We present the protection system for the monitoring circuitry of the 20 kV high-voltage bias for the Hybrid Photon Detectors of the Ring Imaging Cherenkov detectors of the LHCb experiment. The ...protection system buffers the voltage lines, attenuated by about 12700 V/V in normal operating conditions, and limits the output voltage excursion to the ADCs of the monitoring system to a safe range (between -2.5 V and +5 V) in case of discharge. The circuit has been designed and tested to be radiation tolerant under the expected working conditions of LHCb. Results show that the protection boards are fully adequate for the whole LHCb lifetime.
The utility of neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) as prognostic markers in Feline Leukemia Virus (FeLV) and Feline ...Immunodeficiency Virus (FIV) infections has not yet been investigated. The aim of this study was to investigate these leukocyte ratios in retrovirus-positive cats and to evaluate their prognostic value for survival. This retrospective case-control study included 142 cats, 75 FIV-Antibodies (Ab)-positive, 52 FeLV-Antigen (Ag)-positive, and 15 FIV-Ab+FeLV-Ag-positive, and a control population of 142 retrovirus-negative age-, sex-, and lifestyle-matched cats. Signalment, complete blood count at the time of serological testing, and outcome were recorded. Leukocyte ratios were compared within the same case-control population, among the three retrovirus-seropositive populations, and were related to survival time. No significant difference was found in NLR, MLR, or PLR between FIV-Ab-positive and FIV-Ab+FeLV-Ag-positive cats and their cross-matched controls. In the FeLV-Ag-positive population, MLR was significantly lower than in the control population (0.05 and 0.14, respectively, P=0.0008). No ratio discriminated among the three infectious states. No ratio was significantly different between survivors and non-survivors in the population of FIV-Ab-positive cats. MLR at diagnosis was significantly higher in FeLV-Ag-positive cats that died 1–3 years after diagnosis than in FeLV-Ag-positive cats still alive at 3 years (P=0.0284). None of the three ratios could predict retroviruses-positive cats that would survive to the end of the study. Overall the results indicate that NLR, MLR, and PLR are not significantly different among retrovirus statuses evaluated and had a very limited prognostic value for the survival time in retrovirus-positive cats.
•The utility of leukocyte ratios as prognostic markers in FeLV and FIV infections has not yet been investigated.•Monocyte-lymphocyte ratio (MLR) was significantly lower in FeLV-Ag-positive cats than in the negative cross-matched cats.•None of the leukocyte ratios could predict retroviruses-seropositive cats that would survive to the end of the study.•MLR at diagnosis was significantly higher in FeLV-Ag-positive cats that died 1-3 years after diagnosis.
On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an ...estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21} M_{⊙} and 66_{-18}^{+17} M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65 M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28} M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4} Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30} Gpc^{-3} yr^{-1}.
This paper presents the gravitational-wave measurement of the Hubble constant (H(0)) using the detections from the first and second observing runs of the Advanced LIGO and Virgo detector network. The ...presence of the transient electromagnetic counterpart of the binary neutron star GW170817 led to the first standard-siren measurement of H(0). Here we additionally use binary black hole detections in conjunction with galaxy catalogs and report a joint measurement. Our updated measurement is H(0) = 69(+16,-8) km/s Mpc (68.3% of the highest density posterior interval with a flat-in-log prior) which is an improvement by a factor of 1.04 (about 4%) over the GW170817-only value of 6(+17,-8) km/s Mpc. A significant additional contribution currently comes from GW170814, a loud and well-localized detection from a part of the sky thoroughly covered by the Dark Energy Survey. With numerous detections anticipated over the upcoming years, an exhaustive understanding of other systematic effects are also going to become increasingly important. These results establish the path to cosmology using gravitational-wave observations with and without transient electromagnetic counterparts.
The high-voltage system for the LHCb RICH hybrid photon detectors Arnaboldi, C.; Bellunato, T.; De Lucia, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2009, 2009-1-00, Letnik:
598, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We describe the characterization of the high-voltage (HV) distribution system designed and produced for the pixel hybrid photon detectors of the ring imaging Cherenkov counters of the LHCb ...experiment. The HV system consists of a series of printed circuit boards with a specific layout designed to prevent any discharge arising from high electric fields. The system has dedicated monitoring and control features to supervise HV set-up during data taking. The full production of the HV system has been now completed and all the boards have been fully characterized and installed in the detector, which is currently being commissioned.
Background. Aspergillus species are ubiquitous. We hypothesized that climatic variables that affect airborne mold counts affect the incidence of invasive aspergillosis (IA). Methods. Patients who ...received hematopoietic stem cell transplants (HSCTs) in geographically and climatically diverse regions (Seattle, WA, and Houston, TX) were examined. Cumulative incidence function, Kaplan-Meier analysis, and Cox proportional hazards regression were performed to examine the association between IA and season. Poisson regression analysis was performed to evaluate the seasonal patterns in IA rates and association with spore counts and climate. Results. In Seattle, the 3-month incidence of IA was 4.6% (5.7% in allograft recipients and 0.8% in autograft recipients). During the 10-year study period, there was a decrease in the incidence of IA among allogeneic HSCT recipients, corresponding to decreased risks during the nonsummer months; receipt of HSCTs during the summer months was associated with an increased hazard for IA (hazard ratio, 1.87; 95% confidence interval, 1.25–2.81) after adjustment for other known risks. The person-month IA rate in Seattle was positively associated with environmental spore counts, which increased with high temperature and low precipitation. No seasonal effect on IA was observed in Houston, where total spore counts were lower and not variable by climate. Conclusions. Climatic variables differentially affect airborne spore counts and IA risk in geographically disparate centers.
The gravitational-wave signal GW190521 is consistent with a binary black hole (BBH) merger source at redshift 0.8 with unusually high component masses, 85 − 14 + 21 M and 66 − 18 + 17 M , compared to ...previously reported events, and shows mild evidence for spin-induced orbital precession. The primary falls in the mass gap predicted by (pulsational) pair-instability supernova theory, in the approximate range 65-120 M . The probability that at least one of the black holes in GW190521 is in that range is 99.0%. The final mass of the merger ( 142 − 16 + 28 M ) classifies it as an intermediate-mass black hole. Under the assumption of a quasi-circular BBH coalescence, we detail the physical properties of GW190521's source binary and its post-merger remnant, including component masses and spin vectors. Three different waveform models, as well as direct comparison to numerical solutions of general relativity, yield consistent estimates of these properties. Tests of strong-field general relativity targeting the merger-ringdown stages of the coalescence indicate consistency of the observed signal with theoretical predictions. We estimate the merger rate of similar systems to be 0.13 − 0.11 + 0.30 Gpc − 3 yr − 1 . We discuss the astrophysical implications of GW190521 for stellar collapse and for the possible formation of black holes in the pair-instability mass gap through various channels: via (multiple) stellar coalescences, or via hierarchical mergers of lower-mass black holes in star clusters or in active galactic nuclei. We find it to be unlikely that GW190521 is a strongly lensed signal of a lower-mass black hole binary merger. We also discuss more exotic possible sources for GW190521, including a highly eccentric black hole binary, or a primordial black hole binary.
In patients with Hypertrophic Cardiomyopathy (HCM) S-ICD is usually the preferred option as pacing is generally not indicated. However, limited data are available on its current practice adoption and ...long-term follow-up.
Consecutive HCM patients with S-ICD implanted between 2013 and 2021 in 3 international centers were enrolled in this observational study. Baseline, procedural and follow-up data were regularly collected. Efficacy and safety were compared with a cohort of HCM patients implanted with a tv-ICD.
Seventy patients (64% males) were implanted with S-ICD at 41 ± 15 years, whereas 168 patients with tv-ICD at 49 ± 16 years. For S-ICD patients, mean ESC SCD risk score was 4,5 ± 1.9%: 25 (40%) at low-risk, 17 (27%) at intermediate and 20 (33%) at high-risk. Patients were followed-up for 5.1 ± 2.3 years. Two patients (0.6 per 100-person-years, vs 0.4 per 100 person-years with tv-ICD, p = 0.45) received an appropriate shock on VF, 17 (24%) were diagnosed with de-novo AF. Inappropriate shocks occurred in 4 patients (1.2 per 100-person-years, vs 0.9 per 100 person-years with tv-ICD, p = 0.74), all before Smart-Pass algorithm implementation. Four patients experienced device-related adverse events (1.2 per 100-person-years, vs 1 per 100 person-years with tv-ICD, p = 0.35%).
S-ICDs were often implanted in patients with an overall low-intermediate ESC SCD risk, reflecting both the inclusion of additional risk markers and a lower decision threshold. S-ICDs in HCM patients followed for over 5 years showed to be effective in conversion of VF and safe. Greater scrutiny may be required to avoid overtreatment in patients with milder risk profiles.
Abbreviations: S-ICD: Sub-Cutaneous ICD; HCM: Hypertrophic Cardiomyopathy; AF: Atrial fibrillation. Display omitted
•S-ICDs were often implanted in patients with an overall low-intermediate ESC SCD risk.•Life-threatening arrhythmias intermediate-low risk occurred less often than predicted, supporting latest ESC guidelines.•S-ICD was effective, generally safe and useful in the detection of sub-clinical AF occurring in 9% of the patients.
•Reports a large 3D benchmark study of pore-scale modeling methods.•Codes and methods varied widely in complexity and computational demand.•Both macroscopic and local measures of flow and solute ...transport were evaluated.•Comparisons were generally favorable among the various methods.•Differences observed support method selection depending on problem context.
Multiple numerical approaches have been developed to simulate porous media fluid flow and solute transport at the pore scale. These include 1) methods that explicitly model the three-dimensional geometry of pore spaces and 2) methods that conceptualize the pore space as a topologically consistent set of stylized pore bodies and pore throats. In previous work we validated a model of the first type, using computational fluid dynamics (CFD) codes employing a standard finite volume method (FVM), against magnetic resonance velocimetry (MRV) measurements of pore-scale velocities. Here we expand that validation to include additional models of the first type based on the lattice Boltzmann method (LBM) and smoothed particle hydrodynamics (SPH), as well as a model of the second type, a pore-network model (PNM). The PNM approach used in the current study was recently improved and demonstrated to accurately simulate solute transport in a two-dimensional experiment. While the PNM approach is computationally much less demanding than direct numerical simulation methods, the effect of conceptualizing complex three-dimensional pore geometries on solute transport in the manner of PNMs has not been fully determined. We apply all four approaches (FVM-based CFD, LBM, SPH and PNM) to simulate pore-scale velocity distributions and (for capable codes) nonreactive solute transport, and intercompare the model results. Comparisons are drawn both in terms of macroscopic variables (e.g., permeability, solute breakthrough curves) and microscopic variables (e.g., local velocities and concentrations). Generally good agreement was achieved among the various approaches, but some differences were observed depending on the model context. The intercomparison work was challenging because of variable capabilities of the codes, and inspired some code enhancements to allow consistent comparison of flow and transport simulations across the full suite of methods. This study provides support for confidence in a variety of pore-scale modeling methods and motivates further development and application of pore-scale simulation methods.
Integrins are heterodimeric cell surface receptors that mediate cell-cell and cell-extracellular matrix adhesion. These molecules play a role in processes such as cell growth and proliferation, ...differentiation, migration, cell trafficking, besides contributing to angiogenesis and tumor development. Given their biological role, integrins have been proposed as amenable targets in medicinal chemistry. In particular, αvβ3, αvβ5, αvβ6 and α5β1, integrins involved in tumor angiogenesis and metastasis, have been the subject of studies aimed at the discovery of novel cancer therapeutics. A large number of peptides and peptidomimetics based on the RGD (Arg-Gly-Asp) recognition sequence were developed in the past two decades as integrin ligands. Though such ligands have not been satisfactory as anti-angiogenic agents, their use as tools to achieve selective tumor targeting of anticancer drugs has been explored.
In this review, we summarize recent literature and patent applications in which integrin peptidic and peptidomimetic ligands were conjugated to chemotherapeutic agents both with stable or cleavable bonds to achieve tumor targeted drug delivery.
Relevant recent patents and literature in this field have been considered spanning the search from 2000 to 2016. Literature and patents were examined according to the different classes of cytotoxic drug targeted to integrins.
In spite of the promising features of the conjugates, none of them has entered clinical trials. New efforts are focused on innovative approaches in the field such as the synthesis of new integrin ligands able to target a single integrin type or the employment of nanoparticles based drug delivery systems.
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