A New Achievable Rate Region for Multiple-Access Channel with States

The problem of reliable communication over the multiple-access channel (MAC) with states is investigated. We propose a new coding scheme for this problem which uses quasi-group codes (QGC). We derive a new computable single-letter characterization of the achievable rate region. As an example, we investigate the problem of doubly-dirty MAC with modulo-$4$ addition. It is shown that the sum-rate $R_1+R_2=1$ bits per channel use is achievable using the new scheme. Whereas, the natural extension of the Gel'fand-Pinsker scheme, sum-rates greater than $0.32$ are not achievable.Comment: 13 pages, ISIT 201

Bounds on the Effective-length of Optimal Codes for Interference Channel with Feedback

In this paper, we investigate the necessity of finite blocklength codes in distributed transmission of independent message sets over channels with feedback. Previously, it was shown that finite effective length codes are necessary in distributed transmission and compression of sources. We provide two examples of three user interference channels with feedback where codes with asymptotically large effective lengths are sub-optimal. As a result, we conclude that coded transmission using finite effective length codes is necessary to achieve optimality. We argue that the sub-optimal performance of large effective length codes is due to their inefficiency in preserving the correlation between the inputs to the distributed terminals in the communication system. This correlation is made available by the presence of feedback at the terminals and is used as a means for coordination between the terminals when using finite effective length coding strategies

Serogroups, virulence genes and antibiotic resistance in Shiga toxin-producing Escherichia coli isolated from diarrheic and non-diarrheic pediatric patients in Iran

Background: From a clinical perspective, it is important to know which serogroups, virulence genes and antibiotic resistance patterns are present in Shiga toxin-producing Escherichia coli strains in pediatric patients suffering from diarrheic and non-diarrheic infections. This is the first study in Iran that has comprehensively investigated the Shiga toxin-producing Escherichia coli -related infection characteristics in diarrheic and non-diarrheic pediatric patients of 0-60 months of age. Methods. Two-hundred and twenty four diarrheic and 84 non-diarrheic stool specimens were collected from the Baqiyatallah hospital of Tehran, Iran. The stool samples were cultured immediately and those that were E. coli-positive were analyzed for the presence of antibiotic resistance genes and bacterial virulence factors using PCR. Antimicrobial susceptibility testing was performed using disk diffusion method. Results: One-hundred and fifty four out of 224 (68.75%) diarrheic stools and 31 out of 84 (36.90%) non-diarrheic stools harbored E. coli. In addition, children in 13-24 month-old age group had the highest incidence of infection with this bacterium (77.63%). A significant difference was found between the frequency of Attaching and Effacing Escherichia coli and Enterohaemorrhagic Escherichia coli (P =0.045). The genes encoding Shiga toxins and intimin were the most commonly detected virulence factors. Among all serogroups studied, O26 (27.04%) and O111 (18.85%) had the highest incidences in the diarrheic and non-diarrheic patients. The incidence of genes encoding resistance against sulfonamide (sul1), gentamicin (aac(3)-IV), trimethoprim (aadA1), cephalothin (blaSHV) and tetracycline (tetA) were 82.78%, 68.03%, 60.65%, 56.55% and 51.63%, respectively. High resistance levels against penicillin (100%), tetracycline (86.88%), gentamicin (62.29%) and streptomycin (54.91%) were observed. Marked seasonality in the serogroup distributions was evident, while STEC infections were more common in summer (P =0.041). Conclusions: Our findings should raise awareness about antibiotic resistance in diarrheic pediatric patients in Iran. Clinicians should exercise caution when prescribing antibiotics, especially during the warmer months of the year

Prehospital emergency response times for stroke patients in Iran: a cross-sectional study

Background: Stroke is considered as one of the most important causes of emergency medical services (EMS) dispatch worldwide. Stroke is a time-sensitive condition and rapid transport of the patients improves the prognosis. In this study, we described prehospital emergency response times for stroke patients in Isfahan, Iran. Methods: In the current cross-sectional descriptive study, suspected stroke patients who were transported by EMS in Isfahan, Iran, from June 2022 to June 2023 were included. The data was extracted from patients’ files. The time interval between the receipt of a call and the EMS arrival at the scene (arrival time), the time interval between on-scene EMS arrival and the ambulance departure to the medical center (stroke scene time), and the time it takes to reach the medical center (transport time) were collected. Results:  Overall, 79 patients with a mean age of 71.56 ± 12.03 were included. EMS diagnosed 63 (79.75%) of the patients with a definite diagnosis and 14 (17.72%) with probable stroke. Two false negative results were found. The average arrival time, was 11.56 ± 6.60 minutes, on-scene stroke time was 13.85 ± 7.23 minutes and the average transport time was 11.90 ± 6.08 minutes. The mean total EMS response time was 37.90 ±11.29 minutes. Conclusion: Overall, our study showed that while the EMS transport time is longer than ideal, the total time to transport to the hospital is short enough not to affect the outcome. EMS was also found to be adept at spotting the signs of stroke and rapidly starting the process of treatment

Safety and Efficacy of Intraocular Phakic Contact Lens Implantation in Keratoconus Patients

Purpose: To evaluate the safety and efficacy of toric implantable phakic contact lens (IPCL) implantation in the treatment of patients with keratoconus.Patients and Methods: We included 17 eyes from 10 consecutive keratoconus patients who underwent toric IPCL implantation (IPCL V.2, Care Group Sight Solutions, India) in this study. The primary measures were uncorrected distance visual acuity (UCVA), best corrected distance visual acuity (BCVA), sphere, astigmatism, and intraocular pressure (IOP). These parameters were assessed preoperatively and at 1, 3, and 6 months postoperatively. Intraoperative and postoperative complications were also evaluated.Results: The mean age of the patients entering the study was 36 ± 8.8 years. The preoperative BCVA was 0.75 ± 0.21 diopter, improving to 0.86 ± 0.11 diopter postoperatively (P = 0.017). The mean UCVA improved significantly from a preoperative measurement of 0.09 ± 0.11 diopter to 0.78 ± 0.15 diopter postoperatively (P < 0.001). The mean spherical equivalent (SE) showed an enhancement from -6.8 ± 2.1 diopters preoperatively to -0.7 ± 0.3 diopters at the postoperative assessment (P < 0.001). The mean IOP increased from 15.3 mmHg to 16.2 mmHg (P = 0.007) which was statistically significant but clinically insignificant. Additionally, none of the patients experienced postoperative complications such as endophthalmitis, uveitis, IPCL rotation, cataracts, or cystoid macular edema (CME) within the six months following the procedure.Conclusion: The implantation of IPCL in patients with keratoconus appears to be safe and effective. However, further studies with longer follow-ups and larger sample sizes are recommended to validate these findings

Comparison of Verbal Explanations, Graphics, and Film Presentations for Increasing Parental Satisfaction with Lumbar Puncture Performance in Children with Febrile Seizure

AbstractObjective: The present study aimed to determine the effect of training parents by film, poster or graphics, and verbal explanation, on the enhancement of their satisfaction with the performance of this procedure.Materials and Methods: This cross-sectional quasi-experimental study was conducted on the children with febrile seizures referred to the Emergency and Pediatric Wards of hospitals affiliated with Mashhad University of Medical Sciences. They were LP candidates; nonetheless, their parents did not consent to the performance of this procedure. The children were randomly assigned to three groups. In the first group, videos of the location and method of LP were presented to the parents. The second group received this information via posters, and the parents in the third group were given a verbal explanation. Results: The children included 49 (4.54%) females with a mean age of 15 months. There was a significant relationship between the reason for parental refusal of LP and their final satisfaction (P=0.022). There was a significant relationship between parents' satisfaction with the performance of LP and their education (P=0.029). The film method had the lowest chance of success, and the verbal explanation method enjoyed the most remarkable success in enhancing parental satisfaction (P= 0.013).Conclusion: Although the use of posters and videos was less effective than verbal explanation, it increased the satisfaction of LP in some parents. In fact, it is more beneficial to try to alter parental misperceptions of LP in non-emergency situations

Serum vitamin C levels: a comparison between febrile children with or without seizure

Objective: An imbalance has been reported in the oxidant-antioxidant system of infants with febrile convulsion. This study aimed to compare serum vitamin C levels between febrile children with or without seizures. Materials and Method: This multicenter case-control study was conducted on febrile infants and children who were referred to the pediatric emergency wards of Mashhad University of Medical Science. The subjects were equally divided into two febrile groups of case (with seizure) and control (without seizures). Visible Spectrophotometer was used to determine the total vitamin C level.Results: In total, 100 febrile children were included in this study. Based on the results, there was no statistically significant difference between the two groups in terms of age, gender, and family history of febrile convulsion (FC) (P>0.05). The mean vitamin C levels in the case and control groups were 42.73±7.2 and 78.59±11.1 µg/l, respectively. There was a significant difference between the groups regarding the vitamin C level (P<0.001). Regression analysis revealed that age (P=0.74), gender (P=0.66), and family history of febrile convulsion (P=0.52) had not any correlation with vitamin C levels. On the other hand, the vitamin C levels was associated with FC (P=0.001).Conclusion: The serum levels of vitamin C in the children with febrile seizure were lower than those in the control group. Thus, the reduced vitamin C levels can be considered as a predisposing factor for FC

Convulsion Associated with Gastroenteritis

Convulsion with mild gastroenteritis is an afebrile seizure associated with viral gastroenteritis in a healthy child without fever, dehydration, electrolyte imbalance, meningitis, or encephalitis. Convulsion with mild gastroenteritis is more common in children aged 1 to 2 years. Usually, Convulsions are brief generalized tonic colonic type. Most convulsions occur within first 24 hours of illness onset. Rotaviral gastroenteritis is known as the most common type of gastroenteritis associated with Convulsion. Laboratory investigations are normal. Also EEG and neuroimaging are usually normal. Long term antiepileptic treatment is not necessary. It is usually a benign condition with good prognosis and no risk for developing epilepsy in future. Considering this etiology of seizure could prevent supernumerary evaluations and long-term antiepileptic treatment