC populations within the SiNC ensemble. We show that SiNCs emitting at around 1.2-1.3 eV are mostly bright with internal QY reaching 80% at room temperature and being reduced by thermally activated non-radiative processes (below 100 K internal QY approaches 100%). The mechanisms of non-radiative decay are discussed based on their temperature dependence.
The broad-band SEDs of blazars exhibit two broad spectral components, which in leptonic emission models are attributed to synchrotron radiation and synchrotron self-Compton (SSC) radiation of ...relativistic electrons. During high-state phases, the high-frequency SSC component often dominates the low-frequency synchrotron component, implying that the inverse-Compton SSC losses of electrons are at least equal to or greater than the synchrotron losses of electrons. We calculate from the analytical solution of the kinetic equation of relativistic electrons, subject to the combined linear synchrotron and non-linear SSC cooling, for monoenergetic injection the time-integrated total synchrotron and SSC radiation fluences and spectral energy distributions (SEDs). Depending on the ratio of the initial cooling terms, displayed by the injection parameter α, we find for α≪ 1, implying complete linear cooling, that the synchrotron peak dominates the inverse-Compton peak and the usual results of the spectra are recovered. For α≫ 1, the SSC peak dominates the synchrotron peak, proving our assumption that in such a case the cooling becomes initially non-linear. The spectra also show some unique features, which can be attributed directly to the non-linear cooling. To show the potential of the model, we apply it to outbursts of 3C 279 and 3C 454.3, successfully reproducing the SEDs. The results of our analysis are promising, and we argue that this non-equilibrium model should be considered in future modelling attempts for blazar flares.
Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material ...slams into the companion star's wind can accelerate particles. We report very-high-energy (VHE; Formula: see text) gamma rays from the recurrent nova RS Ophiuchi, up to 1 month after its 2021 outburst, observed using the High Energy Stereoscopic System (H.E.S.S.). The temporal profile of VHE emission is similar to that of lower-energy giga-electron volt emission, indicating a common origin, with a 2-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic rays to very high energies.
Background. Targets for peritoneal dialysis (PD) utilization may be difficult to achieve because many older patients have contraindications to PD or barriers to self-care. The objectives of this ...study were to determine the impact that contraindications and barriers to self-care have on incident PD use, and to determine whether family support increased PD utilization when home care support is available. Methods. Consecutive incident dialysis patients were assessed for PD eligibility, offered PD if eligible and followed up for PD use. All patients lived in regions where home care assistance was available. Results. The average patient age was 66 years. One hundred and ten (22%) of the 497 patients had absolute medical or social contraindications to PD. Of the remaining 387 patients who were potentially eligible for PD, 245 (63%) had at least one physical or cognitive barrier to self-care PD. Patients with barriers were older, weighed less and were more likely to be female, start dialysis as an inpatient and have a history of vascular disease, cardiac disease and cancer. Family support was associated with an increase in PD eligibility from 63% to 80% (P = 0.003) and PD choice from 40% to 57% (P = 0.03) in patients with barriers to self-care. Family support increased incidence PD utilization from 23% to 39% among patients with barriers to self-care (P = 0.009). When family support was available, 34% received family-assisted PD, 47% received home care-assisted PD, 12% received both family- and home care-assisted PD, and 7% performed only self-care PD. Incident PD use in an incident end-stage renal disease (ESRD) population was 30% (147 of the 497 patients). Conclusions. Contraindications, barriers to self-care and the availability of family support are important drivers of PD utilization in the incident ESRD population even when home assistance is available. These factors should be considered when setting targets for PD.
The blazar Mrk 501 (z = 0.034) was observed at very-high-energy (VHE, E 100 GeV) gamma-ray wavelengths during a bright flare on the night of 2014 June 23-24 (MJD 56832) with the H.E.S.S. phase-II ...array of Cherenkov telescopes. Data taken that night by H.E.S.S. at large zenith angle reveal an exceptional number of gamma-ray photons at multi-TeV energies, with rapid flux variability and an energy coverage extending significantly up to 20 TeV. This data set is used to constrain Lorentz invariance violation (LIV) using two independent channels: a temporal approach considers the possibility of an energy dependence in the arrival time of gamma-rays, whereas a spectral approach considers the possibility of modifications to the interaction of VHE gamma-rays with extragalactic background light (EBL) photons. The non-detection of energy-dependent time delays and the non-observation of deviations between the measured spectrum and that of a supposed power-law intrinsic spectrum with standard EBL attenuation are used independently to derive strong constraints on the energy scale of LIV (EQG) in the subluminal scenario for linear and quadratic perturbations in the dispersion relation of photons. For the case of linear perturbations, the 95% confidence level limits obtained are EQG,1 > 3.6 × 1017 GeV using the temporal approach and EQG,1 > 2.6 × 1019 GeV using the spectral approach. For the case of quadratic perturbations, the limits obtained are EQG,2 > 8.5 × 1010 GeV using the temporal approach and EQG,2 > 7.8 × 1011 GeV using the spectral approach.
Penile Squamous Cell Carcinoma (PSCC) is associated with high-risk human papillomavirus (HR-HPV). The immunohistochemical (IHC) test for p16
(p16) is highly correlated with HR-HPV expression in other ...SCCs. To investigate whether the expression of p16 IHC or HR-HPV is associated with survival in PSCC, we conducted a single institution analysis of 143 patients with a diagnosis of PSCC and, available tissue were tested for p16 IHC staining patterns, histological subtype, tumor grade, and lymphovascular invasion (LVI) by an experienced pathologist. HR-HPV status using the Cobas PCR Assay or the RNAScope high-risk HPV in situ hybridization kit were also assessed. Patient characteristics were summarized using descriptive statistics of clinico-pathologic variables. Kaplan-Meier was used to estimate median overall survival (OS), cancer specific survival (CSS) and correlated with HPV, p16, and other study variables. Patients with p16+ tumors had a significantly longer median CSS in comparison to the p16- group (
= 0.004), with respective 5-year CSS probability of 88% (95% CI; 0.84, 1) versus 58% (95% CI; 0.55, 0.76;
= 0.004). HPV status did not predict survival outcomes. Multivariable analysis with respect to OS and CSS, showed that p16+ status was associated with a lower risk of death (HR = 0.36, 95%CI; 0.20-0.67,
= 0.001), and improved CSS (HR = 0.20, 95% CI; 0.07-0.54,
= 0.002) after adjusting for covariates. In conclusion, tumor p16 status via IHC was an easy to perform independent prognostic factor for OS and CSS that correlates with HR-HPV expression.
The aim of this study was to perform the physical and physiological quality analysis of intermittent soybean seeds drying in the spouted bed. Mechanical damages and physiological properties were ...evaluated by tests of germination, first germination count, seedling length, tetrazolium, sodium hypochlorite, and X-ray. Five different intermittency profiles and two different intermittency methodologies with periodic reduction and interruption of the air flow were employed. Continuous and intermittent processes with shorter periods of reduced air flow (A.1) provided a lower degree of seed deterioration, considering both physiological and physical aspects. The findings of this study contributed to identify the distinct trend of intermittency application in the spouted bed in relation to other dryers when seed quality attributes are demanded, highlighting as a promising field for further studies.
Patients on dialysis are often elderly and frail, with multiple comorbid conditions, and are heavy users of Emergency Department (ED) services. However, objective data on the frequency and pattern of ...ED utilization by dialysis patients are sparse. Such data could identify periods of highest risk for ED visits and inform health systems interventions to mitigate these risks and improve outcomes.
To describe the pattern and frequency of presentation to ER by dialysis patients.
Retrospective cohort study using administrative data collected over ten years (2000-2009) in the Province of Manitoba, Canada.
Patients presenting to any of 9 ED's in Winnipeg and Brandon Manitoba. These departments serve >90% of the population of Manitoba, Canada (population 1.2 million).
All patients presenting to an ED in any of 9 emergency departments in Manitoba, Canada.
Dialysis status.
Presentation to the ED.
Over 2.1 million ED visits by more than 1.2 million non-dialysis patients and 17,782 ED visits by 3257 dialysis patients were included. Dialysis patients presented 8.5 times more frequently to the ED than the general population (age and sex adjusted, p<0.001). For dialysis patients, ED utilization was significantly higher following the long interdialytic interval (33.6% higher Mondays and 19.5% higher Tuesdays vs. other days of the week, p<0.001) and was 10-fold higher in the 7 days before and after the initiation of dialysis.
The heavy use of ED services by dialysis patients spikes upward following the long interdialytic interval and also in the week before and after dialysis initiation. The relative risks associated with these vulnerable periods were much higher than those reported for clinical patient characteristics. We propose that intrinsic gaps in the structure of care delivery (e.g. 3 times a week dialysis, imperfect surveillance and clinical monitoring of patients with low GFR) may be the fundamental drivers of this periodicity. Strategies to mitigate this excess health risk are needed.
Long noncoding RNAs (lncRNAs) significantly influence the development and regulation of genome expression in cells. Here, we demonstrate the role of lncRNA ceruloplasmin (NRCP) in cancer metabolism ...and elucidate functional effects leading to increased tumor progression. NRCP was highly upregulated in ovarian tumors, and knockdown of NRCP resulted in significantly increased apoptosis, decreased cell proliferation, and decreased glycolysis compared with control cancer cells. In an orthotopic mouse model of ovarian cancer, siNRCP delivered via a liposomal carrier significantly reduced tumor growth compared with control treatment. We identified NRCP as an intermediate binding partner between STAT1 and RNA polymerase II, leading to increased expression of downstream target genes such as glucose-6-phosphate isomerase. Collectively, we report a previously unrecognized role of the lncRNA NRCP in modulating cancer metabolism. As demonstrated, DOPC nanoparticle-incorporated siRNA-mediated silencing of this lncRNA in vivo provides therapeutic avenue toward modulating lncRNAs in cancer.
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•Long noncoding RNA NRCP is upregulated in ovarian cancer•NRCP promotes cancer cell progression by promoting glycolysis•Silencing NRCP results in apoptosis and decreased tumor progression
The lncRNA NRCP is upregulated in ovarian cancer. Rupaimoole et al. show that NRCP is involved in cancer cell glycolysis and promotes tumor growth and proliferation. They find that silencing NRCP using DOPC-siRNAs in vivo results in robust anti-tumor effects.
Gamma-ray line signatures can be expected in the very-high-energy (E(γ)>100 GeV) domain due to self-annihilation or decay of dark matter (DM) particles in space. Such a signal would be readily ...distinguishable from astrophysical γ-ray sources that in most cases produce continuous spectra that span over several orders of magnitude in energy. Using data collected with the H.E.S.S. γ-ray instrument, upper limits on linelike emission are obtained in the energy range between ∼ 500 GeV and ∼ 25 TeV for the central part of the Milky Way halo and for extragalactic observations, complementing recent limits obtained with the Fermi-LAT instrument at lower energies. No statistically significant signal could be found. For monochromatic γ-ray line emission, flux limits of (2 × 10(-7) -2 × 10(-5)) m(-2) s(-1) sr(-1) and (1 × 10(-8) -2 × 10(-6)) m(-2) s(-1)sr(-1) are obtained for the central part of the Milky Way halo and extragalactic observations, respectively. For a DM particle mass of 1 TeV, limits on the velocity-averaged DM annihilation cross section ⟨σv⟩(χχ → γγ) reach ∼ 10(-27) cm(3)s(-1), based on the Einasto parametrization of the Galactic DM halo density profile.
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