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Spread application of wireless sensor networks (WSNs), has led many researchers aiming at energy optimization in these networks. The Proposed Energy Efficient Harmony Search Routing Algorithm (PEEHSRA) in accordance with a novel energy model is stated in this study to minimize the amount of energy consumption in WSNs. We first proposed an energy model on the basis of modulation scheme parameters for multi-hop transmission. Then, in order to develop a harmony search routing algorithm, pitch adjustment rate in the harmony memory was introduced based on both, the proposed energy model, and the node’s distance. Also, an energy-efficient fitness function was determined, which results in the most energy-efficient route for the network. At the end, four modulations including MQAM, MQPSK, OQPSK and MFSK were applied and the most energy-efficient one with corresponding parameters was specified. By comparing the results of the proposed method to the state-of-the-art studies, the improvements in extending the lifetime of the network was proved. These findings seem quite useful in designing an energy-efficient multi-hop WSN and pave the way for enhancement of the widespread applications in these networks.

In this report, we have investigated the structural, electronic and magnetic properties of porous alumina using theoretical results and experimental measurements. To simulate the bulk and porous Al2O3 supercell in a monoclinic structure with C2/m space group, the DFT method was employed. The results show that the porous alumina has a lower band gap compared to the nonporous alumina, and the DFT simulation confirms the existence of ferromagnetic properties in porous samples.

The optical and electronic properties of boron nitride nanotubes have been studied using the full potential linear augmented plane wave method in the framework of density functional theory. The electronic properties such as band structure and density of states have been investigated using the generalized gradient approximation. In addition, the optical parameters of boron nitride nanotube (6,0) have been investigated such as real and imaginary parts of the dielectric function, electron energy loss function, refractive index, extinction coefficient, and optical conductivity. The obtained values are in better agreement with the available experimental data.

Background Microvascular and macrovascular thrombotic events are among the hallmarks of coronavirus disease 2019 (COVID-19). Furthermore, the exuberant immune response is considered an important driver of pulmonary and extrapulmonary manifestations of COVID-19. The optimal management strategy to prevent thrombosis in critically-ill patients with COVID-19 remains unknown. Methods The Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) and INSPIRATION-statin (INSPIRATION-S) studies test two independent hypotheses within a randomized controlled trial with 2 × 2 factorial design. Hospitalized critically-ill patients with reverse transcription polymerase chain reaction confirmed COVID-19 will be randomized to intermediate-dose versus standard dose prophylactic anticoagulation. The 600 patients undergoing this randomization will be screened and if meeting the eligibility criteria, will undergo an additional double-blind stratified randomization to atorvastatin 20 mg daily versus matching placebo. The primary endpoint, for both hypotheses will be tested for superiority and includes a composite of adjudicated acute arterial thrombosis, venous thromboembolism (VTE), use of extracorporeal membrane oxygenation, or all-cause death within 30 days from enrollment. Key secondary endpoints include all-cause mortality, adjudicated VTE, and ventilator-free days. Key safety endpoints include major bleeding according to the Bleeding Academic Research Consortium definition and severe thrombocytopenia (platelet count 3 times upper normal limit and clinically-diagnosed myopathy. The primary analyses will be performed in the modified intention-to-treat population. Results will be tested in exploratory analyses across key subgroups and in the intention-to-treat and per-protocol cohorts. Conclusions INSPIRATION and INSPIRATON-S studies will help address clinically-relevant questions for antithrombotic therapy and thromboinflammatory therapy in critically-ill patients with COVID-19., Highlights • The optimal anticoagulant regimen for critically-ill patients with COVID-19 remains unknown. • It is unknown if pleiotropic effects of statins may reduce thromboinflammation in COVID-19. • This manuscript summarizes the rationale and methodology of the INSPIRATION and INSPIRATION-S studies. • The manuscript provides a summary about other anticoagulation trials and statin trials in COVID-19.

Zinc phosphide is a gray to black powder mainly used as a rodenticide. In contact with gastric fluid, it releases phosphine which is the main toxic material of this compound. Phosphine interferes with oxidative respiratory cycle of the cells, but is generally expected to manifest its toxicity with prodromal signs and symptoms including abdominal pain, nausea and vomiting, metabolic acidosis, and increased liver function tests. A 64-year-old man was referred to our center with the history of ingestion of three full table spoons of zinc phosphide powder with only a mild GI discomfort. Abdominal X-ray revealed radiopaque material in epigastric and abdominal right upper quadrant. Despite treatment with polyethylene glycol and completely normal vital signs and lab tests, he experienced sudden cardiac arrest 19 h after admission. Autopsy showed clues of focal myopathy and fibrosis with evidences of ischemia and congestion in cardiac tissue, pulmonary edema, shrunken bilateral kidneys, and nutmeg yellow liver. Toxicology panel confirmed the presence of phosphine and zinc phosphide in the gastric fluid. The patient deteriorated suddenly despite being completely symptom-free during the hours preceding cardiovascular arrest. Since the cardiopulmonary injury is the most rampant cause of early death, checking of the cardiac enzymes and cardiac monitoring could be beneficial for early detection and efficient management of these patients.

Background Abdominal pain may be a presenting symptom of lead poisoning and is often difficult to diagnose. This study aimed to determine the prevalence of abdominal pain in patients seen in the Laghman Hakim Hospital ED and GI clinic who were lead-intoxicated, with or without opiate use disorder. Methods Between July 2017 and January 2018, patients seen in the ED and GI clinic of Loghman Hakim Hospital with unexplained abdominal pain or abdominal pain resistant to treatment were enrolled. Informed consent was obtained from potential enrollees. For standardization, a pre-designed data collection tool was developed for uniform data acquisition. Opiate use was determined historically. For this study, lead poisoning was defined as a blood lead level (BLL) greater than or equal to 30 μg/dL (1.45 μmol/L) with concomitant GI symptoms. Results Of 125 patients admitted, 28 (22.4%) had BLLs higher than 30 μg/dL. None of the patients had signs and symptoms of opioid withdrawal syndrome during evaluation. Elevated BLLs were significantly correlated with oral opium use/abuse, history of addiction for over the preceding 12 years. The daily opium use was more than 2.75 g. There was a statistical correlation between lead toxicity and abdominal pain consistency and intensity, constipation, and paresthesias. Anemia, leukocytosis, and abnormal liver enzyme tests were laboratory findings associated with lead toxicity. Four patients died, one of whom was diagnosed with lead toxicity. Conclusion Lead toxicity should be considered in the potential differential diagnosis of severe and resistant abdominal pain in patients referring to general EDs or GI clinics if a positive history of opium abuse exists.

The effects of doping Fe on optical, magnetic and electronic properties of the boron nitride (BN) sheet have been studied by optimizing the BN structure. Studying these properties gets valuable information about dielectric function, optical conductivity, absorption, energy loss function, and extinction index, along with reflectivity and refraction index of pure BN and in the presence of Fe impurity [substituting one Fe atom on B (FeB), N (FeN) or two Fe atoms with B and N (FeBN) sites] for both perpendicular (E||c) and parallel (E||a) electromagnetic wave polarization. Results inferred to the metallic behavior of FeN/BN and half-metallic behavior of FeB/BN and FeBN/BN. Moreover, net magnetic moments were estimated at 3.54, 4 and 2 µB per cell for FeB/BN, FeN/BN and FeBN/BN, respectively. As can be seen, Fe/BN, due to its magnetic properties, can be considered as a good candidate to be applied in spintronic applications as a magnetic sensor. FeN/BN monolayer is also a good infrared reflector and can be used as an infrared mirror.

The present study considers detection of the weak Swerling targets which exist in the clutter Doppler cell of the Weibull-distributed ground-based clutter by means of Independent Component Analysis (ICA). We present a new detector based on convolutive ICA that is independent of target and clutter statistical distribution and has no need to the previous knowledge of the radar signals. For the detection of radar target using ICA, there are some problems that are solved by two wisely proposed approach through the detector. Synthetic generated clutter and target are used to show quantitatively and qualitatively the capability of the proposed ICA-based detector. Also, the method is tested against real-life data. Finally, the computational time is considered and the superiority of the detector is shown by a comparison between the proposed and a typical Neyman-Pearson (NP) detector.

Objective To assess the effect of statin treatment versus placebo on clinical outcomes in patients with covid-19 admitted to the intensive care unit (ICU). Design INSPIRATION/INSPIRATION-S was a multicenter, randomized controlled trial with a 2×2 factorial design. Results for the anticoagulation randomization have been reported previously. Results for the double blind randomization to atorvastatin versus placebo are reported here. Setting 11 hospitals in Iran. Participants Adults aged ≥18 years with covid-19 admitted to the ICU. Intervention Atorvastatin 20 mg orally once daily versus placebo, to be continued for 30 days from randomization irrespective of hospital discharge status. Main outcome measures The primary efficacy outcome was a composite of venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or all cause mortality within 30 days from randomization. Prespecified safety outcomes included increase in liver enzyme levels more than three times the upper limit of normal and clinically diagnosed myopathy. A clinical events committee blinded to treatment assignment adjudicated the efficacy and safety outcomes. Results Of 605 patients randomized between 29 July 2020 and 4 April 2021 for statin randomization in the INSPIRATION-S trial, 343 were co-randomized to intermediate dose versus standard dose prophylactic anticoagulation with heparin based regimens, whereas 262 were randomized after completion of the anticoagulation study. 587 of the 605 participants were included in the primary analysis of INSPIRATION-S, reported here: 290 were assigned to atorvastatin and 297 to placebo (median age 57 years (interquartile range 45-68 years); 256 (44%) women). The primary outcome occurred in 95 (33%) patients assigned to atorvastatin and 108 (36%) assigned to placebo (odds ratio 0.84, 95% confidence interval 0.58 to 1.21). Death occurred in 90 (31%) patients in the atorvastatin group and 103 (35%) in the placebo group (odds ratio 0.84, 95% confidence interval 0.58 to 1.22). Rates for venous thromboembolism were 2% (n=6) in the atorvastatin group and 3% (n=9) in the placebo group (odds ratio 0.71, 95% confidence interval 0.24 to 2.06). Myopathy was not clinically diagnosed in either group. Liver enzyme levels were increased in five (2%) patients assigned to atorvastatin and six (2%) assigned to placebo (odds ratio 0.85, 95% confidence interval 0.25 to 2.81). Conclusions In adults with covid-19 admitted to the ICU, atorvastatin was not associated with a significant reduction in the composite of venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation, or all cause mortality compared with placebo. Treatment was, however, found to be safe. As the overall event rates were lower than expected, a clinically important treatment effect cannot be excluded. Trial registration ClinicalTrials.govNCT04486508.

Background Thrombotic complications are considered among the main extrapulmonary manifestations of coronavirus disease 2019 (COVID-19). The optimal type and duration of prophylactic antithrombotic therapy in these patients remain unknown. Methods This article reports the final (90-day) results of the Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) study. Patients with COVID-19 admitted to intensive care were randomized to intermediate-dose versus standard-dose prophylactic anticoagulation for 30 days, irrespective of hospital discharge status. The primary efficacy outcome was a composite of adjudicated venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation (ECMO), or all-cause death. The main safety outcome was major bleeding. Results Of 600 randomized patients, 562 entered the modified intention-to-treat analysis (median age [Q1, Q3]: 62 [50, 71] years; 237 [42.2%] women), of whom 336 (59.8%) survived to hospital discharge. The primary outcome occurred in 132 (47.8%) of patients assigned to intermediate dose and 130 (45.4%) patients assigned to standard-dose prophylactic anticoagulation (hazard ratio [HR]: 1.21, 95% confidence interval [CI]: 0.95–1.55, p = 0.11). Findings were similar for other efficacy outcomes, and in the landmark analysis from days 31 to 90 (HR: 1.59, 95% CI: 0.45–5.06). There were 7 (2.5%) major bleeding events in the intermediate-dose group (including 3 fatal events) and 4 (1.4%) major bleeding events in the standard-dose group (none fatal) (HR: 1.82, 95% CI: 0.53–6.24). Conclusion Intermediate-dose compared with standard-dose prophylactic anticoagulation did not reduce a composite of death, treatment with ECMO, or venous or arterial thrombosis at 90-day follow-up.

Abdominal pain may be a presenting symptom of lead poisoning and is often difficult to diagnose. This study aimed to determine the prevalence of abdominal pain in patients seen in the Laghman Hakim Hospital ED and GI clinic who were lead-intoxicated, with or without opiate use disorder.Between July 2017 and January 2018, patients seen in the ED and GI clinic of Loghman Hakim Hospital with unexplained abdominal pain or abdominal pain resistant to treatment were enrolled. Informed consent was obtained from potential enrollees. For standardization, a pre-designed data collection tool was developed for uniform data acquisition. Opiate use was determined historically. For this study, lead poisoning was defined as a blood lead level (BLL) greater than or equal to 30 μg/dL (1.45 μmol/L) with concomitant GI symptoms.Of 125 patients admitted, 28 (22.4%) had BLLs higher than 30 μg/dL. None of the patients had signs and symptoms of opioid withdrawal syndrome during evaluation. Elevated BLLs were significantly correlated with oral opium use/abuse, history of addiction for over the preceding 12 years. The daily opium use was more than 2.75 g. There was a statistical correlation between lead toxicity and abdominal pain consistency and intensity, constipation, and paresthesias. Anemia, leukocytosis, and abnormal liver enzyme tests were laboratory findings associated with lead toxicity. Four patients died, one of whom was diagnosed with lead toxicity.Lead toxicity should be considered in the potential differential diagnosis of severe and resistant abdominal pain in patients referring to general EDs or GI clinics if a positive history of opium abuse exists.

Background: The lack of expressing opinions of employees working in organizations can cause a phenomenon called organizational silence. Organizational silence has a damaging effect on employee’s productivity. The organizational sound and silence about organizational performance are currently one of the fundamental organizational challenges. Materials and Methods: In this descriptive, correlational study, regression analysis was used to analyze the relationship between the studied factors. Using the Morgan table and stratified random sampling method, 317 subjects were selected and assessed by the structural equation modeling (SEM) with SmartPLS software. Results: The results showed a significant relationship between organizational silence and performance with a path coefficient of 0.179 and a significant difference of 3.289. Also, there was a significant relationship between organizational voice and performance with a path coefficient of 0.393 and a significant level of 6.766. Besides, a significant relationship existed between organizational voice and ethical leadership with a path coefficient of 0.247 and a significance level of 3.883, and finally, between the focal variables (silence and organizational voice) and organizational performance with moral leadership with a path coefficient of 0.315 and a significance of 5,485. Accordingly, the results indicated the suitability of the model. Conclusion: The results showed a significant relationship between organizational sound and silence and employee’s performance, considering the mediating role of moral leadership in the organization. It can be concluded that one of the essential tasks of firefighters and firefighting leaders and managers is to identify and break the climate of silence and motivate the employees to talk in their workplace for subsequently improving their performances.

Detection of a noisy signal is a complex process. Many radar systems are working in an environment where the signal processing parts cannot overcome the effects of interference sources due to their high power. These sources of conflict may completely erode the signal or may make a mistake in deciding. It may make the return of the echoes of the goals difficult. To solve this problem, the detector processor can use a new algorithm to estimate noise power and then can set the threshold in different positions of the cell under test. The proposed algorithm, by differentiating between homogeneous and interference environments in a multitarget structure, selects a set of reference cells that surround the cell under test to estimate the unknown noise/clutter and determine the effective threshold. Then, to evaluate the performance of cell averaging of constant false alarm rate (CA-CFAR), censored mean level detector CFAR (CMLD-CFAR), and excision CFAR (EX-CFAR) detectors, we compared threshold, false alarm, and detection probability in terms of different correlation coefficients. The values were obtained using simulation by MATLAB software. The simulation results show that the excision parameter, by adding to the window of the reference cells that surround the cell under test, reduces the effects of background noise on the received signal. We conclude from the proposed method that the hybrid detector not only has higher quality detection interactions in heterogeneous environments but also has relatively less computational complexity than CA-CFAR, CMLD-CFAR, and EX-CFAR detectors.

Objective In the current work, we investigated the cytotoxic and apoptotic effects of Thymoquinone (TQ), an active compound of Nigella sativa (N. sativa) and Cis-platinum, on normal renal epithelial (GP-293) and human renal adenocarcinoma cell lines (ACHN). Methods GP-293 and ACHN cell lines were cultured in Dulbecco's modified Eagle's medium (DMEM) with 10% Fetal bovine serum (FBS) and 1% penicillin plus streptomycin antibiotic. The MTT assay was used for cellular viability assessment. Viability of cells was observed using inverted light microscope 24, 48 and 72 h after exposure of the cells to various concentrations of TQ (1, 2.5, 5, 10, 50 and 100 μg/ml) and Cis-platinum (0.5, 1, 1.5, 2, 3, 6 and 12.5 μg/ml). Moreover, apoptosis was analyzed with a flow-cytometry method. The untreated cells were considered as control group. Results Morphological changes such as reduced cell number and increased intercellular distance and reduced cell viability in ACHN and GP-293cell lines were observed in both TQ and Cis-platinum groups; however, Cis-platinum had greater effect on ACHN cell line than GP-293 cell line. In addition, GP-293 cell line was more sensitive to TQ compared to ACHN cell line. Furthermore, TQ and Cis-platinum had apoptotic effects on both ACHN and GP-293 cell lines. Conclusion Our findings demonstrated that TQ and Cis-platinum had cytotoxic and apoptotic effects on both cell lines, However, GP-293 cell line was more sensitive to TQ. Additionally, Cis-platinum was more effective on ACHN cell line than on GP-293 cell line.

Using the first principle calculations, the structural, electronic and optical properties of the monolayer graphene-like MoX2 sheet are calculated. Our results show that the chalcogenide atoms in the stability and the lattice parameters of the MoX2 sheet have a key role, although it is known that the electronic properties are more dependent on the metal atoms in these sheets. Our data also confirm semiconductor behavior of the MoX2 monolayers with direct band gap for S, Se and Te chalcogenides. Compared with the bulk compounds, they have similar structural properties but represent unique electronic and optical properties that can be used in nano-devices, nano-electronics and so on. In this work, the investigation of the chalcogenide atoms role in modifying the optical properties of these single-layer sheets, such as absorption and refraction coefficients, is carried out; the dielectric constant plays an important role. We also try to study the possibility of using these compounds on the solar energy industries and optical devices.

Structural and optical properties of graphene with a vacancy and B, N, O and F doped graphene have been investigated computationally using density functional theory (DFT). We find that B is a p-type while N, O and F doped graphene layers, as well as graphene with a vacancy are n-type semiconductors. Optical properties for both cases of in plane E ⊥ c and out of plane E ‖ c polarization of light are investigated. It is observed that with the increase in the number of electrons entering the supercell, the amount of absorption of the system decreases and the absorption peaks are transferred to higher energies (blue shift).

A method was proposed in this paper for detecting radar targets in sea clutter by solving the composite hypothesis testing for the quasi-optimum detector. The quasi-optimal detector and the...

Using a first-principles calculation, the electronic and optical properties of graphene with B, N, O and F atom adsorption was studied. For the adatoms studied, distortion of the graphene layer is significant and causes a change in hybridization from sp2 to sp3. Also, it was found that B atom adsorption on graphene is n-type, F and O atoms adsorption on graphene are p-type semiconductor, while N adsorption has a metal behavior. N-absorbed graphene shows a magnetic moment, while B-, O-, and F-absorbed graphene show no magnetic moment. The optical absorption spectra of monolayer graphene have been calculated for the cases of in-plane (E⊥c), out of plane (E||c) and 45° polarization of light to the plane of the graphene layer and have been compared with atom adsorption on graphene. For (E⊥c), it was observed that the graphene was an optical sensor for finding F gas. In (E||c), it is an optical sensor for detecting the B atom in the environment.

The discrete polynomial-phase transform (DPT) method estimate chirp rate and central frequency of LFM signal based on sequential estimation of polynomial phase parameters. This method uses Nonlinear Least Squares (NLS) technique (based on FFT) to estimate phase parameters of the LFM signal. Although NLS enjoys a high level of statistical accuracy, it entails a lot of calculations. In this paper, in order to enhance the precision of estimation and also to reduce the calculations in DPT method, a technique called "combined" is proposed and used in DPT method in order to estimate chirp rate and central frequency of LFM signal .The combined technique firstly provides an initial estimate of frequency interval based on NLS criterion in single-exponential mode, then using initial estimation and Random Basis Functions method (RBF). Simulation results are presented to demonstrate better performance of DPT method by combined technique in order to estimate phase parameters of LFM signal as compared with the existing techniques.

In this study, the effect of magneto-impedance (MI) in three-layer structures was studied. Ni/Cu/Fe sandwiched films were prepared by thermal evaporation on glass substrates. MI sensor impedance as a function of external magnetic field and the driving frequency was measured. MI ratios were obtained as large as 68% and 95% at 5 MHz and 15 MHz, respectively. The results showed that the three-layer structures had a dramatic increase in performance with respect to the single-layer magneto-impedance films.

Due to low dimensionality, the controlled stacking of the graphene films and their electronic properties are susceptible to environmental changes including strain. The strain-induced modification of the electronic properties such as the emergence and modulation of bandgaps crucially depends on the stacking of the graphene films. However, to date, only the impact of strain on electronic properties of Bernal and AA-stacked bilayer graphene has been extensively investigated in theoretical studies. Exploiting density functional theory and tight-binding calculation, we investigate the impacts of in-plane strain on two different class of commensurate twisted bilayer graphene (TBG) which are even/odd under sublattice exchange (SE) parity. We find that the SE odd TBG remains gapless whereas the bandgap increases for the SE even TBG when applying equibiaxial tensile strain. Moreover, we observe that for extremely large mixed strains both investigated TBG superstructures demonstrate direct-indirect bandgap transition., 8 pages, 8 figures