On the Spectrum of a Class of Distance-transitive Graphs

Let $\Gamma=Cay(\mathbb{Z}_n, S_k)$ be the Cayley graph on the cyclic additive group $\mathbb{Z}_n$ $(n\geq 4),$ where $S_1=\{1, n-1\}$, \dots , $S_k=S_ {k-1}\cup\{k, n-k\}$ are the inverse-closed subsets of $\mathbb{Z}_n-\{0\}$ for any $k\in \mathbb{N}$, $1\leq k\leq [\frac{n}{2}]-1$. In this paper, we will show that $\chi(\Gamma) = \omega(\Gamma)=k+1$ if and only if $k+1|n$. Also, we will show that if $n$ is an even integer and $k=\frac{n}{2}-1$ then $Aut(\Gamma)\cong\mathbb{Z}_2 wr_{I} {Sym}(k+1)$ where $I=\{1, \dots , k+1\}$ and in this case, we show that $\Gamma$ is an integral graph

Iron Porphyrin-Catalyzed Olefination of Carbonyl Compounds with Ethyl Diazoacetate

Iron(II) meso-tetraphenylporphyrin is an efficient catalyst for the selective olefination of a variety of aromatic and aliphatic aldehydes with use of ethyl diazoacetate in the presence of triphenylphosphine. These reactions gave olefin products in excellent yields (\u3e85%) with high selectivity for the E-isomer (\u3e90%). For the olefination of ketones, the reactions were generally slow and the selectivities were low compared with those observed with aldehydes. Iron(III)meso-tetraphenylporphyrin chloride, reduced in situ, could be used as an olefination precatalyst to produce similar yields and selectivities. The olefination mechanism was investigated and the likely pathways are discussed

Methanol mass poisoning in Iran: Role of case finding in outbreak management

Background There are no guidelines addressing the public health aspects of methanol poisoning during larger outbreaks. The current study was done to discuss the role of active case finding and a national guideline that organizes all available resources according to a triage strategy in the successful management of a methanol mass poisoning in Rafsanjan, Iran, in May 2013. Methods A retrospective cross-sectional study was performed reviewing the outbreak Emergency Operation Center files. The objectives were to describe the characteristics, management and outcome of a methanol outbreak using Active Case Finding to trace the victims. Results A total of 694 patients presented to emergency departments in Rafsanjan after public announcement of the outbreak between 29th May and 3rd June 2013. The announcement was mainly performed via short message service (SMS) and local radio broadcasting. A total of 361 cases were observed and managed in Rafsanjan and 333 were transferred to other cities. Seventy-five and 100 patients underwent hemodialysis (HD), retrospectively. The main indication for HD was refractory metabolic acidosis. Eight patients expired due to the intoxication. Except for the deceased cases, no serum methanol level was available. Conclusion In developing countries, where diagnostic resources are limited, use of active case finding and developing national guidelines can help in the management of large outbreaks of methanol poisonings. © 2014 The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: [email protected]

The Correlation Between Prolonged Corrected QT Interval with the Frequency of Respiratory Arrest, Endotracheal Intubation, and Mortality in Acute Methadone Overdose

Corrected QT interval (QTc) prolongation is long considered as a predisposing factor for the occurrence of torsade de pointes (TdP) and sudden cardiac arrest in methadone maintenance treatment. We aimed to elucidate the correlation between QTc prolongation and in-hospital death, respiratory arrest, and endotracheal intubation in acute methadone-intoxicated patients presenting to the emergency department and to assess the value of QTc in predicting these outcomes. A prospective cross-sectional study with a convenience sample of patients with acute methadone overdose was done. Participants were 152 patients aged 15–65 with negative urinary dipstick test for cyclic antidepressants, no history of other QTc-prolonging conditions and co-ingestions, no severe comorbidities affecting the outcomes, and positive urinary dipstick results for methadone. QTc intervals were measured and calculated in triage-time electrocardiogram (ECG). Death was correlated with QTc (P = 0.014) and length of ICU admission (P < 0.001). In multivariable analysis, death was independently associated only with length of ICU admission [odds ratio (OR) 95 % confidence intervals (95 % CI) 1.36 (1.14–1.61)]. Intubation and respiratory arrest were independently associated with QTc interval [OR (95 % CI) 1.03 (1.02–1.04) and 1.02 (1.01–1.03), respectively]. The receiver operating characteristics curves drawn to show the ability of QTc to predict death, intubation, and respiratory arrest showed thresholds of 470, 447.5, and 450 ms with sensitivity (95 % CI) and specificity (95 % CI) of 87.5 (47.3–99.7), 86.8 (74.7–94.5), and 77.3 (62.2–88.5), respectively. Our study showed that QTc is a potential predictor for adverse outcomes related to acute methadone intoxication. The correlations shown in this study between triage-time QTc and in-hospital respiratory arrest or intubation in methadone overdose may be of clinical value, whether these outcomes are hypothesized to be a reflection of background TdP or intoxication severity. © 2014, Springer Science+Business Media New York

Association of triage time Shock Index, Modified Shock Index, and Age Shock Index with mortality in Emergency Severity Index level 2 patients

BACKGROUND: Shock Index (SI) is considered to be a predictor of mortality in many medical and trauma settings. Many studies have shown its superiority to conventional vital sign measurements in mortality prediction. OBJECTIVES: The objectives were to compare mortality and intensive care unit admission prediction of triage time SI, Modified SI (MSI), and Age SI with each other and with triage time blood pressure in Emergency Severity Index (ESI) level 2 patients. METHODS: A retrospective medical record review was performed in the internal medicine emergency department of a general hospital in Kerman, Iran. Triage time vital signs were used to calculate the indices. Multivarible regression analysis was used to create the final model. RESULTS: A total of 1285 patients triaged to ESI level 2 were enrolled in the study. In the multivariate analysis, SI, MSI, and Age SI were found to be the only variables independently associated with mortality, whereas none of them were associated with intensive care unit admission. Sensitivity, specificity, and area under curve in the receiver operating characteristic curve for the model including SI, MSI, and Age SI were 60.8%, 65.4%, and 0.675, respectively. Sensitivity, specificity, and area under curve did not change significantly by excluding SI, MSI, or Age SI from the final model. CONCLUSION: In nontrauma adult patients, triage time SI, MSI, and Age SI are superior to blood pressure for mortality prediction in ESI level 2. They can be used alone or in combination with similar results, but their low sensitivity and specificity make them usable only as an adjunct for this purpose. Copyright © 2015 Elsevier Inc. All rights reserved