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Let $R$ be a commutative ring with identity, and $ \mathrm{A}(R) $ be the set of ideals with non-zero annihilator. The annihilating-ideal graph of $ R $ is defined as the graph $AG(R)$ with the vertex set $ \mathrm{A}(R)^{*}=\mathrm{A}(R)\setminus\lbrace 0\rbrace $ and two distinct vertices $ I $ and $ J $ are adjacent if and only if $ IJ=0 $. In this paper, we characterize all positive integers $n$ for which $AG(\mathbb{Z}_n)$ is identifiable.

In this article, we present a futuristic perspective on GaN integrated circuit technology, discuss technical challenges that hinder leveraging the capabilities of the GaN process, and provide recommendations to push its limits of integration and functionality. We explore the limitations of current GaN processes at the process, circuit, and system levels, and present some potential developments to mitigate these limitations. The most recent progresses in GaN circuits has been inspired by the quest for higher performance, which has influenced innovations in circuit and system architectures. A promising solution is to pursue a functionality-oriented design paradigm in parallel with the traditional performance-oriented design approach. A review of state-of-the-art GaN transceivers indicates that most comprise merely a power amplifier (PA), a low-noise amplifier (LNA), and transmit-receive (T/R) switches. We propose three disruptive directions that potentially can reshape the future of highly integrated GaN systems, including a digital PA, an integrated sensing and communication (ISAC) transceiver, and GaN-CMOS chiplets in package, and investigate their prospects and challenges.

In this article, we present a hybrid quantum-classical generative adversarial network (GAN) for near-term quantum processors. The hybrid GAN comprises a variational generator and a discriminator quantum neural network, which are trained using a classic computer. The generator network is realized using angle-encoding and variational quantum circuits. The discriminator network is realized using multi-stage trainable encoding quantum circuits. A modular design approach is proposed for quantum neural networks which allows control on their depth to compromise accuracy and circuit complexity. Moreover, this modular approach makes the quantum neural networks amenable to scaling up the dimension of dataset and the number of qubits. Gradients of the loss functions are derived using the same quantum circuits used for the implementation of quantum neural networks to prevent the need for extra quantum circuits or auxiliary qubits. The quantum simulations are performed using the IBM Qiskit open-source software development kit (SDK), while the training of the hybrid quantum-classical GAN is conducted using the mini-batch stochastic gradient descent (SGD) optimization on a classic computer. The hybrid quantum-classical GAN is realized using a two-qubit system with different discriminator network structures. The best performance is achieved using a five-stage discriminator network comprising 63 quantum gates and 31 trainable parameters, with the Kullback-Leibler (KL) and Jensen-Shannon (JS) divergence scores of 0.39 and 0.52, respectively, for the similarity between the real and generated data distributions.

Abstract Background The prevalence of resistant hospital infections in the intensive care unit (ICU) increases mortality and antibiotic resistance. COVID-19 pandemic may have unintended impact on nosocomial infections (NI) and the prevalence of resistant microorganism. Methodology The present non-interventional study was performed by a pre and a post survey each lasting 8 months before (March–October 2019) and after (March–October 2020) the onset of COVID-19 pandemic in three ICU’s, not allocated to COVID-19 patients, in Nemazee Hospital, Shiraz, Iran. The rates of the following nosocomial infections were compared at pre- and post-pandemic period: ventilator associated pneumonia (VAP), central line associated blood stream infection (CLABSI), catheter-associated urinary tract infections (CAUTI) and incidence of multiple drug resistance (MDR) pathogens. Results Pre-pandemic and pandemic incidence of VAP was 23.5 and 17.2 cases per 1000 device-days, respectively; an absolute decrease of 27%. The main reason for the decrease in the rate of VAP during the pandemic was a significant decrease in the rate of VAP caused by Acinetobacter baumannii; from 39 to 17% in total VAP episodes. The rate of VAP associated with other microorganisms remained relatively unchanged from 14.2 cases in pre-pandemic period to 14.3 cases per 1000 MV-days during the pandemic (P = 0.801). Pre-pandemic incidence of CLABSI was 7.3 cases and, in pandemic period, was 6.5 cases per 1000 device-days (IRR = 0.88, 95% CI 0.43–1.73, P = 0.703). Pre-pandemic incidence of CAUTI was 2 and in pandemic period, was 1.4 cases per 1000 device-days (IRR = 0.70, 95% CI 0.22–1.98, P = 0.469). Conclusion The results of the present study showed a decrease in the incidence of VAP in critically ill non-COVID-19 patients during the pandemic compared to before the pandemic, especially regarding Acinetobacter baumannii.

GaN integrated circuit technologies have dramatically progressed over the recent years. The prominent feature of GaN high-electron mobility transistors (HEMTs), unparalleled output power densities, has created a paradigm shift in the established and emerging high-power applications. In this article, we present a review on the developments and prospects of GaN integrated circuit power amplifiers (PAs). The progress of GaN transistors including improvements in their important features, i.e., supply voltage, substrate material, transistor scaling approach, and device modeling are elaborated and the current state-of-the-art processes with 20-nm gate length, 450 GHz cut-off frequency, and over 600 V supply voltage are discussed. We also investigate developments in the GaN integrated circuit PA architectures and their implementation challenges including the reactive matching PAs capable of delivering over 100 W output power and operating up to 200 GHz, PA linearity, back-off efficiency enhancement, reconfigurable PAs, and distributed PA architectures. Finally, we discuss the prospects of GaN technology and possible future improvements, in transistor and circuit levels, which can advance performance and functionality of GaN integrated circuits.

Let R be a commutative ring with identity and Nil(R) be the set of nilpotent elements of R. The nil-graph of ideals of R is defined as the graph AG_N(R) whose vertex set is {I:(0)and there exists a non-trivial ideal such that and two distinct vertices and are adjacent if and only if . Here, we study conditions under which is complete or bipartite. Also, the independence number of is determined, where is a reduced ring. Finally, we classify Artinian rings whose nil-graphs of ideals have genus at most one.

We present a fully integrated cryogenic controller for electrostatically controlled quantum dots (QDs) implemented in a commercial 22-nm fully depleted silicon-on-insulator CMOS process and operating in a quantum regime. The QDs are realized in local well areas of transistors separated by tunnel barriers controlled by voltages applied to gate terminals. The QD arrays (QDA) are co-located with the control circuitry inside each quantum experiment cell, with a total of 28 of such cells comprising this system-on-chip (SoC). The QDA structure is controlled by small capacitive digital-to-analog converters (CDACs) and its quantum state is measured by a single-electron detector. The SoC operates at a cryogenic temperature of 3.4K. The occupied area of each QDA is $0.7 \times 0.4\mu \text{m}^2$ , while each QD occupies only $20 \times 80 \text{nm}^2$ . The low power and miniaturized area of these circuits are an important step on the way for integration of a large quantum core with millions of QDs, required for practical quantum computers. The performance and functionality of the CDAC are validated in a loop-back mode with the detector sensing the CDAC-compelled electron tunneling from the quantum point contact (QPC) node into the quantum structure. The position of the injected charge inside the QDA is intended to be controlled through the CDAC codes and programmable pulse width. Quantum effects are shown by an experimental characterization of charge injection and quantization into the QDA consisting of three coupled QDs. The charge can be transferred to a QD and sensed at the QPC, and this process is controlled by the relevant voltages and CDACs.

Background: Accurate risk stratification of critically ill patients with coronavirus disease 2019 (COVID-19) is essential for optimizing resource allocation, delivering targeted interventions, and maximizing patient survival probability. Machine learning (ML) techniques are attracting increased interest for the development of prediction models as they excel in the analysis of complex signals in data-rich environments such as critical care. Methods: We retrieved data on patients with COVID-19 admitted to an intensive care unit (ICU) between March and October 2020 from the RIsk Stratification in COVID-19 patients in the Intensive Care Unit (RISC-19-ICU) registry. We applied the Extreme Gradient Boosting (XGBoost) algorithm to the data to predict as a binary outcome the increase or decrease in patients’ Sequential Organ Failure Assessment (SOFA) score on day 5 after ICU admission. The model was iteratively cross-validated in different subsets of the study cohort. Results: The final study population consisted of 675 patients. The XGBoost model correctly predicted a decrease in SOFA score in 320/385 (83%) critically ill COVID-19 patients, and an increase in the score in 210/290 (72%) patients. The area under the mean receiver operating characteristic curve for XGBoost was significantly higher than that for the logistic regression model (0.86 vs. 0.69, P

Introduction: Therapeutic drug monitoring (TDM) and pharmacokinetic assessments of vancomycin would be essential to avoid vancomycin-associated nephrotoxicity and obtain optimal therapeutic and clinical responses. Different pharmacokinetic parameters, including trough concentration and area under the curve (AUC), have been proposed to assess the safety and efficacy of vancomycin administration.Methods: Critically ill patients receiving vancomycin at Nemazee Hospital were included in this prospective study. Four blood samples at various time intervals were taken from each participated patient. Vancomycin was extracted from plasma samples and analyzed using a validated HPLC method.Results: Fifty-three critically ill patients with a total of 212 blood samples from June 2019 to June 2021 were included in this study. There was a significant correlation between baseline GFR, baseline serum creatinine, trough and peak concentrations, AUCτ, AUC24h, Cl, and Vd values with vancomycin-induced AKI. Based on trough concentration values, 66% of patients were under-dosed (trough concentration 600 μg h/ml) that emphasizes on the superiority of AUC-based monitoring approach for TDM purposes to avoid nephrotoxicity occurrence.Conclusion: The AUC-based monitoring approach would be superior in terms of nephrotoxicity prediction. Also, to avoid vancomycin-induced AKI, trough concentration and AUCτ values should be maintained below the cut-off points.

Abstract We present two cases with diabetes and mucormycosis of the major airways. Both patients underwent fiberoptic bronchoscopic evaluation, showing near‐complete occlusion of major airways with creamy necrotic mass lesions. Prompt and accurate diagnosis is vital to limit the extent of tissue destruction and prevent death due to asphyxia.

Background: Extra corporeal membrane oxygenation (ECMO) has been considered as a crucial modality for the management of acute respiratory distress syndrome (ARDS). Since ECMO is considered to be an invasive modality and may be associated with some complications, there are strict indications for its use. Here we report successful treatment of a case of severe ARDS with Veno-Venous ECMO. Case presentation: A 30 years old male was admitted to Nemazee Hospital in Shiraz with decreased level of consciousness due to cerebral hemorrhage following fibrinolytic therapy for myocardial infarction with ST elevation (STEMI). After diagnosis of moderate to severe ARDS, VV-ECMO was used for the management of ARDS. In this case, 5 days after starting ECMO, PaCO2 improved and O2Sat was maintained at 97-98%, so weaning was considered. Ventilator mode was BIPAP with FiO2 40% and sweep flow was 1.7L/min. We clamped the sweep flow and observed whether the patient was able to maintain O2 Sat at 97% with ventilation alone. Then, we decided to disconnect the patient from ECMO. The patient remained stable afterwards. Conclusion: Our case was intubated and was on MV from 10 days prior to ECMO administration.Moreover, our patient had simultaneous multi-organ involvement (nephrotic syndrome and sepsis) which decreased the benefits of ECMO. Despite all these problems, ECMO was started and patient was discharged from ICU with an acceptable health condition.

Background: Extra corporeal membrane oxygenation (ECMO) has been considered as a crucial modality for the management of acute respiratory distress syndrome (ARDS). Since ECMO is considered to be an invasive modality and may be associated with some complications, there are strict indications for its use. Here we report successful treatment of a case of severe ARDS with Veno-Venous ECMO. Case presentation: A 30 years old male was admitted to Nemazee Hospital in Shiraz with decreased level of consciousness due to cerebral hemorrhage following fibrinolytic therapy for myocardial infarction with ST elevation (STEMI). After diagnosis of moderate to severe ARDS, VV-ECMO was used for the management of ARDS. In this case, 5 days after starting ECMO, PaCO2 improved and O2Sat was maintained at 97-98%, so weaning was considered. Ventilator mode was BIPAP with FiO2 40% and sweep flow was 1.7L/min. We clamped the sweep flow and observed whether the patient was able to maintain O2 Sat at 97% with ventilation alone. Then, we decided to disconnect the patient from ECMO. The patient remained stable afterwards. Conclusion: Our case was intubated and was on MV from 10 days prior to ECMO administration.Moreover, our patient had simultaneous multi-organ involvement (nephrotic syndrome and sepsis) which decreased the benefits of ECMO. Despite all these problems, ECMO was started and patient was discharged from ICU with an acceptable health condition.

Aim: Prophylaxis against stress ulcer in mechanically ventilated patients is one of the causes for ventilator-associated pneumonia (VAP). Our aim was evaluating the effect of intravenous pantoprazole and ranitidine in the incidence of VAP in critically ill patients. Materials and Methods: Patients with at least 48 h of expected mechanical ventilation were allocated randomly to receive either 50 mg ranitidine (R) every 8 h or 40 mg pantoprazole (P) every 12 h intravenously from admission. VAP diagnosis was according to the Clinical Pneumonia Infection Score and positive culture. Results: Eighty-six patients during a 15-month period were analyzed; the study showed a low difference between VAP incidence in the ranitidine and pantoprazole groups. No significant difference was observed in terms of gastrointestinal bleeding, intensive care unit, hospital length of stay, and mortality between the groups. Conclusion: VAP incidence is hardly related to the type of stress ulcer prophylaxis agent with a high rate of VAP and low utilization of VAP prophylaxis bundle.

Abstract Background The complexity of patients’ condition and treatment processes in intensive care units (ICUs) predisposes patients to more hazardous events. Effective patient safety culture is related to lowering the rate of patients’ complications and fewer adverse events. The present study aimed to determine the effect of empowering nurses and supervisors through an educational program on patient safety culture in adult ICUs. Methods A randomized controlled trial was conducted during April–September 2015 in 6 adult ICUs at Namazi Hospital, Shiraz, Iran. A total of 60 nurses and 20 supervisors were selected through proportional stratified sampling and census, respectively, and randomly assigned to the experimental and control groups. The intervention consisted of a two-day workshop, hanging posters, and distributing pamphlets that covered topics such as patient safety, patient safety culture, speak up about safety issues, and the skills of Team Strategies and Tools to Enhance Performance and Patient Safety. Data were collected through a hospital survey on patient safety culture. Eventually, 61 participants completed the study. Data were analyzed using descriptive statistics, independent-samples t-test, paired-samples t-test, and Chi-square test. P

Background and aim: Accurate prediction of prognosis of patients admitted to intensive care units (ICUs) is very important for the clinical management of the patients. The present study aims to identify independent factors affecting death and discharge in ICUs using competing risk modeling. Methods: This retrospective cohort study was conducted on enrolling 880 patients admitted to emergency ICU in Namazi hospital, Shiraz University of Medical Sciences, Shiraz, Iran during 2013-2015. The data was collected from patients’ medical records using a researcher-made checklist by a trained nurse. Competing risk regression models were fitted for the factors affecting the occurrence of death and discharge in ICU. Data analysis was conducted using STATA 13 and R 3.3.3 software. Results: Among these patients, 682 (77.5%) were discharged and 157 (17.8%) died in the ICU. The patients’ mean ± SD age was 48.90±19.52 yr. Among the study patients, 45.57% were female and 54.43% were male. In the competing risk model, age (Sub-distribution Hazard Ratio (SHR)) =1.02, 95% CI: 1.007-1.032), maximum heart rate (SHR=1.009, 95% CI: 1.001-1.019), minimum sodium level (SHR=1.035, 95% CI: 1.007-1.064), PH (SHR=7.982, 95% CI: 1.259-50.61), and bilirubin (SHR=1.046, 95% CI: 1.015-1.078) increased the risk of death, while maximum sodium level (SHR=0.946, 95% CI: 0.908-0.986) and maximum HCT (SHR=0.938, 95% CI: 0.882-0.998) reduced the risk of death. Conclusion: In conclusion, the results of this study revealed several variables that were effective in ICU length of stay (LOS). The variables that independently influenced time-to-discharge were age, maximum systolic blood pressure, minimum HCT, maximum WBC, and urine output, maximum HCT and Glasgow coma score. The results also showed that age, maximum heart rate, maximum sodium level, PH, urine output, and bilirubin, minimum sodium level and maximum HCT were the predictors of death. Furthermore, our findings indicated that the competing risk model was more appropriate than the Cox model in evaluating the predictive factors associated with the occurrence of death and discharge in patients hospitalized in ICUs. Hence, this model could play an important role in managers’ and clinicians’ decision-making and improvement of the standard of care in ICUs.

A simple graph \(G\) is called a compact graph if \(G\) contains no isolated vertices and for each pair \(x\), \(y\) of non-adjacent vertices of \(G\), there is a vertex \(z\) with \(N(x)\cup N(y)\subseteq N(z)\), where \(N(v)\) is the neighborhood of \(v\), for every vertex \(v\) of \(G\). In this paper, compact graphs with sufficient number of edges are studied. Also, it is proved that every regular compact graph is strongly regular. Some results about cycles in compact graphs are proved, too. Among other results, it is proved that if the ascending chain condition holds for the set of neighbors of a compact graph \(G\), then the descending chain condition holds for the set of neighbors of \(G\).

Introduction: Tracheobronchopathia osteochondroplastica (TPO) is a rare benign disorder of the lower part of the trachea and the upper part of the main bronchi. Case Report: A case of tracheobronchopathia osteochondroplastica (TPO) diagnosed at the time of intubation in an intensive care unit due to difficulty when advancing the endotracheal tube beyond the vocal cords, is reported. A problem was encountered which had not been reported previously in TPO: repeated cuff rupture at the time of surgical tracheostomy occurred possibly because of bony and cartilaginous tissue located in the tracheal wall. Conclusion: In addition to difficulty of intubation, TPO may cause tracheostomy tube cuff rupture, which could be explained due to bonny calcification in the tracheal wall.

Background: Clinical assessment of disease severity is an important part of medical practice for prediction of mortality and morbidity in Intensive Care Unit (ICU). A disease severity scoring system can be used as guidance for clinicians for objective assessment of disease outcomes and estimation of the chance of recovery. This study aimed to evaluate the hypothesis that the mortality and length of stay in emergency ICUs predicted by APACHE-IV is different to the real rates of mortality and length of stay observed in our emergency ICU in Iran. Methods: This was a retrospective cohort study conducted on the data of 839 consecutive patients admitted to the emergency ICU of Nemazi Hospital, Shiraz, Iran, during 2012-2015. The relevant variables were used to calculate APACHE-IV. Length of stay and death or discharge, Glasgow coma score, and acute physiology score were also evaluated. Moreover, the accuracy of APACHE-IV for mortality was assessed using area under the Receiver Operator Characteristic (ROC) curve. Results: Of the studied patients, 157 died and 682 were discharged (non-survivors and survivors, respectively). The length of stay in the ICU was 10.98±14.60, 10.22 ± 14.21 and 14.30±15.80 days for all patients, survivors, and non-survivors, respectively. The results showed that APACHE-IV model underestimated length of stay in our emergency ICU (p

Neurobrucellosis is uncommon; however, it is an important complication of brucellosis, which could be seen in any stage of the disease. It presents with different kinds of neurology manifestations and diagnosis is mainly made on history, physical examination and laboratory tests. The clinical course of the disease is relatively insidious and the most common pattern of presentation is subacute or chronic. It has a long-term treatment period and its response to treatment is slow. Here, we report a case of an apparent healthy 25 yr-old Afghani woman from Fars Province (south of Iran) that presented at first with hyperacute onset of headache and abnormal behavior and diagnosed neurobrucellosis in Nov 2015. In endemic areas, neurobrucellosis should be considered for each patient referred with unexplained neurological problems.

Introduction:APACHE (Acute Physiologic and Chronic Health Evaluation) score is a medical tool designed to measure the severity of disease for adult patients admitted to Intensive Care Units (ICU). However, it is designed based on the American patients’ data and is not well suited to be used for Iranian people. In addition, Iranian hospitals are not equipped with High Dependency Units which is required for original APACHE. Method: We aimed to design an intelligent version of APACHE system for recognition of patients’ hospitalization period in ICUs. The new system can be designed based on Iranian local data and updated locally. Intelligence means that the system has the ability to learn from its previous results and doesn’t need manual update. Results: In this study, this new system is introduced and the technical specifications are presented. It is based on neural networks. It can be trained and is capable of auto-learning. The results obtained from final implemented software show better performance than those obtained from non-local version. Conclusion: Using this method, the efficiency of the prediction has increased from 80% to 90%. Such results were compared with the APACHE outputs to show the superiority of the proposed method.

Bilateral vocal cord paralysis is a rare and preventable complication of anterior cervical discectomy and fusion. Herein, we report a fatal case of bilateral vocal cord paralysis after anterior cervical discectomy and fusion (ACD/F). A 65-year-old man with cervical spine trauma and anterior cord syndrome, following car overturn presented to our emergency department. The patient had C6-T10 prolapsed discs for which ACD/F was performed. In the recovery room he developed stridor and respiratory distress immediately after extubation, and was reintubated. Otolaryngological evaluation revealed bilateral vocal cord paralysis. He later required a tracheostomy but finally died in a rehabilitation center after an acute coronary event. Awake fibroptic intubation is recommended in patients at high risk for preoperative recurrent laryngeal nerve injury. Intraoperative tracheal tube cuff pressure monitoring and modification of surgical approach to neck are recommended to prevent bilateral nerve damage.