In recent years, there has been a lot of interest in the research of cooperative censoring schemes. In this work, we compared the relative benefits of two competing length-of-life products using ...inverse Weibull lifetime products with a joint type-II hybrid censoring scheme (JHC-Type II). We initially examined the maximum likelihood estimators and their confidence intervals (CIs) for the unknown parameters based on JHC-Type II. Then, under the premise of independent gamma priors, we offer Bayes estimates of the parameters using squared error loss and LINEX loss functions. We used the Markov chain Monte Carlo method to create credible intervals and Bayesian estimates. Based on the parametric bootstrapping techniques known as Boot-p and Boot-t, we create two bootstrapping CIs. In addition, we do a Monte Carlo simulation experiment to track how well the aforementioned approaches work and to determine the corresponding confidence and credible intervals. Finally, to show how the approaches covered in this paper might be used, we consider a real physical dataset.
The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton–proton collisions at
s
=
13
TeV
in 2015 and 2016, is reported. The absolute ...luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a relative precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3
fb
-
1
in 2015 and 2016, with a relative precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
Pollution with heavy metals (HMs) is time- and concentration-dependent. Lead and zinc pollute the aquatic environment, causing severe health issues in aquatic animals.
Materials and ...methods
Nile tilapia, the predominant cultured fish in Egypt, were experimentally exposed to 10% of LC
50
of lead nitrate (PbNO
3
) and zinc sulfate (ZnSO
4
). Samples were collected in three different periods, 4, 6, and 8 weeks, in addition to a trial to treat the experimental fish infected with
Aeromonas hydrophila
, with an antibiotic (florfenicol).
Results
Liver enzymes were linearly upsurged in a time-dependent manner in response to HMs exposure. ALT was 92.1 IU/l and AST was 82.53 IU/l after eight weeks. In the eighth week of the HMs exposure, in the hepatic tissue, the levels of glutathione peroxidase (GPx), catalase (CAT), and metallothionein (MT) were increased to 117.8 U/mg prot, 72.2 U/mg prot, and 154.5 U/mg prot, respectively. On exposure to HMs, gene expressions of some cytokines were linearly downregulated in a time-dependent manner compared to the control. After four weeks of exposure to the HMs, the oxidative burst activity (OBA) of immune cells was decreased compared to the control 9.33 and 10.3 cells, respectively. Meanwhile, the serum bactericidal activity (SBA) significantly declined to 18.5% compared to the control 32.6% after eight weeks of exposure. Clinical signs of
A. hydrophila
infection were exaggerated in polluted fish, with a mortality rate (MR) of 100%. The re-isolation rate of
A. hydrophila
was decreased in fish treated with florfenicol regardless of the pollution impacts after eight weeks of HMs exposure.
Conclusion
It could be concluded that the immune suppression and oxidative stress resulting from exposure to HMs are time-dependent. Clinical signs and post-mortem lesions in polluted fish infected with
A. hydrophila
were prominent. Infected-Nile tilapia had weak responses to florfenicol treatment due to HMs exposure.
With the increased penetration of wind power, the influence of wind turbine generators on the grid power quality stipulates careful investigation and analysis. Direct driven permanent magnet ...synchronous generator (PMSG) with a back-to-back converter set is one of the promising technologies in wind power generation schemes. In this paper, comprehensive models of wind turbine are used to analyze power and voltage fluctuations. The short time flicker index is used to assess the voltage fluctuation emitted. The control scheme of the grid-side converter is supported with a voltage regulation loop to reduce flicker emission. The effects of grid and site parameters on voltage fluctuation are investigated. Simulation results show that reduced flicker emissions are given when the developed voltage regulation loop is activated. Reasonable values of grid and site parameters contribute in the minimization of voltage fluctuation and flicker emission levels.
A
bstract
A search is presented for physics beyond the standard model (SM) using electron or muon pairs with high invariant mass. A data set of proton-proton collisions collected by the CMS ...experiment at the LHC at
s
= 13 TeV from 2016 to 2018 corresponding to a total integrated luminosity of up to 140 fb
−
1
is analyzed. No significant deviation is observed with respect to the SM background expectations. Upper limits are presented on the ratio of the product of the production cross section and the branching fraction to dileptons of a new narrow resonance to that of the Z boson. These provide the most stringent lower limits to date on the masses for various spin-1 particles, spin-2 gravitons in the Randall-Sundrum model, as well as spin-1 mediators between the SM and dark matter particles. Lower limits on the ultraviolet cutoff parameter are set both for four-fermion contact interactions and for the Arkani-Hamed, Dimopoulos, and Dvali model with large extra dimensions. Lepton flavor universality is tested at the TeV scale for the first time by comparing the dimuon and dielectron mass spectra. No significant deviation from the SM expectation of unity is observed.
Transverse thoracic block is a new perioperative analgesic method for post-sternotomy discomfort. This study discusses the efficacy of an ultrasound-guided transversus thoracic muscle plane block ...(TTPB) in patients undergoing heart surgery, including sternotomy.
In this prospective trial, 60 patients were randomly assigned to two groups: transversus (T) or general anesthesia (GA). Patients in the T group received TTPB with GA and 15 mL of 0.25% bupivacaine was administered on either side. Patients in the GA group received TTPB along with GA, but 15 mL saline was injected on either side instead. The patients were followed up postoperatively. The percentage of patients receiving additional opioids, extubation time, intensive care unit (ICU) length, postoperative morphine dose, and adverse events were documented.
The percentage of patients requiring additional morphine was significantly lower in the T group (p<0.015). Pain scores were comparable between the groups at extubation time and 18 h postoperatively. At 8, 12, and 24 h after surgery, pain scores in the T group were significantly lower (P<0.001). The total amount of morphine required after surgery was much lower in the T group (8±0.74 mg), and the duration to initial analgesic necessity was significantly greater in the GA group (P<0.001). Patients in the GA group had a considerably longer ventilation time (11.07±0.64) (P<0.001). The ICU stay in the T group was substantially shorter (P<0.001), and postoperative complications were comparable.
For patients undergoing heart surgery, TTPB offers sufficient postoperative pain control, resulting in lower pain scores, lower postoperative analgesic doses, shorter extubation times, and shorter ICU stay lengths.
Background
Systemic lupus erythematosus (SLE) is a chronic multi-systemic autoimmune disease. SLE patients may experience a wide range of physical, psychological, and social perception of well-being ...influenced by the patient illness that are not always fully captured by descriptions of the disease’s physiological consequences alone. Nowadays, patients with SLE have a better survival than decades ago, nevertheless still experience a low health related quality of life (HRQoL). Assessing disease activity in SLE is crucial to the physician as it forms the basis for treatment decisions, moreover careful evaluation for respiratory involvement should be routinely considered. More chronic lung disease related to SLE can have a significant negative effect on patient well-being and physical performance status and are detrimental to quality of life.
Objective
The aim of this study was to evaluate quality of life changes in SLE patients using Lupus QoL scale, assessing their correlation with different disease aspects particularly pulmonary manifestations and predictors for worse QoL.
Materials and methods
Total of 60 SLE patients, who fulfilled the 2012 Systemic Lupus International Collaborating Clinics (SLICC) criteria, were enrolled in this study. Disease activity was measured by systemic lupus erythematosus disease activity index (SLEDAI) and quality of life was assessed by Lupus QoL. Pulmonary evaluation included pulmonary function tests parameters (PFTs), mMRC dyspnea scale, HRCT score, and pulmonary damage index.
Results
Lupus QoL had a strong significant correlations with PFTs FEV1, FVC, and DLCO (r = 0.79, 0.78, 0.76, p < .001), respectively}, while Lupus QoL had strong negative correlations with both mMRC dyspnea scale and HRCT score (r = −0.96, −0.85, p < .001), respectively, and moderate negative correlation with neuropsychiatric lupus (NPSLE) (r = −0.61, p < .001). Weak negative correlations were found between Lupus QoL, photosensitivity, alopecia, Raynaud’s and renal affection (r = −0.29, −0.30, −0.30, 0.38, p = .03, .02, .02, .002), respectively. NPSLE and pulmonary involvement were the most consistent predictors of low HRQoL contributing 36% and 18% of the variance of Lupus QoL, respectively.
Conclusion
Lupus QoL is negatively correlated with different SLE clinical parameters particularly pulmonary manifestations. Neuropsychiatric, pulmonary, renal affection, and SLEDAI are the best determinants for worse Lupus QoL.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
It is crucial to have a dependable and precise channel model in order to study the properties of millimeter wave (mmWave) propagation. The Quasi-deterministic (QD) channel model is employed in this ...viewpoint, which describes the propagation of mm-Wave as a group of reflected and scattered rays originating from a complex environmental setup. These rays are assumed to travel in clusters, with each cluster consisting of a deterministic ray followed by postcursor rays and preceded by precursor rays. The summation of these rays is the number of multiple path components (MPCs) of each cluster. However, this comes at the cost of higher computational complexity for the channel model, which can hinder the simulation's scalability. To simplify the QD channel model while maintaining accuracy, one option is to decrease the number of MPCs. In this paper, we present an analysis of path gains (PGs) of specular and diffused rays to reduce the total number of MPCs. Specifically, we propose two different reduction methods namely: i) the reduced post rays (RPR) method ii) the removed surfaces post rays (RSPR) method. The computational performance of the proposed methods is investigated in terms of computational time, and complexity. Additionally, the accuracy validation compared to the original QD model is evaluated in terms of PG cumulative distribution function (CDF), signal-to-noise ratio (SNR), and intra-cluster statistics. The proposed methods' complexity and accuracy were assessed by examining measured data from indoor and outdoor environments at 60 GHz and 28 GHz, respectively. Both first and second-order reflection orders were tested to illustrate the balance between the two variables. The simplified methods suggested can decrease computational time by approximately 16% and 11% for RSPR and RPR schemes, respectively, when compared to the original QD.
An experimental study of the effect of dwell time and normal load on static friction in a spherical polymer contact is presented. The measurements are done for different diameters of spherical tip ...specimens made of polytetrafluoroethylene (PTFE). These specimens are loaded against a flat glass substrate by different normal loads and under different dwell times prior to applying tangential loading. It is found that the experimental immediate friction coefficient (after zero dwell time) is about an order of magnitude smaller than the theoretical results of a model proposed by Malamut et al. S. Malamut, Y. Kligerman, I. Etsion, Tribol. Lett. 35 (2009) 159–170. However, the creep components of the static friction force and static friction coefficients fairly agree with the model predictions.
•The effect of dwell time and normal load on the static friction is studied experimentally.•A comparison of the results is made with these of a previously published theoretical model.•The experimental immediate friction coefficient is about an order of magnitude smaller than the model prediction.•The creep components of the static friction force and static friction coefficients fairly agree with the model predictions.
Intradialytic hypertension (IDH) is an important emerging complication in hemodialysis patients. No study has examined the diagnostic markers of various risk factors for the occurrence of IDH in ...chronic hemodialysis patients. Therefore, our study aimed to assess the use of nitric oxide (NO) as a marker of IDH among end-stage renal disease patients. The patients were divided into two groups: Group I (40 patients) with IDH and Group II (40 patients) without IDH. For all participants, a full medical history was taken, followed by laboratory examinations to measure the level of NO and a clinical examination. The dose of erythropoietin per week, the level of intact parathyroid hormone, and platelet count were significantly higher in Group I than in Group II, whereas the mean level of NO (2.10 ± 1.23 pmol/L) was highly significantly lower in patients with IDH (P < 0.001). Multivariate analysis showed that hypertension (odds ratio: 1.824, 95% confidence interval: 1.273-2.982) and the level of NO (odds ratio: 1.68, 95% confidence interval: 1.13-2.97) were independent risk factors for IDH. The receiver operating characteristic curve showed that the cutoff point of NO was 2.52 μmol/L to differentiate between cases with and without IDH (area under the curve = 0.844). Our findings support previous research regarding the involvement of endothelial dysfunction and a higher sodium level in the pathogenesis of IDH. We also found that the NO level had a good diagnostic value for the occurrence of IDH at a cutoff of 2.52 μmol/L.
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