Some remarks on Laplacian eigenvalues and Laplacian energy of graphs

Suppose $mu_1$, $mu_2$, ... , $mu_n$ are Laplacian eigenvalues of a graph $G$. The Laplacian energy of $G$ is defined as $LE(G) = sum_{i=1}^n|mu_i - 2m/n|$. In this paper, some new bounds for the Laplacian eigenvalues and Laplacian energy of some special types of the subgraphs of $K_n$ are presented

On the Szeged and the Laplacian Szeged spectrum of a graph

AbstractFor a given graph G its Szeged weighting is defined by w(e)=nu(e)nv(e), where e=uv is an edge of G,nu(e) is the number of vertices of G closer to u than to v, and nv(e) is defined analogously. The adjacency matrix of a graph weighted in this way is called its Szeged matrix. In this paper we determine the spectra of Szeged matrices and their Laplacians for several families of graphs. We also present sharp upper and lower bounds on the eigenvalues of Szeged matrices of graphs

Assessing the Prevalence of Ectopic Cerebellar Tonsils and Accompanying Symptoms in Individuals with Various Headaches

Objectives: Chiari malformation exhibits well-defined clinical signs, symptoms, and incidence rates in clinical studies. However, cerebellar tonsil ectopia presents with ambiguous symptoms and undetermined incidence rates in numerous studies. Our objective was to determine the incidence of cerebellar tonsil ectopia in individuals with headaches and identify additional clinical symptoms. This aims to improve diagnosis accuracy for clinicians and neurologists, leading to more effective treatment approaches. Methods: A cross-sectional study conducted in 2022 included 2305 participants aged 4–78 years presenting with headache. Chiari malformation was diagnosed using magnetic resonance imaging (MRI) scans, with a definition of cerebellar tonsil herniation extending beyond 5mm into the cervical canal. Results: The prevalence of Chiari malformation was 3.4%, with no significant gender difference (p = 0.72). There was a significant correlation between Chiari malformation and headache exacerbation due to the Valsalva maneuver (p < 0.001) and the presence of vertigo (p < 0.001). No significant association was found between Chiari malformation and accompanying symptoms such as nausea (p = 0.43), photophobia (p = 0.2), phonophobia (p = 0.52), and speech disorders (p = 0.45). Conclusion: These findings suggest a notable prevalence of Chiari malformation among headache patients and its association with specific headache characteristics, such as acute and occipital headaches, exacerbation by the Valsalva maneuver, and the co-occurrence of vertigo. These results underscore the need to consider Chiari malformation in the differential diagnosis of patients presenting with these specific headache features

Clonidine Versus Chloral Hydrate for Recording Sleep EEG in Children

ObjectiveOne of the difficulties for conduct electroencephalography (EEG) in pediatric patient population is that they are not always cooperative during the procedure. Different medications have been used to induce sedation during EEG recording. In order to find a medication with least adverse effects and high efficacy, we aimed to compare clonidine and chloral hydrate as a premedication prior EEG performing in pediatric population. Materials &amp; MethodsA prospective, randomized, single-blinded, controlled trial was carried out over 198 children (9 to 156 months) to investigate the sedative and adverse effects of clonidine and chloral hydrate. Patients, partially sleep-deprived the night before, were randomly divided in two groups of clonidine (100 patients) and chloral hydrate (98 patients), on an alternative day basis.Results The average sleep onset latency was significantly longer in the clonidine group than chloral hydrate group (Mann-Whitney test, p &lt; 0.0001). Sleep duration ranged between 15-150 minutes and it was not significantly different between two groups (Mann-Whitney test p = 0.2). Drowsiness with chloral hydrate terminated faster than with clonidine. Drowsiness after arousal was seen in 58% and 26.1% of patients in the clonidine and chloral hydrate groups respectively that was  significant  (Mann-Whitney test, p = 0.058). EEG results were reported normal in 77 subjects in the chloral hydrate group (77%) and in 69 subjects (69%) in the clonidine group (p = 0.161). Generalized epileptiform discharges  reported significantly  in the clonidine group  (Mann-Whitney test , p = 0.006).ConclusionThe results of this study showed that both chloral hydrate 5% (one ml/kg)and clonidine (4 μg/kg)could be administered as a pre medication agent for EEG recording in children , although drowsiness after arousal of clonidine is greater than chloral hydrate . However, the yield of generalized epileptiform discharges in the clonidine group was more than the chloral hydrate group.

Human papillomavirus and cancer : immunological consequences of MHC Class I down-regulation

Few studies have been conducted on the causative factors associated with the development of cancer. Infection\ud by high risk human papillomaviruses (HPVs) have been implicated as causative agents in a variety of cancers.\ud HPV is capable of evading immune system and establishing persistent infections. Prolonged infection and lesion\ud maintenance are associated with higher risk of neoplastic progression. Hence, curtailing the ability of the virus to\ud escape host immunosurveillance should reduce this risk by accelerating resolution of infection and lesion\ud progression. One of the potential effectors of HPV escape from host immunosurveillance is the E5 oncoprotein,\ud which we have shown to down-regulate surface major histocompatibility complex class I (MHC I), without\ud apparent effect on non-classical MHC. These effects would interfere with both cytotoxic T lymphocyte (CTL)\ud killing of the virally infected cells, and with the natural killer (NK) cell illumination of infected cells.\ud In this review we address mechanisms of immunomodulation by papillomavirus and discuss our current findings\ud on the association of HPV and cancers.\u

Data on modeling of enzymatic elimination of Direct Red 81 using Response Surface Methodology

In this article, three variables including laccase dose, 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS) dose and pH were used to modeling of Direct Red 81 (DR81) elimination from aqueous solutions by laccase-mediated system. Obtained data indicated that the predicted and experimental values were close for DR81 elimination, and the regression was also able to give a good prediction of response for DR81 elimination (R-Squared = 0.9983). From the experimental, the highest elimination of the DR81 was 95. 5% after 30 min incubation at pH 5, temperature 40 °C, ABTS 0.2 mM, and initial concentration of DR81 50 mg L−1 in the presence of 0.2 U mL−1 of the laccase. The data showed that the laccase can be used as a ''green'' technology for treating of dyes from aqueous solutions. Data analysis was performed using Design-Expert version 7.0.0 (Stat-Ease, trial version). Keywords: Laccase, Dye, Direct Red 81, Elimination, Box–Behnke

Direct Blue 71 removal from aqueous solution by laccase-mediated system; A dataset

The removal of Direct Blue 71 (DB71), by laccase (EC 1.10.3.2, p-bezenediol:dioxygen oxidoreductases) enzyme in presence of 2,2′-Azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS), in aqueous solution was investigated. Data on this article focused on the optimizing and modeling of DB71 removal by Response surface method (RSM) based on Box–Behnken design (BBD), through studying the effective variables as follows: ABTS dose (0.05–0.2 mM), Laccase dose (0.05–0.2 U mL−1), and pH (3–7). The results of experimental showed that laccase was able to removal DB71 with removal percentage of 83% at concentration of 50 mg L−1 after 30 min incubation in presence of ABTS 0.2 mM, at temperature 40 °C and pH 5. The Analysis of Variance (ANOVA) for the predicted quadratic model was done and quadratic equation showed significant R-Squared (0.9969), Adjusted R-Squared (0.9914) and Adequate Precision (49.7). The lack of fit is not significant due to p-value prob > F more than 0.05. Keywords: Laccase, Dye, Direct Blue 71, Removal, Response surface method, Box–Behnke

Efficacy of Carvedilol in Patients with Dilated Cardiomyopathy due to Beta-thalassemia major; a Double-blind Randomized Controlled Trial

Objective: Dilated cardiomyopathy is the end result of chronic iron overload in patients with beta thalassemia major. The objective of the present study was to evaluate the safety and efficacy of Carvedilol in patients with beta thalassemia major and dilated cardiomyopathy. Methods: During a six-month period, fourteen patients with beta-thalassemia major and heart failure without diabetes mellitus referred to pediatric cardiology clinic enrolled in this double blind, randomly assigned study. All patients were on anti failure therapy with Digoxin, Captopril and Furosemide. Carvedilol was started at a dosage of 3.12 mg bid and for patients who had a systolic blood pressure >100 mmHg, heart rate >60/min and no signs of low cardiac output the dosage was increased every two weeks to a maximum of 25 mg bid. Clinical signs and symptoms, systolic and diastolic echocardiographic indexes and Tissue Doppler Imaging (TDI) data were collected from each patient. Findings: Eight patients received Carvedilol (Group 1) and six received placebo (Group 2). The mean age of patients in Group1 and 2 were 16±0.7 years and 17±3 years respectively. Only one patent in Group 1 tolerated increasing Carvedilol dosage to more than 6.25 mg bid. Changes in New York Heart Association (NYHA) classification, Ejection fraction, End diastolic dimension changes, TDI systolic(S), early (Ea) and late (Aa) diastolic waves were not statistically significant in these two Groups (P>0.05). Pulse Doppler E/A wave ratio of mitral valve in Group1 and Group 2 changed from 1.1±0.37 m/s to 1.8±0.40 m/s and from 1.34±0.30 m/s to 2.6±0.23m/s respectively (P=0.04). Conclusion: Patients with thalassemia and dilated cardiomyopathy have poor tolerance to increasing Carvedilol dosage and develop decreased systolic blood pressure during advancement of the drug dosage. Carvedilol can be effective in prevention of progression of diastolic dysfunction in these patients